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  UNIVERSITY OF KANSAS PUBLICATIONS
  MUSEUM OF NATURAL HISTORY


  Volume 7, No. 4, pp. 349-472, 47 figures in text, 4 tables
  April 21, 1954


  North American Jumping Mice
  (Genus Zapus)

  BY

  PHILIP H. KRUTZSCH


  UNIVERSITY OF KANSAS
  LAWRENCE
  1954

  UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY

  Editors: E. Raymond Hall, Chairman, A. Byron Leonard,
  Robert W. Wilson


  Volume 7, No. 4, pp. 349-472, 47 figures in text, 4 tables
  Published April 21, 1954




  UNIVERSITY OF KANSAS
  LAWRENCE, KANSAS


  PRINTED BY
  FERD VOILAND, JR., STATE PRINTER
  TOPEKA, KANSAS
  1954

  25-1128




North American Jumping Mice (Genus Zapus)

by

Philip H. Krutzsch




CONTENTS

                                                                      PAGE

  Introduction                                                         351

  Materials, Methods, and Acknowledgments                              352

  Paleontology of the Genus                                            355

  Relationships, Distribution, and Speciation                          356

  Annotated List of Specific and Subspecific Names                     369

  Characters of Taxonomic Worth                                        371

  Nongeographic Variation                                              376

  Check-List of the Species and Subspecies of the Genus Zapus          382

  Genus Zapus                                                          382

  Artificial Key to the Species of the Genus Zapus                     384

  Systematic Accounts of Species and Subspecies                        385

  _Zapus trinotatus_                                                   385

  _Zapus princeps_                                                     394

  _Zapus hudsonius_                                                    420

  Tables of Measurements                                               455

  Literature Cited                                                     466




INTRODUCTION


The jumping mice (Genus _Zapus_) are widely distributed over northern
North America, occurring as far north as the Arctic Circle and as far
south as Georgia, Missouri, Oklahoma, New Mexico, Arizona, and central
California. In some years these small rodents are locally common in
moist places that are either grassy or weedy; the jumping mice are
notable for the much enlarged hind legs and the exceptionally long tail.

Members of the Genus as a whole have received no serious comprehensive
taxonomic attention in the 54 years since Preble's (1899) revisionary
work. In this time 15 new names have been proposed, mostly for
subspecies, and only a few attempts have been made at grouping related
named kinds.

In the present account it is aimed to record what is known concerning
geographic distribution, taxonomically significant characters, and
interrelationships of the known kinds as well as to provide means for
recognizing the species and subspecies in the genus. In addition,
attention is given to the probable center of origin of the subfamily
Zapodinae and to the relationships and taxonomic positions of the genera
_Zapus_, _Napaeozapus_, and _Eozapus_.




MATERIALS, METHODS, AND ACKNOWLEDGMENTS


The present report is based on a study of approximately 3,600 specimens
that were assembled at the Museum of Natural History of the University
of Kansas or that were examined at other institutions. Most of these
specimens are stuffed skins with skulls separate. Skulls without skins,
skins without skulls, entire skeletons, and separately preserved bacula
are included as a part of the total. Almost every specimen is
accompanied by an attached label, which bears place and date of capture,
name of collector, external measurements, and sex.

Specimens used in the study of geographic variation were arranged by
season of capture and according to geographic location; then they were
segregated as to sex, and, under each sex, by age. Next, individual
variation was measured in comparable samples of like age, sex, season,
and geographic origin. Finally, comparable materials were arranged
geographically in order to determine variations of systematic
significance.

The only external measurements used were total length, length of tail,
and length of hind foot; these measurements were recorded by the
collectors on the labels attached to the skins. Height of the ear was
not used since it was not recorded by many of the collectors.

In order to determine which cranial structures showed the least
individual variation but at the same time showed substantial geographic
variation, a statistical analysis was made of the 30 measurements, of
cranial structures, heretofore used in taxonomic work on _Zapus_. The
following measurements of the skull showed the least individual
variation but showed some geographic variation and therefore, were used
in this study. See figs. 1-3 which show points between which
measurements were taken:

     _Occipitonasal length._--From anteriormost projection of nasal
        bones to posteriormost projection of supraoccipital bone.
        _a_ to _a´_

     _Condylobasal length._--Least distance from a line connecting
        posteriormost parts of exoccipital condyles to a line connecting
        anteriormost projections of premaxillary bones. _b_ to _n_

     _Palatal length._--From anterior border of upper incisors to
        anteriormost point of postpalatal notch. _b_ to _b´_

     _Incisive foramina, length._--From anteriormost point to
        posteriormost point of incisive foramina. _c_ to _c´_

     _Incisive foramina, breadth._--Greatest distance across incisive
        foramina perpendicular to long axis of skull. _f_ to _f´_

     _Zygomatic length._--From anteriormost point of zygomatic process
        of maxillary to posteriormost point of zygomatic process of
        squamosal. _d_ to _d´_

     _Zygomatic breadth._--Greatest distance across zygomatic arches of
        cranium at right angles to long axis of skull. _j_ to _j´_

     _Breadth of inferior ramus of zygomatic process of
        maxillary._--Greatest distance across inferior ramus of zygomatic
        process of maxillary taken parallel to long axis of skull.
        _d_ to _e_

     _Palatal breadth at M3._--Greatest distance from inside margin of
        alveolus of right M3 to its opposite. _g_ to _g´_

     _Palatal breadth at P4._--Same as above except taken at P4.
        _g_ to _g´_

     _Mastoid breadth._--Greatest distance across mastoid bones
        perpendicular to long axis of skull. _h_ to _h´_

     _Breadth of braincase._--Greatest distance across braincase taken
        perpendicular to long axis of skull. _i_ to _i´_

     _Interorbital breadth._--Least distance across top of skull between
        orbits. _k_ to _k´_

     _Length of maxillary tooth-row._--From anterior border of P4 to
        posterior border of M3. _l_ to _l´_

     _Breadth of base zygomatic process of squamosal._--Greatest
        distance across base of zygomatic process of squamosal taken
        parallel to long axis of skull. _m_ to _m´_

    [Illustration: FIGS. 1-3. Three views of the skull to show points
       between which measurements of the skull were taken. Based on
       _Z. t. montanus_, adult, female, No. 22165 KU, Cascade Divide,
       6400 ft., Crater Lake Nat'l Park, Klamath County, Oregon. × 4.]

The baculum has a characteristic size and shape according to the
species, and the following significant measurements of the structure
were taken:

_Greatest length._--From posteriormost border of base to anteriormost
point on tip.

_Greatest breadth at base._--Greatest distance across base taken
parallel to long axis of bone.

_Greatest breadth at tip._--Greatest distance across tip taken parallel
to long axis of bone.

In the descriptions of color the capitalized color terms refer to those
in Ridgway (1912). Any color term that does not have the initial letter
capitalized does not refer to any one standard.

In the description of the subspecies the two sexes are treated as one
because no significant secondary sexual variation was found. Only fully
adult specimens of age groups 3 to 5, as defined on pages 377 and 388,
have been considered.

Unless otherwise indicated, specimens are in the University of Kansas
Museum of Natural History. Those in other collections are identified by
the following abbreviations:

  AMNH.         American Museum of Natural History.
  CAS.          California Academy of Science.
  CM.           Carnegie Museum.
  Chic. AS.     Chicago Academy of Science.
  Clev. MNH.    Cleveland Museum of Natural History.
  LMH.          Collection of Lawrence M. Huey.
  JKJ.          Collection of J. Knox Jones, Jr.
  CMNH.         Colorado Museum of Natural History.
  FM.           Chicago Museum of Natural History.
  HM.           Hastings Museum, Hastings, Nebraska.
  ISC.          Iowa State College.
  MCZ.          Museum of Comparative Zoology.
  MO.           University of Missouri Museum of Zoology.
  MVZ.          Museum of Vertebrate Zoology, Berkeley, Calif.
  NMC.          National Museum of Canada.
  NGFP.         Nebraska Game, Forestation, and Parks Commission.
  NCS.          North Carolina State College.
  OHIO.         Ohio Wildlife Research Unit, Ohio State University.
  OKLA.         Oklahoma Agricultural and Mechanical College.
  PM.           Provincial Museum of British Columbia.
  ROM.          Royal Ontario Museum of Zoology.
  SDM.          San Diego Natural History Museum.
  SITC.         Southern Illinois Teachers College.
  USBS.         United States Biological Surveys Collection.
  USNM.         United States National Museum.
  UCM.          University of Colorado Museum.
  UIM.          University of Illinois Museum of Natural History.
  UM.           University of Michigan Museum of Zoology.
  UU.           University of Utah Museum of Zoology.

The species are arranged from least to most progressive, and the
subspecies are arranged alphabetically.

The synonymy for each subspecies includes first a citation to the
earliest available name then one citation to each name combination that
has been applied to the subspecies and, finally, any other especially
important references.

Marginal records of occurrence for each subspecies are shown on the maps
by means of hollow circles and these localities are listed in clockwise
order beginning with the northernmost locality. If more than one of
these localities lies on the line of latitude that is northernmost for a
given subspecies the western-most of these is recorded first. Marginal
localities have been cited in a separate paragraph at the end of the
section on specimens examined in the account of a subspecies. Localities
that are not marginal are shown on the maps by solid black circles.
Localities that could not be represented on the distribution map because
of undue crowding or overlapping of symbols are italicized in the lists
of specimens examined and in the lists of marginal records.

The localities of capture of specimens examined are recorded
alphabetically by state or province, and then by county in each state or
province. Within a county the specimens are recorded geographically from
north to south. The word "County" is written out in full when the name
of the county is written on the label of each specimen listed for that
county, but the abbreviation "Co." is used when one specimen or more
here assigned to a given county lacks the name of the county on the
label.

The following account has been made possible only by the kindness and
cooperation of those persons in charge of the collections listed above.
For the privilege of using the specimens in their care I am deeply
grateful, as I am also to Prof. A. Byron Leonard for assistance with
figures 35-37, to Dr. Rufus Thompson for figures 16-21, and to Mr.
Victor Hogg who made all of the other illustrations. My wife, Dorothy
Krutzsch, helped untiringly in assembling data, in typing the
manuscript, and gave me continued encouragement. Finally, I am grateful
to Professor E. Raymond Hall for guidance in the study and critical
assistance in the preparation of the manuscript and to Professors Rollin
H. Baker, Robert W. Wilson, and Robert E. Beer for valued suggestions.




PALEONTOLOGY OF THE GENUS


The fossil record of the genus _Zapus_ is scanty. All of the known
fossils of it are lower jaws of Pleistocene Age. The Recent species _Z.
hudsonius_ was recorded by Cope (1871:86) in the Port Kennedy Cave fauna
(pre-Wisconsinian) of Pennsylvania. Gidley and Gazin (1938:67) reported
a single mandibular ramus bearing m1-m3 recovered from the Cumberland
Cave (pre-Wisconsinian) of Maryland. The teeth are not typical of modern
_Zapus_ in that m1 and m2 are shorter crowned and m1 has a longer
anterior lobe. Gidley and Gazin, nevertheless, considered their material
insufficient for establishing a new species.

Two extinct species have been described: _Zapus burti_ Hibbard
(1941:215) from the Crooked Creek formation (= Meade formation of the
State Geological Survey of Kansas) mid-Pleistocene of Kansas and _Zapus
rinkeri_ Hibbard (1951:351) from the Rexroad formation (= Blanco
formation of the State Geological Survey of Kansas) of Blancan Age of
Kansas. Both species resemble _Zapus hudsonius_, but differ from it in
broader crowned more brachydont cheek-teeth. _Z. rinkeri_ differs from
_Z. burti_ and _Z. hudsonius_ by a more robust ramus, broader molars,
and three instead of two internal re-entrant valleys posterior to the
anterior loop on m1. The three species _Z. rinkeri_, _Z. burti_, and _Z.
hudsonius_ are in a structurally, as well as a geologically, progressive
series. The trend in dentition is from broad, brachydont cheek-teeth to
narrow, semi-hypsodont cheek-teeth.




RELATIONSHIPS, DISTRIBUTION, AND SPECIATION


Relationships in the Subfamily Zapodinae

The subfamily Zapodinae is known from Pliocene and Pleistocene deposits
of North America and now occurs over much of northern North America and
in Szechuan and Kansu, China. The living species occur among grasses and
low herbs in damp or marshy places both in forested areas and in plains
areas.

The early Pliocene _Macrognathomys nanus_ Hall (1930:305), originally
described as a Cricetid, is actually a Zapodid as shown by the structure
of the mandibular ramus, shape of the incisors, and occlusal pattern of
the cheek-teeth.

If _Macrognathomys_ can be considered a member of the subfamily
Zapodinae (possibly it is a sicistine) then it represents the oldest
known member of this subfamily. Judging from the published
illustrations, _Macrognathomys_ seems to be structurally ancestral to
the Mid Pliocene _Pliozapus solus_ Wilson; the labial re-entrant folds
are wider and shorter and on m2 and m3 fewer. The difference in stage of
wear of the teeth in _Macrognathomys_ and _Pliozapus_ is a handicap in
comparing the two genera but they are distinct. Wilson (1936:32) points
out that _Pliozapus_ clearly falls in the Zapodinae and stands in an
ancestral position with respect to the structurally progressive series
_Eozapus_, _Zapus_, and _Napaeozapus_. Nevertheless, _Pliozapus_ cannot
be considered as directly ancestral to _Eozapus_ because of the
progressive features in the dentition of _Pliozapus_. Wilson (1937:52)
remarked that if _Pliozapus_ is ancestral to _Zapus_ and _Napaeozapus_,
considerable evolution must have taken place in the height of crown and
in the development of the complexity of the tooth pattern. In contrast
to Wilson's opinion, Stehlin and Schaub (1951:313) placed _Pliozapus_
and _Eozapus_ in the subfamily Sicistinae because certain elements in
the occlusal pattern of the cheek-teeth are similar. I disagree with
those authors and hold with Wilson; I consider _Pliozapus_ and _Eozapus_
in the subfamily Zapodinae. In dental pattern _Pliozapus_, as Wilson
(1936:32) pointed out, resembles the Recent Eurasiatic sicistid,
_Sicista_ more than do _Zapus_ or _Napaeozapus_. Nevertheless, from
_Sicista_ Wilson distinguishes _Pliozapus_ and relates it to the
subfamily Zapodinae by: "more oblique direction of protoconid-hypoconid
ridge, anterior termination of this ridge at buccal portion of
protoconid rather than between protoconid and metaconid as in _Sicista_;
cusps more compressed into lophs; cheek-teeth somewhat broader; greater
development of metastylid; greater development of hypoconulid ridge, ...
absence of anteroconid...."

_Eozapus_ is more closely related to _Pliozapus_ than to either _Zapus_
or _Napaeozapus_ (Wilson, 1936:32) but all four genera are in the
subfamily Zapodinae. Stehlin and Schaub (op. cit.:158 and 311) relate
_Eozapus_ to the subfamily Sicistinae on the basis of similarity in the
occlusal pattern of the cheek-teeth of _Eozapus_ and various sicistines.
Stehlin and Schaub do not consider other structures such as the elongate
hind limbs, the shape of malleus and incus, and the shape of the
baculum, in which there is close resemblance to the Zapodinae. It is
these structural similarities as well as those, pointed out by Wilson
(_loc. cit._), in dentition that leads me to place _Eozapus_ in the
subfamily Zapodinae. The early Pleistocene _Zapus rinkeri_ Hibbard shows
that the _Zapus_ stage of development had already been achieved perhaps
as early as the late Pliocene. Hibbard (1951:352) thought that _Zapus
rinkeri_ was not structurally intermediate between _Pliozapus_ and any
Recent species of _Zapus_; although the teeth of _Z. rinkeri_ have the
broader, shallower, re-entrant folds of _Pliozapus_, these teeth are
higher crowned and have an occlusal pattern resembling that of the
Recent species of _Zapus_. The middle Pleistocene species, _Zapus burti_
Hibbard, progressed essentially to the structural level of the Recent
_Zapus hudsonius_, but the molars were more brachydont, broader crowned,
and their enamel folds less crowded. Pleistocene material of
pre-Wisconsin age obtained from cave deposits in Pennsylvania and
Maryland is most nearly like _Zapus hudsonius_. One such cave deposit in
Maryland contained an example of the Recent genus _Napaeozapus_,
indicating that its history dates from at least middle Pleistocene time.

The Asiatic Recent Genus, _Eozapus_, has not progressed much beyond the
Pliocene stage in zapidine evolution if _Pliozapus_ be taken as a
standard; the North American Recent Genus _Zapus_ essentially achieved
its present form by early Pleistocene times, and the Recent Genus
_Napaeozapus_ achieved its more progressive structure by middle
Pleistocene times.

Perhaps _Pliozapus_ and _Eozapus_ represent one phyletic line and
_Zapus_ and _Napaeozapus_ a second line, both of which lines evolved
from a pre-zapidine stock in the Miocene. As mentioned earlier, Wilson
(1936) thinks that _Pliozapus_ is not directly ancestral to _Eozapus_.
Possibly these two genera diverged at an early date; nevertheless, they
are closely related primitive forms.

_Zapus_ and _Napaeozapus_ closely resemble each other and both are
structurally advanced; _Napaeozapus_ seems to have differentiated at a
more rapid rate.

According to Simpson (1947), the occurrence of the same group of mammals
on two different land masses is to be taken as prima facie evidence that
migration has occurred. Keeping in mind then the present geographic
distribution, unspecialized condition of the dentition of _Eozapus_, and
its resemblance to the extinct _Pliozapus_ known from North America but
not from Asia, it may be that _Eozapus_ descended from primitive stock
of a North American jumping mouse that was forced to the periphery
(across the Asiatic North American land bridge) by the more specialized
zapidine stock.

Subsequently or perhaps during the migration of the pre-_Eozapus_ stock
the zapidine stock may have dispersed transcontinentally, occupying most
of northern North America. The unprogressive _Macrognathomys_ and
_Pliozapus_ line which remained in North America may have become
extinct. Any such period of dispersal and climatic equilibrium ended
when glaciers came to cover most of the northern part of the continent
and the mammals living there were forced southward by the ice or
remained in ice-free refugia within the glaciated area. Later, with
melting and retreat of the ice, the jumping mice could have again spread
enough to occupy the northern part of the continent. Such glaciation
isolated segments of the population and aided their evolution into
distinct species.

If it be assumed, as Matthew (1915) did and as Hooper (1952:200) later
on the generic level did, that the region of origin and center of
dispersal for a given group of animals is characterized by the presence
of the most progressive forms, then southeastern Canada and the
northeastern United States make up the area of origin and center of
dispersal in relatively late time of the subfamily Zapodinae. This area
is inhabited by _Zapus hudsonius_ and _Napaeozapus_, the most
progressive members of the subfamily.

As I visualize it, the evolution of the Zapodinae occurred in two
stages: the first stage involved the movement of the primitive
pre-_Eozapus_ stock to Asia and the second stage involved the dispersal,
isolation, and specialization in North America of the more progressive
basic zapidine stock into the present genera _Zapus_ and _Napaeozapus_.


Status of the genera _Eozapus_, _Zapus_, and _Napaeozapus_

The genus _Zapus_ is one of three living genera in the subfamily
Zapodinae. These genera _Zapus_ and _Napaeozapus_ from North America
and _Eozapus_ from China have been variously considered as subgenera of
the genus _Zapus_ (Preble, 1899) or as three separate genera (Ellerman,
1940).

    [Illustration: FIGS. 4-15. Three views of the skull and a lateral
       view of the left lower jaw of each of the Recent genera of the
       subfamily Zapodinae. × 1.5.

    FIGS. 4-7. _Eozapus s. vicinus_, adult, male, No. 240762 USNM,
       Lanchow, Kansu, China.

    FIGS. 8-11. _Zapus h. pallidus_, adult, male, No. 240762 KU,
       5-1/2 mi. N, 1-3/4 mi. E Lawrence, Douglas County, Kansas.

    FIGS. 12-15. _Napaeozapus i. insignis_, adult, male, No. 41109 KU,
       Shutsburg Rd., at Roaring Creek, 600 ft., Franklin County,
       Massachusetts.]

    [Illustration: FIGS. 16-21. Occlusal views of upper and lower right
       cheek-teeth, of the three Recent genera of the subfamily Zapodinae.
       × 12-1/2.

    FIGS. 16 and 19. _Eozapus s. vicinus_, adult (age group 3), male,
       No. 240762 USNM, Lanchow, Kansu, China.

    FIGS. 17 and 20. _Zapus h. alascensis_, adult (age group 2), female,
       No. 29073 KU, E side Chilkat River, 9 mi. W and 4 mi. N Haines,
       Alaska.

    FIGS. 18 and 21. _Napaeozapus i. insignis_, adult (age group 3),
       male, No. 41109 KU, Shutsburg Rd., at Roaring Creek, 600 ft.,
       Franklin County, Massachusetts.

    Note especially the variation in complexity of occlusal pattern,
       width of re-entrant folds, and degree of tubercularity.]

The remarkable similarity of the body form, post-cranial skeleton,
mandibular rami, and general structure of the cranium of _Zapus_,
_Napaeozapus_, and _Eozapus_ indicate their relationship (see figs.
4-15); however, dissimilarity between the groups in the dentition (tooth
number and occlusal pattern), bacula, and ear ossicles provides basis
for considering them distinct genera. As pointed out earlier, _Zapus_
and _Napaeozapus_ appear to be more closely related and progressive and
the Asiatic _Eozapus_ somewhat removed and less progressive.

_Teeth._--According to the complexity in dental pattern and in number
and size of the cheek-teeth, these genera can be arranged in a
structurally progressive series with _Eozapus_ showing the least
complexity and _Napaeozapus_ the most (see figs. 16-21). There are three
distinct molar patterns; one is simple (_Eozapus_) and the others
(_Zapus_ and _Napaeozapus_) are more complex. The complexity is greatest
in _Napaeozapus_, which is characterized by numerous additional flexures
in the enamel and dentine. The simplicity of the molars of _Eozapus_ is
evident in the tuberculate rather than flat-crowned occlusal surface;
the wide, simple, re-entrant bays; the small (or sometimes absent)
anteroconid; and the essentially quadritubercular nature of the teeth.
The molars of _Zapus_ and _Napaeozapus_ are flat crowned; however,
_Zapus_ has wider and fewer re-entrant bays, a smaller anteroconid, and
less complexity in the occlusal pattern. The characteristics of the
molar teeth would tend to indicate a close relationship between _Zapus_
and _Napaeozapus_ and to place _Eozapus_ as primitive.

The absence of P4 in _Napaeozapus_ would lead one to suspect that this
genus has evolved at a more rapid rate than the historically older
_Zapus_ and _Eozapus_ which still retain this structure. The small size
of P4, even in the primitive _Eozapus_, indicates that it has long been
of little use to the mouse. An even greater reduction of P4 in the more
complex dentition of _Zapus_ argues for complete loss of this tooth as
the next step in specialization, such as is seen in the more progressive
_Napaeozapus_. The following parallel columns show selected differences
between the occlusal patterns of the cheek-teeth of the three genera:

BACULUM.--The baculum (os penis) of _Eozapus_ is known to me only from
Vinogradov's (1925) figures of the dorsal and lateral aspects. The
proximal end (base) is laterally expanded, and the shaft tapers
gradually toward the distal end where it expands abruptly into the
spade-shaped tip. In lateral aspect the bone is relatively thick; it is
curved downward slightly from the proximal end to the base of the tip
where it curves upward to a rounded point.

The baculum of _Zapus_ differs from that of _Eozapus_ as follows: base
less expanded horizontally; shaft slenderer; distal end less
spade-shaped except in _Z. trinotatus_. The tip is less expanded in _Z.
princeps_ and is still less so in _Z. hudsonius_. In _Napaeozapus_ the
tip is lanceolate, the base is narrow, and in lateral view the shaft is
slender and curved (see figs. 22-31).

  -----------------------+-----------------------+-----------------------
          _Eozapus_      |         _Zapus_       |     _Napaeozapus_
  -----------------------+-----------------------+-----------------------
  P4--Small              |  Smaller              |  Absent
                         |                       |
  M1--Four wide labial   |  Four moderately      |  Three narrow labial
      re-entrant folds   |  narrow labial        |  re-entrant folds
      of equal length;   |  re-entrant folds     |  of unequal length,
      paracone and       |  of unequal length;   |  1st long, 2d and 3d
      metacone largest   |  1st and 3d longer    |  shorter; paracone
      cusps; anterior    |  than 2d, 4th         |  and metacone larger
      cingulum large.    |  shortest; paracone   |  than in _Zapus_ and
                         |  smaller than in      |  _Eozapus_; anterior
                         |  _Eozapus_; metacone  |  cingulum absent.
                         |  largest cusp;        |
                         |  anterior cingulum    |
                         |  small.               |
                         |                       |
                         |                       |
  M2--Four wide labial   |  Four moderately      |  Narrow labial
      re-entrant folds;  |  narrow labial        |  re-entrant folds,
      2d short, others   |  re-entrant folds     |  variable in number,
      of equal length    |  of unequal length,   |  often as many as 6;
      but longer than    |  1st and 3d long,     |  anterior and
      2d; anterior and   |  2d and 4th short;    |  posterior cingula
      posterior cingula  |  anterior and         |  small; occlusal
      large; occlusal    |  posterior cingula    |  pattern complex.
      pattern simple.    |  moderately large;    |
                         |  occlusal pattern     |
                         |  moderately complex.  |
                         |                       |
                         |                       |
  M3--Three wide labial  |  Two moderately       |  Three narrow labial
      re-entrant folds   |  narrow labial        |  re-entrant folds
      of unequal length, |  re-entrant folds     |  of unequal length,
      1st short, 2d and  |  of equal length;     |  1st long, 2d and
      3d long; anterior  |  anterior and         |  3d short; anterior
      and posterior      |  posterior cingula    |  and posterior
      cingula low,       |  moderately large;    |  cingula large;
      small; occlusal    |  occlusal pattern     |  occlusal pattern
      pattern simple.    |  moderately complex.  |  complex.
                         |                       |
                         |                       |
  m1--Anterior oblique   |  No anterior          |  No anterior
      re-entrant fold    |  re-entrant fold; 4   |  re-entrant fold;
      separating equal   |  moderately narrow    |  narrow lingual
      sized protoconid   |  lingual re-entrant   |  re-entrant folds
      and metaconid      |  folds of equal       |  variable in
      cusps; 3 wide      |  length, 1st joining  |  number, often as
      lingual re-entrant |  1st labial           |  many as 4;
      folds of equal     |  re-entrant fold,     |   anteroconid well
      length;            |  4th joining 2d       |  developed, encloses
      anteroconid absent;|  labial re-entrant    |  1 or 2 small lakes;
      occlusal pattern   |  fold; anteroconid    |  occlusal pattern
      simple; mesoconid  |  well developed,      |  complex; mesoconid
      present.           |  encloses             |  absent.
                         |  small lake; occlusal |
                         |  pattern moderately   |
                         |  complex;             |
                         |  mesoconid absent.    |
                         |                       |
                         |                       |
  m2--Four wide lingual  |  Four moderately      |  Narrow lingual
      re-entrant folds   |  narrow lingual       |  re-entrant folds,
      of unequal length, |  re-entrant folds,    |  variable in number,
      1st short, other   |  1st and 2d long, 3d  |  may be as many as 5;
      3 equal and long;  |  and 4th short, 1st   |  anteroconid large,
      anteroconid        |  joins 1st labial     |  encloses
      moderately large;  |  re-entrant fold      |  complex folds from
      occlusal pattern   |  and 4th joins 2d     |  1st labial re-entrant
      simple.            |  labial re-entrant    |  fold; occlusal
                         |  fold; anteroconid    |  pattern complex.
                         |  large; occlusal      |
                         |  pattern moderately   |
                         |  complex.             |
                         |                       |
                         |                       |
  m3--Three wide lingual |  Three moderately     |  Narrow lingual
      re-entrant folds   |  narrow lingual       |  re-entrant
      of near equal      |  re-entrant folds     |  folds variable in
      length; antero-    |  of unequal length,   |  number, as many as 3;
      conid absent;      |  1st and 2d long, 3d  |  anteroconid present;
      occlusal pattern   |  short; anteroconid   |  occlusal pattern
      simple; 1 labial   |  absent; occlusal     |  complex; 2 labial
      re-entrant fold.   |  pattern moderately   |  re-entrant folds.
                         |  complex; 1 labial    |
                         |  re-entrant fold.     |
  -----------------------+-----------------------+------------------------

    [Illustration: FIGS. 22-31. Dorsal and lateral views of the bacula
       of the Recent genera (and species of the genus _Zapus_) of the
       subfamily Zapodinae. × 10.

    FIGS. 22 and 27. _Eozapus setchuanus_ (after Vinogradov, 1925:585).

    FIGS. 23 and 28. _Zapus t. trinotatus_, adult, No. 94596 MVZ,
       1-1/4 mi. ENE Amboy, 350 ft., Clark County, Washington.

    FIGS. 24 and 29. _Zapus p. princeps_, adult, No. 20870 KU, 3 mi. S
       Ward, Boulder County, Colorado.

    FIGS. 25 and 30. _Zapus h. pallidus_, adult, No. 22954 KU, 4 mi. N,
       1-3/4 mi. E Lawrence, Douglas County, Kansas.

    FIGS. 26 and 31. _Napaeozapus i. insignis_, adult, No. 41110 KU,
       Shutsburg Rd., at Roaring Creek, 600 ft., Franklin County,
       Massachusetts.]

EAR OSSICLES.--The auditory ossicles are of three types which differ
only slightly. These ossicles possibly are more conservative than some
other structures because the ossicles are not so much affected by the
molding influence of the environment.

Instances of variation in the auditory region in mammals in general are
small, even at the family level; therefore, these differences in the
subfamily Zapodinae are offered as additional support for recognizing
_Eozapus_, _Zapus_, and _Napaeozapus_ as distinct genera. The
distinctive features are chiefly in the malleus and incus; the stapes,
however, differs slightly and, therefore, it too is described (see figs.
32-34).

In _Eozapus_ the head of the malleus is narrow, oblong, and rounded
dorsally and attaches to the body by a long, slender, abruptly recurved
neck. The body is weakly pointed ventrally and rounded dorsally. A
beaklike manubrium malleus composed of anterior projecting external and
internal spines extends from the body to the tympanum. The incus has a
dorsally rounded body with an anterior downward snoutlike projection
with which the malleus articulates. The short limb of the incus is broad
basally and narrows somewhat distally. The long limb is narrow and its
articulating lenticular process is a flat circular structure. The limbs
of the stapes are wide-spread and heavy. The neck is short and wide with
a large circular articulating surface.

In _Zapus_ the head of the malleus is angular with an anterior
projecting point and is flattened in dorsal aspect. The neck is slender,
elongate, and gently curved away from the long limb of the incus. The
body is pointed dorsally and rounded ventrally, the reverse of the
condition in _Eozapus_. There is a beaklike manubrium malleus composed
of internal and external anteriorly projecting spines extending from the
body to the tympanum as in _Eozapus_. The incus has a rounded body with
a long angular limb articulating via a small lenticular process with the
stapes. The short limb is narrow but does not taper distally as in
_Eozapus_. The limbs of the stapes are relatively narrow, weak, and
gently curved. The neck is longer and more slender than that of
_Eozapus_.

In _Napaeozapus_ the head and neck of the malleus resemble those of
_Zapus_ but are less robust. The body is more rounded dorsally, having
the curved dorsal surface directed anteriorly rather than posteriorly
(as in _Zapus_) and the lateral surface is nearly flat instead of curved
as in the other genera. The manubrium resembles that of _Eozapus_ and
_Zapus_. The body of the incus is flattened dorsally but otherwise
rounded. The long limb of the incus is angular and longer than that of
_Zapus_. The short limb of the incus is broad at the base and tapers
distally. The limbs of the stapes are narrow, weak, and abruptly curved.
The neck is more slender and elongate than in _Zapus_.

In summary: Only the head and body of the malleus and the short and long
limbs and body of the incus are sufficiently consistent within a given
group to be of taxonomic importance. The similarity in the morphology of
these ossicles indicates a close relationship between all three genera.
_Zapus_ and _Napaeozapus_ resemble one another more than either
resembles _Eozapus_. The differences recorded are constant between the
described groups and, therefore, are considered to be of taxonomic
significance. The differences give basis for dividing the subfamily
Zapodinae into the three genera _Eozapus_, _Zapus_, and _Napaeozapus_.

    [Illustration: FIGS. 32-34. Lateral views of the left ear ossicles
       (articulated) of the Recent genera of the subfamily Zapodinae. × 20.

    FIG. 32. _Eozapus s. vicinus_, adult, male, No. 240762 USNM,
       Lanchow, Kansu, China.

    FIG. 33. _Zapus p. princeps_, adult, male, No. 32858 KU, Medicine
       Wheel Ranch, 28 mi. E Lovell, Big Horn County, Wyoming.

    FIG. 34. _Napaeozapus i. insignis_, adult, male, No. 9544 KU, 3 mi.
       W Base Station, Coos County, New Hampshire.]


Distribution of and Speciation in the Genus _Zapus_

Many of the described kinds of the genus _Zapus_ were initially named as
distinct species (see Preble, 1899). Subsequently (see Hall, 1931), some
of the nominal species were reduced to the rank of subspecies. Only
three species in the genus _Zapus_ are recognized in the following
account. The concept of species adopted here is, in Mayr's (1942:120)
words, this: "Species are groups of actually or potentially
interbreeding natural populations, which are reproductively isolated
from other such groups." The three species are _Z. trinotatus_, _Z.
princeps_, and _Z. hudsonius_. No hybridization is known where two occur
together or where their ranges are adjacent. Each of these species has
several geographically contiguous subspecies.

The three species of _Zapus_ are closely related but are not equally
progressive. If eastern North America is considered to be the region of
origin and center of dispersal of _Zapus_ (see pp. 368-369) the
geographically distant species would be expected to be the least
progressive, and such seems to be the case. _Zapus trinotatus_ is
geographically farthest removed and structurally least progressive.
_Zapus hudsonius_ occurs at the center of dispersal and is the most
progressive structurally whereas _Z. princeps_ is geographically and
structurally intermediate. Structural progressiveness is postulated for
the species that has the simplest (in this instance specialized) baculum
and smallest fourth upper premolar. The phyletic branches of the genus
_Zapus_ possibly developed from geographic segments of a population
radiating from the centrally located progressive group. On continental
areas where a species with a wide and continuous range gives rise to
several daughter species, geographic isolation is thought to be
important in bringing about the formation of species. The unspecialized
populations conceivably occupied an area west of the present Rocky
Mountains and south of latitude 50°. From later Miocene times on,
climatic and geological differentiation occurred in this area, and with
the growth of geological barriers and differentiation of habitat these
unspecialized populations may have been separated into two ecological
groups, one inhabiting the more arid area between the present Rocky
Mountains and the present Cascade Range and Sierra Nevada and the other
group inhabiting the Pacific coastal region. Isolation of each of these
groups probably was not complete. How far differentiation might have
proceeded with incomplete isolation can only be guessed, but at least
incipient differences probably were present and possibly the animals
approached in character those found in these areas today in that the
ecology of the region was much the same as now.

In the region between the Rocky Mountains and the present Cascade Range
and the Sierra Nevada, the flora (in late Pliocene) became semidesert,
which presumably made most of this region uninhabitable for jumping
mice. The aridity probably induced local concentration into boreal
montane islands, thus possibly displacing the populations of the two
species that were in contact.

In Pleistocene times continental glaciation must have interrupted the
contacts between the coastal, intermontane (the area between the present
Rocky Mountains and the present Cascade Range and the Sierra Nevada),
and northern and eastern groups of _Zapus_ or mammals of any genus that
occurred over all of this vast region. The advance of the ice southward
would have increased opportunity for evolution by interposing barriers
that isolated some populations. The populations possibly were
re-established in interglacial periods and then were isolated again by
another descent of glacial ice.

If a population occupied the unglaciated coastal region of Oregon and
Washington it may have been separated from other populations to the
north and east by an ice cap which covered most of the Cascade Range.
The population occupying the intermountain region probably was isolated
from the population to the north and west. The formation of glaciers
presumably reduced the size of areas available to the populations
occupying eastern North America, Alaska, and Canada with the result that
they persisted only in areas south of the ice or in ice-free refugia
(central and western Alaska) within the glaciated area. According to
Axelrod (1948), the flora in the eastern United States during the
Pleistocene furnished most of the stock for the revegetation of southern
and subarctic Canada east of the Rocky Mountains. Eastern populations of
_Z. hudsonius_ (or its progenitors) probably followed the spread of this
vegetation and, thus, extended their range into Canada where they
crossbred with populations advancing south and east from the refugia in
Alaska. Western montane floras, which extended north along the Rocky
Mountains and the Cascade and Coast ranges, probably paved the path for
a northward migration of populations of the intermountain _Z. princeps_
(or its progenitors). Populations of _Z. princeps_ moved eastward from
the present Rocky Mountains, inhabiting the high plains of southern
Canada and the north-central United States. In general, _Zapus
hudsonius_ occupies the region to the north and to the east of that
inhabited by _Zapus princeps_; however, the ranges of the two meet and
overlap in central and northern British Columbia and in the high plains
area of southern Alberta, Saskatchewan, eastern Manitoba, eastern
Montana, North Dakota, and northern South Dakota. In these places of
overlap, owing to range expansion following the retreat of the ice,
there is no sign of interbreeding, indicating that the populations have
attained specific rank.

Populations of both _Z. hudsonius_ and _Z. princeps_ occur together at
Indianpoint Lake, British Columbia. Specimens taken there are readily
sorted into two groups; none is intermediate. The difference in size
between these species there is especially marked; _Z. p. saltator_ there
is a large derivative of _Z. princeps_ and _Z. h. tenellus_ is a
medium-sized _Z. hudsonius_.

_Z. princeps_ minor and _Z. hudsonius intermedius_ have been taken at
several neighboring localities in North Dakota. Although these
geographic races are more nearly of the same size (_minor_ is a small
subspecies of _princeps_ and _intermedius_ is a moderately large
subspecies of _hudsonius_) they do not interbreed. Specimens of _Z. p.
minor_ and _Z. h. intermedius_ have been obtained from an ecologically
homogeneous area in the vicinity of Fort Totten and Devils Lake, North
Dakota. Values obtained from several measurements of the skull and
baculum allow for ready recognition of the two species. The populations
from North Dakota are, however, not so widely divergent as are those
populations from the area of contact in British Columbia. Perhaps the
difference in the degree of distinction between the species at the two
areas of contact is indicative of the length and completeness of
geographic isolation between neighboring populations.

The ranges of _Z. trinotatus_ and _Z. hudsonius_ are not at present in
contact, but the two species differ more strongly than do _hudsonius_
and _princeps_ or _princeps_ and _trinotatus_. Therefore, _trinotatus_
and _hudsonius_ are here considered to be two distinct species.

As pointed out earlier in this discussion, the separation between the
progenitors of _Z. trinotatus_ and _Z. princeps_ probably occurred when
the present Cascade Range and the Sierra Nevada were being formed. From
this time until Pleistocene glaciation an incomplete geographic
isolation was in effect between the populations of the Pacific coast and
the intermountain populations. Perhaps in the region north of the
present Cascade Range there was moderate interbreeding between these
populations and the transcontinental form. There may have been a similar
zone of interbreeding along the crest of the present Cascades where the
intermountain and coastal populations conceivably could have met. At
least incipient characters probably were present when in Pleistocene
time, continental glaciation further isolated the two populations. Since
the retreat of the last ice (Wisconsin) the unprogressive coastal _Z.
trinotatus_ has expanded its range only slightly, reaching as far as
southwestern British Columbia. It seems that ecological difference
rather than the barrier formed by the higher elevations is responsible
for the limited expansion of range. The population of _princeps_ has
extended its range northward to the southern part of the Yukon Territory
but does not occur in coastal southern British Columbia because that
area already was occupied by _Zapus trinotatus_. The ranges of the two
species meet and overlap in southwestern British Columbia. The species
occur sympatrically in Manning Park where, according to Carl _et al._
(1952:77), they occupy the same range in the region of Allison Pass,
Pinewoods, and Timberline Valley. These workers remark that no
intergradation was apparent between individuals of the two species
obtained in the same trap line.

I have examined material of both species from Allison Pass. There the
species differ in color, in the shape of the skull, and in the size and
shape of the baculum. Material from Timberline Valley, an area in which
Carl _et al._ (_loc. cit._) reported both species, here is assigned to
_Z. princeps_. Where bacula have been preserved the identity of the
species is instantly possible.

In summary: First, a population of jumping mice, possibly a monotypic
genus, occurred over most of North America; then this population partly
divided into Pacific northwest, intermountain (from the east slopes of
the present Rocky Mountains to the east slopes of the present Cascade
Range and the Sierra Nevada), and transcontinental (eastern and
northern) groups with the least progressive groups peripheral; a further
reduction or possibly a complete isolation of these populations followed
owing to Pleistocene glaciation (especially in the Wisconsin period);
and, finally, the present day contacts were established between these
populations which by now have differentiated into species. Conceivably,
_Z. burti_ (Blancan age) and _Z. rinkeri_ (mid Pleistocene) may
represent stages in the development of _Z. hudsonius_.




ANNOTATED LIST OF SPECIFIC AND SUBSPECIFIC NAMES

(Applied to the genus _Zapus_ since 1899)


Edward A. Preble's (1899) early revisionary account of the genus _Zapus_
provides an annotated list of the names which had been proposed for
American jumping mice to that date. The present account supplies in
chronological order the names proposed (including the new kinds
described by Preble) in the 54 years since Preble's revision. Detailed
synonymies are given for each kind under the accounts of the
subspecies.

  1899 _campestris_ (_Zapus hudsonius_) Preble, N. Amer. Fauna,
       15:20, August 8, 1899, applies to the jumping mouse of southeastern
       Montana, and the Black Hills region of Wyoming and South Dakota.

  1899 _minor_ (_Zapus princeps_) Preble, N. Amer. Fauna, 15:23,
       August 8, 1899, originally applied to the jumping mouse of the
       prairies of Saskatchewan, but now includes populations of this
       species from the plains of Canada (southern Manitoba to Canadian
       Rockies) and northern United States (Montana, North and South
       Dakota).

  1899 _oregonus_ (_Zapus princeps_) Preble, N. Amer. Fauna, 15:24,
       August 8, 1899, originally applied to the jumping mouse of eastern
       Oregon, but now applies also to populations from southeastern
       Idaho, eastern and central Nevada, and extreme northeastern
       California.

  1899 _major_ (_Zapus_) Preble [= _Zapus princeps oregonus_], N.
       Amer. Fauna, 15:25, August 8, 1899, arranged as a subspecies of
       _Zapus princeps_ by Hall, Univ. California Publ. Zool., 37:10,
       April 10, 1931; here considered a synonym of _Zapus princeps
       oregonus_.

  1899 _nevadensis_ (_Zapus_) Preble [= _Zapus princeps oregonus_],
       N. Amer. Fauna, 15:25, August 8, 1899, arranged as a subspecies of
       _Zapus princeps_ by Hall, Univ. California Publ. Zool., 37:10,
       April 10, 1931; here considered a synonym of _Zapus princeps
       oregonus_.

  1899 _orarius_ (_Zapus_) Preble [= _Zapus trinotatus orarius_], N.
       Amer. Fauna, 15:29, August 8, 1899, applies to the animals from
       southwestern Marin County, California.

  1911 _luteus_ (_Zapus_) Miller [= _Zapus princeps luteus_], Proc.
       Biol. Soc. Washington, 24:253, December 23, 1911, applies to the
       jumping mouse in north-central and southern New Mexico and eastern
       Arizona.

  1913 _australis_ (_Zapus luteus_) Bailey [= _Zapus princeps
       luteus_], Proc. Biol. Soc. Washington, 26:129, May 21, 1913, was
       applied to the jumping mouse of southern New Mexico, but is here
       regarded as a synonym of _luteus_.

  1920 _eureka_ (_Zapus trinotatus_) Howell, Univ. California Publ.
       Zool., 21:229, May 20, 1920, applies to the jumping mouse of the
       humid coastal district of northern California.

  1931 _cinereus_ (_Zapus princeps_) Hall, Univ. California Publ.
       Zool., 37:7, April 10, 1931, applies to the jumping mouse of
       extreme northwest Utah and south-central Idaho.

  1931 _curtatus_ (_Zapus princeps_) Hall, Univ. California Publ.
       Zool., 37:7, April 10, 1931, applies to the jumping mouse of the
       Pine Forest Mountains, Humboldt County, Nevada.

  1931 _palatinus_ (_Zapus princeps_) Hall [= _Zapus princeps
       oregonus_], Univ. California Publ. Zool., 37:8, April 10, 1931, was
       applied to the jumping mouse of Lander and Nye counties, Nevada,
       but is here regarded as a synonym of _oregonus_.

  1932 _kootenayensis_ (_Zapus princeps_) Anderson, Ann. Rept. Nat.
       Mus. Canada for 1931:108, November 24, 1932, applies to the jumping
       mouse of southeastern and central British Columbia, northern Idaho,
       and eastern Washington.

  1934 _idahoensis_ (_Zapus princeps_) Davis, Jour. Mamm., 15:221,
       August 10, 1931, applies to populations in parts of British
       Columbia, Alberta, Idaho, Montana, and Wyoming.

  1939 _utahensis_ (_Zapus princeps_) Hall, Occas. papers Mus. Zool.
       Univ. Michigan, 296:3, November 2, 1934, applies to the jumping
       mouse of southeastern Idaho, western Wyoming, and eastern Utah.

  1941 _burti_ (_Zapus_) Hibbard, Univ. Kansas Publ., Bull. State
       Geol. Surv. Kansas, 38:214, July 14, 1941, refers to two
       fragmentary right rami of Pleistocene age (Borchers fauna) from
       Loc. No. 9, Meade County, Kansas.

  1942 _brevipes_ (_Zapus hudsonius_) Bole and Moulthrop [= Zapus
       hudsonius americanus], Sci. Publ. Cleveland Mus. Nat. Hist., 5:168,
       September 11, 1942, based on specimens from Bettsville, Seneca
       County, Ohio, which are inseparable from _americanus_ that has
       priority.

  1942 _rafinesquei_ (_Zapus hudsonius_) Bole and Moulthrop [= _Zapus
       hudsonius americanus_], Sci. Publ. Cleveland Mus. Nat. Hist.,
       5:169, September 11, 1942, was applied to jumping mouse of
       southeastern Ohio but is here regarded as a synonym of
       _americanus_.

  1943 _ontarioensis_ (_Zapus hudsonius_) Anderson [= _Zapus
       hudsonius canadensis_], Ann. Rept. Provancher Soc. Nat. Hist.,
       Quebec, 1942:52, September 7, 1943, was applied to animals from
       eastern Ontario but is here regarded as a synonym of _canadensis_.

  1950 _pallidus_ (_Zapus hudsonius_) Cockrum and Baker, Proc. Biol.
       Soc. Washington, 63:1, April 26, 1950, refers to the jumping mouse
       from Kansas, Missouri, Oklahoma, Nebraska, and south-central South
       Dakota.

  1951 _rinkeri_ (_Zapus_) Hibbard, Jour. Mamm., 32:351, August,
       1951, refers to single incomplete right ramus of upper Pliocene
       age, Rexroad formation and fauna, from Loc. UM-UK-47, Fox Canyon,
       sec. 25, T. 34S, R. 30W, XI Ranch, Meade County, Kansas.

  1953 _intermedius_ (_Zapus hudsonius_) described as new on page 447
       of this paper.

  1953 _preblei_ (_Zapus hudsonius_) described as new on page 452 of
       this paper.




CHARACTERS OF TAXONOMIC WORTH


EXTERNAL PARTS.--The total length, the length of the tail, and the
length of the hind foot are useful to some extent in distinguishing
species and subspecies. Geographic variation in these measurements is
clinal in some species. For example, _Zapus trinotatus_, which inhabits
the western coast of North America, decreases in size from the northern
to the southern part of its range. There is considerable overlap in
external measurements, in specimens of the same age, between the species
_Z. trinotatus_ and _Z. princeps_, but only slight overlap between _Z.
princeps_ and _Z. hudsonius_ and between _Z. trinotatus_ and _Z.
hudsonius_. If all collectors measured external parts in the same way
the measurements would be more useful for differentiating one species
from another.

PELAGE.--The pelage, both in its entirety and as individual hairs,
provides taxonomic characters as has been pointed out by Moojen
(1948:324) for the genus _Proechimys_, by Williams (1938:239) for the
Insectivora, and by Hausman (1920:496) for several groups of mammals.
In addition to the sensory hairs, facial vibrissae, nasal hairs, and
carpal vibrissae, there are three kinds of hairs in the normal coat of
_Zapus_: guard hairs, overhairs, and underfur. The guard hairs and
underfur differ in different species (see figs. 35-37).

The guard hairs taper at both ends, are elliptical in cross section, and
are wider and longer than the other two kinds of hair. The bases of the
guard hairs are grayish, and the amount of pigment gradually increases
distally to a dark brownish or blackish shade. The guard hairs vary in
greatest diameter from 96 microns to 168 microns, depending upon the
species, and variation in diameter provides characters of taxonomic
worth. No clinal variation in diameter of the guard hairs was detected.
In _Z. hudsonius_ the guard hairs average 115 microns (96-140) and are
significantly narrower than those of _Z. princeps_ and _Z. trinotatus_,
which average 142 microns (130-168) and 141 microns (133-154),
respectively. Pigmentation of the guard hairs contributes little
information useful in separating the species of _Zapus_. All of the
species have a prominent compounded medulla in which the pigment cells
anastomose to form a labyrinthine column.

The individual hair of the underfur is cylindrical and tapers abruptly
at each end; it is short, thin, flexible, and usually is bicolored on
the back and sides of the mouse. The apical zone is yellow-brown (for
example, Ochraceous-Buff) and the proximal part is whitish or grayish,
which gradually darkens to near black subapically.

The width of a hair in the underfur is of no taxonomic significance, in
that individual variation exceeds that between species.

The pattern of the pigment in the medulla of the hair, however, does
vary specifically. Comparable samples from _Z. trinotatus_, _Z.
princeps_, and _Z. hudsonius_ of the same age, sex, and season reveal a
pattern characteristic for each species (see figs. 35-37).

All species of _Zapus_ agree closely in color pattern. A broad
longitudinal dorsal band of some shade of yellow-brown flecked with
black hairs is bordered by a lateral band of a lighter color usually
containing fewer black hairs than on the dorsum. The underparts are
usually white but are sometimes suffused with color resembling that on
the sides. Between the white underparts and the darker color of the
sides there is often a narrow, clear ochraceous stripe. Dorsal and
lateral hairs are uniformly grayish-white at their bases; only the
distal parts of the hairs are responsible for the external color of the
animal.

The pelage of juveniles is usually finer and softer than the pelage of
adults. The lateral and dorsal bands are not so conspicuously marked in
young animals, and individual hairs are not so long or so wide as in
adult animals.

    [Illustration:

    FIGS. 35-37. Photomicrographs of underhairs (middle third) from each
       of the species of the genus _Zapus_. × 500.

    FIG. 35. _Zapus t. orarius_, adult, female, No. 20293 MVZ, 3 mi. W
       Inverness, 300 ft., Marin County, California.

    FIG. 36. _Zapus p. oregonus_, adult, male, No. 47856 KU, Harrison
       Pass R. S., Ruby Mt's, Elko County, Nevada.

    FIG. 37. _Zapus h. pallidus_, adult, male, No. 22954 KU, 4 mi. N,
       1-3/4 mi. E Lawrence, Douglas County, Kansas.]

Preble (1899:7) and Howell (1920:226) remark as to the noticeable
difference between pelages of spring and early fall. The pelage in
spring is described as bright and fresh whereas that in fall is dull and
worn. Actually both bright and worn pelages can occur in any one
population at any one time. Some newly molted individuals are in fresh
unworn pelage; some individuals, which are molting, are in ragged, worn
pelage; and other individuals perhaps could be found to represent
intermediate stages.

Variations from the normal color of the pelage are rare. Among more than
3,000 specimens of _Zapus_ examined there were only 12 individuals (five
_Z. princeps_, 6 _Z. hudsonius_, and 1 _Z. trinotatus_) that were
abnormally colored. A single white spot was noted on each of 10 (5 _Z.
princeps_, 4 _Z. hudsonius_, and 1 _Z. trinotatus_) of these
individuals; the spots were on the dorsal, anterior half of the body.
The skin beneath the patch of white hair was in each animal like that
beneath the neighboring normally-pigmented hair. One specimen of _Z.
hudsonius_ (NMC No. 6669) is everywhere black, excepting the dorsal
surface of the toes of the forefeet. Most of the individual hairs from
various areas of the body are black for their entire length; some,
however, have non-pigmented silvery tips. One specimen of _Z. hudsonius_
(KU No. 645) lacks any black; dorsally the pelage is nearest to
Ochraceous-Buff and it is white on the venter. Individual hairs of the
dorsal area are white for the basal two-thirds of their length (as
compared to gray and brown in the animals with normal pigmentation) and
near Ochraceous-Buff on the distal third (as compared to hairs which are
dark brown tipped with Ochraceous-Buff). The feet and tail are white.

MOLT.--The sequence of molt for _Zapus_ has been ascertained from
examination of the study skins. In all species of this genus there seems
to be only one annual molt in adults. In the young of the year this molt
occurs after August first and before hibernation. All individuals of a
single population do not molt at any one time; females continue to molt
later in the autumn than do the males; some individuals begin the molt
as early as mid-June and others show molt as late as the end of October;
approximately three weeks are required for an individual to complete its
molt (Quimby, 1951:74); readiness for molt and early stages in molt can
be detected (in museum specimens) by the greater thickness of the skin.
Hairs lost accidentally are quickly replaced, regardless of the
condition of the molt.

In _Zapus hudsonius_, new hair appears simultaneously on the anterior
dorsal surface of the nose and on the mid-dorsal surface between the
scapulae. The molt proceeds anteriorly from the shoulders and
posteriorly from the nose. At the same time that the head is covered,
new hair appears on the sides of the body from the forelegs to the
cheeks. New pelage then appears posteriorly, and molt continues as a
wave from these points over the sides and back with the rump receiving
new hair last (see figs. 42 and 43).

In _Zapus princeps_ new hair appears first on the mid-dorsal surface
between the scapulae. From this starting point molt progresses
anteriorly, laterally, and posteriorly. Progress over the head is rapid;
the head receives its new hair sooner than the caudal region. Molt moves
progressively nearer to the base of the tail and progressively nearer to
the mid-ventral surface. The rump is the last area to complete its molt
(see figs. 40 and 41).

The progress of molt in _Z. princeps_ might be likened to the flow of a
drop of paint on the curved surface of a ball where the paint flows in
all directions but is speeded at one point and slowed at the opposite by
a slight tilting of the ball from the horizontal.

In the species _Zapus trinotatus_ new hair appears simultaneously on
the anterior, dorsal surface of the nose and on the mid-dorsal surface
between the scapulae. In this respect the progress of molt of _Z.
trinotatus_ resembles that of _Z. hudsonius_. From these starting points
molt progresses rapidly over the head, the molt moving anteriorly from
the shoulders and posteriorly from the nose with the result that it
covers the dorsal surface of the head; hair then appears on the cheeks
and sides of the neck. The progress of molt on the remaining areas of
the body is comparable to that of _Z. princeps_; molt progresses toward
the tail and toward the mid-ventral line. The rump, as in _Z. princeps_,
is the last area to complete its molt (see figs. 38 and 39).

    [Illustration: FIGS. 38-43. Diagrams showing differences in progress
       of molt in the three species of the genus _Zapus_. All approximately
       1/2 natural size. Figs. 38, 40 and 42 lateral view. Figs. 39, 41 and
       43 dorsal view.

     FIGS. 38 and 39. _Zapus trinotatus._

     FIGS. 40 and 41. _Zapus princeps._

     FIGS. 42 and 43. _Zapus hudsonius._]

BACULUM.--The general shape and dimensions of the baculum (os penis)
provide characters of taxonomic value for the species of _Zapus_ (see
figs. 23-25 and figs. 28-30).

Three measurements--length, transverse diameter at the base, and
transverse diameter at the tip--are easily obtained and are diagnostic.
The bacula of all species are somewhat curved. The measurement of length
used by me does not represent the actual length of the bone, but instead
the chords of the arcs involved.

SKULL.--Some of the structures useful for separating taxonomic entities
may have little or no biological significance to the animals in nature.
Characters mentioned by me are chosen simply for their significance
taxonomically. The zygomata vary in degree of lateral bowing, being
widely bowed in _Z. princeps_ and _Z. trinotatus_, and less so in _Z.
hudsonius_. Differences in zygomatic breadth owing to the degree of
bowing are an aid in differentiating subspecies. The length of the skull
from the occipital condyles to the tip of the longest nasal bone is
useful in separating _Z. hudsonius_ from _Z. trinotatus_ and _Z.
princeps_. The narrowness of the base of the zygomatic process of the
squamosal is useful in distinguishing between _Z. hudsonius_ and _Z.
princeps_, but shows no variation of subspecific worth. The shape and
dimensions of the incisive foramina provide specific and subspecific
characters. The position of the anterior margin of the postpalatal
notch, in relation to the last molars, provides subspecific characters
in _Z. princeps_. In the species _Z. princeps_ the median projection on
the inferior ramus of the zygomatic process of the maxillary is absent
in some subspecies, small in others, and large in some. Shape and
inflation of the auditory bullae, shape of the pterygoid fossae, and
shape of the nasals are useful in determining specific and subspecific
relationships.

TEETH.--The alveolar length of the upper maxillary tooth-rows aids in
distinguishing _Z. hudsonius_ from _Z. princeps_ and _Z. trinotatus_.
Nearly parallel versus anteriorly divergent upper tooth-rows is a
subspecific difference in _Z. princeps_. Variations in the dimensions of
P4 and M1 aid in estimating the relationships of species. The occlusal
pattern shows little variation and was of no use in separating species.




NONGEOGRAPHIC VARIATION


A knowledge of variation resulting from age, individual, or secondary
sexual differences, as opposed to geographic variation between two or
more populations of a single species is important in determining the
reliability of taxonomic characters.

The largest population-sample of _Zapus_ available to me for the study
of nongeographic variation was 63 individuals from various localities in
Keweenaw and Menominee counties, Michigan. Thirty-nine were females and
24 were males. It is on these specimens that this discussion is based.


Age Variation

TEETH.--The teeth provide a valuable standard for age determination in
that they wear at a measurable rate. The molars erupt in sequence from
front to back, and wear shows first on M1 and last on M3. The peglike
permanent P4, of which I have not seen the deciduous precursor, receives
wear at the same time that the molars are being worn. Wear proceeds at
approximately the same rate in the teeth of both the upper jaws and
lower jaws.

In order to be more nearly certain that specimens used in making racial
comparisons were comparable as to age, six age-groups were established,
from youngest to oldest. These groups were based on the degree of wear
on the occlusal surface of the upper cheek-teeth, and are as follows:
group 1, in which M1 and M2 have not reached full and equal height and
show no occlusal wear, and M3 has not erupted or is just breaking
through the alveolus; group 2, in which M1 and M2 have reached full and
equal height and show slight wear, and M3 may be almost or quite equal
in height to M1 and M2 and, when equal, sometimes shows slight wear;
group 3, in which M1 and M2 show wear on all cusps but cusps are
visible, and M3 shows slight wear; group 4, in which P4 shows slight
wear, M1 has cusps and re-entrant folds between cusps mostly gone, M2
shows considerable wear but re-entrant folds are visible, and M3 has
most re-entrant folds and cusps gone; group 5, in which P4 shows
considerable wear, M1 has cusps completely worn away, M2 has re-entrant
folds and cusps worn away, and M3 lacks occlusal pattern except for one
or two lakes; group 6, in which all upper cheek-teeth are without
occlusal pattern.

These groupings are based on continuously variable features, and,
therefore, when the teeth are at certain stages of wear a specimen is
difficult to place in one of two groups.

Age group 1 and 2 include juvenal and subadult animals. Animals of age
groups 3 through 6 are considered adult. Individuals of age groups 3
through 5, including as they do the great majority of the adult
population, were the only age classes used in measuring geographic
variation.

Quimby's (1951:69) data indicate that some mice produce litters at the
age of approximately 2 months, when four-fifths grown. Therefore, sexual
maturity is not always synonymous with morphological maturity.

MEASUREMENTS OF EXTERNAL PARTS.--Data presented here on _Z. hudsonius_
are those recorded by Quimby (1951) on specimens from Anoka County,
Minnesota, and those obtained by me from museum specimens from Menominee
and Keweenaw counties, Michigan.

According to Quimby (1951:65-66) the mean length [= body length] for
three newly born _Z. hudsonius_ is 24.8 mm (24.0-25.5); at the end of
the fourth week of growth the mean length averaged 64.4 mm and at the
13th week 77.6 mm. Rapid growth occurs during the first four weeks, with
the mean length increasing approximately 2.6 times the size at birth.
After the fourth week of development, growth proceeds at a slower rate;
the mean length at 13 weeks is only 3.1 times greater than the mean
length at birth.

In specimens assigned to age groups 1 and 2 the length of the body
averaged 70 and 74.8 mm, respectively. The individuals of both groups
are less than 13 weeks old if we assume that growth proceeds at the same
rate in Michigan as it does in Minnesota.

In the specimens from Michigan of age groups 3, 4, 5, and 6 the average
length of the body is 80.9, 83.7, 89.0, and 83.6, respectively.

According to Quimby (_loc. cit._), the average length of the tail for
three _Z. hudsonius_ at birth was 9.2 mm. (8.5-10.0). During the first
four weeks of development the tail grew rapidly and reached an average
length of 92.0 mm, which was 10 times the length at birth. By the end of
13 weeks of development the average length of the tail for these three
individuals was 119.6 mm or 12 times the average length at birth. The
most rapid growth was early in development: 80 per cent of the growth
of the tail occurred during the first month, after which growth
proceeded at a much slower rate.

Quimby (_loc. cit._) records an average dimension of 4.7 mm (4.5-5.0)
for the length of the hind foot in three newly born _Z. hudsonius_. The
hind foot grew rapidly in length and by the fourth week had increased
5.6 times in its length and averaged 26.3 mm. Growth was much less rapid
from the fourth to the thirteenth week when the hind foot averaged 27.7
mm, only five per cent more than in mice four weeks old. Assuming the
average length of the hind foot of the adults to be 29.0 mm, the hind
foot in individuals 13 weeks old is 96 per cent of the adult size.

According to Quimby (_loc. cit._), the pinna of the ear at birth is
small and folded over the external auditory meatus. The length of the
ear increases proportionately more (29 per cent) than any other external
dimension after the first four weeks of growth.

If the average length of the ear (measured from the crown) of adults is
14.7 mm, the animals from Michigan in age groups 1 and 2 are 91.8 per
cent and 96.5 per cent as large as adults.

    TABLE 1.--Average Dimensions (in Millimeters) for Specimens of
       Z. h. hudsonius of Various Ages (Specimens from Michigan).

  ==============+=======+=======+=======+=======+=======+=======
    Age groups  |   1   |   2   |   3   |   4   |   5   |   6
  --------------+-------+-------+-------+-------+-------+-------
  No. examined  |     4 |    13 |    33 |    12 |     3 |     3
  --------------+-------+-------+-------+-------+-------+-------
  Body          |  70.0 |  74.8 |  80.9 |  83.7 |  89.0 |  83.6
  --------------+-------+-------+-------+-------+-------+-------
  Tail          | 113.8 | 118.5 | 122.9 | 125.0 | 125.0 | 118.3
  --------------+-------+-------+-------+-------+-------+-------
  Hind foot     |  28.8 |  28.6 |  28.9 |  29.1 |  28.9 |  29.3
  --------------+-------+-------+-------+-------+-------+-------
  Ear           |  13.5 |  14.2 |  14.7 |  14.8 |  15.0 |  14.3
  --------------+-------+-------+-------+-------+-------+-------

From these data, concerning growth of external parts, it seems that:
growth is most rapid during the four weeks following parturition;
specimens from Michigan, assigned to age groups 1 and 2 on the basis of
tooth wear, are less fully developed and probably younger than mice from
Minnesota, with a known age of 13 weeks; individuals with sufficient
wear on the teeth to be placed in age group 3, if they were obtained in
the late fall, may be young from the first litters of the year or, if
they were obtained in early spring, may be at least one year old;
individuals in age groups 4, 5, and 6 are at least one year old.

SKULL.--The post-embryonic development of the skull is rapid. Animals in
age groups 1 and 2 have skulls which average more than 80 per cent of
the size that is here considered adult (an average size obtained from
age groups 3, 4, and 5). The actual increase in size of certain cranial
elements for various age groups is given in table 2.

In age group 1 the rostrum is relatively short as it is in _Neotoma
micropus_ (J. A. Allen, 1894:235) and juveniles of _Peromyscus truei_
(Hoffmeister, 1951:7). The rostrum lengthens rapidly and there is a
general increase in actual and relative size of the entire preorbital
region; the increase after age group 3 is slower and of lesser
magnitude. Changes with age in the size of the braincase are slight. In
age group 1 the average depth of the braincase is 99.6 per cent of the
adult size; the average breadth of the braincase is 98 per cent of the
adult size, and the average width across the mastoid region is 96.4 per
cent of the adult size. These dimensions indicate that the braincase
reaches full size early. The zygomatic arch, however, undergoes change
with age; there is a gradual increase in breadth owing to lateral bowing
and a gradual lengthening which is in keeping with a general elongation
of the skull anterior to the braincase.

The incisive foramina in age group 1 are short (4.0 mm), broad (2.2 mm
in the middle), and taper to a point at each end. In age group 2 the
foramina have elongated (4.2 mm) and are less pointed posteriorly, but
there is no change in breadth. In age groups 3, 4, 5, and 6 the foramina
become progressively longer (4.5 mm in age group 6), have a relatively
constant breadth (2.2 mm), and become more nearly truncate anteriorly.

    TABLE 2.--Average and Extreme Measurements (in Millimeters) of
       Skulls of Six Age-groups in Specimens of Zapus hudsonius
       from Michigan.

  ===============+============+============+============
    Age groups   |     1      |     2      |     3
  ---------------+------------+------------+------------
  Number         |            |            |
  examined       |      4     |     13     |     33
                 |            |            |
  Occipitonasal  |    20.5    |    21.2    |    22.0
  length         | 20.0  21.2 | 20.8  21.8 | 21.5  23.2
                 |            |            |
  Mastoid        |     9.8    |    10.04   |    10.12
  breadth        |  9.7  10.0 |  9.6  10.4 |  9.5  10.5
                 |            |            |
  Length of      |    8.07    |    9.02    |    9.07
  zygomatic arch |  8.0  8.2  |  8.5  9.3  |  8.5  9.4
                 |            |            |
  Breadth of     |    3.36    |    3.33    |    3.37
  palate at P4   |  3.3  3.5  |  3.1  3.4  |  3.1  3.8
                 |            |            |
  Breadth of     |    2.4     |    2.55    |    2.66
  palate at M3   |  2.3  2.6  |  2.3  2.7  |  2.3  3.2
                 |            |            |
  Palatal        |    8.67    |    8.98    |    9.38
  length         |  8.4  9.1  |  8.8  9.2  |  9.3  9.8
                 |            |            |
  Distance from  |            |            |
  incisors to    |    8.53    |    8.98    |    9.08
  postpalatal    |  8.4  8.7  |  8.5  9.5  |  9.0  9.8
  notch          |            |            |
                 |            |            |
  Interorbital   |    4.25    |    4.19    |     4.2
  breadth        |  4.2  4.3  |  4.0  4.4  |  4.0  4.4
                 |            |            |
  Average length |            |            |
  of upper       |    3.2     |    3.2     |    3.21
  molar series   |  3.2  3.4  |  3.2  3.4  |  2.9  3.5
                 |            |            |
  Breadth of     |    9.5     |    9.58    |    9.61
  braincase      |  9.3  9.7  |  9.2  9.7  |  9.1  10.0
                 |            |            |
  Zygomatic      |    10.33   |    10.49   |    10.55
  breadth        | 10.0  10.7 | 10.4  10.9 | 10.1  11.2
                 |            |            |
  Condylobasal   |    16.9    |    18.33   |    18.80
  length         | 16.6  17.1 | 17.4  19.2 | 18.2  19.5
  ---------------+------------+------------+------------

  ===============+============+============+============
    Age groups   |     4      |     5      |     6
  ---------------+------------+------------+------------
  Number         |            |            |
  examined       |     14     |      3     |      3
                 |            |            |
  Occipitonasal  |    22.7    |    22.9    |    23.0
  length         | 21.8  23.4 | 22.7  23.3 | 22.4  23.7
                 |            |            |
  Mastoid        |    10.12   |    10.3    |    10.36
  breadth        |  9.6  10.7 | 10.0  10.8 | 10.1  10.8
                 |            |            |
  Length of      |    9.25    |     9.5    |    9.35
  zygomatic arch |  9.2  9.4  |  9.5  9.5  |  9.1  9.6
                 |            |            |
  Breadth of     |    3.44    |    3.66    |    3.45
  palate at P4   |  3.1  3.7  |  3.6  3.7  |  3.4  3.5
                 |            |            |
  Breadth of     |    2.74    |    3.11    |    2.77
  palate at M3   |  2.5  3.0  |  3.0  3.2  |  2.6  2.9
                 |            |            |
  Palatal        |    9.59    |    9.73    |     9.8
  length         |  9.0  10.0 |  9.5  9.9  |  9.6  10.1
                 |            |            |
  Distance from  |            |            |
  incisors to    |    9.68    |    9.73    |    9.80
  postpalatal    |  9.2  10.0 |  9.5  9.9  |  9.6  10.1
  notch          |            |            |
                 |            |            |
  Interorbital   |     4.2    |    4.23    |     4.2
  breadth        |  4.0  4.4  |  4.1  4.4  |  4.2  4.2
                 |            |            |
  Average length |            |            |
  of upper       |    3.22    |     3.2    |    3.16
  molar series   |  2.9  3.5  |  3.2  3.2  |  3.1  3.2
                 |            |            |
  Breadth of     |    9.68    |    9.83    |    9.63
  braincase      |  9.3  10.0 |  9.5  10.2 |  9.3  9.9
                 |            |            |
  Zygomatic      |    10.80   |    11.0    |    11.25
  breadth        | 10.7  11.2 | 10.5  11.5 | 11.2  11.3
                 |            |            |
  Condylobasal   |    19.33   |    19.6    |    19.9
  length         | 18.5  19.9 | 19.4  19.8 | 19.5  20.3
  ---------------+------------+------------+------------


Individual Variation

Measurements of external parts in _Zapus_ are more variable than are
measurements of most parts of the skull. As Hoffmeister (1951:16) points
out for _Peromyscus truei_, this variation in external features results
in part from "the difficulties in accurately measuring soft parts of the
anatomy" and also from inconsistencies on the part of collectors in
making these measurements.

A comparison of coefficients of variation (see table 3) for cranial
measurements between populations of like age and sex for the species _Z.
hudsonius_, _Z. princeps_, and _Z. trinotatus_ shows that variation of
approximately the same degree is recorded in corresponding elements in
all species; that is to say, structures which are most variable
individually in _Z. princeps_ are also most variable in _Z. trinotatus_
and _Z. hudsonius_.

Individual variation in the occlusal pattern of the molariform teeth is
slight. In several specimens, however, the re-entrant fold is absent
from the lingual surface of M1. Teeth in addition to the normal number
were recorded for five specimens. In all instances they are in the upper
dentition and usually at the posterior end of the maxillary tooth-row.
In each of four specimens (KU No. 34852, KU No. 32852, MVZ No. 52105,
all _Z. princeps_, and USBS No. 22921, _Z. hudsonius_), there is only a
single additional tooth. One individual (USBS No. 264388, _Z. princeps_)
possessed two extra molars, one in each maxillary tooth-row. The extra
teeth vary in size from those which are only slightly smaller than the
adjacent normal molars to those which are simple, peglike structures. In
four of the five animals the extra teeth are posterior to the normal M3;
in the fifth (MVZ No. 52105) the added tooth is anteriormedial to M3.

    TABLE 3.--Coefficients of Variation for Dimensions of Corresponding
       Parts of the Skull of Three Species of Zapus. The Specimens of
       Zapus hudsonius are from Menominee and Keweenaw counties, Michigan,
       the Zapus princeps are from the Vicinity of Encampment, Wyoming,
       and the Zapus trinotatus from Huntingdon, British Columbia.

  ==============================+=============+============+==============
                                |   _Z. h._   |   _Z. p._  |    _Z. t._
              Species           | _hudsonius_ | _princeps_ | _trinotatus_
  ------------------------------+-------------+------------+--------------
  No. examined                  |      52     |     46     |      19
                                |             |            |
  Mastoid width                 |     2.85    |    1.98    |     2.21
                                |             |            |
  Occipitonasal length          |     2.64    |    1.37    |     1.20
                                |             |            |
  Incisors to postpalatal notch |     3.02    |    2.56    |     2.56
                                |             |            |
  Interorbital constriction     |     2.75    |    3.66    |     3.22
                                |             |            |
  Zygomatic breadth             |     2.74    |    2.54    |     1.94
                                |             |            |
  Maxillary tooth-row           |     4.50    |    4.44    |     3.82
  ------------------------------+-------------+------------+--------------

The size and shape of certain cranial elements vary individually even
between right and left sides of the same animal. The paired parietal
bones in some animals are nearly square and identical. In other animals
these bones are approximately equal and straight on three sides with the
fourth side forming an anterolateral projection; this projection may be
slightly or greatly produced, and opposite elements in a single
individual differ in this respect.

The interparietal also is variable; the lateral arms may be blunted and
not included in the fusion of the squamosal, parietal, and occipital
elements, or the interparietals may be elongated and fused with these
elements. Posterior and anterior borders of the interparietal may be
straight, produced anteriorly, produced posteriorly, or produced
anteriorly and posteriorly.

There is frequently variation in the degree of taper of the nasals. They
may be parallel sided, narrowed distally, or narrowed proximally. There
is some variation in the degree of inflation, in the size, and in the
shape of the frontal bones. The anterior surface of the postpalatal
notch varies individually and may be truncate, anteriorly convex, or
anteriorly concave.

Individual variation in the color of the pelage of animals that are in
the same stage of molt or non-molt is by my observation slight. The
presence of oil in the hair results in a false impression of sleekness
and seemingly darker pigmentation. Abnormal white-spotting dorsally
occurs as does yellow and melanistic coat color. These mutations are
considered in the discussion concerning pelage.


Secondary Sexual Variation

In specimens of the two sexes from similar age groups of _hudsonius_
from Michigan, the mean values for each measurement for the two sexes
differ only slightly or are essentially the same (see table 4). In no
species has secondary sexual variation been found to be greater than
individual variation.

    TABLE 4.--Mean Measurements for Adult Male and Female Z. hudsonius
       of Age Group 2 and Per Cent Difference of Females to Males
       (Specimens from Michigan).

  ==============================+=========+=========+=====================
                                |         |         | Per cent difference,
              Sex               |  Male   | Female  |   females to males
  ------------------------------+---------+---------+---------------------
  No. examined                  |   18    |   15    |
                                |         |         |
  Total length                  | 202.85  | 202.88  |     0.02% larger
                                |         |         |
  Hind foot                     | 122.85  | 122.10  |     0.60% smaller
                                |         |         |
  Mastoid width                 |  10.10  |  10.28  |     1.50% larger
                                |         |         |
  Occipitonasal length          |  22.15  |  22.03  |     0.55% smaller
                                |         |         |
  Incisors to postpalatal notch |   9.39  |   9.33  |     0.64% smaller
                                |         |         |
  Zygomatic breadth             |  10.47  |  10.57  |     0.95% larger
                                |         |         |
  Maxillary tooth-row length    |   3.52  |   3.60  |     0.23% larger
  ------------------------------+---------+---------+---------------------




CHECK-LIST OF THE SPECIES AND SUBSPECIES OF THE GENUS _ZAPUS_


                                                                    PAGE

  _Zapus trinotatus_                                                 385
    _Zapus trinotatus eureka_ A. B. Howell                           389
    _Zapus trinotatus montanus_ Merriam                              390
    _Zapus trinotatus orarius_ Preble                                391
    _Zapus trinotatus trinotatus_ Rhoads                             392

  _Zapus princeps_                                                   394
    _Zapus princeps cinereus_ Hall                                   399
    _Zapus princeps curtatus_ Hall                                   400
    _Zapus princeps idahoensis_ Davis                                401
    _Zapus princeps kootenayensis_ Anderson                          404
    _Zapus princeps luteus_ Miller                                   406
    _Zapus princeps minor_ Preble                                    407
    _Zapus princeps oregonus_ Preble                                 409
    _Zapus princeps pacificus_ Merriam                               412
    _Zapus princeps princeps_ Allen                                  414
    _Zapus princeps saltator_ Allen                                  416
    _Zapus princeps utahensis_ Hall                                  418

  _Zapus hudsonius_                                                  420
    _Zapus hudsonius acadicus_ (Dawson)                              432
    _Zapus hudsonius alascensis_ Merriam                             435
    _Zapus hudsonius americanus_ (Barton)                            436
    _Zapus hudsonius campestris_ Preble                              441
    _Zapus hudsonius canadensis_ (Davies)                            442
    _Zapus hudsonius hudsonius_ (Zimmerman)                          443
    _Zapus hudsonius intermedius_ Krutzsch                           447
    _Zapus hudsonius ladas_ Bangs                                    449
    _Zapus hudsonius pallidus_ Cockrum and Baker                     450
    _Zapus hudsonius preblei_ Krutzsch                               452
    _Zapus hudsonius tenellus_ Merriam                               453




Genus =Zapus= Coues


_Genotype._--_Dipus hudsonius_ Zimmerman.

EXTERNAL CHARACTERS.--Muriform in general appearance; forelimbs small,
short; hind limbs greatly developed; hind feet long and narrow; tail
tapering, attenuate, subcylindrical; head long and mouse-shaped; eyes
small and situated midway between nose and ear; external ear somewhat
longer than surrounding hair and provided with antitragal flap which can
cover external auditory meatus, and in company with tragus completely
close opening; upper lip without median groove; internal cheek-pouches
well developed and opening at corners of mouth; mystacial vibrissae
conspicuous; supercilliary vibrissae few; genal tuft absent; teats
normally eight and arranged in pairs (one pectoral, two abdominal, and
one inguinal); anterior and posterior pairs frequently undeveloped;
general pelage coarse; color of pelage varies somewhat in different
species but always follows single basic pattern of broad dorsal band of
some shade of brown or brownish-yellow darkened with brownish-black,
sides of a lighter tone and slightly streaked with brownish-black,
underparts snow-white, sometimes suffused with color of the sides and
usually separated from color of sides by sharp line of clear
brownish-yellow; backs of forefeet and hind feet grayish-white; tail
distinctly bicolor, dark brown above and yellowish-white below; ears
dark and narrowly edged with light color.

    [Illustration: FIG. 44. Map showing distribution of the genus
       _Zapus_.]

CRANIAL CHARACTERS.--Skull short in relation to width, deep relative to
other dimensions, somewhat convex; delicate, papery, without strong
angularity; braincase relatively unexpanded; antorbital foramen
obliquely oval and transmits masseter muscle of great size; foramen in
inferior ramus of zygomatic process of maxillary for passage of superior
maxillary branch of trigeminal nerve small; zygomata not wide-spreading;
underside of zygoma nearly horizontal, upper edge anteriorly rises
prominently owing to extension of jugal upward along maxillary; jugal
and lachrymal in contact; one ramus of zygomatic process of maxilla
arises directly above other; rostrum thick basally and relatively
attenuate distally; ends of nasals project noticeably beyond incisors;
premaxillaries develop strong alveolar plate separating superior
incisors for half their length; palatal bones shortened posteriorly,
free edge often concave; incisive foramina long, broad, and separated by
bulbose (except at posterior end) bony septum; mastoid bullae absent;
auditory bullae short and transversely placed; postorbital process never
present; parietals nearly square, sometimes emarginate in front; angle
of mandible flattened and bent inward; coronoid process weak, acute, and
slopes strongly upward.

DENTAL CHARACTERS.--Dental formula

  I  1, C  O, P  1, M  3
  -- -- -- -- -- -- -- -- = 18;
  i  1  c  o  p  o  m  3

upper incisors short, compressed, curved backward, and strongly grooved;
lower incisors slender, curved backward, and ungrooved; both upper and
lower incisors deep orange or yellow; four upper cheek-teeth present;
premolar small, single rooted and, sometimes, non-functional; upper
molars tri-rooted, sub-hypsodont, and with occlusal surface
non-cuspidate (flat); enamel pattern, much complicated, consisting of
one main re-entrant fold lingually and four re-entrant folds labially;
three lower molars, bi-rooted, sub-hypsodont, flat crowned, with two
outer and four inner re-entrant folds.

POSTCRANIAL CHARACTERS.--Neck short and weak; atlas large; axis separate
from atlas; remaining (5) cervical vertebrae also free; thoracic (12)
and lumbar (7) vertebrae strongly built; posterior lumbars with enlarged
neural and anteriorly directed transverse processes; sacral vertebrae
(7) as in murids; caudal vertebrae variable in number (average 36);
clavicle long, slender, uniformly curved, convex outwardly; scapula with
supraspinous and infraspinous fossae of equal size; forelimbs short,
approximately half as long as hind limbs; hind limbs elongate, slender;
femur with third trochanter; tibia and fibula fused slightly distal to
middle of former; five elongate, separate metatarsals (first and fifth
subequal, shorter than others).




ARTIFICIAL KEY TO THE SPECIES OF THE GENUS ZAPUS


  A.     Baculum with tip spade-shaped and tip wider than 0.43 mm;
         underfur with medullary pattern rectangular, cuticular scales
         small; coronoid process of mandible long and slender, angle of
         divergence from condyle broad; angle of mandible turned in and
         wide; pterygoid fossae wide; skull broad in relation to length;
         premolars with crescentine fold on occlusal surface.
                                                 _Zapus trinotatus_ p. 385

  A´.    Baculum with tip lanceolate (not spade-shaped) and tip less
         than 0.43 mm wide; underfur with medullary pattern square or
         rectangular; but, if rectangular, cuticular scales large;
         coronoid process short and broad, angle of divergence from
         condyle narrow; angle of mandible turned inward and small to
         medium; pterygoid fossae usually narrow; skull not broad in
         relation to length; premolars without crescentine fold on
         occlusal surface.

  B(A´). Baculum less than 5.1 mm in total length; guard hair
         averaging 115 micra in diameter; underfur with rectangular
         medullary pattern, cuticular scales large; skull small;
         incisive foramina shorter than 4.6 mm; condylobasal length
         averaging less than 20 mm; length of maxillary tooth-row
         averaging less than 3.7 mm; palatal breadth at M3 less than
         4.2 mm.
                                                  _Zapus hudsonius_ p. 420

  B´.    Baculum more than 5.1 mm in total length; guard hair averaging
         more than 140 micra in diameter; underfur with square medullary
         pattern, cuticular scales moderately large; skull large;
         incisive foramina longer than 4.7 mm; condylobasal length more
         than 21 mm; maxillary tooth-row averaging more than 3.8 mm;
         palatal breadth at M3 more than 4.4 mm.
                                                   _Zapus princeps_ p. 394

SYSTEMATIC ACCOUNTS OF SPECIES AND SUBSPECIES


=Zapus trinotatus= Rhoads

(Synonymy under subspecies)

_Range._--From southwestern British Columbia southward through western
Washington and Oregon and in the humid coastal district of California
almost to the Golden Gate (see fig. 45).

_Characters of the species_: _External._--Size medium to large (total
length 221 mm to 238 mm); tail longer than head and body (131 mm to 149
mm) and bicolored, brown above, white to yellowish-white below; hind
feet long (31 mm to 34 mm), grayish-white above; back various hues and
tones of ochraceous and tawny; sides paler than back; lateral line
separating sides from ventral surface usually distinct and bright;
ventral coloration white, usually with suffusion of ochraceous; ears
usually dark, sometimes flecked, and usually narrowly edged with color
of sides; guard hairs average 141 microns (133u to 155u) in diameter;
underhair with medullary pigment in narrow, hollow rectangles; cuticular
scales of underhair smaller and more numerous than in other species.

_Baculum._--Size large (total length 6.7 mm to 7.4 mm); base broad (0.7
mm to 0.9 mm); tip broad (0.44 mm to 0.57 mm); spade-shaped in dorsal
aspect and tilted upward, gradually tapering to thin-edged tip; shaft
rounded, straight.

_Skull._--Large, broad and deep in relation to length; pterygoid fossa
broad; anterior ramus of zygomatic process of maxillary relatively
narrow; nasofrontal juncture relatively broad; coronoid process of
mandible elongate. Upper premolars relatively large (averaging .70 mm in
length and .75 mm in width), usually functional, occlusal surface with
labial re-entrant fold forming crescentine loop incompletely enclosing
single central cusp; m3 relatively large, elongated; m1 elongated,
broadly rounded anteriorly.


GEOGRAPHIC VARIATION

There are four subspecies currently recognized, all of which are
confined to the Pacific coastal region of North America (See fig. 45).
The features that vary geographically are external size, color of pelage
(shade and tone of upper parts and tint of lower parts), and dimensions
of certain cranial structures (zygomata, braincase, incisive foramina,
palatal bridge, auditory bullae, and pterygoid fossae).

External size is smallest in the southernmost geographic race (_Z. t.
orarius_) and largest in the northernmost geographic race (_Z. t.
trinotatus_). This decrease in size from north to south is clinal and is
in keeping with Bergman's Rule which postulates that within one species
the smallest individuals occur in the warmer parts of its geographic
range.

    [Illustration: FIG. 45. Map showing distribution of _Zapus
       trinotatus_.

     1. _Z. t. eureka_     3. _Z. t. orarius_
     2. _Z. t. montanus_   4. _Z. t. trinotatus_]

Coloration of pelage is geographically variable. There is a gradual
change in the color of the pelage from north to south. Animals obtained
in the northern part of the geographic range of _Z. trinotatus_ are
generally darker dorsally (more tawny) with the ventral pelage usually
pure white. Those individuals from the southern part of the geographic
range of _Z. trinotatus_ have the dorsal pelage lighter (more reddish
and yellow-brown) and ventrally the pelage is usually heavily suffused
with reddish-brown. The crania also vary geographically; they are
largest in the northernmost part of the range of the species and
smallest in the southernmost part.


NATURAL HISTORY

_Habitat._--On the Olympic Peninsula, Washington, in 1931 Svihla and
Svihla (1933:132) found this species equally abundant in alpine meadows
near timberline, in open grassy areas, and in tall meadow grass and low
blueberry bushes. All of the mice were in wet marshy places. Bailey
(1936:232) reported that in Oregon, these mice live in meadows, marshes,
under ferns and weeds in the woods, or near mountain brooks and streams.
Taylor (1922:221) found _Zapus_ in moderately moist meadows in the
Hudsonian Life-zone at Mt. Rainier, Washington, and Dice (1932:49) found
them in deciduous forest and in open, grassy, or sphagnum bogs. Dice
records it as common also among the alders and willows in high, open,
grassy parks. Merriam (1897b:223) found _Z. trinotatus_ abundantly in
moist places grown-over with grass or weeds. Grass cuttings two to three
inches long were left in small heaps at feeding sites and indicate the
presence of these mice.

_Behavior._--Svihla and Svihla (1933:131) write that the long tail of
_Z. trinotatus_ is used as a balancing organ when the mouse is in
motion. A tailless mouse, attempting to escape, turned somersaults in
the air and invariably landed on its back; the loss of its tail seemed
to leave the mouse without compensation for the vigorous push of the
hind legs. Dalquest (1948:371) noted that the jumping mouse sometimes
walks on all fours, but ordinarily moves by means of short hops on the
hind feet alone. When startled, jumping mice travel in bounds of six
feet or more at a jump.

_Zapus trinotatus_, according to Bailey (1936:232) and Elliot
(1899:261), is mainly nocturnal but occasionally is active in daylight.

Svihla and Svihla (_op. cit._:132) heard captive animals make squeaking
noises when fighting. On several occasions captive animals made a
drumming noise by rapidly beating the tail against a resonant body such
as the bottom of a tin can.

Concerning hibernation, Bailey (_loc. cit._) remarks that animals of
this species in Oregon, become fat in early autumn and lay down excess
adipose tissue under the skin, over the muscles, and in the abdominal
cavity. Svihla and Svihla (_op. cit._:133) noted that captives from the
Olympic Peninsula, Washington, gained weight in September and October
and became extremely fat. With the additional weight they were more
listless and drowsy, often spending days curled up in the hibernating
position with the head between the hind legs and the long tail curled
completely over the head and body. Warmth aroused the animals to
activity, but when the temperature dropped they again hibernated.
Flahaut (1939:17) reported the discovery on February 23, 1939, at
Henderson Inlet, South Bay, Thurston County, Washington, of two nest
cavities inhabited by jumping mice that were hibernating. The nests,
four inches apart and 30 inches below the surface of the ground, were
approximately five inches in diameter and made of shredded paper. Both
mice were dormant, covered by nesting materials and curled up in the
aforementioned hibernating posture. Dalquest (1948: 371) writes that in
the lowlands of Washington this species disappears by late July but that
in the mountains it remains active until the middle of September. Edson
(1932:56) records an individual taken on April 20 from its place of
hibernation beneath the roots of a decaying stump. This animal quickly
roused in the warm mid-afternoon sun but became dormant again when the
temperature dropped to 45° F. It seems that animals near the end of
hibernation become active on warm days and return to the torpid state on
cold ones.

_Enemies._--Little is recorded concerning enemies of _Z. trinotatus_,
but Bailey (1936:233) lists owls and other nocturnal birds, weasels,
skunks, and badgers as preying on this mouse. Smith and Hopkins
(1937:191) found _Z. t. orarius_ in barn owl pellets obtained in Elk
Valley, Marin County, California.

_Food._--Bailey (_loc. cit._) remarks that in Oregon, these mice feed
mainly on small seeds of grasses, small grains (wheat, barley, oats, and
rye), and other plants. These seeds are obtained by cutting the stems,
drawing the stems down and biting off lower sections until the
seed-laden heads are reached. Bailey (_op. cit._:234) found that
_trinotatus_ utilized also the seeds of the western skunk cabbage.

Near Seattle, Washington, according to Dalquest (_loc. cit._), the
principal food of _Z. trinotatus_ was velvet grass (_Holchus lanatus_),
broad-leaved dock, and the seeds of other grasses. Dalquest reports also
that the fruit of the blackberry (_Rubus macropelatus_) is eaten and
that an occasional jumping mouse has its chin stained a deep purple by
juice from these berries.

_Reproduction._--There is normally a single litter of from four to eight
young per year according to Bailey (_loc. cit._). Newly born young have
been described by Svihla and Svihla (1933:132) as follows: slightly
smaller than newly born harvest mice (_Reithrodontomys m. megalotis_),
average weight .8 grams, hairless (without even vibrissae visible),
pink, eyes closed, ears folded, heads short and stubby, tails long
(longer than those of newly born _Peromyscus_), and bodies surprisingly
small (when compared with newly born _Peromyscus maniculatus_).


=Zapus trinotatus eureka= A. B. Howell

    _Zapus trinotatus eureka_ A. B. Howell, Univ. California Publ.,
        Zool. 21:229, May 20, 1920.

    _Zapus trinotatus trinotatus_, Preble, N. Amer. Fauna, 15:26,
        August 8, 1899 (part--the part from Crescent City and Carsons
        Camp, Mad River, California).

    _Zapus orarius_ Preble, N. Amer. Fauna, 15:29, August 8, 1899
        (part--the part from Eureka and Carsons Camp, Mad River,
        California).

_Type._--Female, adult, skin and skull, No. 11703, Mus. Vert. Zool.;
Fair Oaks, Humboldt County, California; obtained on August 27, 1910, by
Joseph S. Dixon, original No. 1743.

_Range._--Northwestern coastal region of California, from Russian Gulch
State Park, Mendocino County north to Trinidad, Humboldt County. Zonal
range: humid Transition.

_Description._--Size medium; color dull; back near Ochraceous-Buff with
heavy admixture of black hairs, forming broad dorsal band; sides from
near Ochraceous-Buff to near Ochraceous-Salmon, sometimes with heavy
admixture of black hairs; lateral line usually distinct, sometimes
blending with color of belly and side; ventral surface usually suffused
with color of sides; tail bicolored, dark brown above, white to
yellowish-white below; feet grayish-white above; ears dark, edged with
color of sides; auditory bullae large; pterygoid fossae broad; incisive
foramina relatively short; palatal bridge short; maxillary tooth-rows
relatively short; narrow across zygomata; braincase narrow; interorbital
region narrow; zygomatic arch relatively short.

_Comparisons._--From _Zapus trinotatus trinotatus_, _Z. t. eureka_
differs in: Size smaller; ventral surface with much greater suffusion of
ochraceous; auditory bullae larger; pterygoid fossae relatively broader;
frontal region less inflated; palatal bridge shorter; braincase
narrower; narrow across zygomata; upper tooth-rows shorter.

For comparison with _Zapus trinotatus orarius_ see account of that
subspecies.

_Remarks._--Howell (1920:230), without having examined the material,
provisionally referred specimens from Requa and Crescent City, Del Norte
County, California, to _Z. t. eureka_. I have studied this material and
find the specimens to be intermediate between _Z. t. trinotatus_ and _Z.
t. eureka_ in cranial characters (zygomatic breadth, interorbital width,
and breadth of braincase), but nearer _Z. t. trinotatus_ in coloration
(absence of ochraceous suffusion ventrally). They are here referred to
_Z. t. trinotatus_. The zone of intergradation between _Z. t.
trinotatus_ and _Z. t. eureka_ seems to extend from Requa, California,
north to Gold Beach, Oregon, where other specimens intermediate between
these two subspecies, have been obtained. These individuals are also
referred to _Z. t. trinotatus_ on the basis of cranial features and
color.

_Specimens examined._--Total, 42, all from California, distributed as
follows: _Humboldt Co._: Trinidad, 4 (SDM); Carsons Camp, Mad River, 3
(USBS); 3 mi. W Arcata, 5 (MVZ); _7-3/10 mi. E Bayside_, 1 (MVZ); _12
mi. S Korbel, on Maple Creek_, 2 (MVZ); _Falk_, 1 (MVZ); Carlotta, 1
(MVZ); _F. B. Summer Redwoods, S Eureka_, 1 (MVZ); _Maple Creek, 1 mi. W
junction Mad River_, 12 (MVZ). _Mendocino County_: Mendocino City, 1
(MVZ); Albion River, 1/3 mi. E MacDonalds Ranch, 1 (MVZ); Russian Gulch
State Park, 10 (MVZ).

_Marginal records._--California: Trinidad; Russian Gulch State Park;
Albion River, 1/3 mi. E MacDonalds Ranch; Mendocino City; Carlotta.


=Zapus trinotatus montanus= Merriam

    _Zapus trinotatus montanus_ Merriam, Proc. Biol. Soc. Washington,
        11:104, April 26, 1897; Bailey, N. Amer. Fauna, 55:234,
        August 29, 1936.

    _Zapus montanus_, Preble, N. Amer. Fauna, 15:28, August 8, 1899.

_Type._--Female, adult, skin and skull; No. 79863, U. S. Nat. Mus.,
Biol. Surv. Coll.; Crater Lake, Klamath County, Oregon; obtained on
August 19, 1896, by Edward A. Preble, original No. 1388.

_Range._--From Crater Lake, Klamath County, Oregon, northward along the
Cascade Range into Hood River County, Oregon. Zonal range: Transition
and Canadian.

_Description._--Size medium; back near Ochraceous-Buff with admixture of
black hair, resulting in a grizzled, broad, dorsal band; sides lighter
than back, from near Ochraceous-Buff to near Pinkish-Cinnamon, and lined
with black hair; lateral line distinct; underparts usually pure white,
sometimes with slight suffusion of ochraceous on lower throat and upper
chest; tail bicolored, brown above and yellowish-white below; ears dark,
sometimes flecked with ochraceous, edged with yellowish-white; feet
grayish-white above; braincase relatively narrow; zygomata relatively
short; condylobasal length short; mastoid region relatively narrow;
palatal bridge short; auditory bullae large; frontal region inflated;
pterygoid fossae relatively narrow.

_Comparison._--From _Zapus trinotatus trinotatus_, _Z. t. montanus_
differs as follows: Size averaging smaller; sides more ochraceous, fewer
black hairs; upper parts duller; skull smaller; zygomatic arch shorter,
braincase relatively narrower; frontal region more inflated; pterygoid
fossae relatively narrower; zygomata narrower.

_Remarks._--The systematic status of _Z. t. montanus_ has been in doubt.
Several workers, for example, Howell (1920:227) and Preble (1899:28),
considered it to be a species, and others (Merriam, 1897a:104, Bailey,
1936:234) considered it to be a subspecies of _Z. trinotatus_. _Z.
montanus_ is here considered to be a subspecies of _Z. trinotatus_,
because of the agreement of the two in size and shape of the baculum,
diameter and pigment pattern of the hair, and the over-all proportions
of the skull. In addition, animals from intermediate geographic areas
are available and show actual intergradation.

Intergradation has been noted in specimens from North Santiam River,
3400 ft., Oregon. In color, in length of incisive foramina, in breadth
of braincase, and in width of zygomata these specimens are intermediate
between _Zapus trinotatus montanus_ and _Z. t. trinotatus_, but in the
sum-total of characters they are referable to the former. Specimens from
Lost Creek R. S., 10 mi. SE McKenzie Bridge, are intermediate in color
between _Z. t. trinotatus_ and _Z. t. montanus_; they are referable to
_Z. t. montanus_. The animals available from Brooks Meadow, 4300 ft., 9
mi. ENE Mt. Hood and the one from Mt. Hood, in color, in length of
incisive foramina, and in mastoid width, closely approach _Z. t.
trinotatus_ from Skamania County, Washington, but in the sum-total of
characters are nearest _Z. t. montanus_ and are here referred to
_montanus_.

_Specimens examined._--Total, 35, all from Oregon, distributed as
follows: _Deschutes County_: Tumalo Creek, 15 mi. W Bend, 6100 ft., 3
(MVZ). _Douglas Co._: Diamond Lake, 1 (USBS). _Hood River Co._: Brooks
Meadow, 4300 ft., 9 mi. ENE Mt. Hood, 10 (MVZ); _Mt. Hood_, 1 (USBS).
_Klamath Co._: _Crater Lake_, 3 (MVZ); _1/2 mi. N Government Camp, 6700
ft., Munson Valley, Crater Lake Nat'l Park_, 2 (MVZ); east slope Cascade
Divide, 6400 ft., Crater Lake Nat'l Park, 2; Anna Creek, Mt. Mazama,
6000 ft., 2 (USBS). _Lane Co._: Lost Creek R. S., 10 mi. SE McKenzie
Bridge, 6 (USBS); _Three Sisters, Alder Springs, 4300 ft._, 2 (USBS).
_Linn County_: North Santiam River, 3400 ft., 3 (MVZ).

_Marginal records._--Oregon: Brooks Meadow, 4300 ft., 9 mi. ENE Mt.
Hood; Tumalo Creek, 15 mi. W Bend, 6100 ft.; Anna Creek, Mt. Mazama,
6000 ft.; east slope Cascade Divide, 6400 ft., Crater Lake Nat'l Park;
Diamond Lake; North Santiam River, 3400 ft.


=Zapus trinotatus orarius= Preble

    _Zapus orarius_ Preble, N. Amer. Fauna, 15:29, August 8, 1899.

    _Zapus pacificus_ Merriam, Proc. Biol. Soc. Washington, 11:104,
        April 26, 1897 (part--the part from Point Reyes, Marin County,
        California).

    _Zapus trinotatus orarius_, Hooper, Miscl. Publ. Mus. Zool. Univ.
        Michigan, 59:67, January 12, 1944.

_Type._--Male, adult, skin and skull, No. 250, collection of E. A. and
O. Bangs (now in Mus. Comp. Zool.); Point Reyes, Marin County,
California; obtained on May 14, 1893, by C. A. Allen, original No. 618.

_Range._--Southern and western Marin County, California. Zonal range:
Upper Sonoran areas that are moist yet safe from continuous inundation.

_Description._--Size small; back dark ochraceous, usually overlaid with
black hairs forming broad dorsal band; side lighter than back with
admixture of black hairs; lateral line distinct, usually bright, near
Ochraceous-Buff; under parts strongly suffused with ochraceous; tail
bicolored, white to yellowish-white below and dark brown above; feet
grayish-white above; ears dark, edged with yellowish-white or tan; skull
small; zygomata narrow; braincase narrow; maxillary tooth-rows short;
interorbital region narrow; incisive foramina short; palatal bridge
relatively long; mastoid region relatively broad; occipitonasal length
short.

_Comparison._--From _Zapus trinotatus eureka_, _Z. t. orarius_ differs
in: Size smaller; color, dorsally and laterally, brighter, more
ochraceous; skull averaging smaller in all measurements taken except
length of palatal bridge, where it averages longer; auditory bullae
smaller, less inflated; pterygoid fossae narrower.

_Remarks._--Preble (1899:30) named this jumping mouse as a full species.
Included in the specimens examined were animals from Eureka and Mad
River, Humboldt County, California. Howell (1920:231) retained _Z.
orarius_ as a full species but restricted its range to Marin County,
California, and referred material from northern California, including
the animals from Eureka and Mad River, to a new subspecies (_eureka_) of
the species _Z. trinotatus_. Howell (_loc. cit._) suggested that _Z.
orarius_ had its closest affinity with _Z. t. eureka_ but remarked that
intergrading material was not available. Hooper (1944:68) arranged _Z.
orarius_ as a subspecies of _Z. trinotatus_ and suggested that
intergrades could be expected from geographically intermediate areas,
for example, northern Sonoma County, California.

Although animals from intermediate geographic areas still are not
available to show actual intergradation, I concur with Hooper (_loc.
cit._) and arrange _Z. orarius_ as a subspecies of _Z. trinotatus_. The
close relationship of _Z. orarius_ to _Z. trinotatus_ is evident;
certain diagnostic characters, held in common, are the shape and size of
the os penis, the diameter and pigment pattern of the hair, and the
general configuration of the skull.

Interbreeding in the wild between _Z. t. orarius_ and _Z. t. eureka_
probably does not take place, because these subspecies are separated by
terrain unsuited to jumping mice.

_Specimens examined._--Total, 29, all from California, distributed as
follows: _Marin County_ (MVZ): 3 mi. W Inverness, 300 ft., 14; _5 mi.
NNE Point Reyes Lighthouse_, 12; _W end Elk Valley, 10 ft._, 1; West
Portal, Fort Barry, 2.

_Marginal records._--California: 3 mi. W Inverness, 300 ft.; West
Portal, Fort Barry.


=Zapus trinotatus trinotatus= Rhoads

    _Zapus trinotatus Rhoads_, Proc. Acad. Nat. Sci. Philadelphia,
        1894:42, January 15, 1895.

    _Jaculus hudsonius_, Baird, Repts. Expl. and Surv. 111, 8 (pt. 1):
        433, July 14, 1858 (part--the part from Washington).

    _Zapus hudsonius_, Coues, Bull. U. S. Geol. and Geog. Surv. of the
        Territories, 2nd ser., No. 5:260, 1877 (part--the part from
        Steilacoom [Pierce County], Washington).

    _Zapus imperator_ Elliot, Field Columbian Mus., publ. 30, zool.
        ser., 1:228, February 1, 1899, type from Siegs Ranch, Elwah River,
        Clallam County, Washington.

    _Zapus princeps trinotatus_, Dalquest, Univ. Kansas Publ. Mus. Nat.
        Hist., 2:371, April 9, 1948.

_Type._--Male, adult, skin and skull, No. 360, S. N. Rhoads Coll.; Lulu
Island, mouth of Frazer River, British Columbia; obtained on May 31,
1892, by S. N. Rhoads (type in Philadelphia Acad. Nat. Sci.).

_Range._--Pacific coastal region from Requa, Del Norte County,
California, north in Oregon west of the Cascades, and in Washington
including the Cascades; to southwestern British Columbia.

_Description._--Size large; back from near Ochraceous-Buff to near Tawny
with admixture of black hair forming broad dorsal band; sides lighter
than back from near Ochraceous-Buff to near Tawny; lateral line usually
distinct; belly white, sometimes with faint suffusion of ochraceous on
lower throat and upper chest; tail bicolored, brown above, white to
yellowish-white below; ears dark, sometimes flecked with color of sides,
edged with ochraceous; feet grayish-white above; palatal bridge
relatively short; incisive foramina relatively long; condylobasal region
long; zygomatic width great; braincase relatively broad; distance from
incisors to postpalatal notch relatively great.

_Comparisons._--For comparisons with _Zapus trinotatus montanus_ and
_Zapus trinotatus eureka_ see accounts of those subspecies.

_Remarks._--This subspecies retains most of its diagnostic characters
throughout nearly all parts of its geographic range. Intergradation
occurs between _Z. t. eureka_ and _Z. t. trinotatus_ in extreme
southwestern Oregon and northwestern California (see account of _Z. t.
eureka_). Intergrades between _Z. t. montanus_ and _Z. t. trinotatus_
have been commented on in the account of _Z. t. montanus_. Specimens
from Eugene, Oregon, according to Bailey (1936:232), show affinity to
_Z. t. montanus_ but are considered by him to be _Z. t. trinotatus_.

_Specimens examined._--Total, 238, distributed as follows:

BRITISH COLUMBIA: Alta Lake, on Pac. Gt. Eastern Ry., 2600 ft., 5 (MVZ);
Okanagan, 1 (FM); _Vedder Crossing_, 4 (1 MVZ, 3 PM); _Chilliwack
Valley_, 2 (NMC); 18 mi. S Chilliwack, 1 (MVZ); Cultus Lake, 2 (NMC);
_Lihumption Park, 4500-4800 ft._, 12 (NMC); _Seymour Mtn., 4000 ft._, 8
(1 MVZ, 7 PM); _Cariboo_, 2 (FM); _Sumas_, 8 (1 MVZ, 7 FM); Huntingdon,
40 (NMC); _Parnassus Creek, Black Tusk Meadow, 5200 ft._, 1 (PM); _Howe
Sound, Brackendale_, 2 (NMC); Stanley Park, Vancouver, 1 (PM); _Allison
Pass, Manning Park_, 1 (PM); Manning Park, 2 (PM).

CALIFORNIA: _Del Norte Co._: Crescent City, 11 (6 FM, 5 USBS); Requa, 4
(FM).

OREGON: _Benton County_: _3 mi. N Corvallis_, 2. _Clatsop County_: Old
Fort Clatsop, 100 ft., 11 (MVZ); 7-1/2 mi. S Cannon Beach, 50 ft., 1
(MVZ). _Columbia County_: 7 mi. SE Rainier, 100 ft., 11 (MVZ). _Curry
County_: Gold Beach, 3 (FM). _Douglas County_: Gardiner, 7 (5 MVZ, 2
FM). _Lane County_: Sutton Lake, 6 mi. N Florence, 1 (MVZ). _Lincoln
County_: _Delake_, 3 (2 MVZ); Newport, 2 (MVZ). _Multnomah County_:
Portland, Council Crest, 950 ft., 1 (MVZ). _Tillamook Co._:
_Tillamook_, 1 (MVZ); _9 mi. S Tillamook_, 1 (MVZ); Netarts, 3 (SDM);
Blaine, 3 (MVZ). _Washington County_: 18-1/2 mi. NW Portland, 1300 ft.,
5 (MVZ).

WASHINGTON: _Clallam County_: Deer Lake, 3800 ft., 3. _Clarke County_:
_3-1/2 mi. E and 1-1/2 N Amboy, 3500 ft._, 3 (MVZ); _1-1/2 mi. ENE
Amboy, 3500 ft._, 13 (MVZ); 3-1/2 mi. E and 5 mi. N Yacolt, 500 ft., 1
(MVZ); _1-1/2 mi. W Yacolt, 800 ft._, 11 (MVZ). _Cowlitz County_: _6 mi.
NE Kelso_, 4 (MVZ); _4 mi. E mouth Kalama River_, 5 (MVZ). _King
County_: Lakeridge Tract, S end Forest Ave., Lake Washington, 2 (MVZ);
Seattle 2 (MVZ); Snoqualmie Pass, 5 (MVZ). _Mason County_: Potlatch, 2
(MVZ). _Pacific County_: _1-1/2 mi. N Chinook, 10 ft._, 1 (MVZ); 3-1/2
mi. SE Chinook, 10 ft., 5 (MVZ). _Pierce Co._: 5 mi. E Tacoma, 4 (MVZ);
Puyallup, 3 (1 MVZ, 2 FM); Mt. Rainier, 1 (MVZ); 3 mi. E Ashford, 1
(LMH). _Skamania County_: Ice Caves, 2800 ft., 5 mi. WSW Guler, 1 (MVZ).
_Thurston County_: Boston Harbor, 5 (CAS). _Wahkiakum County_: 4 mi. E
Skamokawa, 5 (MVZ). _Whatcom County_: Baker Lake, 2 (MVZ).

_Marginal records._--British Columbia: Okanagan; Manning Park.
Washington: Baker Lake; Snoqualmie Pass; Mt. Rainier; Ice Caves, 2800
ft., 5 mi. WSW Gulch. Oregon: Portland, Council Crest, 950 ft.
California: Requa; Crescent City. Oregon: Gold Beach; Gardiner; Sutton
Lake, 6 mi. N Florence; Newport; Netarts; Old Fort Clatsop, 100 ft.
Washington: 3-1/2 mi. SE Chinook, 10 ft.; Deer Lake, 3800 ft. British
Columbia: Stanley Park, Vancouver; Alta Lake, 2600 ft.


=Zapus princeps= Allen

(Synonymy under subspecies)

_Range._--The Rocky Mountains region from Yukon south into Arizona and
New Mexico; westward through eastern Oregon and through the Cascades and
Sierra Nevada of California; eastward in the northern Great Plains to
extreme eastern parts of the Dakotas (see fig. 46).

_Characters of the species_: _External._--Size medium to large (total
length 216 mm to 247 mm); tail longer than head and body (129 mm to 148
mm) and bicolored, pale brown to grayish-brown above, white to
yellowish-white below; hind feet long (31 mm to 34 mm), grayish-white
above; back variable from yellowish-gray to salmon-brown and ochraceous;
sides paler than back; lateral line usually present but sometimes
indistinct or entirely absent (when present usually clear
Ochraceous-Buff); ventral coloration white, usually suffused with
ochraceous; ears usually dark, sometimes flecked and usually narrowly
edged with light color; guard hairs average 142 microns (130u to 168u)
in diameter; underhair with medullary pigment in form of hollow squares;
cuticular scales of underhair larger and fewer than in other species.

_Baculum._--Size medium (total length 5.6 mm to 6.6 mm); base moderately
broad (0.7 mm to 0.8 mm); tip narrow (0.26 mm to 0.31 mm) rounded and
dished out in dorsal aspect, blunted; shaft rounded, slightly
sinusoidal, recurved at tip.

_Skull._--Large, not exceptionally broad and deep in relation to length;
rostrum broad but tapering; pterygoid fossa moderately narrow; anterior
ramus of zygomatic process usually broad; incisive foramina usually
broadly rounded and elongate; auditory bullae usually moderately
inflated; coronoid process of mandible relatively short. Upper premolars
of medium size (averaging .55 mm in length and .50 mm in breadth),
sometimes functional, with occlusal surface normally divided by single
shallow re-entrant fold; m1 relatively short, narrow anteriorly.

    [Illustration: FIG. 46. Distribution of _Zapus princeps_.

     Guide to subspecies

     1. _Z. p. cinereus_          7. _Z. p. oregonus_
     2. _Z. p. curtatus_          8. _Z. p. pacificus_
     3. _Z. p. idahoensis_        9. _Z. p. princeps_
     4. _Z. p. kootenayensis_    10. _Z. p. saltator_
     5. _Z. p. luteus_           11. _Z. p. utahensis_
     6. _Z. p. minor_]

GEOGRAPHIC VARIATION

There are 11 subspecies recognized, most of which are in the mountains
of the western United States and southwestern Canada. There is
geographic variation in color, relative proportions of external parts
(tail, hind feet, head, and body), and shape and size of the skull.

Three basic types of coloration occur in _Z. princeps_, as pointed out
by Hall (1931:9). Yellow-sided dark-backed jumping mice exemplified by
_kootenayensis_, _idahoensis_, and _utahensis_ are found to the eastward
in the Rocky Mountains. Reddishbrown-sided, brown-backed jumping mice
typified by _luteus_ and _pacificus_ are found to the westward in the
Sierra Nevada and in New Mexico and Arizona; mice with yellowish-buff or
pinkish-buff-sides and light backs are the subspecies, _cinereus_,
_curtatus_, and _oregonus_, that occur in the intervening Great Basin.

External dimension as a whole decreases from north to south, although
not uniformly. For example, the smallest individuals are of the
southernmost geographic subspecies (_Z. p. luteus_), but the largest are
of the subspecies (_Z. p. utahensis_) that is near the geographic center
of the range for the species. In the skull there is geographic variation
in the length and shape of the zygomata, size and shape of the incisive
foramina, alignment of maxillary tooth-rows, size and shape of auditory
bullae, position of the postpalatal notch in relation to M3, and the
presence or absence and size of the medial projection on the inferior
ramus of the zygomatic process of the maxillary.


NATURAL HISTORY

_Habitat._--_Zapus princeps_ occurs most commonly adjacent to streams
where grasses and herbs are in lush growth. It frequents mountain
meadows neighboring small streams and is often taken from alder, aspen,
or stands of willow, where the moist ground supports a heavy undergrowth
of herbs. Davis (1939:330) found these mice in heavy herbage along a
small stream bordered by quaking aspen near Victor, Teton County, Idaho.
They were found along streams bordered by willow, rose, alder,
huckleberry, sedges, and herbs of various kinds at Alturas Lake, Mill
Creek, and at the head of the Pahsimeroi River. Linsdale (1938:195)
found jumping mice in the Toyabe Mountains, Nevada, near the streamsides
or in seepy areas close to the streams where associated vegetation
included rose, willow, wild peach, sage, grasses, and herbs. In the
Uinta Mountains, Utah, R. D. Svihla (1931:264) obtained them from
willows along streams in mountain parks. Borell and Ellis (1934:37) in
the Ruby Mountains, Nevada, found jumping mice to be common in heavy
vegetation along streams. Louise Kellogg (1916:369) obtained jumping
mice in northern California; all were near water, in grassy meadows, or
under alders where vegetation was dense.

_Zapus princeps_ is locally abundant, but its numbers seem to vary
considerably from year to year as well as seasonally. Early autumn, when
young of the year are abroad, seems to be the period of greatest
abundance. Moore (1928:154) remarks that runways were plainly marked and
well strewn with four-inch pieces of brome-grass. Davis (1939:334) notes
that _Z. princeps_ has runways, and found that sections, four inches
long, of cut grass piled in runways was good evidence of the presence of
the mouse.

_Behavior._--In reference to locomotion of _Z. princeps_, Davis (_loc.
cit._) writes, "In rapid progression jumping mice move by a series of
zigzag hops. One young of the year found in tall grass near Victor made
horizontal leaps of approximately three feet. The zigzag course was
difficult for me to follow, and I was led to wonder if this mode of
locomotion were not advantageous to the mice in eluding animals that
would do them harm." Hollister (1912:26) remarked that _princeps_, when
startled, sometimes jumps five to six feet at a bound. Concerning the
swimming ability of _Z. princeps_, Bailey (1936:233) quotes from
Hollister's notes, "While I was walking around the grassy border of a
small pond one jumped out at my feet and struck in the water like a
frog, which at first it was thought to be, until it was seen swimming
across the pond on the surface of the water ... he certainly handled
himself as if perfectly at home and swam with little effort and great
speed over the still surface of the pond." Davis (1939:334) obtained two
individuals at Mill Creek, Idaho, in traps placed on artificial islands
of stones in the middle of the creek where the water was about six
inches deep. He speculated that the only way the mice could have reached
the traps was by swimming. Grinnell, Dixon, and Linsdale (1930:531)
record an individual which was seen hopping in the inch-deep water of a
small stream at Lake Helen, California.

According to Hollister (1912:26) and Davis (1939:335), jumping mice are
for the most part nocturnal, but occasionally they are seen by day in
tall grass.

Little is recorded concerning the hibernation of _Z. princeps_. What
data are available suggest that, starting in July, these animals
accumulate a heavy layer of fat on the inside of the skin with
especially large amounts in the inguinal region. By August or early
September, animals are excessively fat, and the start of hibernation is
dependent then upon the arrival of a heavy cold snap. Grinnell, Dixon,
and Linsdale (1930:531), in their study of the vertebrates of the Lassen
Peak region of California noted that the latest activity by these mice
was September 13. As regards the time of onset of hibernation in Idaho,
Davis (1939:336) states that, "I know of no records of capture later
than September and infer that hibernation begins in that month or the
next." Bailey (1932:227) writes that in New Mexico, animals obtained on
September 20 were very fat, probably were ready to hibernate at the
first cold wave, and had winter nests in burrows well underground.

_Enemies._--Bailey (_loc. cit._) lists hawks, owls, and weasels as
natural predators on _Z. princeps_. Stanford (1931:362) records the
garter snake (_Thamnophis_) as a predator of jumping mice. A large snake
of this genus obtained by him regurgitated two jumping mice a few hours
after its capture. Grinnell, Dixon, and Linsdale (1937:232) report that
on Parker Creek, in California, H. C. Bryant frightened a weasel that
dropped a freshly killed jumping mouse. Crowe (1943:407) reported
_Cuterebra_ fly larvae in the inguinal region of a _Z. princeps_
obtained at Invermere, British Columbia. Several mice of this species
taken at Moccasin Lake, 19 mi. W and 4 mi. N of Lander, 10,000 ft.,
Fremont County, Wyoming, were heavily infested with mites of the family
Laelaptidae.

_Food._--In early September in central Utah, Moore (1928:154) found only
a white, starchy, glutinous paste in stomachs of six _Z. princeps_ and
only traces of a brown seed coat in a seventh. The main seeds eaten
seemed to be from an introduced brome-grass which was abundant in the
vicinity of capture. Bailey (1932:226) wrote of _Z. princeps_ in New
Mexico, that "In feeding they cut down the tall grass, beginning at the
bottom and cutting the stem at intervals as high as they can reach until
the seed part of the grass is brought down." He (_op. cit._:227)
remarked that the food was almost entirely seeds of grass and grasslike
plants and that the stomach contents almost always were perfectly clean
white dough from the shelled kernels of small seeds.

_Reproduction._--Females with embryos have been collected from late May
to mid-July and lactating individuals until late August. Possibly there
is only one litter per season as Davis (1939:336) suggests is the case
in Idaho.

Embryos in 25 pregnant females averaged 5 (2-7). The mammae of the
female are arranged in four pairs (two abdominal, one pectoral, and one
inguinal).

_Z. princeps_ builds a grass nest on the ground which is placed under
cover of vegetation or surface litter. Bailey (1932:227) writes that in
New Mexico jumping mice of this species use fibers of grass to construct
a ball-shaped nest. The nest usually has one opening but sometimes there
are two. In the Ruby Mountains, of Nevada, Borell and Ellis (1934:37)
found the globular nests of this mouse on the ground in tall grass.


=Zapus princeps cinereus= Hall

    _Zapus princeps cinereus_ Hall, Univ. California Publ. Zool., 37:7,
        April 10, 1931.

_Type._--Female, adult, skin and skull; No. 45422, Mus. Vert. Zool.;
Pine Canyon, 6600 feet altitude, Raft River Mountains, 17 mi. northwest
Kelton, Boxelder County, Utah; obtained on July 14, 1930, by Annie M.
Alexander; original No. 689.

_Range._--Raft River Mt's in northwestern Utah and in isolated mountains
in southern Idaho. See fig. 46. Zonal range: Transition and Canadian.

_Description._--Size, medium; back with broad mid-dorsal band, varying
from pale brown mixed with Pinkish-Buff to dark brown mixed with Warm
Buff or Ochraceous-Buff; sides varying from near Pinkish-Buff to near
Ochraceous-Buff; ventral surface white to base of hairs, not suffused
with other color; tail bicolored, pale brown above and white to
yellowish-white below; ears dark, edged with white or yellowish-white;
upper teeth divergent anteriorly; auditory bullae small; skull
relatively long; zygomata relatively weak and not widely bowed; nasals
wide posteriorly; pterygoid fossae relatively narrow.

_Comparisons._--From _Zapus princeps nevadensis_, _Z. p. cinereus_
differs as follows: Size averaging smaller; entire coloration lighter;
zygomata not so widely bowed; incisive foramina not so wide posteriorly;
auditory bullae smaller; nasals wider posteriorly; pterygoid fossae
narrower.

From _Zapus princeps idahoensis_, _Z. p. cinereus_ can be distinguished
by: generally paler color; smaller auditory bullae; broader interorbital
region; anteriorly diverging tooth-rows; narrower pterygoid fossae.

For comparison with _Zapus princeps utahensis_ see account of that
subspecies.

_Remarks._--Davis (1939:343) writes that "since _cinereus_ was described
from nine specimens, only two of which are near adult, one cannot place
much value on the coloration ascribed to it by Hall (1931:7)." I
examined the type series and found, as did Davis (_loc. cit._), that the
type is much lighter and grayer than is a near adult paratype, which was
obtained the same day; however, I do not concur with Davis (_loc. cit._)
that specimens from Mt. Harrison, 10 mi. S Albion, Idaho, which are
darker and much more ochraceous than the paratype, necessarily are more
nearly typically colored. These individuals, judged by cranial
characters, are more nearly typical of _cinereus_ but show
intergradation with _Z. p. idahoensis_ in their darker and more
ochraceous pelage.

Durrant (1952:387) found that the gray color of _Z. p. cinereus_ was not
diagnostic in separating _Z. p. cinereus_ from _Z. p. utahensis_,
because gray animals are also found in _Z. p. utahensis_. Specimens from
Camp Tendoy, Pocatello, Idaho, are intermediate in color and in cranial
characters as between _Z. p. idahoensis_ and _Z. p. cinereus_, but here
are referred to _Z. p. cinereus_. Whitlow and Hall (1933:268) compared
these individuals with specimens of _Z. p. princeps_ and _Z. p.
cinereus_, finding them intermediate but in the aggregate of several
differential characters better referred to the latter.

_Specimens examined._--Total, 35, distributed as follows:

IDAHO: _Bannock County_: Camp Tendoy, Pocatello, 2 (MVZ). _Cassia
County_: Mt. Harrison, 10 mi. S Albion, 16 (MVZ).

UTAH: _Boxelder Co._: _south fork of George Creek, 5 mi. SE Yost, Raft
River Mts., 6700 ft._, 1 (UU); _George Creek, 7 mi. SE Yost, Raft River
Mts., 6500 ft._, 6 (UU); _Pine Canyon, 6600 ft., 17 mi. NW Kelton, Raft
River Mts._, 8 (MVZ); Pine Creek, 3 mi. N Rosette, Raft River Mts., 6100
ft., 2 (UU).

_Marginal records._--Idaho: Camp Tendoy, Pocatello. Utah: Pine Creek, 3
mi. N Rosette, Raft River Mts., 6100 ft. Idaho: Mt. Harrison, 10 mi. S
Albion.


=Zapus princeps curtatus= Hall

    _Zapus princeps curtatus_ Hall, Univ. California Publ. Zool., 37:7,
        April 10, 1931.

    _Zapus princeps oregonus_, Taylor, Univ. California Publ. Zool.,
        7:281, June 24, 1911.

_Type._--Female, adult, skin and skull, No. 7991, Mus. Vert. Zool.; head
of Big Creek, 8000 feet altitude, Pine Forest Mountains, Humboldt
County, Nevada; obtained on June 30, 1909, by Walter P. Taylor and C. H.
Richardson, original No. 777 of W. P. T.

_Range._--Pine Forest Mt's, Humboldt County, Nevada. See fig. 46. Zonal
range: Transition and Canadian.

_Description._--Size medium; back pale near Light Ochraceous-Buff with
admixture of black hair forming dark dorsal band; sides lighter than
back; lateral line faintly indicated; ventral surface white; tail
bicolored, grayish-white to yellowish-white below and pale brown above;
ears dark, edged with yellowish-white; feet grayish-white above; palatal
bridge short; tooth-rows almost parallel; mastoid region of skull
relatively narrow; incisive foramina wide posteriorly; narrow across
zygomata; nasals relatively narrow posteriorly.

_Comparisons._--For comparison with _Zapus princeps oregonus_ see
account of that subspecies.

_Remarks._--This jumping mouse, which was described from the Pine Forest
Mountains, closely resembles _Zapus princeps oregonus_ but differs in
lighter color, slightly smaller body, less divergent tooth-rows,
shorter palate, and narrower skull across the mastoid region.

The Pine Forest Mountains are isolated from neighboring boreal regions
by a belt of the Upper Sonoran Life-zone, which is inhospitable to
_Zapus_; therefore, intergrades between _Z. p. oregonus_ and _Z. p.
curtatus_ are not known and probably do not exist. Nevertheless, _Z. p.
curtatus_ shows close affinity with _Z. p. oregonus_, as indicated by
Taylor (1911:281), and I agree with Hall (1931:7) that the relationships
of _Z. p. curtatus_ are best expressed by arranging it as a subspecies
of _Zapus princeps_.

_Specimens examined._--Total, 18, all from Nevada, distributed as
follows: _Humboldt County_: Pine Forest Mts.; Alder Creek, 6000 ft., 2
(MVZ); head of Big Creek, 8000 ft., 14 (MVZ); _Leonard Creek, 6500 ft._,
2 (MVZ); Meadow, 1 (MVZ).

_Marginal records._--Nevada: Pine Forest Mts., Alder Creek; Meadow.


=Zapus princeps idahoensis= Davis

    _Zapus princeps idahoensis_ Davis, Jour. Mamm., 15:221, August 10,
        1931.

    _Jaculus hudsonius_, Allen, Bull. Essex Inst., 6:61, April, 1874
        (part--the part in Carbon County, Wyoming).

    _Zapus hudsonius_, Merriam, N. Amer. Fauna, 5:72-73, July 30, 1891.

    _Zapus princeps princeps_, Preble, N. Amer. Fauna, 15:22-23, August
        8, 1899 (part).

_Type._--Male, adult, skin and skull; No. 54845, Mus. Vert. Zool.; 5 mi.
E Warm Lake, 7000 ft., Valley County, Idaho; obtained on July 9, 1932,
by Robert T. Orr; original No. 660.

_Range._--From Banff, Alberta, southward through extreme southwestern
Alberta and extreme southwestern British Columbia, most of the panhandle
of Idaho, Kamiak Butte in eastern Washington, western Montana, and
western Wyoming (Green, Wind River and Absoroka ranges of the Rocky
Mt's). See fig. 46.

_Description._--Size, medium; back from near Clay Color to near Warm
Buff, usually overlaid with black hairs forming broad dorsal band; sides
lighter than back; lateral line indistinct or wanting; belly pure white,
occasionally faintly tinged with Ochraceous-Buff; tail indistinctly
bicolored, tan to grayish-white below and pale brown above; hind feet
grayish-white above; ears dark, edged with white or yellowish-white;
postpalatal notch anterior to posterior border of last molars; proximal
part of inferior ramus of zygomatic process of maxillary relatively
narrow and usually without enlarged median projection; auditory bullae
well inflated; incisive foramina relatively narrow.

_Comparisons._--From _Zapus princeps kootenayensis_, _Z. p. idahoensis_
differs as follows: Size averaging larger; upper parts with greater
suffusion of ochraceous, not grayish or dusty; skull larger; incisive
foramina longer and relatively wider; zygomatic breadth averaging
greater; nasals broader at tips; auditory bullae more inflated.

From _Zapus princeps oregonus_, _Z. p. idahoensis_ differs in: Size
averaging smaller; upper parts generally more suffused with black hairs,
on the average more yellowish with less ochraceous; skull smaller;
incisive foramina narrower (breadth less, instead of more, than 52 per
cent of length); palatal bridge shorter; zygomatic arch shorter;
pterygoid fossae narrower.

From _Zapus princeps utahensis_, _Z. p. idahoensis_ can be distinguished
by: Size less; color slightly darker; skull averaging smaller in
zygomatic breadth, least interorbital constriction, and occipitonasal
length; palate narrower; upper tooth-rows nearly parallel as opposed to
diverging anteriorly.

From _Zapus princeps minor_, _Z. p. idahoensis_ differs in: Size larger;
color of underparts less ochraceous; lateral line indistinct or wanting;
skull averaging larger in all measurements taken except that the two
subspecies are approximately same in least interorbital constriction,
length of zygomatic arch, and distance from anterior face of incisors to
postpalatal notch; nasals, in profile, straight instead of with proximal
third depressed; postpalatal notch anterior to posterior face of last
molar, instead of even with, or usually posterior to, same.

From _Zapus princeps saltator_, _Z. p. idahoensis_ differs as follows:
Size averaging slightly larger; color darker, being less ochraceous and
more yellow dorsally and laterally; auditory bullae more inflated;
zygomatic arches less bowed laterally; incisive foramina narrower.

For comparison with _Zapus princeps princeps_ and _Zapus princeps
cinereus_ see accounts of those subspecies.

_Remarks._--Intergradation occurs at almost all of the places where the
range of _Z. p. idahoensis_ is known to touch that of any other
geographic race. Nevertheless, each of the populations studied has
characters which make this subspecies recognizable as a taxonomic unit,
although its characters are not yet stabilized even in the central part
of its range.

Among named subspecies of _Zapus princeps_, _Zapus p. idahoensis_ most
closely resembles _Zapus princeps kootenayensis_, its nearest geographic
neighbor to the north. Three specimens from 2 mi. NE Weippe, 3000 ft.,
Idaho, are best referred to _Z. p. idahoensis_ but show relationship to
_Z. p. kootenayensis_ in size and shape of the tympanic bullae. The
relationship of individuals from Idaho, here referred to _Z. p.
idahoensis_, from Glidden Lakes, Enaville, Cascade Creek, and 13 mi. E
and 5 mi. N Coeur d'Alene, is discussed in the account of _Z. p.
kootenayensis_. British Columbian specimens from Newgate and Crows Nest
Pass, 4450 ft., as well as Albertan specimens from Crows Nest Pass and
various places in Waterton Lake Park, resemble _Z. p. kootenayensis_ in
color but cranially are more nearly like _Z. p. idahoensis_.

Intergradation with _Zapus princeps oregonus_ was noted by Davis
(1939:340) in a specimen from Cedar Mountain in Idaho. I have not seen
this individual which he referred to _Z. p. idahoensis_ but have seen a
specimen from the N Fork of Potlatch River (15 mi. SE Cedar Mt.), which,
in color, closely resembles _Z. p. oregonus_ but cranially (shape of
incisive foramina, size, and inflation of auditory bullae) is more
nearly like _Z. p. idahoensis_ to which it is referred. Davis (_loc.
cit._) indicates that specimens from summit of Smith Mt., from 1 mi. N
Bear Creek R. S., from 1/2 mi. E Black Lake, and from 3 mi. W Payette
Lake, Idaho, are in an area of intergradation between _Z. p. oregonus_
and _Z. p. idahoensis_, but he referred them to _Z. p. idahoensis_ on
the basis of cranial characters and length of hind foot. Seven specimens
from Alturas Lake, 7000 ft., Idaho, were likewise so allocated by Davis
(_loc. cit._). I concur with him and in addition refer the following
intermediate individuals from Idaho to _Z. p. idahoensis_: New Meadow,
1; Warren, 1; Perkins Lake, 7000 ft., Sawtooth Nat'l Forest, 1; Prairie
Creek, 12 mi. W Ketchum, 2400 ft., 3. All are more nearly like _Z. p.
oregonus_ in color but cranially they show more resemblance to _Z. p.
idahoensis_.

In the eastern part of the range of _Z. p. idahoensis_, intergradation
occurs with _Zapus princeps minor_, as at 15 mi. S Heath, N Fork Flat
Willow Creek, Big Snowy Mt's, Montana. Specimens from there have the
lateral line enlarged and the maximum seen in this species of Ochraceous
color ventrally. The pterygoid fossae are large and the bullae are
reduced as in _Z. p. minor_, but in the sum total of the characters the
mice more closely resemble _Z. p. idahoensis_. At Lewistown, 7 mi. NE
Judith Mt's, Lime Kiln Gulch, Montana, the animals are colored as are
_Z. p. minor_ but cranially are like _Z. p. idahoensis_ to which they
are referred. Specimens from the Highwood Mt's, Montana, also are
intergrades; they have a relatively distinct lateral line as in _Z. p.
minor_ but show no ventral suffusion of Ochraceous; they have large
bullae, nasals that are straight in lateral profile and other cranial
characters of _Z. p. idahoensis_ to which they are here referred.

A single specimen from Kamiak Butte, Whitman County, Washington, has
been referred to _Z. p. idahoensis_ by Dalquest (1948:373). I have not
seen this individual, but, on geographic grounds, it is likely to be of
this subspecies.

_Specimens examined._--Total, 342, distributed as follows:

ALBERTA: Boom Creek, 5600 ft., 27 mi. W Banff, 2 (NMC); _Banff, Cascade
Basin_, 2 (NMC); _Bryant Creek, Banff Park_, 1 (NMC); _Spray River, 7
mi. Cabin, Banff Park_, 3 (NMC); Crows Nest Pass, 2 (NMC); Waterton
Lakes Park, 16 (NMC); _Linnets Pond, Waterton Lakes Park_, 4 (NMC);
_Bertha Creek, Waterton Lakes Park_, 8 (NMC).

BRITISH COLUMBIA: Vermilion Crossing, Kootenay, 1 (ROM); Paradise Mine,
3 (PM); Crows Nest Pass, 4450 ft., 3 (NMC); Newgate, 10 (NMC).

IDAHO: _Adam Co._: 1/2 mi. E Black Lake, 6800 ft., 8; _summit of Smith
Mtn., 7500 ft._, 9 (3 MVZ); 1 mi. N Bear Creek R. S., SW Slope Smith
Mtn., 5400 ft., 13; New Meadows, 1 (USBS); _3 mi. W Payette, 5400 ft._,
4 (MVZ). _Blaine County_: _Perkins Lake, 7000 ft., Sawtooth Nat'l
Forest_, 1; _Alturas Lake, 7000 ft._, 3 (MVZ); Prairie Creek, 12 mi. NW
Ketchum, 2400 ft., 3. _Clearwater County_: 2 mi. NE Weippe, 3000 ft., 3
(MVZ). _Custer County_: Loon Creek R. S., 6000 ft., Challis Nat'l
Forest, 2; _Head Pahsimeroi River_, 2 (MVZ); Mill Creek, 14 mi. WSW
Challis, 8370 ft., 1 (MVZ). _Fremont County_: 7 mi. W West Yellowstone,
7000 ft., 3; _17 mi. E and 4 mi. N of Ashton, 6275 ft._, 9 (MVZ). _Idaho
Co._: Packers Meadow, near state line, South Lobo Hot Springs, 5150 ft.,
7 (USBS); _Warren_, 1 (USBS). _Kootenai Co._: 13 mi. E and 5 mi. N Coeur
d'Alene, 5; _Cascade Creek, 36 mi. E Coeur d'Alene, Coeur d'Alene Nat'l
Forest_, 1 (USBS). _Latah Co._: N Fork Potlatch River, 1 (USBS). _Lemhi
County_: Salmon River Mts., 3 (USBS). _Shoshone Co._: Enaville 1 (USBS);
_Glidden Lakes, 5700 ft._, 4 (MVZ). _Valley County_: 5 mi. E Warm Lake,
7000 ft., 6 (MVZ); _5 mi. W Cape Horn, 7000 ft., Sawtooth Range_, 1
(MVZ).

MONTANA: _Beaverhead County_: Birch Creek, 18 mi. NE Dillon, 7100 ft.,
14 (MVZ). _Carbon Co._: _Pryor Mts._, 1 (USBS); 2 mi. E Shriver, 6500
ft., 6 (MVZ). _Cascade Co._: Neihart, 1 (USBS). _Chouteau Co._: _Upper
Muddy_, 1 (USBS); Highwood Mts., 2 (USBS). _Fergus Co._: Lime Kiln
Gulch, 7 mi. NE Judith Mts., 3 (USBS); 15 mi. S Heath, N Fork Flat
Willow Creek, 8 (USBS); _10 mi. W Tyler, N Fork Flat Willow Creek_, 1
(USBS); _Crystal Lake, 6000 ft., Big Snowy Mts._, 3 (UM). _Flathead
Co._: Waterton Lake, 1 (USBS); _Crosley Lake, Glacier Nat'l Park_, 1
(USBS); Paola, 1 (USBS); _Summit_, 2 (USBS); _1 mi. W and 2 mi. S
Summit, 5000 ft._, 12. _Gallatin Co._: 4 mi S Logan, Camas Creek, Big
Belt Mts., 5 (USBS); Gallatin Gateway, 5 (SDM); west fork West Gallatin
River, 6500 ft., 6 (USBS). _Glacier Co._: Babb, 1 (LMH); _2-1/2 mi. W
and 1-1/2 mi. S Babb, 4700 ft._, 1; _Many Glaciers, 4900 ft., Glacier
Nat'l Park_, 5 (MVZ); _6 mi. S St. Marys, 6500 ft._, 1; _St. Marys
Lake_, 7 (USBS); _McDermit Lake_, 1 (USBS); Blackfoot Agency, 1 (USBS).
_Golden Valley County_: _Swimming Woman Canyon, 3/4 mi. S Fergus County
line, Big Snowy Mts._, 4 (UM). _Judith Basin Co._: _Little Belt Mts.,
Dry Wolf Creek, 20 mi. SW Stanford_, 4 (USBS); 13 mi. W Buffalo, 1
(USBS). _Madison Co._: 12 mi. SW Alder, Hinch Creek, Ruby Mts., 2
(USBS). _Meagher Co._: _16 mi. N White Sulphur Springs, Little Belt
Mts._, 7 (USBS). _Park County_: _West Boulder Creek, 18 mi. SE
Livingston_, 1 (USBS); Emigrant Gulch, 3 mi. SE Chico, 6500 ft., 4
(USBS); 2 mi. NE Cooke, 8000 ft., 22 (MVZ). _Ravalli County_: 3 mi. SW
Florence, 3700 ft., 1; 6 mi. E Hamilton, 3700 ft., 1. _Sanders Co._:
Prospect Creek, near Thompson, 1 (USBS). _Sweet Grass Co._: _near head
of Big Timber Creek, 5200 ft., Crazy Mts._, 11 (USBS); Brannin Ranch,
Sweet Grass Creek Canyon, 6 (UM); _Big Timber_, 1 (USBS). _Teton
County_: 17-1/2 mi. W and 6-1/2 mi. N Agusta, 5100 ft., 2.

WYOMING: _Fremont County_: Moccasin Lake, 19 mi. W and 4 mi. N of
Lander, 10,000 ft., 1; 23-1/2 mi. S and 5 mi. W Lander, 8600 ft., 4.
_Park County_: 31-1/2 mi. N and 36 mi. W Cody, 6900 ft., 7; _28 mi. N
and 30 mi. W Cody, 7200 ft._, 1; _16-1/4 mi. N and 17 mi. W Cody, 5625
ft._, 14; 2 mi. S and 42 mi. W Cody, 6400 ft., 5; 12 mi. W Wapiti, 6
(LMH); _25 mi. S and 28 mi. W Cody, 6350 ft._, 5. _Sublette County_: E
end Island Lake, 10,600 ft., 3 mi. S Fremont Park, 1; _N side Halfmoon
Lake, 7900 ft._, 3; _W end Halfmoon Lake, 7900 ft._, 2; _10 mi. NE
Pinedale, 8000 ft._, 1; _5 mi. E and 8 mi. N Pinedale, 7500 ft._, 1; 3
mi. E and 5 mi. N Pinedale, 7500 ft., 4; 19 mi. W and 2 mi. S Big Piney,
7700 ft., 3.

_Marginal records._--Alberta: Boom Creek, 5600 ft., 27 mi. W Banff;
Crows Nest Pass; Waterton Lakes Park. Montana: Highwood Mts.; 15 mi. S
Heath, N Fork Flat Willow Creek; 2 mi. E Shriver, 6500 ft. Wyoming:
23-1/2 mi. S and 5-1/2 mi. W Lander, 8600 ft.; 10 mi. W and 2 mi. S Big
Piney, 7700 ft. Idaho: 7 mi. W West Yellowstone, 7000 ft.; Prairie
Creek, 12 mi. NW Ketchum, 2400 ft.; 5 mi. W Warm Lake, 7000 ft.; 1 mi. N
Bear Creek R. S., SW slope Smith Mtn., 5400 ft.; N Fork Potlatch River;
13 mi. E and 5 mi. N Coeur d'Alene. British Columbia: Newgate; Vermilion
Crossing, Kootenay.


=Zapus princeps kootenayensis= Anderson

    _Zapus princeps kootenayensis_ Anderson, Ann. Rept. Nat. Mus.
        Canada for 1931:108, November 24, 1932.

    _Zapus princeps princeps_, Preble, N. Amer. Fauna, 15:23, August 8,
        1899 (part).

_Type._--Adult female, skin and skull, No. 10,020, Nat. Mus. Canada;
near summit of Green Mountain, head of Murphy Creek, about 10 miles
north of Rossland, West Kootenay district, British Columbia, at about,
6000 ft.; latitude 49° 13' north, longitude 117° 52' west; obtained on
July 18, 1929, by R. M. Anderson, original No. 24.

_Range._--From Glacier in the Selkirk Range, British Columbia, south to
5 mi. W Cocolalla, Bonner County, Idaho, west and north to Sullivan
Lake, Pend Oreille County, Washington; and northwestward to Manning Park
on the eastern summit of the Cascade Range in British Columbia. See fig.
46.

_Description._--Size, medium; color moderately dark; upper parts
noticeably dull and dusty; broad dorsal band of dull Ochraceous-Buff to
near Warm Buff sprinkled with black hair to a varying degree, resulting
in two color phases (dark has more black hair; Ochraceous phase or Warm
Buff phase has more brown hair); sides paler than back owing to fewer
black hairs; lateral line, when present, narrow and dull; ventral
surface pure white; tail bicolored, pale brown above, yellowish-white to
dull white below; ears dark with narrow white or yellowish-white
edgings; feet white above; skull narrow across zygomata; incisive
foramina narrow; bullae moderately inflated; nasals narrow at tips;
postpalatal notch anterior to posterior face of last molars; braincase
moderately narrow; zygomatic arch short.

_Comparisons._--From _Zapus princeps saltator_, _Z. p. kootenayensis_
differs as follows: Upper parts generally dull with less ochraceous;
sides with more yellow, less ochraceous; lateral line wanting or not
bright; skull averaging slightly smaller; incisive foramina smaller and
narrower posteriorly; small medium projection on inferior ramus of the
zygomatic process of maxillary frequently present instead of absent;
pterygoid fossae shorter and narrower.

For comparison with _Zapus princeps idahoensis_ see account of that
subspecies.

_Remarks._--This subspecies is paler and averages smaller than either of
the subspecies with adjoining geographic ranges. There is intergradation
with _Zapus princeps idahoensis_ in color, shape and size of incisive
foramina, and in the shape of the nasals in Idaho-taken specimens from
Glidden Lakes and Enaville. These individuals are thought to be _Z. p.
idahoensis_. Specimens from the same state taken at Cascade Creek and 13
mi. E and 5 mi. N Coeur d'Alene show intergradation in color, size and
inflation of bullae, configuration of nasals, and shape of the vomer
between _Zapus princeps idahoensis_ and _Z. p. kootenayensis_. The
majority of characters studied show these animals to be referable to _Z.
p. idahoensis_.

Specimens from Monashee Pass, 4000 ft., British Columbia, show
relationship to _Zapus princeps saltator_ in the posteriorly wide
incisive foramina, in the narrow vomer, and, in some individuals, in the
increased amount of ochraceous, dorsally and laterally. The majority of
characters studied show these animals to be referable to _Z. p.
kootenayensis_.

The animals available from Glacier, British Columbia, are in color more
nearly like _Z. p. saltator_ and cranially combine the characters of _Z.
p. idahoensis_, _Z. p. saltator_, and _Z. p. kootenayensis_. The sum
total of their characters places them with _Z. p. saltator_. Anderson
(1932:108) remarks on the disparity of size between the two sexes of _Z.
p. kootenayensis_, stating that females are considerably larger than
males. I have examined most of the material used in the original
description and find that animals of like age in the two sexes show no
significant size difference. Anderson (_loc. cit._) seems to have
compared young males with adult females.

_Specimens examined._--Total, 68, distributed as follows:

BRITISH COLUMBIA: Manning Park, 3 (PM); _Good Fellow Creek, Manning
Park_, 1 (PM); _Mt. Beaver Valley, 6300 ft., Manning Park_, 1 (PM);
_Timberline Valley, 6500 ft._, 3 (PM); _Allison Pass, 1 mi. E Manning
Park_, 1 (PM); Monashee Pass, 4000 ft., 13 (PM); Hope-Princeton Summit,
5500 ft., 1 (NMC); _Hedley, Stirling Creek_, 1 (NMC); Anarchist Mts., 1
(PM); Fairview-Keremeos Summit, 5 (NMC); _Westbridge_, 2 (NMC);
_Midway_, 2 (NMC); Green Mtn., near Rossland, 6000 ft., 12 (11 NMC, 1
MVZ); _Mt. Old Glory, 7000 ft., Rossland_, 5 (4 NMC, 1 MVZ); _Rossland,
5800 ft._, 12 (11 NMC, 1 MVZ); Camp 6, Meadow Creek, 7 mi. SE of Yahk, 1
(NMC).

IDAHO: _Bonner County_: 5 mi. W Cocolalla, 3500 ft., 2 (MVZ). _Boundary
County_: 4 mi. W Meadow Creek, 3000 ft., 2 (MVZ).

_Marginal records._--British Columbia: Monashee Pass, 4000 ft.; Camp 6,
Meadow Creek, 7 mi. SE Yahk. Idaho: 4 mi. W Meadow Creek, 3000 ft.; 5
mi. W Cocolalla, 3500 ft. British Columbia: Hope-Princeton Summit, 5500
ft.; Manning Park.


=Zapus princeps luteus= Miller

    _Zapus luteus_, Miller, Proc. Biol. Soc. Washington, 24:253,
        December 23, 1911.

    _Zapus luteus australis_, Bailey, Proc. Biol. Soc. Washington,
        26:132, May 21, 1913. Type from Socorro, Socorro County,
        New Mexico.

_Type._--Female, adult, skin and skull, No. 133601, U. S. Nat. Mus.
Biol. Surv. Coll., Espanola, 5000 ft., Rio Arriba Co., New Mexico;
obtained on June 24, 1904, by McClure Surber, original No. 162.

_Range._--White Mt's of southern Apache County and northern Greenlee
County, Arizona; in New Mexico, from the Sacramento Mt's, Otero County,
northward to the San Juan Mt's, Rio Arriba County. See fig. 46. Zonal
range: Lower Sonoran (1 individual), Upper Sonoran, Transition, and
Canadian.

_Description._--Size, small; back near Ochraceous-Buff, having black
hair interspersed; mid-dorsal band not always well marked; sides
Ochraceous-Buff with fine admixture of black hair; lateral line blending
with Ochraceous-Buff of sides, not distinct; ventral surface white to
base of hairs, in some cases lightly suffused with color of sides; tail
indistinctly bicolored, tan to grayish-white below and brown above; hind
feet grayish-white above; ears brownish, narrowly edged with
Ochraceous-Buff; skull small; antorbital foramina relatively large;
interorbital region broad; inferior ramus of the zygomatic process of
the maxillary broad, often with medial projection; incisive foramina
narrow posteriorly becoming broadly rounded anteriorly; palatal bridge
relatively long; pterygoid fossae narrow; zygomatic arches relatively
robust; nasals tapering at each end.

_Comparisons._--From _Zapus princeps princeps_, _Z, p. luteus_ differs
as follows: Size, smaller; color lighter, more Ochraceous-Buff; ears
lighter, edged with Ochraceous-Buff as compared with white or
yellowish-white; lateral line indistinct or wanting as opposed to
distinct; dorsal stripe not well defined; interorbital region broader;
antorbital foramina relatively larger; zygomatic arches more robust;
nasals tapering at each end as opposed to parallel sided; auditory
bullae smaller, less inflated.

_Remarks._--The characters of this subspecies are relatively stable
throughout most of its geographic range. Hall and Davis (1934:56)
remarked that their material from the White Mountains of Arizona
answered precisely to Miller's original description (1911:253) of the
species, and my examination of these and other specimens from that area
indicates the same thing except that the specimens average slightly
darker mid-dorsally than those from New Mexico.

_Zapus luteus australis_, based on a single individual taken in a
riparian thicket along the Rio Grande at Socorro, New Mexico, is
referable to _Z. p. luteus_. The diagnostic characters, referred to in
the original description, are as follows: Small, slender, and very
narrow skull; especially narrow braincase; slender rostrum; and light
dentition. These are expressions of age, rather than of geographic
variation, in that the individual is a subadult (young of the year). The
color, which is paler than in adults of _Z. p. luteus_, is almost
identical with that of a subadult (No. 205585 USBS) from Alpine,
Arizona. I can see no basis for recognition of _Z. p. australis_ and the
name, therefore, is placed as a synonym of _Z. p. luteus_.

Four specimens from 4 mi. NE El Rito, 7000 ft., New Mexico, show
intergradation, in the shape of the nasals and incisive foramina, in the
robustness of the zygomatic arch, and in the breadth of the braincase
with a specimen of _Zapus princeps princeps_ from Tierra Amarilla, New
Mexico. In color and in external measurements as well as in other
cranial characters they closely agree with typical _Z. p. luteus_ and
are here referred to the latter.

_Specimens examined._--Total, 49, distributed as follows:

ARIZONA: _Apache Co._: North Fork White River, White Mts., 24 (SDM);
Alpine, 8500 ft., 6 (USBS); West Fork Black River, 7700 ft., 8 (MVZ);
_Greenlee County_: Hannagan Creek, 8200 ft., 2 (MVZ).

NEW MEXICO: _Otero Co._: 12 mi. E Cloudcroft, 7500 ft., 2 (USBS). _Rio
Arriba Co._: 4 mi. NE of El Rito, 7000 ft., 4; Espanola, 5000 ft., 2
(USBS). _Socorro Co._: Socorro, 1 (USBS).

_Marginal records._--New Mexico: 4 mi. N El Rito, 7000 ft.; Espanola,
5000 ft.; 12 mi. E Cloudcroft, 7500 ft. Arizona: Hannagan Creek, 8200
ft.; W. Fork Black River, 7700 ft.; N. Fork White River, White Mts. New
Mexico: Socorro.


=Zapus princeps minor= Preble

    _Zapus princeps minor_ Preble, N. Amer. Fauna, 15:23, August 8,
        1899.

    _Zapus hudsonius campestris_, Bailey, N. Amer. Fauna, 49:117,
        January 8, 1927 (part).

_Type._--Adult female, skin and skull, No. 73673, U. S. Nat. Mus. Biol.
Surv. Coll., Wingard, near Carlton House, Saskatchewan; obtained on July
23, 1895, by J. Alden Loring, original No. 3123.

_Range._--Most of southern half of Saskatchewan and Alberta,
northeastern Montana southeastward to Aweme, Manitoba, and Webster,
South Dakota. See fig. 46. Zonal range: Transition, Hudsonian, and
Canadian.

_Description._--Size, small; back dark, usually with a distinct
mid-dorsal band of black mixed with Warm Buff; sides lighter, more
yellowish, but always with an admixture of black hairs; lateral line
distinct, near Ochraceous-Buff, ventral surface characteristically
suffused with Ochraceous-Buff; tail bicolored, grayish-white to
yellowish-white below and pale brown above; hind feet grayish-white
above; ears dark, edged with white or yellowish-white; skull small;
postpalatal notch often anterior to posterior part of molars; inferior
ramus of zygomatic process of maxillary often with well developed medial
projection; auditory bullae flattened; nasals narrower anteriorly and
proximal third depressed; base of zygomatic process of squamosal broad.

_Comparisons._--From _Zapus princeps princeps_, _Z. p. minor_ differs as
follows: Size averaging smaller in all measurements taken, except least
interorbital constriction which is approximately the same; color
dorsally and laterally more yellowish, less Ochraceous-Buff; ventrally
greater suffusion of Ochraceous-Buff.

For comparison with _Zapus princeps idahoensis_ see account of that
subspecies.

_Remarks._--This geographic race is notably stable and retains most of
its diagnostic characters throughout nearly all parts of its range.
Intergradation occurs with _Zapus princeps idahoensis_ at various
localities in Montana, as is described in more detail in the account of
_idahoensis_. Crowe (1943:406) gives evidence of intergradation between
_Zapus princeps idahoensis_ and _Z. p. minor_ in specimens from Entrance
in western Alberta. Crowe (_loc. cit._) described these individuals as
intermediate in color (lateral line present, under parts washed with
buff, sides and dorsal stripe rich in ochraceous), and in cranial
characters (smaller skulls, anteriorly narrower nasals, shorter more
deflected rostrum, and higher cranium); but he considered them closer to
_Z. p. minor_.

A skin without skull from Kananaskis Valley, Alberta, shows
intergradation between _Z. p. idahoensis_ and _Z. p. minor_. This
individual is like _Z. p. idahoensis_ in dorsal and lateral coloring,
but is nearer _Z. p. minor_ in ventral coloring and in the presence of a
distinct lateral line. External measurements provide basis for
tentatively assigning the skin to _Z. p. minor_.

_Specimens examined._--Total, 118, distributed as follows:

ALBERTA: 4 mi. N Marinville, 2; Blindman River, 1 (USBS); Camrose, 1
(ROM); Red Deer River, 1 (USBS); Didsbury, Little Red Deer River, 1
(ROM); Kananaskis Valley, 7000 ft., 1 (ROM); High River, 2 (ROM); Lodge
Creek, 2 (NMC).

MANITOBA: Shoal Lake, 6 (NMC); Oak Lake, 4 (NMC); Aweme, 7 (6 ROM; 1
USBS).

MONTANA: _Chouteau County_: Eagle Creek, 25 mi. SE Big Sandy, 3 (UM).
_Hill Co._: Fort Assiniboine, 1 (USBS); _Bear Paw Mt's, 20 mi. SE Fort
Assiniboine_, 4 (USBS); _head Eagle Creek, Bear Paw Mt's_, 7 (UM).
_Valley Co._: Glasgow, 1 (USBS).

NORTH DAKOTA: _Benson Co._: 4 mi. W Leeds, 1400 ft., 2; _2 mi. W Fort
Totten, 1400 ft._, 13; Fort Totten, 4 (USBS). _Bottineau Co._: 4-8/10
mi. N Bottineau, 2100 ft., 2; _3-1/2 mi. N Bottineau, 1920 ft._, 2;
_2-1/10 mi. N Bottineau, 1800 ft._, 3; _Bottineau_, 1 (USBS). _Dickey
Co._: Oakes, 3 (USBS). _Grand Forks Co._: Larimore, 3 (USBS). _Montrail
Co._: 6 mi. N Lostwood, 2 (USBS). _Nelson Co._: Stump Lake, 1 (USBS).
_Richland Co._: _Lidgerwood_, 1 (USBS); 4 mi. S Blackner, (USBS).
_Rolette Co._: St. John, 1 (USBS). _Sargent County_: _7-1/5 mi. E and
1-1/5 mi. S Oakes, 1200 ft._, 6; _3 mi. W Cayuga, 1000 ft._, 2. _Walsh
Co._: Grafton, 2. _Ward Co._: _Minot_, 3 (CMNH). _Williams Co._:
Grinnell, 2 (USBS); Buford, 2 (USBS).

SASKATCHEWAN: Wingard, near Carlton House, 2 (USBS); Fort Carlton, 1
(MVZ); Indian Head, 2 (USBS); Cypress Hills, N Maple Creek, 18 (NMC);
_Battle Creek_, 1 (NMC).

SOUTH DAKOTA: _Day Co._: Webster, 1 (Chic. AS).

_Marginal records._--Saskatchewan: Wingard, near Carlton House; Fort
Carlton. Manitoba: Shoal Lake; Aweme. North Dakota: Larimore; 4 mi. S
Blackner. South Dakota: Webster. North Dakota: Oakes; Grinnell. Montana:
Eagle Creek, 25 mi. SE Big Sandy. Alberta: High River; Kananaskis
Valley, 2000 ft.; Red Deer River; Blindman River; 4 mi. N Marinville.


=Zapus princeps oregonus= Preble

    _Zapus princeps oregonus_ Preble, N. Amer. Fauna, 15:24, August 8,
        1899.

    _Zapus major_ Preble, N. Amer. Fauna, 15:24, August 8, 1899, type
        from Warner Mt's, Lake County, Oregon.

    _Zapus princeps major_, Hall, Univ. California Publ. Zool., 37:10,
        April 10, 1931.

    _Zapus nevadensis_ Preble, N. Amer. Fauna, 15:25, August 8, 1899,
        type from Ruby Mt's, Elko County, Nevada.

    _Zapus princeps nevadensis_, Hall, Univ. California Publ. Zool.,
        37:10, April 10, 1931.

    _Zapus princeps palatinus_ Hall, Univ. California Publ. Zool.,
        37:8, April 10, 1931, type from Wisconsin Creek, 7800 ft.,
        Toyabe Mt's, Nye County, Nevada.

    _Zapus princeps princeps_, Anthony, Bull. Amer. Mus. Nat. Hist.,
        33:17, March 17, 1913.

_Type._--Male, adult, skin and skull; No. 78156, U. S. Nat. Mus. Biol.
Surv. Coll.; Elgin, Blue Mountains, Union Co., Oregon; obtained on May
29, 1896, by Edward A. Preble, original No. 959.

_Range._--Southeastern Washington, eastern Oregon east of Cascades,
northeastern California, central and northeastern Nevada, and
southwestern Idaho. See fig. 46. Zonal range: Transition and Canadian.

_Description._--Size large; back from near Light Ochraceous-Buff to near
Cinnamon-Buff, usually overlaid with black hairs forming broad dorsal
band, which in some individuals is almost black; sides lighter than
back, from near Light Pinkish-Cinnamon to near Cinnamon-Buff and
Ochraceous-Buff, often with black hairs interspersed; lateral line
faintly marked or wanting; belly pure white; tail bicolored,
grayish-brown above and grayish-white to yellowish-white below; ears
dark, edged with color of sides; palatal bridge long; interorbital
region broad; inferior ramus of zygomatic process of maxillary usually
with median projection; auditory bullae relatively small; incisive
foramina greatly enlarged posteriorly; tooth-rows divergent anteriorly;
nasals narrow posteriorly.

_Comparisons._--From _Zapus princeps curtatus_, _Z. p. oregonus_ differs
as follows: Size averaging larger; upper parts darker; tooth-rows more
divergent anteriorly; palatal bridge longer; mastoid region broader;
incisive foramina relatively wider posteriorly.

For comparisons with _Zapus princeps cinereus_, _Zapus princeps
pacificus_ and _Zapus princeps idahoensis_ see accounts of those
subspecies.

_Remarks._--The coloration in _Z. p. oregonus_ varies somewhat from
north to south. In the northern part of the range the average coloration
of the upper parts is darker with more ochraceous on the sides. To the
southward the upper parts are progressively paler and the sides are near
Light Pinkish-Cinnamon. Because of this variation of color, and because
of the small samples available to workers in the past, three populations
of this subspecies have been named as distinct. However, with the large
amount of additional material now available, the supposed diagnostic
characters of these "forms" prove to be within the range of individual
variations of each of several populations of which large samples are
available.

_Zapus major_ Preble (1899:24) was described as having zygomata short,
palate broad and long, incisive foramina large and elliptical, and color
dark. Some specimens of _Z. p. oregonus_, from nearly all parts of its
geographic range, show these same characters. Resemblances in anteriorly
divergent tooth-rows, broad interorbital region, small auditory bullae,
and posteriorly narrow nasals, are additional reasons for placing _Z.
major_ as a synonym of _Z. p. oregonus_.

_Zapus nevadensis_ Preble (1899:25), here considered a synonym of _Z. p.
oregonus_, was described as having: auditory bullae small, posterior
border of the palate usually convex anteriorly, palatal bridge long, and
color pale. These characters, however, are within the range of
individual variation of _Zapus p. oregonus_. Similarities such as
tooth-rows diverging anteriorly, nasals narrow posteriorly, interorbital
region broad, and incisive foramina enlarged posteriorly are added
reasons for placing _Z. nevadensis_ as a synonym of _Z. p. oregonus_.

_Zapus princeps palatinus_ Hall (1931:8) was described as having:
palatal bridge long, incisive foramina wide posteriorly, posterior
border of palate straight or convex posteriorly, and color pale. These
characteristics are to be found in some individuals in most populations
of _Z. p. oregonus_. Additional well marked cranial similarities, such
as small auditory bullae, broad interorbital region, and nasals narrow
posteriorly offer additional evidence as to the close relationship of
_Z. p. palatinus_ and _Z. p. oregonus_. Hall (_loc. cit._), with a small
sample available to him for comparative purposes (14 specimens of _Z. p.
palatinus_ and 12 specimens of _Z. p. nevadensis_), was impressed by
the condition of the palate in _Z. p. palatinus_ and wrote: "the
generally straight, or even posteriorly convex, posterior border of the
palate seems to be unique among described forms of _Zapus_. The name
_palatinus_ is given in allusion to this structural feature." With more
than 300 specimens of _Z. p. oregonus_ available for study I find that a
straight or posteriorly convex posterior border of the palate occurs in
more than 50 per cent of the individuals examined. Specimens displaying
this described palatal condition are known from all parts of the range
of _Z. p. oregonus_, but do occur in a higher percentage of specimens in
the area ascribed by Hall (_loc. cit._) to the range of _Z. p.
palatinus_.

Intergradation with _Zapus princeps idahoensis_ and _Zapus princeps
cinereus_ is discussed in the accounts of those subspecies.

_Specimens examined._--Total, 340, distributed as follows:

CALIFORNIA: _Modoc Co._: Buck Creek R. S., 1 (CAS); _Willow Ranch_, 4
(CAS); _Sugar Hill, 5000 ft._, 1 (MVZ); _Goose Lake Meadows, near Sugar
Hill_, 4 (MVZ); _Parker Creek, Warner Mts., 5500 ft._, 18 (MVZ); _Dry
Creek, Warner Mts., 4800 ft._, 3 (MVZ) _east face Warner Peak, Warner
Mts., 8700 ft._, 1 (MVZ); _5 mi. NW Eagle Peak, 7000 ft._, 5 (MVZ);
Lassen Creek, 1 (SDM); _Happy Camp_, 1 (CAS).

IDAHO: _Boise Co._: Bald Mtn. R. S., Boise Nat'l Forest, 10 mi. S. Idaho
City, 7400 ft., 2 (USBS). _Elmore Co._: Trail Creek, Boise Nat'l Forest,
2 (USBS). _Washington County_: 1 mi. NE Heath, SW Slope Cuddy Mtn., 4000
ft., 20 (5 MVZ).

NEVADA: _Elko County_: _6 mi. SW Mountain City, Cobb Creek, 6500-6550
ft._, 44 (MVZ); _summit between heads of Copper and Coon creeks,
Jarbidge Mts._, 18 (9 MVZ); _head of Ackler Creek, 6800 ft._, 2: Steel
Creek, 7000 ft., 11 (4 MVZ); _summit of Secret Pass, 6200 ft._, 8;
_south fork Long Creek, 7830 ft._, 4; Harrison Pass R. S., Green Mtn.,
Canyon, 6050 ft., 12. _Eureka County_: 4 mi. S Tonkin, Denay Creek,
Roberts Mt's, 1 (MVZ). _Humboldt County_: _Martin Creek R. S._, 1 (MVZ);
13 mi. N Paradise Valley, 6700 ft., 19 (MVZ). _Lander County_: Kingston
R. S., 7500 ft., 4 (MVZ). _Nye County_: Wisconsin Creek, 7000 ft., 12
(MVZ). _White Pine County_: Willow Creek, 2 mi. S Elko County line, Ruby
Mts., 6500 ft., 24 (2 MVZ).

OREGON: _Baker Co._: East Pine Creek, 2-1/2 mi. NE Cornucopia, 6 (USBS);
McEwen, 2 (USBS); _Bourne_, 7 (USBS). _Clackamas County_: _Marks Creek,
12 mi. N of Howard_, 2 (USBS); Howard, 2 (USBS). _Crook County_: _Ochoco
R. S., 4000 ft._, 4 (MVZ). _Grant Co._: _Austin_, 2 (USBS); _Cold
Spring, 4900 ft., 8 mi. E Austin_, 4 (MVZ); Beech Creek, 1 (USBS);
_Strawberry Mts._, 6 (USBS); _north fork Malheur River, 21 mi. SE
Prairie City, 5000 ft._, 21 (MVZ). _Harney Co._: 10 mi. N. Harney, 1
(USBS); _Steen Mts., Keiger Gorge, 6900 ft._, 6 (USBS); Diamond, 4300
ft., 2 (USBS). _Jefferson Co._: Foley Creek, 12 mi. E Hay Creek, 1
(USBS). _Klamath Co._: Fort Klamath, 1 (USBS). _Lake Co._: Silver Creek,
7000 ft., Yamsey Mts., 1 (USBS); _2 mi. E Lakeview, 5200 ft._, 3 (MVZ).
_Malheur Co._: Jordan Valley, 4200 ft., 1 (USBS). _Umatilla Co._:
Meacham, 1 (USBS). _Union County_: Elgin, 2 (USBS). _Wallowa Co._:
Paradise, 10 mi. N Horse Creek, 7000 ft., 1 (USBS); _Minam Lake_, 1
(USBS); _16 mi. S and 3 mi. E Lostine, 5500 ft._, 9 (MVZ); _west fork
Wallowa River, 5000 ft., 2-1/2 mi. above Wallowa Lake_, 1 (FM); _near
Wallowa Lake, 4500 ft._, 3 (FM). _Wheeler County_: 11 mi. W and 7 mi. S
Mitchell, 4850 ft., 20 (MVZ).

WASHINGTON: _Asotin Co._: Anatone, 3300 ft., 1 (USBS). _Columbia
County_: Twin Buttes, 25 mi. SE Dayton, Blue Mts., 2 (MVZ); _Stayawhile
Spring, 5150 ft._, 4 (MVZ).

_Marginal records._--Washington: Anatone, 3300 ft. Oregon: East Pine
Creek, 2-1/2 mi. NE Cornucopia. Idaho: 1 mi. NE Heath, SW slope Cuddy
Mtn., 4000 ft.; Bald Mtn., R. S., Boise Nat'l Forest, 10 mi. S. Idaho
City, 7400 ft.; Trail Creek, Boise Nat'l Forest. Nevada: Harrison Pass
R. S., Ruby Mts.; Steel Creek, 7000 ft.; Wisconsin Creek, 7000 ft.; 13
mi. N Paradise Valley, 6700 ft. California: Lassen Creek; Buck Creek R.
S. Oregon: Fort Klamath; Howard; Meacham. Washington: Twin Buttes, 25
mi. SE Dayton, Blue Mts.


=Zapus princeps pacificus= Merriam

    _Zapus pacificus_ Merriam, Proc. Biol. Soc. Washington, 11:104,
        April 26, 1897; Preble, N. Amer. Fauna, 15:30, August 8, 1899.

    _Jaculus hudsonius_, Baird, Repts. Expl. and Surv. 111 8
        (pt. 1):433, July 14, 1858 (part--the part from Canoe Creek,
        California).

    _Zapus alleni_ Elliot, Field Columbian Mus., publ. 27, zool. ser.,
        1:212, April 19, 1898, type from Pyramid Peak, Lake Tahoe, El
        Dorado County, California.

    _Zapus trinotatus alleni_, Elliot, Field Columbian Mus. Publ. 91,
        zool. ser., 3:315, July 5, 1904; Preble, N. Amer. Fauna, 15:27,
        August 8, 1899.

    _Zapus pacificus alleni_, Howell, Univ. California Publ. Zool.,
        21:232, May 20, 1920.

    _Zapus trinotatus pacificus_, Bailey, N. Amer. Fauna, 55:233,
        August 29, 1936.

    _Zapus princeps alleni_, Hall, Mammals of Nevada; Univ. California
        Press, Berkeley, California, 579, July 1, 1946.

_Type._--Male, subadult, skin and skull, No. 80445, U. S. Nat. Mus.
Biol. Surv. Coll.; Prospect, Rogue River Valley, Jackson Co., Oregon;
obtained on August 29, 1896, by Edward A. Preble, original No. 1454.

_Range._--Sierra Nevada Mt's, from Kern Peak, Tulare County, California,
northeastward to Mt. Rose, Washoe County, Nevada, then northwestward
through the Trinity and Salmon mountains, California, to the upper Rogue
River Valley, Oregon, thence southwestward to South Yolla Bolly Mt'n,
Tehama County, California. See fig. 46. Zonal range: Transition,
Canadian, and Hudsonian.

_Description._--Size medium; color bright; back near Ochraceous-Buff
with admixture of black hair forming dark dorsal band; sides bright
Ochraceous-Buff with fine admixture of black hair; lateral line blending
with color of sides or wanting or indistinct; ventral surface white;
tail bicolored, grayish-brown above, yellowish-white below, in some
specimens with white tip; feet grayish-white above; ears dark, edged
with Ochraceous Buff; braincase relatively narrow; incisive foramina
relatively short; pterygoid fossae usually broad; proximal part of
inferior ramus of zygomatic process of maxillary broad; postpalatal
notch usually broadly rounded; auditory bullae relatively small and
flattened; nasals parallel sided; maxillary tooth-row short;
interorbital region moderately broad.

_Comparison._--From _Zapus princeps oregonus_, _Z. p. pacificus_ differs
in being brighter in all pigmented areas; more ochraceous and less
yellow laterally; dorsally more ochraceous and less black; size
averaging smaller; maxillary tooth-rows shorter; auditory bullae less
inflated and smaller; interorbital region averaging narrower; palatal
bridge averaging shorter; incisive foramina shorter and posteriorly
narrower; nasals parallel rather than narrowed posteriorly.

_Remarks._--Original describers considered both _Z. pacificus_ and _Z.
alleni_ as specifically distinct from _Z. trinotatus_. Merriam
(1897a:104) named _Z. pacificus_ and gave the following diagnostic
characters: short rostrum and nasals; small auditory bullae;
basioccipital broad between bullae. Elliot (1898:212) named _Z. alleni_
and ascribed to it the following diagnostic characters: cranium long and
narrow; nasals same breadth for entire length; palate wide; pterygoid
fossae wide posteriorly; auditory bullae small; basisphenoid and
basioccipital wide; upper tooth-rows short. Preble (1899:27) considered
_Z. alleni_ to be a subspecies of the species _Z. trinotatus_, remarking
that the skulls are similar to those of _Z. trinotatus_ but smaller with
much smaller bullae; in coloration the animals are lighter above and
without fulvous below. Preble remarked that the skull of _Z. alleni_
differs so greatly from that of _Z. montanus_ that comparison was not
required. Preble (_op. cit._:30) treated _Z. pacificus_ as a full
species. Howell (1920:233) considered _Z. pacificus_ and _Z. alleni_ to
be subspecies of _Z. pacificus_. Howell (_loc. cit._) pointed out size,
cranial, and color similarities between the two, and remarked that
_pacificus_ is clearly distinct from _Z. montanus_, its nearest
geographic neighbor. Hall (1946:578) arranged _Z. alleni_ as a
subspecies of _Z. princeps_, although not on grounds wholly satisfactory
to him because actual intergrades between _alleni_ and neighboring races
of _princeps_ were not available.

I here consider _Z. alleni_ to be synonymous with _Z. pacificus_; the
latter is a subspecies of _Z. princeps_. Certain diagnostic characters,
such as the shape and size of the os penis, the diameter and pigment
pattern of the hair, the over-all proportions of the skull, and the size
and shape of the teeth indicate that _alleni_ and _princeps_ belong to
the same species, even though animals from intermediate geographic areas
are not available to show actual intergradation.

The diagnostic characters referred to in the original description of _Z.
alleni_, as given earlier in this account, agree with characters of
specimens of _Z. p. pacificus_. Howell (1920:233) remarks that, in
coloration and length of foot, typical _alleni_ differs but slightly
from _pacificus_. Howell (_loc. cit._) noted, as I also have, that there
are slight cranial differences in specimens from various parts of the
range of _Z. p. pacificus_; these variations are somewhat clinal in
nature, cranial dimensions showing a slight increase from south to
north. The largest animals occur in western Tehama, Trinity, and
Siskiyou counties, California. Samples from various localities in
Jackson County, Oregon, are slightly smaller than these, but are larger
than specimens from the southern Sierra Nevada.

_Specimens examined._--Total, 264, distributed as follows:

CALIFORNIA: _Alpine County_: _Carson River, 1/4 mi. SW Woodfords, 5700
ft._, 3 (MVZ); _Diamond Valley, 5500 ft., 1 mi. SE Woodfords_, 6 (MVZ);
_Faith Valley_, 1 (MVZ). _El Dorado County_: _Glen Alpine Creek, near
Fallen Leaf Lake, 6600 ft._, 8 (MVZ); _1 mi. W Fyffe_, 1 (MVZ); _Fresno
County_: _Hume_, 1 (MVZ). _Mariposa County_: _Chinquapin, 6700 ft.,
Yosemite Nat'l Park_, 12 (MVZ); _E fork Indian Canyon, 7300 ft._, 8
(MVZ); _Merced Grove, Big Trees_, 7 (MVZ); _1 mi. E Merced Lake_, 5
(MVZ); _near Mono Meadow, Yosemite Nat'l Park_, 4 (MVZ); _near Mt.
Hoffman, 8100 ft., Yosemite Nat'l Park_, 5 (MVZ); _Porcupine Flat, 8100
ft., Yosemite Nat'l Park_, 9 (MVZ); _Yosemite Creek, Yosemite Valley_, 7
(MVZ); foot Yosemite Falls, Yosemite Nat'l Park, 8 (MVZ). _Mono County_:
_Walker Lake, 8000 ft._, 5 (MVZ); _Swager Canyon, 7800 ft._, 3; Mono
Lake P. O. 6500 ft., 4 (MVZ). _Placer Co._: Truckee River, Squaw Creek,
1 (SDM); _W bank Truckee River_, 1 (MVZ). _Plumas County_: Rich Gulch,
3850 ft., 11 mi. W and 8 mi. N Quincy, 2 (MVZ). _Shasta County_: Warner
Creek, 8000 ft., Lassen Peak, 6 (MVZ). _Siskiyou Co._: _Donomore Meadow,
5800 ft., 15 mi. W Hilt_, 7 (MVZ); Poker Flat, 5000 ft., 12 mi. NW Happy
Camp, 7 (MVZ); Little Shasta, 1 (USBS); Siskiyou Mts., 6000 ft., 2
(USBS); _Sisson_, 1 (SDM); _Mt. Shasta, 6500 ft._, 6 (MVZ). _Salmon
River Divide_, 2 (MVZ); _S fork Salmon River, 5000 ft._, 7 (MVZ).
_Tehama County_: _2 mi. W Black Butte, on Lassen Rd., 6800 ft._, 5
(MVZ); _2 mi. E Mineral, 5200 ft._, 2 (MVZ); 2 mi. S Yolla Bolly Mtn.,
11 (MVZ). _Trinity Co._: _N fork Coffee Creek, 4500 ft._, 34 (MVZ);
Canyon Creek, 4 (USBS); 8 mi. NE Hyampon, 2900 ft., 1 (MVZ); _3 mi. NNW
Mad River Bridge, 2900 ft., South Fork Mtn._, 5 (MVZ); _1-1/2 mi. N Mad
River Bridge, 3000 ft., South Fork Mtn._, 6 (MVZ); _1 mi. SW North Yolla
Bolly Mtn._, 14 (11 MVZ); _1/2 mi. S South Yolla Bolly Mtn._, 3 (MVZ).
_Tulare County_: _Jordan Hot Springs, Sierra Nevada Mts., 6700 ft._, 9
(MVZ); _Sherman Creek, Sequoia Nat'l Park_, 1 (MVZ); _Tokopah Valley,
7000 ft., Sequoia Nat'l Park_, 1 (MVZ); 2 mi. E Kern Peak, 9300 ft.,
Sierra Nevada Mts., 1 (MVZ). _Tuolumne County_: _head Lyle Canyon,
Yosemite Nat'l Park, 10,000 ft._, 9 (MVZ); _Tuolumne Meadows, 8600 ft.,
Yosemite Nat'l Park_, 1 (MVZ).

NEVADA: _Douglas County_: 1/2 mi. E Zephyr Cove, Lake Tahoe, 6400 ft., 1
(MVZ). _Ormsby County_: _S end Marlette Lake, 8000 ft._, 2 (MVZ); _1/2
mi. S Marlette Lake, 8150 ft._, 3 (MVZ). _Washoe County_: _1/2 mi. S Mt
Rose, 9500 ft._, 3 (2 MVZ); 3 mi. S Mt. Rose, 8500 ft., 3 (MVZ).

OREGON: _Jackson Co._: Prospect, 3 (2 USBS, 1 MVZ); _W slope Grizzly
Peak, 4600 ft._, 1 (USBS); _Siskiyou_, 1 (USBS); Longs Camp, N base
Ashland Peak, 3300 ft., 1 (USBS).

_Marginal records._--Oregon: Prospect. Nevada: 3 mi. S Mt. Rose, 8500
ft.; 1/2 mi. E Zephyr Cove, Lake Tahoe, 6400 ft. California: Mono Lake
P. O., 6500 ft.; 2 mi. E Kern Peak, 9300 ft., Sierra Nevada Mts.; Rich
Gulch, 3850 ft., 11 mi. W and 8 mi. N Quincy; Warner Creek, 8000 ft.,
Lassen Peak; 2 mi. S Yolla Bolly Mtn.; 8 mi. NE Hyampon, 2900 ft.;
Siskiyou Mts., 6000 ft.; Poker Flat, 5000 ft., 12 mi. NW Happy Camp.


=Zapus princeps princeps= J. A. Allen

    _Zapus princeps_ J. A. Allen, Bull. Amer. Mus. Nat. Hist., 5:71-72,
        April 28, 1893; Preble, N. Amer. Fauna, 15:23, August 8, 1899.

    _Type._--Female, adult, skin and skull; No. 5260/4140, Amer. Mus.
        Nat. Hist.; Florida, La Plata County, Colorado; obtained on June
        27, 1892, by Charles P. Rowley.

_Range._--Sierra Madre, Medicine Bow, Laramie, and Big Horn mountains of
Wyoming southward through Colorado into the Taos and San Juan mountains
in northern New Mexico. See fig. 46. Zonal range: Transition, Canadian
and Hudsonian.

_Description._--Size, medium; back dark usually with broad mid-dorsal
band of black mixed with Warm Buff or Ochraceous-Buff; sides light (Warm
Buff) but varying to Ochraceous-Buff, always with admixture of black
hair; lateral line distinct and broad, varying from Light
Ochraceous-Buff to Ochraceous-Buff; ventral surface white to base of
hairs, frequently suffused with Ochraceous-Buff; tail indistinctly
bicolored, tan to grayish-white below and pale brown above; hind feet
grayish-white above; ears edged with white or yellowish-white; skull
medium; large medial projection on inferior ramus of zygomatic process
of maxillary; palate moderately long; postpalatal notch usually broadly
rounded and posterior to posterior part of last molar; proximal part of
inferior ramus of zygomatic process of maxillary broad; pterygoid fossae
broad; auditory bullae moderately inflated.

_Comparisons._--From _Zapus princeps luteus_, _Z. p. princeps_ differs
as follows: Total length, tail and hind foot longer; color darker, being
less ochraceous; ears darker, edged with white or yellowish-white
instead of Ochraceous-Buff; lateral line more distinct; skull larger,
except least interorbital breadth which is smaller; auditory bullae
larger, more inflated; pterygoid fossae larger; incisive foramina
broader, longer, and posteriorly more truncate; nasals broader, tapering
less distally.

From _Zapus princeps idahoensis_, _Z. p. princeps_ differs in: Size
larger; darker with more Ochraceous-Buff; lateral line much more
distinct; underparts frequently suffused with Ochraceous-Buff rather
than seldom so; skull larger as regards length of palatal bridge, length
of zygomatic arch, and width of proximal part of inferior ramus of
zygomatic process of maxillary; pterygoid fossae broader; medial
projection on inferior ramus of zygomatic process of maxillary large
instead of reduced or absent; postpalatal notch usually anterior to, or
on a plane with, posterior face of last molars rather than posterior to
same.

_Remarks._--This subspecies retains most of its diagnostic characters in
all parts of its geographic range. An individual from the type locality,
Florida, Colorado, resembles _Zapus princeps luteus_ in color, but
cranially is most nearly like _Z. p. princeps_. A specimen from Tierra
Amarilla, New Mexico, a locality 25 miles north of, and in homogeneous
habitat with, El Rito, New Mexico, from which specimens of _Z. p.
luteus_ are known, shows resemblance to the latter in some cranial
characters (see account of _Zapus princeps luteus_) but is most nearly
like _Z. p. princeps_ to which it is referred.

Animals from Medicine Wheel Ranch, 9000 ft., 28 mi. E Lovell, Wyoming,
which are here referred to _Z. p. princeps_, show intergradation with
_Zapus princeps idahoensis_, being similar in size of pterygoid fossae,
breadth of postpalatal notch, and in size and degree of inflation of the
auditory bullae, but differ in color and in other cranial characters.
Specimens from 2 mi. E Shriver, 6500 ft., Montana, which lack the
distinct lateral line and ventral suffusion of Ochraceous-Buff, are here
referred to _Z. p. idahoensis_.

_Specimens examined._--Total, 344, distributed as follows:

COLORADO: _Archuleta County_: _upper Navajo River_, 5 (CMNH); Navajo
River, 6 (CMNH). _Boulder Co._: _12-1/2 mi. S Estes Park_, 2; _3 mi. S
Ward_, 3; Gold Hill, 1 (USBS); _7 mi. NW Nederland's_, 2 (UM); _3 mi. E
Pine Cliff_, 3 (CMNH). _Chaffee County_: _1-1/2 mi. S Monarch, 10,500
ft._, 2 (OKLA). _Conejos Co._: Antonito, 1 (USBS); _5 mi. S and 24 mi. W
Antonito, 9600 ft._, 2. _Costilla Co._: _7 mi. SE Russell, 9200 ft._, 1
(MVZ); Fort Garland, 6 (USBS). _El Paso County_: Minnehaha, Half Way, 5
(UM). _Grand Co._: _Rocky Mtn. Nat'l Park_, 5 (UM). _Gunnison County_:
Gothic, 10 (8 OKLA; 2 USBS); _Major Creek, foot of Monarch Pass_, 1
(OKLA). _Jackson Co._: Arapahoe Pass, Rabbit Ear Mts., 1 (USBS). _La
Plata Co._: _7 mi. N Florida, Florida River, 7146 ft._, 8 (MVZ);
Florida, 6500 ft., 11 (1 FM; 9 AMNH). _Larimer Co._: Elkhorn, 7000 ft.,
1 (USBS); _19-1/2 mi. W and 2-1/2 mi. S Loveland, 7300 ft._, 3. _Mineral
Co._: _Wasson Ranch, Creede_, 1; _3 mi. E Creede_, 1; _23 mi. S and 11
mi. E Creede, 9300 ft._, 5. _Rio Blanco Co._: _9-1/2 mi. SW Pagoda Peak,
7700 ft._, 5; Meeker, 1 (USBS). _Rio Grande County_: _Rock Creek Camping
Area_, 1 (OKLA). _Saguache Co._: Saguache Park, Cochetopa Forest, 1
(USBS); _22 mi. W Saguache_, 1 (MVZ); _20 mi. S Saguache, Cochetopa
Pass_, 1 (USBS). _San Juan County_: 6-1/2 mi. SW Silverton, 4.

NEW MEXICO: _Rio Arriba Co._: Tierra Amarilla, 1 (USBS). _Taos Co._:
_Hondo Canyon, 8200 ft., west slope Taos Mts._, 1 (USBS); east slope
Taos Mts., 8800 ft., 1 (USBS).

WYOMING: _Albany County_: 32 mi. N and 12-1/2 mi. E Laramie, 6080 ft.,
1; _30 mi. N and 10 mi. E Laramie, 6760 ft._, 1; _29 mi. N and 8-3/4 mi.
E Laramie, 6420 ft._, 6; _2 mi. S Browns Peak, 10,600 ft._, 2; _3 mi.
ESE Browns Peak, 10,000 ft._, 8; _8 mi. E and 4 mi. S Laramie, 8600
ft._, 2; _8 mi. E and 6 mi. S Laramie, 8500 ft._, 1; _1 mi. ESE Pole
Mtn., 8350 ft._, 2; _1-1/2 mi. ESE Pole Mtn., 8200 ft._, 1; _2 mi. SE
Pole Mtn., 8300 ft._, 3; Centennial, 8120 ft., 1. _Big Horn County_:
Medicine Wheel Ranch, 9000 ft., 28 mi. E Lovell, 36; _12 mi. E and 2 mi.
N Shell, 7500 ft._, 13; _17 mi. E and 3 mi. S Shell, 9000 ft._, 1;
_17-1/2 mi. E and 4-1/2 mi. S Shell, 9100 ft._, 6. _Carbon County_:
Bridgers Pass, 18 mi. SW Rawlins, 7500 ft., 6; _Lake Marie, Medicine Bow
Nat'l Forest, 10,400 ft._, 6; _14 mi. E and 6 mi. S Saratoga_, 5; _10
mi. N and 10 mi. E Encampment, 8000 ft._, 1; _10 mi. N and 12 mi. E
Encampment, 7200 ft._, 2; _10 mi. N and 14 mi. E Encampment, 8000 ft._,
28; _9 mi. N and 3 mi. E Encampment_, 2; _8 mi. N and 8 mi. E
Encampment, 8900 ft._, 1; _8 mi. N and 14 mi. E Encampment, 8400 ft._,
5; _8 mi. N and 14-1/2 mi. E Encampment, 8100 ft._, 12; _8 mi. N and 16
mi. E Encampment, 8400 ft._, 6; _8 mi. N and 22 mi. E Encampment, 10,000
ft._, 1; _8 mi. N and 19-1/2 mi. E Savery, 8800 ft._, 12; _8 mi. N and
20 mi. E Savery, 8800 ft._, 1; _7-1/2 mi. N and 18 mi. E Savery, 8400
ft._, 2; _7-1/2 mi. N and 18-1/2 mi. E Savery, 8400 ft._, 1; _7 mi. N
and 18 mi. E Savery, 8400 ft._, 2; _6 mi. N and 13-1/2 mi. E Savery,
8400 ft._, 6; _6 mi. N and 14 mi. E Savery, 8350 ft._, 6; 4 mi. N and 8
mi. E Savery, 7300 ft., 1. _Converse County_: 21 mi. S and 24 mi. W
Douglas, 7400 ft., 6; _21 mi. S and 24-1/2 mi. W Douglas, 7400 ft._, 3;
_21-1/2 mi. S and 24-1/2 mi. W Douglas, 7600 ft._, 15; _22-1/2 mi. S and
24-1/2 mi. W Douglas, 7600 ft._, 1; _23 mi. S and 25 mi. W Douglas, 7800
ft._, 7. _Johnson County_: _6-1/2 mi. W and 2 mi. S Buffalo, 5700 ft._,
4; _5-1/2 mi. W and 1-1/2 mi. S Buffalo, 5520 ft._, 3; _5-1/2 mi. W and
1 mi. S Buffalo, 4800 ft._, 1; 1 mi. W and 4/5 mi. S Buffalo, 4800 ft.,
1. _Laramie County_: 5 mi. W and 1 mi. N Horse Creek P. O., 3. _Natrona
County_: _2 mi. W and 7 mi. S Casper, 6370 ft._, 2. _Washakie County_: 9
mi. E and 5 mi. N Tensleep, 7400 ft., 2; 9 mi. E and 4 mi. N Tensleep,
7000 ft., 5.

_Marginal records._--Wyoming: Medicine Wheel Ranch, 9000 ft., 28 mi. E
Lovell; 21 mi. S and 24 mi. W Douglas, 7400 ft.; 5 mi. W and 1 mi. N
Horse Creek P. O. Colorado: Gold Hill; Minnehaha. New Mexico: E slope
Taos Mts.; Tierra Amarilla. Colorado: Florida; 6-1/2 mi. SW Silverton;
Meeker. Wyoming: Bridgers Pass, 18 mi. W Rawlins, 7500 ft.


=Zapus princeps saltator= J. A. Allen

    _Zapus saltator_ J. A. Allen, Bull. Amer. Mus. Nat. Hist., 12:3-4,
        March 4, 1899; Preble, N. Amer. Fauna, 15:31, August 8, 1899.

    _Zapus princeps_, Preble, N. Amer. Fauna, 15:23, August 8, 1899
        (part--the part from Glacier, British Columbia).

    _Zapus hudsonius_, Kermode and Anderson, Rep. Prov. Mus. Nat. Hist.
        for 1913:21, 1914.

    _Zapus princeps saltator_, Hall, Univ. California Publ. Zool.,
        37:10, April 10, 1931.

_Type._--Female, subadult, skin and skull, No. 14408, Amer. Mus. Nat.
Hist.; Telegraph Creek, British Columbia; obtained on August 23, 1897,
by A. J. Stone.

_Range._--Southern Yukon and southeastern Alaska south in British
Columbia, to Bella Coola Inlet and Glacier. See fig. 46. Zonal range:
Canadian and Hudsonian.

_Description._--Size medium; back near Ochraceous-Buff, overlaid with
black hairs forming dark dorsal band thickly flecked with ochraceous;
sides lighter than back; lateral line usually distinct; belly pure
white, sometimes faintly suffused with Ochraceous-Buff; tail bicolored,
dark above and grayish-white below; hind feet grayish-white above; ears
dark, edged with yellowish-white or Ochraceous-Buff; incisive foramina
long, broad posteriorly; palatal bridge relatively short; postpalatal
notch anterior to posterior border of last molars; proximal part of
inferior ramus of zygomatic process of maxillary without enlarged median
projection; zygomatic arch short.

_Comparisons._--For comparison with _Zapus princeps kootenayensis_ and
_Zapus princeps idahoensis_ see accounts of those subspecies.

_Remarks._--The geographic range of _Z. p. saltator_, as here
understood, includes several localities heretofore considered to be
within the geographic ranges of neighboring subspecies. Specimens from
Indianpoint Lake, 15 mi. N of Barkerville, British Columbia, for
example, which Hall (1934:379) considered nearer _Z. p. princeps_, are
here referred to _Z. p. saltator_, with which they closely agree in
cranial measurements and color of pelage. One individual from Glacier,
British Columbia, thought to be _Z. p. princeps_ by Preble (1899:32), is
here considered to show intergradation between _Z. p. kootenayensis_ and
_Z. p. saltator_ but is more nearly like _Z. p. saltator_ to which it is
here referred. Intergradation between _Zapus princeps idahoensis_ and
_Z. p. saltator_ is noted, in color and in shape and size of the
incisive foramina, in a specimen from Vermilion Crossing, Kootenay,
British Columbia. The majority of cranial characters show these animals
to be referable to _Z. p. idahoensis_. Specimens from Mt. Revelstoke,
3400 ft., British Columbia, show intergradation in shape of auditory
bullae, in breadth of pterygoid fossae, and in shape and size of
antorbital foramina between _Z. p. idahoensis_ and _Z. p. saltator_.
Resemblance in pelage and in the majority of cranial characters
indicates that these specimens are best referred to _Z. p. saltator_.

_Specimens examined._--Total, 187, distributed as follows:

ALASKA: Taku River, 1 (MVZ).

BRITISH COLUMBIA: Atlin, 7 (6 CAS; 1 PM); _Deep Creek, 60 mi. above
Telegraph Creek_, 1 (USBS); _Sawmill Lake, near Telegraph Creek_, 6
(MVZ); junction 4 mi. N Telegraph Creek, 1 (ROM); McDame Post, Dease
River, 1 (USBS); _Stikine River, at Glenora_, 28 (MVZ); _Kispiox
Valley, 23 mi. N Hazelton_, 3 (MVZ); _9-mi. Mtn., 4500 ft., NE
Hazelton_, 1 (MVZ); Hazelton, 959 ft., 20 (MVZ); Bear River, 7 mi. N
Bear Lake, 1 (USBS); Charlie Lake, Fort St. John, 1 (PM); _Moose River_,
2 (PM); Tupper Creek, 7 (PM); _Babine_, 2 (USBS); _Port Simpson_, 3
(USBS); 12 mi. N Summit Lake, Alaska Highway, 3300 ft., 3 (NMC);
_Giscome_, 1 (USBS); _Ootsa Lake_, 3 (PM); Inverness, mouth Skeena
River, 1 (USBS); W end Eutsuk Lake, 1 (PM); Wapiti, head of Middle
Branches River, 1 (USBS); Hagensborg, 15 (NMC); _Stuie, Cariboo Mtn.,
4700 ft._, 2 (NMC); Rainbow Mts., Mt. Brilliant, 5000 ft., 10 (NMC); N 7
Wistaria P. O., 13 (NMC); _Mt. McLean, Lillooet_, 1 (PM); Mt. Robson P.
O., Mt. Robson Park, 1 (MVZ); _Indianpoint Lake, 15 mi. NE Barkerville_,
42 (29 MVZ; 18 PM); Cottonwood P. O., 2 (MVZ); Mt. Revelstoke, 3400 ft.,
6 (PM); Glacier, 1 (ROM).

YUKON: Rose River, mile 95 on Canol Road, 1 (NMC).

_Marginal records._--Yukon: Rose River, mile 95 on Canol Road, British
Columbia; McDame Post, Dease River; Charlie Lake, Fort St. John; Tupper
Creek; Wapiti, head of Middle Branches River; Mt. Robson P. O., Mt.
Robson Park; Mt. Revelstoke, 3400 ft.; Cottonwood P. O.; Rainbow Mts.,
Mt. Brilliant, 5000 ft.; Inverness, mouth Skeena River. Alaska: Taku
River. British Columbia: Atlin.


=Zapus princeps utahensis= Hall

    _Zapus princeps utahensis_ Hall, Occ. papers, Mus. Zool., Univ.
        Michigan, 296:3, November 2, 1934.

    _Jaculus Hudsonius_, J. A. Allen, Bull. Essex Inst., 6:65, April,
        1874 (part--the part concerning Great Salt Lake Valley, Utah).

    _Zapus princeps princeps_, Wolfe, Jour. Mamm., 91:154, May 9, 1928.

    _Zapus princeps idahoensis_, Davis, Recent Mammals of Idaho, Caxton
        Printers, Caldwell, Idaho, p. 341, April 5, 1939 (part--the part
        from southeast Idaho).

_Type._--Female, adult, skin and skull; No. 59153, Museum of Zoology,
University of Michigan; Beaver Creek, 19 mi. S Manila, Daggett County,
Utah; obtained on July 16, 1928, by A. and R. D. Svihla, original No.
176.

_Range._--Southeastern Idaho and extreme western Wyoming (Teton, Snake,
and Uinta Mt's) southward through Uinta, Wasatch, Oquirrh, and Beaver
Mt's of Utah. See fig. 46. Zonal range: Transition, Canadian, and
Hudsonian.

_Description._--Size, large; back from Cinnamon-Buff to Warm Buff
overlaid with black hairs; sides lighter with less admixture of black
hairs; lateral line indistinct, sometimes wanting; tail bicolored,
brownish-black above, white to yellowish-white beneath; feet
grayish-white above; ventral surface white to base of hairs; ears dark,
edged with white to yellowish-white; skull large; palatal bridge
relatively short; upper tooth-rows diverging anteriorly; occipitonasal
length great; interorbital region broad; zygomata widely bowed;
postpalatal notch anterior to posterior face of last molars; mastoid
width great.

_Comparisons._--From _Zapus princeps princeps_, _Z. p. utahensis_
differs in: color dorsally and laterally less ochraceous, lacking broad
lateral line; skull larger in every part measured, excepting length of
palatal bridge and breadth of palate at M3; zygomata more bowed; upper
tooth-rows more divergent anteriorly; postpalatal notch anterior to
posterior border of last molars.

Compared with _Zapus princeps cinereus_, _Z. p. utahensis_ differs as
follows: Size averaging larger; upper parts darker, Cinnamon-Buff not
Pinkish-Buff; incisive foramina wider posteriorly; palate wider;
zygomata more robust.

For comparison with _Zapus princeps idahoensis_ see account of that
subspecies.

_Remarks._--_Zapus princeps utahensis_ most closely resembles the
several subspecies in the Great Basin in its large size, widely bowed
zygomata, and posteriorly broadened incisive foramina. Intergradation
between _Z. p. utahensis_ and _Zapus princeps cinereus_, geographically
the nearest of the Great Basin subspecies, is not known. Intergradation
in color and cranial characters occurs between _Zapus princeps
idahoensis_ and _Z. p. utahensis_ in specimens from 17 mi. E and 4 mi. N
of Ashton, Idaho. All these specimens are, however, referable to _Z. p.
idahoensis_. Animals from 9 mi. SE Irwin and from 3 mi. SW Victor,
Idaho, resemble _Z. p. utahensis_ in most differential characters
(dorsally ochraceous, lateral line more distinct, incisive foramina
large, palate broad anteriorly, auditory bullae less inflated), and are
here referred to _Z. p. utahensis_. A series of specimens from the head
of Crow Creek, Idaho, were considered by Davis (1939:340) to be
intergrades between _Z. p. idahoensis_ and _Z. p. utahensis_; he thought
that the specimens were more nearly like _Z. p. utahensis_ in color, but
cranially (80 per cent in average ratio of anterior width of palate to
posterior width of palate), more nearly like _Z. p. idahoensis_, to
which subspecies he referred them. I have examined these specimens and
find them to be more nearly like _Z. p. utahensis_ not only in color but
in cranial characters as well. For example, the average ratio obtained
by me for anterior width of palate to posterior width of palate is 72
per cent, rather than 80 per cent as given by Davis (_loc. cit._). Other
cranial characters, size of the incisive foramina, shape of the foramen
magnum, and shape of the auditory bullae, indicate relationship with _Z.
p. utahensis_ to which they are here referred. Two immature individuals
from Strawberry Creek, 20 mi. E Preston, Idaho, considered to be _Z. p.
idahoensis_ by Davis (_op. cit._:341), also are here referred to _Z. p.
utahensis_.

_Specimens examined._--Total, 178, distributed as follows:

IDAHO: _Bonnerville County_: _9 mi. SE Irwin, 6400 ft._, 3. _Caribou
Co._: Head Crow Creek, Preuss Mts., 7500 ft., 6 (USBS). _Franklin
County_: Strawberry Creek, 20 mi. NE Preston, 6700 ft., 2 (MVZ). _Teton
County_: 3 mi. SE Victor, 6 (MVZ).

UTAH: _Beaver County_: Puffer Lake, 1 (UU). _Daggett County_: junction
Deep Creek and Carter Creek, 7900 ft., 2 (UU). _Duchesne Co._: _Currant
Creek, Uinta Forest_, 2 (USBS). _Morgan Co._: _exact locality not
given_, 1 (UU). _Rich County_: 12 mi. SW Woodruff, 1 (MVZ). _Salt Lake
County_: _Lambs Canyon, 2 mi. above Parleys Canyon, 7000 ft._, 1 (UU);
_head Lambs Canyon, 9000 ft._, 3 (UU); _Salamander Lake and Lambs
Canyon, 9000 ft._, 11 (UU); _"The Firs," Mill Creek Canyon_, 2 (UU);
_Brighton, Silver Lake P. O., 8700 ft., Cottonwood Canyon_, 1 (UU);
_Brighton, Big Cottonwood Canyon, 8000 ft._, 1 (UU); _1 mi. above Alta_,
4 (UU); Butterfield Canyon, approximately 5 mi. above Butterfield
Tunnel, 3 (UU). _Sanpete Co._: _8 mi. E Fairview and 5 mi. S Mammoth R.
S., Manti Nat'l Forest, 9000 ft._, 1 (USBS); _Baldy R. S., Manti Nat'l
Forest_, 1 (UU); Ephraim, 8850 ft., 1 (USBS). _Summit County_: _Henrys
Fork, Uinta Mts., 8000 ft._, 4 (UU); 14 mi. S and 2 mi. E Robertson,
9300 ft., 3. _Uintah County_: 21 mi. W and 15 mi. N Vernal, 10,050 ft.,
1. _Utah County_: Payson Lake, 8300 ft., 12 mi. SE Payson, Mt. Nebo, 12
(UU); _1 mi. E Payson Lake, 8300 ft., Mt. Nebo_, 3 (UU). _Wasatch
County_: Provo River, 3 mi. N Soapstone R. S., Wasatch Nat'l Forest, 1
(UU).

WYOMING: _Lincoln County_: 3 mi. N and 11 mi. E Alpine, 5650 ft., 37.
_Teton County_: 1/4 mi. E Moran, 6700 ft., 4; _Bar B. G. Ranch, 6500
ft., 2-1/2 mi. NE Moose_, 11; _Moose, 6225 ft._, 1. _Uinta County_: 2
mi. E Robertson, 7200 ft., 1; _9 mi. S Robertson, 8000 ft._, 21; _9 mi.
S and 2-1/2 mi. E Robertson, 8000 ft._, 1; _9-1/2 mi. S and 1 mi. W
Robertson, 8600 ft._, 2; _10 mi. S and 1 mi. W Robertson, 8700 ft._, 18;
_10-1/2 mi. S and 2 mi. E Robertson, 8900 ft._, 1; _13 mi. S and 1 mi. E
Robertson, 9000 ft._, 4; _5 mi. E Lonetree_, 1 (ROM).

_Marginal records._--Wyoming: 1/4 mi. E Moran, 6700 ft.; 2 mi. E
Robertson, 7200 ft. Utah: junction Deep Creek and Carter Creek, 7900
ft.; Paradise Park, 21 mi. W and 15 mi. N Vernal, 10,500 ft.; Ephraim,
8500 ft.; Puffer Lake; Payson Lake, 8300 ft., 12 mi. SE Payson, Mt.
Nebo; Butterfield Canyon, approximately 5 mi. above Butterfield Tunnel.
Idaho: Strawberry Creek, 20 mi. NE Preston, 6700 ft.; 3 mi. SW Victor.


=Zapus hudsonius= (Zimmerman)

(Synonymy under subspecies)

_Range._--From Pacific Coast of Alaska eastward to Atlantic Coast; from
northern limit of tree-growth south into central Colorado and
northeastern parts of Oklahoma and Georgia. See fig. 47.

    [Illustration: FIG. 47. Distribution of _Zapus hudsonius_.

     Guide to subspecies

     1. _Z. h. acadicus_      6. _Z. h. hudsonius_
     2. _Z. h. alascensis_    7. _Z. h. intermedius_
     3. _Z. h. americanus_    8. _Z. h. ladas_
     4. _Z. h. campestris_    9. _Z. h. pallidus_
     5. _Z. h. canadensis_   10. _Z. h. preblei_
     6. _Z. h. hudsonius_    11. _Z. h. tenellus_]

_Externals._--Size small to medium (total length 188 mm to 216 mm); tail
longer than head and body (112 mm to 134 mm) and bicolored, pale brown
to brownish-black above, white to yellowish-white below; hind feet long
(28 mm to 31 mm), grayish-white above; back ochraceous to dark brown;
sides paler than back with dark hair interspersed; lateral line usually
present but sometimes indistinct or entirely absent (when present
usually clear Ochraceous-Buff); ventral coloration white, sometimes with
suffusion of ochraceous; guard hairs average 115 microns (96u to 140u)
in diameter; underhair with pigment pattern in form of hollow, narrow
rectangles; cuticular scales of underhair large and fewer than those of
the underfur of _Z. trinotatus_, but underhair of _Z. hudsonius_
otherwise resembles that of _Z. trinotatus_.

_Baculum._--Size small (total length 4.5 mm to 4.9 mm); base medium in
width (0.64 mm to 0.72 mm); tip narrow (0.24 mm to 0.26 mm) and dished
out in dorsal aspect, blunted; shaft rounded, curving gently upward at
tip.

_Skull._--Small to medium and relatively narrow in relation to length;
rostrum pointed and short; mastoid region relatively narrow; incisive
foramina short; base of zygomatic process of squamosal narrow; coronoid
process of mandible short, relatively weak. Upper premolar usually small
(averaging .30 mm in length and .35 mm in breadth) sometimes functional
(most often so in old adults), occlusal surface divided by single
shallow re-entrant fold, which in worn teeth forms centrally located
lake; tooth-row short as compared to that of other species; individual
cheek-teeth usually smaller than those of other species; lower
cheek-teeth shorter and narrower than those of other species; angle of
mandible strongly inflected.


GEOGRAPHIC VARIATION

The species _Z. hudsonius_ is divisible into 11 subspecies based on
differences in color, relative proportions of the tail, hind feet, body,
and size and shape of parts of the skull (zygomata, braincase, incisive
foramina, auditory bullae, pterygoid fossae, rostrum, and interorbital
breadth).

Color of the pelage varies, as a general rule, from dark-backed,
dull-sided individuals in the northern parts of the geographic range of
the species to light-backed, bright-sided individuals in the southern
parts of the range.

Individuals from the southernmost geographic races (_Z. h. americanus_
and _Z. h. pallidus_) are the smallest for the species and those from
the northernmost subspecies (_Z. h. alascensis_) are the largest. One
subspecies, _Z. h. campestris_, from the central part of the range of
the species, however, seems to be out of the cline. This form inhabits
the eastern foothills of the Rocky Mountains and is a robust animal
approaching _Z. princeps_ in size.

Seemingly there is no clinal variation in the several qualitative
features of the cranium, for instance in the shape of the auditory
bullae, shape of the incisive foramina, and shape of the postpalatal
notch. On the other hand, the dimensions of the entire skull show that
the larger crania are of the northernmost subspecies and the smaller of
the southernmost subspecies.

NATURAL HISTORY

_Habitat._--_Zapus hudsonius_ occurs in low undergrowth usually of
grasses or forbs or both, in open coniferous forests, deciduous hardwood
groves, or in stands of tall shrubs and low trees, but most frequently
in open, moist areas.

Quimby (1951:75) notes that jumping mice were more common in the moist
lowlands than in the drier uplands. More were in the open type lowlands
than in the forested type, and these mice favored habitats normally
bordered by small streams affording moist to semi-aquatic living
conditions. The reports of Goodwin (1924:255), Christian (1936:416), G.
S. Miller (1899:329), Cory (1912:249), Lyon (1936:277), Stoner
(1918:123), and others, although concerning widely different parts of
North America, indicate that _Z. hudsonius_ selects habitats in
vegetation of like form, even though different assemblages of plant
species may be involved.

An average of 11.91 mice per acre was recorded by Quimby (1951:91) from
a study plot at Itasca Park, Clearwater County, Minnesota. He gives the
monthly population densities per acre for _Z. hudsonius_ at Centerville,
Anoka County, Minnesota, as follows: June 2.78, July 3.57, August 3.10,
and September 1.81. Blair's (1940:248) data on bi-monthly population
density per acre for _Z. hudsonius_ on the Edwin S. George Reserve,
Livingston County, Michigan, are remarkably similar, when adjusted on a
monthly basis, to those obtained by Quimby (_loc. cit._). Blair's (_loc.
cit._) monthly population densities per acre are as follows: June 3.90,
July 3.85, August 3.10, and September 2.00. Townsend (1935:90) estimated
population densities per acre for _Z. hudsonius_ in central New York
state, at 11 to 72 individuals. As Quimby (1951:92) points out,
Townsend's figures are probably too high, as commonly is the case when
the moving quadrat technique is used because animals from neighboring
areas enter the trapped area to take over the niches made available by
their predecessors' removal.

The population of _Z. hudsonius_ may vary considerably from year to year
as well as seasonally. Blair (1940:249) found notably fewer jumping mice
on the George Reserve in 1938 than in 1939. Quimby (1951:94) found the
numbers of _Zapus_ to be highly variable and thought that there was a
rapid turnover. Young animals were not caught until July when 25 per
cent were either juveniles, young, or subadults; from this time on these
age classes increased to a high of sixty-one per cent in September.
Quimby (_loc. cit._) found that separating the individuals into their
proper age classes was more difficult in September, since the young
from early litters are adultlike in appearance. His data indicate as he
remarked, "That the over-wintering adults are, for the most part,
gradually replaced by the young of the year as the summer progresses."

The sexes in _Z. hudsonius_ vary only slightly from a one to one ratio.
Quimby (1951:63) found a sex ratio of 110 females to 100 males and Blair
(1940:245) records a sex ratio of 113 males to 100 females. Townsend
(1935:42) records a sex ratio in central New York of 155 males to 100
females. Such a wide variation from a one to one ratio suggest that the
moving quadrat technique, which Townsend (1935:90) employed in obtaining
his data, may be, in some way unknown to me, more selective for the
males.

_Behavior._--The saltatorial powers of _Z. hudsonius_ are well developed
and often have been described in the literature. Stoner (1918:123)
remarks that, "When disturbed _hudsonius_ moves away by a series of
leaps ... the distance traversed in one of these leaps is from six to
eight feet."; Cory (1912:249) observed these mice to make surprisingly
long leaps, and, according to him, a distance of 10 feet is by no means
unusual; Handley and Patton (1947:49) credit these animals with jumping
eight to ten feet at a single bound; Hamilton (1935:190) remarked that
he noted an average of not more than four to six feet per jump; Townsend
(1935:91) observed one individual make jumps of about two feet; and
Harper (1932:29) records a jumping mouse leaping for distances of two to
three feet. Quimby (1951:72) notes that he had never seen one jump
farther than three feet. He found that the greatest jumps occurred
initially and normally covered a distance of two to three feet;
subsequent leaps were shorter but more rapid. A jumping mouse in full
retreat progressed by jumps of about one foot.

Statements concerning the gait of _Z. hudsonius_ are not in agreement
but the consensus of opinion is that these animals when unfrightened
progress by a series of hops of one to six inches, or, occasionally,
with a slow creeping motion while the animal is on all fours. When
frightened, however, their progress is by long bounds; the mice make a
series of two or three such leaps to the nearest protective cover, and
then sit motionless until pursued.

Concerning the use of the tail as a balancing organ, G. S. Miller
(1899:330) describes the behavior of a jumping mouse from which the tail
had been severed by the sickle of a mowing machine. "When I approached,
it made violent efforts to escape, but the moment it was launched in the
air, its body, deprived of its balancing power, turned end over end so
that it was as likely as not to strike the ground facing the direction
from which it had come."

Riparian animals such as _Z. hudsonius_ need enter the water to escape
from enemies or perhaps in search of food. _Zapus hudsonius_ can and
does swim. Hamilton (1935:190) found it to be a strong swimmer capable
of remaining in the water for from four to five minutes. According to
Hamilton (_loc. cit._), when the mouse is swimming the head is held
high, the tail is arched near its middle, and only the hind limbs are
employed in propulsion. According to Sheldon (1938:327), Philip Allan,
in northern Minnesota, saw many _Z. hudsonius_ swimming three or four
inches under the surface of the water. The mice swam upstream and only
the hind legs were employed in the swimming movements. N. A. Preble
(1944:200), at Archer's Pond, 3 miles southeast of Center, Ossipee
County, New Hampshire, observed a jumping mouse swimming rapidly under
water toward another portion of the shore 30 or 40 feet away. The mouse,
swimming less than a foot beneath the surface, was vigorously using both
forefeet and hind feet, but the long tail trailing limply behind,
contributed in no way to the animal's movements. Quimby (1951:72)
released five of the mice, one at a time, in the open water of a lake.
He followed alongside in a boat and observed that, "In all instances the
animals proved to be excellent swimmers both on and underneath the
surface. The methods of progression were similar to land movements; i.
e., the limbs were employed differently at various times depending upon
the speed. When first placed in water they moved rapidly by lunges
produced by sweeping strokes of the hind limbs employed simultaneously.
This movement was accomplished similarly to the long jumps made on
land ... Following the first excited lunges, they settled down to a
steadier and slower gait using all four limbs one at a time. The
anterior part of the body was held high in the water ... When approached
too closely, they attempted to escape by diving. The maximum distance
noted was about four feet ... One was able to swim vigorously for
approximately three minutes after which it tired greatly and was in
danger of drowning."

As concerns digging ability, Goodwin (1935:148) reports that _Z.
hudsonius_ makes its own burrows; these are short and close to the
surface in the summer but longer, deeper, and below the frost-line in
winter. Two captives used their forefeet and nails in digging a tunnel
in the foot of soil that Goodwin (_loc. cit._) had placed in their cage.
Quimby (1951:72) remarks that captives excavate soil by means of the
front feet and throw the soil out behind; as the burrow deepened the
hind feet were also utilized to throw the loose soil out of the burrow.

_Zapus hudsonius_ climbs; Sheldon (1934:293) observed captive animals to
climb over small evergreen trees in their cages. They moved with
surprising sureness and agility, chasing each other among the branches
or sitting for several minutes at a time on one of the limbs. Hamilton
(1935:190) found that the mice ran over limbs and brush which were
placed in their outdoor enclosure.

Ordinarily _Z. hudsonius_ is nocturnal, appearing in the early dusk and
remaining active until pre-dawn. Occasional individuals are abroad in
daylight hours. Sheldon (1934:293) found in Nova Scotia that _Z.
hudsonius_ is most active from early dusk through the night, but that it
may be abroad in daylight as well. Her statements are based on trapping
results, field observations, and observations made on captive
individuals. Quimby (1951:73) found that _Z. hudsonius_ in Michigan is
mostly nocturnal; however, he saw mice on a few occasions in the
daytime. Diurnal activity seems to be increased in cloudy or damp
weather; Quimby (_loc. cit._) almost invariably trapped more of these
mice on cloudy, damp days than on other days.

This jumping mouse usually is silent but does utter various sounds.
Sheldon (1934:295) records squeaking and clucking noises. Quimby
(1951:73) records the clucking noise described by Sheldon (_loc. cit._)
and mentions also the squeaking and suckling sounds produced by the
small young. This mouse is most vociferous when young or when about to
go into hibernation. Sheldon (1938:327) writes that _Z. hudsonius_ makes
a drumming noise by vibrating the tail against dry leaves.

Many data are available concerning the hibernation of _Z. hudsonius_. In
general it seems necessary for the mice to put on a certain amount of
fat preparatory to hibernation. This fat is deposited in a thin layer
over the inside of the skin, over the back, and in the body cavities.
The thickest deposits are in and about the inguinal region.

Quimby (1951:83) noted that gain in weight was accelerated in a brief
period prior to entrance into hibernation. This relationship of rapid
gain in weight to hibernation allows a person to estimate the date of
hibernation. Cold weather seems to hasten hibernation, but less so than
the correct physiologic condition which is foreshadowed by a rapid gain
in weight. For example, Quimby's (1951:84) data reveal that mice that
were moved to a heated room gained weight and hibernated in a fashion
similar to those in unheated surroundings. Hamilton (1935:193) states
that, "It seems necessary for the mouse to lay on a certain amount of
fat before it is capable of hibernation." Hamilton (_loc. cit._)
reported that 18 specimens of _Z. hudsonius_ taken [presumably in an
active state] near Ithaca, New York, on November 13, were without a
trace of fat.

Data that are available concerning the hibernation sites of _Z.
hudsonius_ show that almost invariably these mice seek shelter in
burrows beneath the surface of the ground and there construct nests of
grass, leaves, or some other vegetation. Nicholson (1937:103) found a
hibernating _Z. hudsonius_ on the George Reserve, Livingston County,
Michigan, on October 20. The mouse was in a nest, composed of 10 to 12
damp elm leaves, in a sand bank two feet three inches vertically and
three feet nine inches horizontally from the surface. On April 11, 1948,
Schwartz (1951:228) found five nests (three with occupants) of _Z.
hudsonius_ at Jefferson City, Cole County, Missouri. All nests were one
foot beneath the surface of a pile of coal-ash, which was about three
and one-half feet high and five feet in diameter. The nests were
spherical, approximately four inches in diameter and consisted of dried
oak leaves and bits of dried grass. Grizzell (1949:74) found two
hibernating jumping mice at the Patuxent Research Refuge, Laurel,
Maryland, in January, 1948. The mice were in separate woodchuck dens;
one mouse was 40 inches below the surface and the other was 26 inches
below the surface. The mice were curled up in the center of masses of
dead leaves, and thus, were well insulated against the cold. On April
29, 1944, at Ithaca, New York, Eadie (1949:307) uncovered a hibernating
jumping mouse. The nest, about the size of a baseball, was compactly
made of fine grasses and was 10 inches below the surface of the ground
in a mound of earth that was approximately six by four feet at the base
and three feet high.

From the foregoing reports on hibernation sites it is evident that well
drained areas are utilized. Sheldon (1934:300) remarks that the burrows
used for hibernating are dug in a bank or some place from which the rain
water and melted snow probably drains off.

Eadie (1949:307), Grizzell (1949:75), Sheldon (1934:299), Schwartz
(1951:228), and Sheldon (1938:331) all agree that the hibernating mouse
rolls up into a ball-like shape (resting on its head and pelvis) with
the head between the hind legs, the nose against the lower belly, the
forefeet curled on the chest, and the tail curled around the head and
body.

A marked loss of weight occurs immediately after hibernation begins,
and then reduction in weight is slow and regular. (See Hamilton,
1935:194 and Quimby, 1951:84.)

Sheldon (1934:297) cites a letter from Vernon Bailey in which he remarks
on the necessity of abundant moisture and saturate air for hibernating
jumping mice. Bailey writes "... they will awaken at times famished for
water and will drink and drink before going back to sleep."

Hamilton (1935:195) thinks that in the Ithaca area of New York these
mice probably leave their winter quarters in the second half of April
and that in southern New York and Long Island they emerge considerably
earlier. Quimby (1951:82) and Bernard Bailey (1929:163) report that
males appear earlier in the spring than do the females. Quimby (_loc.
cit._), by recording the sequence and dates of phenological events and
appearance of _Zapus_ in several years, was able to predict fairly
accurately the time of emergence of _Zapus_ in a succeeding year. In
Minnesota, jumping mice emerged late compared to other hibernating
rodents.

_Enemies._--V. Bailey (1927:119) reports that A. K. Fisher found 50
skulls of _Zapus_ in barn owl pellets taken from the towers of the
Smithsonian Institution, Washington, D. C. Dearborn (1932:32) reported
mink as having fed on jumping mice. Surface (1906:197) records taking a
_Zapus_ from the stomach of a rattlesnake. Pearson and Pearson
(1947:138) found remains of _Z. hudsonius_ in pellets of barn owls.
Quimby (1951:74) reports two cases of predation on _Z. hudsonius_; one
was by a northern pike, _Esox lucius_ Linnaeus and the other was by a
weasel, _Mustela_ sp. Vergeer (1948:91) collected a green frog, _Rana
clamitans_ Latreille, which had eaten a jumping mouse.

Quimby (1951:74) frequently found the fleas, _Megabothris quirini_
Rothschild, and _Megabothris wagneri_ (Baker), and occasionally a larval
tick, _Dermocenter variabilis_ (Say), on _Z. hudsonius_. Sheldon
(1934:296) remarks that captive animals are burdened with numerous
fleas. Hamilton (1935:191) removed a louse from a jumping mouse. One
mouse had a hole in the throat and three others had holes in the
inguinal region; presumably bot-flies had emerged from these holes. Test
(1943:507) found a single _Cuterebra_ larva in the inguinal region of a
_Z. hudsonius_, and Sheldon (1938:328) found _Z. hudsonius_ infested by
larvae of _Cuterebra fontinella_ Clark. Here, as in other cases, these
larvae were found immediately below the skin. Erickson (1938:252)
examined 18 _Z. hudsonius_ obtained in Minnesota, and found that three
were parasitized. He found a bot-fly larva, _Cuterebra_ sp., nematodes
of the genera _Subulura_ and _Spirocerca_, and a fluke of the genus
_Notocotylus_.

_Food._--Quimby (1951:85-86) studied the food preferences, by presenting
to caged _Z. hudsonius_ the plants and invertebrate animals normally
available to these mice in nature, and indicates that in general, the
starchy fruits of the Gramineae and the less fleshy fruits of various
groups of plants are more heavily utilized than other plant materials.
His observations indicate that these rodents are highly insectivorous
and that they consume many insects under natural conditions. Goodwin
(1935:148) reports that the stomach contents of several individuals
obtained at South Woodstock, Connecticut, consisted exclusively of
blackberries, and that others had subsisted principally on cranberries.
Hamilton (1935:197) remarks that seeds are the favored food but that
berries, nuts, fruits of various kinds, roots, and insects are also
utilized. Stoner (1918:123) writes that the food in cultivated areas of
Iowa is various grains as well as grass and weed seeds; in wooded places
the mice feed on seeds and nuts of trees. Vernon Bailey (1927:118)
states that the examination of a great many stomachs of these jumping
mice [in North Dakota] revealed nothing "but the fine white pulp of
carefully shelled, well-masticated seeds. Generally these are from
grasses, although grain and a variety of other plant seeds are eaten."
Schmidt (1931:116) examined the stomach contents of several _Z.
hudsonius_ taken in Clark County, Wisconsin, and in most stomachs found
the remains of finely chewed roots; however, two from Hewett had eaten
several geometrid caterpillars.

Lyon (1938:279), Stoner (1918:123), and J. W. Bailey (1946:263) present
information which indicates that _Z. hudsonius_ stores food in its nests
or burrows. Possibly these mice awaken at intervals from hibernation and
eat.

"These rodents characteristically seize the material to be eaten with
the front feet and devour it while reclining on their haunches. The
following observation of a caged animal is typical of their feeding
habits. The mouse selected a head of yellow foxtail, _Setaria glauca_
(Weig.) Stuntz, from several in the cage, separated it by gnawing
through the supporting stem, seized it with the front feet, held it up
to the mouth and began to gnaw at one end, stripping all parts from the
rachis. The grass head was slowly rotated and shifted sideways until
nothing remained but the rachis which was discarded. Actually the seeds
were the only parts eaten ..." (Quimby, 1951:73). Sheldon (1934:294)
remarks that _Z. hudsonius_ eats from a squatting position and holds the
piece of food in the forepaws. The mouse seems to bite off a seed, and
then, holding it in the forepaws, transfers it to the mouth.

According to Sheldon (_op. cit._:295) and Quimby (_loc. cit._), caged
jumping mice drink water. When drinking, the mouths of the mice are in
contact with the water, but neither observer determined whether the mice
lapped or sucked the water. Sheldon (_loc. cit._) observed these mice
passing stems of long grass through their mouths as though to squeeze
out moisture, and thought that the mice obtain most of their required
moisture from green plants.

_Reproduction._--The breeding season begins shortly after the jumping
mice emerge from hibernation in the spring, and reproduction continues
until a few weeks before they hibernate in the autumn. The extent of the
breeding period probably varies geographically and possibly seasonally.
For example, Quimby's (_op. cit._:70) information suggests that the 1947
period of parturition occurred between June 15 and August 30 in the area
of Centerville, Minnesota. In Michigan, Blair (1940:246) found a peak of
breeding activity in spring and another in late summer with little
activity in the intervening midsummer. Brimley (1923:263) records a
female in North Carolina, with eight embryos on June 13, 1895, and
another with seven embryos on September 17, 1891, indicating a strong
possibility of two litters per year there. Vernon Bailey (1927:118)
records young born in May or June in North Dakota and thinks that there
is time for only one litter per year. Petrides (1948:76) captured a
female on September 22, 1944, at Athens, Georgia, that gave birth to six
young on September 29. This late parturition date indicates a longer
breeding season in the southeastern part of the range of _Z. hudsonius_.

The gestation period of nonlactating, caged _Z. hudsonius_, Quimby
(1951:63) thinks, "is approximately 18 days ... [but] gestation is
prolonged in lactating females."

Data from museum labels indicate that embryos in 62 pregnant females
averaged 5.4 (2-8) per female. Quimby (1951:67) found the average number
of embryos per female for 14 females taken in Minnesota, to be 5.3 and
that litters of young found in nests averaged 5.8. Sheldon (1938:330)
reports two litters of seven young each and one of four young for _Z.
hudsonius_ in Vermont. Petrides (1948:76) records a litter of six young
for _Z. hudsonius_ in Georgia. Brimley (1923:263) records one lot of
seven and one lot of eight embryos for _Z. hudsonius_ in North
Carolina. Vernon Bailey (1923:120) reports six embryos for a female of
_Z. hudsonius_ taken in Washington, D. C. Ivor (1934:8) obtained a
litter of five young _Z. hudsonius_ from Erindale, Peel County, Ontario.
Hamilton (1935:195) records litters of two, four, and five young and
embryo counts of four, two, four, and four for _Z. hudsonius_ in New
York.

There seems to be two litters per year. According to Quimby (1951:69),
"most adult females breed soon after emergence from hibernation and
produce the first litters within a month. The remaining females do not
breed immediately but produce the first litter," he says, "in the second
month after emergence." Both early-breeding females and late-breeding
females produce at least 2 litters per year. Those that breed early may
have 3 litters.

The appearance and development of growing young of _Z. hudsonius_ in
successive weeks is described by Quimby (1951:65). Newborn young are
pink and hairless except for microscopic vibrissae. The eyes and
external auditory meatus are closed, and the pinnae are folded. The toes
are fleshy and clawless; the tail is short in relation to the length of
the body. The average weight was .78 grams. The average measurements of
three from different litters are: total length, 34 mm; tail, 9.2 mm;
hind foot, 4.7 mm. The young are helpless but capable of emitting a high
pitched squeaking sound which is audible for several feet.

In the first week of growth the vibrissae become visible to the naked
eye, the body changes to flesh color, the dorsal parts become dark gray,
the pinna unfolds and is black tipped, and the claws appear. The young
now are able to crawl and make a suckling noise, but they are not yet
able to support themselves on their legs.

In the second week of development, tawny yellow hair appears on the back
and spreads onto the sides. Sparse hair of a lighter color appears on
the belly, backs of the feet, and outer surfaces of the legs. Vibrissae
are now prominent. The eyes are still closed, but a crack down the
center of each is visible by the 13th day. Claws have grown, the longest
measuring 1.5 mm. The incisors erupt on approximately the 13th day,
those in the lower jaw appearing slightly before those in the upper jaw,
and all are white. Activity is increased; nevertheless the young still
crawl, make suckling notes, and squeak.

In the third week of development the mice are covered with hair; darker
hair appears dorsally; and vibrissae continue rapid growth. The external
auditory meatus begins to open on about the 19th day and young react to
sound on the 20th. The incisors now are 1 mm long and the claws 1.5 mm
long. Young are able to support themselves on their legs, walk, and make
one inch hops.

In the fourth week the juvenal pelage is replaced by adult pelage. The
eyes open between the 22nd and 25th days. The color of the incisors
changes from white to yellowish-orange as in the adults. P^4, M^1, M^2,
m1 and m2 have emerged from the maxillary and dentary bones; M^3 and m3
have not yet erupted. A mouse 33 days old had all teeth well developed.
By the end of the 4th week the young, except for size, are adultlike and
capable of independent existence.

The greatest increase in dimensions of the body is in the first four
weeks. A slowing down of growth is simultaneous with weaning.

Other workers, Sheldon (1938:330), Petrides (1948:76), and Ivor (1934:8)
also describe the appearance of the young.

Summer nesting sites are usually on the surface of the ground. Jumping
mice characteristically construct a globular nest of grass but will
utilize other vegetation if grasses are not available. Nests are usually
concealed under rocks, logs, bushes, or grass and can be entered by a
hole at one side.

Sheldon (1938:328) described a nest of _Z. hudsonius_ found on the
ground near the edge of a small hay field. The nest was globular, not
more than four inches in outside diameter and two inches in inside
diameter; it was closely woven of fine, dry grass and bits of moss.
Another nest found in the same field measured 11.5 inches in
circumference at the base and six inches in circumference over the top.
The inside width and length each was three inches, and the inside height
was 3.5 inches. Vernon Bailey (1927:118) remarks that summer nests are
placed on the surface of the ground well concealed under grass or other
vegetation. He describes the nest as "neat little balls of fine grass
with a tiny opening at one side and a soft lining in the central
chamber." Cory (1912:249) reports that summer nests are concealed behind
rocks or under bushes and thick grass. The nests are round and four or
five inches in diameter with an entrance hole at one side. Goodwin
(1935:148) examined a nest made entirely of straight, narrow leaves of
grass. Ivor (1934:8) found one made of finely shredded jute sacking.
Quimby (1951:80) describes several nests: one in the center of a rotten
willow log was lined with small pieces of pulpy wood; another was in the
rotted wood and debris, at ground level, inside a large, red oak (this
globular nest composed of grasses, plant fibers, and rootlets measured
six inches in diameter). Another nest was composed of a pile of wood
pulp, leaves of oaks, and grasses; this nest was in a hollow root
detached from a willow tree.

The mean home range of males, of _Z. hudsonius_ in Minnesota, according
to Quimby (1951:86), was 2.70 plus or minus .50 acres; this was
significantly larger than the mean home range of females, 1.57 plus or
minus .27 acres. According to Quimby (_loc. cit._), the size and shape
of the home range is influenced by the general features of the terrain,
density and type of cover, and land use in the immediate area. Quimby
(1951:94) remarked that the home range of the jumping mouse is
relatively unstable and Blair (1940:247) stated that the home ranges of
both sexes generally overlapped the ranges of other members of the same
species and sex. The average size of the home range for _Z. hudsonius_
in Michigan was .89 plus or minus .11 acres for males and .92 plus or
minus .11 acres for females.


=Zapus hudsonius acadicus= (Dawson)

    _Meriones acadicus_ Dawson, Edinburgh New Philos. Jour., new ser.,
        3:2, 1856.

    _Meriones labradorius_, Dawson, Edinburgh New Philos. Jour., new
        ser., 3:2, 1856.

    _Jaculus hudsonius_, Baird, Rept. Expl. and Surv...., 8
        (pt. 1):433, July 14, 1858 (part--the part from Nova Scotia,
        Vermont, and New York).

    _Zapus hudsonius_, Coues, Bull. U. S. Geol. and Geog. surv. of the
        territories, 2nd ser., No. 5:260, 1877 (part--the part from Nova
        Scotia, Vermont, and New York); Preble, N. Amer. Fauna, 15:17,
        August 8, 1899 (part--the part from New Brunswick, Nova Scotia,
        Maine, New Hampshire, Vermont, Massachusetts, and northeastern
        New York).

    _Zapus hudsonius canadensis_, Batchelder, Proc. New England Zool.
        Club, 1:5, February 8, 1899 (part--the part from Keene Valley in
        Essex County of New York, and Orivell in Vermont); Anderson, Ann.
        Rept. Provancher Soc. Nat. Hist., Quebec, 1941:35-37, July 14, 1942
        (part--the part from the tip of the Gaspé Peninsula in Quebec, New
        Brunswick, Maine, New Hampshire, Vermont, and New York).

    _Zapus hudsonius hardyi_, Batchelder, Proc. New England Zool. Club,
        1:6, February 8, 1899, type from Mt. Desert Island, Hancock County,
        Maine; Bole and Moulthrop, Sci. Publ. Cleveland Mus. Nat. Hist.,
        5:165, September 11, 1947 (part--but excluding Pennsylvania and
        Ohio).

    _Zapus hudsonius acadicus_, Anderson, Ann. Rept. Provancher Soc.
        Nat. Hist., Quebec, 1941:38, July 14, 1942.

_Type._--No type specimen designated. Subspecies characterized from
specimens obtained in Nova Scotia.

_Range._--Gaspé Peninsula of Quebec, New Brunswick, Nova Scotia, Prince
Edward Island, Maine, New Hampshire, Vermont, Massachusetts, northern
Connecticut and northeastern New York. See fig. 47. Zonal range:
Transition and Canadian.

_Description._--Size medium; back from near Ochraceous-Tawny to near
Yellow-Ocher with heavy admixture of black-tipped hair, the dorsal band
distinct against color of sides; sides lighter than back and from near
Cinnamon-Buff to near Ochraceous-Buff lined with black-tipped hair;
lateral line usually faintly marked but sometimes distinct and clear
Warm-Buff; underparts white, sometimes suffused with color of sides;
tail distinctly bicolored, brownish-black above and yellowish-white to
grayish-white below; ears dark, edged with color of sides; feet
grayish-white above; pterygoid fossae relatively narrow; zygomata
relatively long and broad; auditory bullae relatively narrow, usually
with depression on anterior surface; mastoid region relatively narrow;
inferior arm of zygomatic process of maxillary relatively narrow.

_Comparisons._--From _Zapus hudsonius canadensis_, _Z. h. acadicus_
differs in: Size averaging larger; upper parts usually less brownish and
more ochraceous, sides and flanks being more ochraceous and less
yellowish; zygomata relatively longer; pterygoid fossae relatively
narrower; auditory bullae relatively narrower and usually with
depression on anterior surface.

From _Zapus hudsonius americanus_, _Z. h. acadicus_ differs as follows:
Size larger; color darker on upper parts, flanks duller (less
ochraceous); underparts white, much less frequently suffused with color
of sides; ears dark, usually without flecks of ochraceous; general
appearance of pelage not so brightly colored; zygomata longer;
condylobasal length greater; mastoid region relatively broader; bullae
larger, more inflated and usually with depression on anterior surface;
maxillary tooth-row relatively longer.

For comparison with _Zapus hudsonius ladas_ see account of that
subspecies.

_Remarks._--Specimens from various localities in Nova Scotia, Prince
Edward Island and New Brunswick are essentially similar. Anderson
(1942:38) revived the name _Z. h. acadicus_ for jumping mice from these
areas, correctly considering them to be distinct from _Z. h.
canadensis_, the geographic race immediately to the west.

In the size and shape of the auditory bullae, length of the zygomata,
breadth of the pterygoid fossae, and general color of the pelage the
populations from Nova Scotia and New Brunswick are essentially
indistinguishable from material of _Zapus hudsonius hardyi_ from Maine.
Thus, _Z. h. hardyi_ must fall as a synonym of the earlier proposed name
_Z. h. acadicus_.

Bole and Moulthrop (1942:165) applied the name _Z. h. hardyi_ (=
_acadicus_) to the mice inhabiting a large area from coastal Maine and
central New Hampshire through southern New England, New York,
northwestern Pennsylvania, and northeastern Ohio. I agree with Bole and
Moulthrop (_loc. cit._) that the population of _Zapus hudsonius_ from
Maine, New Hampshire, west-central and northern New England are
different from neighboring subspecies and are referable to _Z. h.
acadicus_, but find that material from extreme southern Massachusetts,
Connecticut, southern New York, northwestern Pennsylvania, and
northeastern Ohio is best referred to _Zapus hudsonius americanus_ (see
account of that subspecies).

Intergradation between _Z. h. americanus_ and _Z. h. acadicus_ is
indicated by specimens from Berlin, Rensselaer County, New York. In
color of ears, length of zygomata, and size and shape of the incisive
foramina these specimens are more nearly like _Z. h. americanus_ but in
size and shape of the auditory bullae, breadth of the mastoid region,
and general appearance of the pelage they are more nearly like _Z. h.
acadicus_ and are here referred to _acadicus_. Specimens from Glenville,
Schenectady County, New York, are intermediate in cranial characters
between _Z. h. americanus_ and _Z. h. acadicus_ but in color are best
referred to the latter. Specimens from 1 mi. S Ayer, Worchester County,
Massachusetts, are like _Z. h. americanus_ in their short zygomata,
narrow mastoid region and suffusion of the underparts; nevertheless, in
the shape of the auditory bullae, breadth of the pterygoid fossae, and
greater condylobasal length the specimens are more nearly like _Z. h.
acadicus_ which they are here considered to be. Animals from Essex and
Wilmington, Essex County, Massachusetts, are like _Z. h. americanus_ in
external size and in the size and shape of the auditory bullae; but they
are more nearly like _Z. h. acadicus_ in most cranial characters and in
the general color of the pelage and are here assigned to _Z. h.
acadicus_.

Specimens from Keene Valley, Essex County, New York, considered by
Batchelder (1899:4) to be _Z. h. canadensis_, are in color, length of
the zygomata, and size and shape of the auditory bullae more nearly like
_Z. h. acadicus_ to which subspecies they are here assigned. A specimen
from Orwell, Addison County, Vermont, that Batchelder (_op. cit._:5)
referred to _Z. h. canadensis_ is more nearly like _Z. h. acadicus_ in
the shape of the auditory bullae, length of the zygomata, and color of
the pelage, and is here referred to _Z. h. acadicus_. Specimens from
western New Brunswick, referred to _Z. h. canadensis_ by Anderson
(1942:37), are more nearly like _Z. h. acadicus_. Specimens from Ste.
Anne des Monts, Gaspé Peninsula, Quebec, are intermediate between _Z. h.
canadensis_ and _Z. h. acadicus_ in color and size and also in the shape
of the auditory bullae but are best referred to _Z. h. acadicus_.

_Zapus hudsonius acadicus_ as here understood is a relatively
wide-ranging subspecies. Populations at the southern periphery of its
range are difficult to separate from populations at the northern
periphery of the range of _Z. h. americanus_. These two geographic races
represent opposite extremes of a clinal gradient and, as would be
expected, geographic intermediates are morphologically similar.

_Specimens examined._--Total, 156, distributed as follows:

MAINE: _Aroostock County_: _Madawaska_, 6 (MCZ). _Hancock County_:
_Mount Desert Island_, 9 (6 MCZ, 3 UM). _Piscataquis County_: _Mount
Katahdin_, 1 (USNM); Sebec Lake, 4 (USBS); _Katahdin Lake_, 1 (USBS).
_Sagadahoc Co._: Small Point Beach, 1 (Clev. MNH). _Somerset County_:
east branch Penobscot River, 2 (USBS). _Washington County_: Columbia
Falls, 1 (USBS).

MASSACHUSETTS: _Essex County_: _Essex_, 4 (Clev. MNH); Wilmington, 4 (3
USBS, 1 USNM). _Worchester County_: _Lunenberg_, 2 (USBS); _1 mi. S
Ayer_, 2 (MVZ); 2 mi. N Gilbertville, 1.

NEW BRUNSWICK: _Charlotte County_: _6 mi. N St. Andrews_, 2 (NMC); 5 mi.
N St. Andrews, 4 (NMC). _Carleton County_: _Debec_, 1 (MVZ). _Gloucester
County_: Dalhousie, 2 (MVZ); _Miramichi Road, 15 mi. from Bathurst_, 4
(NMC); _Youghall_, 3 (NMC). _Madawaska County_: Baker Lake, 2 (NMC); _9
mi. NE Edmundston_, 4 (NMC); 5 mi. N St. Leonard, 5 (NMC). _Victoria
Co._: _Tobique Point_, 1 (AMNH). _York County_: _Queensbury_, 1 (USBS).

NEW HAMPSHIRE: _Carroll County_: _Intervale_, 1 (UM); _Ossipee_, 4 (3
USBS); _2 mi. S Ossipee_, 12 (2 USNM). _Coos County_: _Nathan Pond_, 1
(UM); Fabyans-Bretton Woods, Dartmouth Brook, 2 (UM); _Fabyans_, 1
(USNM); _3 mi. W Base Station_, 1; _Mt. Washington_, 1 (MVZ); _Pinkham
Notch, 1900 ft._, 1 (USNM). _Grafton County_: _Franconia Notch, Profile
Lake_, 1 (UM); Lebanon, 3 (UM). _Strafford Co._: _1 mi. E Durham_, 1
(UM).

NEW YORK: _Essex Co._: Keene Valley, 5 (MCZ); _Keene Heights_, 5 (MCZ);
_Minerva, 1700 ft._, 1 (AMNH). _Herkimer County_: Northwood, 7 (AMNH).
_Rensselaer Co._: Berlin, 8 (AMNH). _Schenectady County_: _Glenville_, 1
(USBS). _Warren County_: _Lake George_, 5 (USBS). _Washington County_:
_Patterns Mills_, 1 (USBS).

NOVA SCOTIA: _Annapolis Co._: Bear River, 7 (NMC); _Lake Kedgemakooge_,
5 (UM); 2 mi. S Milford, 1 (AMNH). _Kings Co._: Black River Dist., 1
(NMC); _no exact locality_, 1 (NMC). _Shelburne County_: Doctors Cove, N
Barrington Passage, 1 (NMC); _Barrington Passage_, 4 (NMC).

PRINCE EDWARD ISLAND: no exact locality, 1 (USBS).

QUEBEC: Ste. Anne des Monts, 1 (AMNH).

VERMONT: _Addison County_: Orwell, 1 (MCZ); _Lamville County_: Mt.
Mansfield, 2 (USBS). _Windham County_: _Whitingham_, 2 (AMNH).

_Marginal records._--Quebec: Ste. Anne des Monts. New Brunswick:
Dalhousie. Prince Edward Island. Nova Scotia: Black River District;
Doctors Cove, N Barrington Passage. Maine: Columbia Falls; Small Point
Beach. Massachusetts: Wilmington; 2 mi. N Gilbertville. New York:
Berlin; North Wood; Keene Valley. Maine: E branch Penobscot River. New
Brunswick: Baker Lake.


=Zapus hudsonius alascensis= Merriam

    _Zapus hudsonius alascensis_ Merriam, Proc. Biol. Soc. Washington,
        2:223, July 15, 1897.

    _Zapus hudsonius hudsonius_, Osgood, N. Amer. Fauna, 24:37,
        November 23, 1904.

_Type._--Male, adult, skin and skull, No. 73584, U. S. Nat. Mus., Biol.
Surv. Coll.; Yakutat Bay, Alaska; obtained on July 5, 1895, by Clark P.
Streator, original No. 4660.

_Range._--Alaska Peninsula, coastal section of mainland of southern and
southeastern Alaska including Revillagigedo Island; also southwestern
Yukon. See fig. 47. Zonal range: Canadian and Hudsonian.

_Description._--Size large; back from near Ochraceous-Tawny to near
Dresden Brown, sometimes darkened with black tipped hair usually with
darker mid-dorsal area forming a band; sides lighter than back and from
near Ochraceous-Tawny to near Clay Color; lateral line usually distinct,
of clear Ochraceous-Buff; belly white, frequently with a slight
suffusion of Ochraceous-Buff; tail bicolored, brownish to brownish-black
above, white to yellowish-white below; ears dark, edged and flecked on
the inner surface with color of sides; feet grayish-white above;
auditory bullae broad and moderately inflated; pterygoid fossae
relatively broad; incisive foramina relatively long, zygomata relatively
long and broadly bowed; mastoid region relatively broad; distance from
incisors to postpalatal notch relatively great; occipitonasal length
relatively great.

_Comparisons._--From _Zapus hudsonius tenellus_, _Z. h. alascensis_
differs as follows: Size larger; upper parts darker, less ochraceous;
sides duller, less ochraceous more tawny; incisive foramina averaging
longer; mastoid region broader; occipitonasal length greater; zygomata
wider-spreading and longer; condylobasal length averaging greater;
auditory bullae less broadly rounded; and distance from incisors to
postpalatal notch averaging greater.

For comparison with _Zapus hudsonius hudsonius_ see account of that
subspecies.

_Remarks._--_Zapus hudsonius alascensis_ is a fairly well marked
subspecies retaining most of its characters throughout its range.
Variation is noted in specimens from the southwest end of Dezadeash
Lake, 2400 ft., Yukon Territory, and seems to be the result of
intergradation between _Zapus hudsonius hudsonius_ and _Z. h.
alascensis_. These animals are like _Z. h. hudsonius_ in the shape of
the auditory bullae but are otherwise more nearly like _Z. h.
alascensis_ to which they are here assigned. Alaskan specimens from 7
mi. SSE Haines, and from a point 9 mi. W and 4 mi. N Haines average
slightly larger than _Z. h. alascensis_ in most measurements taken;
however, in coloration they more nearly agree with _Z. h. alascensis_
than with _Z. h. hudsonius_ or _Z. h. tenellus_ the geographic ranges of
which adjoin that of _Z. h. alascensis_.

_Specimens examined._--Total, 56, distributed as follows:

ALASKA: Cook Inlet, Tyonek, 1 (USBS); head Chalitna River, 2 (USBS);
Lake Clark, 4 (USBS); east side Chilkat River, 100 ft., 9 mi. W and 4
mi. N Haines, 8; Yakutat, 3 (USBS); Lake Iliamma, 1 (USBS); Lake
Aleknagik, 1 (USBS); _Kokwok_, 1 (USBS); _Nushagak River_, 3 (USBS);
_Chilkat Peninsula, 10 ft., 7 mi. SSE Haines_, 18; Nushagak, 3 (USBS);
Chignik Bay, 1 (USBS); Portage Cove, Revillagigedo, 1 (MVZ); _Izembek
Bay_, 1 (USBS); Frosty Peak, 1 (USBS).

BRITISH COLUMBIA: _west end Kelsall Lake, 2900 ft._, 1; Stonehouse
Creek, 5-1/2 mi. W junction Stonehouse Creek and Kelsall River, 4.

YUKON: SW end Dezadeash Lake, 2400 ft., 2.

_Marginal records._--Alaska: Lake Aleknagik; head Chalitna River. Yukon:
SW end Dezadeash Lake, 2400 ft. Alaska: E side Chilkat River, 100 ft., 9
mi. W and 4 mi. N Haines; Portage Cove, Revillagigedo Island; Yakutat;
Cook Inlet, Tyonek; Chignik Bay; Frosty Peak.


=Zapus hudsonius americanus= (Barton)

    _Dipus americanus_ Barton, Trans. Amer. Philos. Soc., 4:115, 1799.

    _Jaculus americanus_ Wagler, Nat. Syst. Amphibien, 23, 1830.

    _Meriones microcephalus_ Harlan, Proc. Zool. Soc. London, p. 1,
        1839, based on two specimens from "the farm of Mr. Beck, in
        Philadelphia County, a few miles northeast of the city [=
        Philadelphia, Pennsylvania]."

    _Jaculus hudsonius_, Baird, Repts. Expl. and Surv. 111, 8 (pt. 1):
        433, July 14, 1858 (part--the part from Massachusetts, Connecticut,
        New York, New Jersey, and Pennsylvania).

    _Zapus hudsonius_, Coues, Bull. U. S. Geol. and Geog. Surv. of the
        territories, 2nd ser. No. 5:260, 1877 (part--the part from
        Massachusetts, Connecticut, New York, and Pennsylvania); Preble,
        N. Amer. Fauna, 15:17, August 8, 1899 (part--the part from
        Peterboro and Waterville, New York, southeastern Massachusetts,
        Connecticut, New Jersey, Pennsylvania, West Virginia, Maryland,
        North Carolina, and Ohio).

    _Zapus hudsonius americanus_, Batchelder, Proc. New England Zool.
        Club, 1:6, February 8, 1899; Preble, N. Amer. Fauna, 15:19,
        August 8, 1899.

    _Zapus hudsonius hardyi_, Bole and Moulthrop, Sci. Publ. Cleveland
        Mus. Nat. Hist., 5:165, September 11, 1942 (part--the part from
        New York, Ohio, and Pennsylvania).

    _Zapus hudsonius brevipes_ Bole and Moulthrop, Sci. Publ. Cleveland
        Mus. Nat. Hist., 5:168, September 11, 1942, type from Bettsville,
        Seneca County, Ohio.

    _Zapus hudsonius rafinesquei_ Bole and Moulthrop, Sci. Publ.
        Cleveland Mus. Nat. Hist., 5:169, September 11, 1942 (part--the
        part from southeastern Ohio), type from Cat Run, extreme
        southeastern Belmont County, Ohio.

_Type._--No type specimen designated. _Dipus americanus_ was
characterized from jumping mice obtained by Barton near the Schuylkill
River, a few miles from Philadelphia, Pennsylvania.

_Range._--Southeastern United States and lower peninsula of Michigan;
east of central Indiana; from central New York and Massachusetts
southward to northern Georgia. See fig. 47. Zonal range: Austroriparian
(Lower Austral), Carolinian (Upper Austral), Alleghanian (Transition),
and Canadian.

_Description._--Size small; back from near Light Ochraceous-Buff to near
Ochraceous-Buff with admixture of black-tipped hair forming distinct
dorsal band; sides bright, lighter than back from near Light
Ochraceous-Buff to near Ochraceous-Buff; lateral line usually distinct
and of color of sides; underparts white, sometimes with slight suffusion
of color of sides; tail bicolored, brown to brownish-black above,
yellowish-white to grayish-white below; ears narrowly edged and heavily
flecked with color of sides; feet white to grayish-white above; skull
short; braincase relatively narrow; incisive foramina relatively broad;
skull relatively narrow across zygomata; interorbital region relatively
broad; distance from incisors to postpalatal notch relatively short;
auditory bullae relatively small.

_Comparisons._--Compared with _Zapus hudsonius canadensis_, _Z. h.
americanus_ differs as follows: Smaller; paler (in a sense brighter
because more ochraceous and less tawny); skull smaller; auditory bullae
narrower, less inflated; incisive foramina relatively more bowed;
condylobasal length averaging less.

From _Zapus hudsonius intermedius_, _Z. h. americanus_ differs as
follows: Smaller; color brighter, more ochraceous, less yellow;
braincase relatively narrower; auditory bullae usually smaller; incisive
foramina broader; inferior ramus of zygomatic process of maxillary
usually with median projection; interorbital region averaging broader.

For comparison with _Zapus hudsonius acadicus_ see account of that
subspecies.

_Remarks._--Intergradation with _Zapus hudsonius acadicus_ occurs in
southeastern New York as indicated by a series of 25 specimens from
Peterboro. They resemble _Z. h. acadicus_ in width of the mastoid
region and relatively longer tooth-row, but in the size and shape of the
auditory bullae, width of the pterygoid fossae, and lighter, brighter,
color of the sides they are more nearly like _Z. h. americanus_ to which
they are here referred.

Intergradation between _Z. h. americanus_ and _Z. h. acadicus_ is
indicated also by specimens from Lawyersville and Schoharie, New York.
In animals from both localities the length of the zygomata and the
breadth of the mastoid region are more nearly as in _Z. h. acadicus_,
but in size and shape of the auditory bullae, over-all length of the
skull, color of the ears, and general color of the pelage they are more
nearly like _Z. h. americanus_ to which they are here referred.

Specimens from western Pennsylvania, judged to be _Z. h. hudsonius_ by
Preble (1899:17), and those from northwestern Pennsylvania and
northeastern Ohio, allocated to _Z. h. hardyi_ (= _acadicus_) by Bole
and Moulthrop (1942:165), are more nearly like _Z. h. americanus_ in
size and shape of the auditory bullae, short zygomata, relatively narrow
mastoid region, and color of pelage.

Specimens from the lower peninsula of Michigan, northeastern Indiana,
and northwestern Ohio, described by Bole and Moulthrop (_op. cit._:168)
as belonging to a new subspecies (_Zapus hudsonius brevipes_), are to me
indistinguishable from most specimens of _Z. h. americanus_. The
characters which Bole and Moulthrop (_loc. cit._) ascribe to _Z. h.
brevipes_--color bright Ochraceous-Buff, tail and hind feet short, and
skull narrow--are also those of _Z. h. americanus_.

Specimens from various localities in southeastern Ohio, all within the
range ascribed by Bole and Moulthrop (_op. cit._:169) to _Zapus
hudsonius rafinesquei_, are indistinguishable from specimens of _Z. h.
americanus_ from eastern Tennessee, West Virginia, North Carolina, and
Maryland. _Zapus hudsonius rafinesquei_ (at least that part from
southeastern Ohio) is indistinguishable from _Z. h. americanus_ and
therefore is synonymized under _Z. h. americanus_.

Specimens from Lagrange County, Indiana, show intergradation between
_Zapus hudsonius intermedius_ and _Z. h. americanus_ in the color of the
pelage but are more nearly like _Z. h. americanus_ to which they are
here referred. One from Porter County, Indiana, is more nearly like _Z.
h. intermedius_ in size and shape of the bullae and in breadth of the
pterygoid fossae but in color and degree of lateral bowing of the
zygomata is better placed with _Z. h. americanus_.

_Z. h. americanus_ is a wide ranging subspecies. Animals at the northern
periphery of the range (lower peninsula of Michigan to the west and
southeastern Massachusetts to the east) are largest and darkest; to the
southward there is a progressive reduction in size and a change to a
lighter, brighter color. Animals from Maryland, Virginia, and North
Carolina are more nearly average representatives of the subspecies than
are those from the region of the type locality.

A jumping mouse allegedly of this subspecies has been recorded by
Coleman (1941:91) from Caesars Head, 300 ft., South Carolina. This
specimen and one from Athens, Georgia, provide the southeasternmost
record-stations of occurrence for the species _Z. hudsonius_.

_Specimens examined._--Total, 318, distributed as follows:

CONNECTICUT: _Hartford County_: _Windsor_, 1 (USBS); _East Hartford_, 2
(MCZ). _Litchfield County_: Sharon, 3 (AMNH); _Macedonia Park_, 2
(AMNH). _Middlesex County_: _Clinton_, 1 (AMNH). _Windham County_: South
Woodstock, 10 (AMNH); _Pomfret, near Hampton line_, 1.

GEORGIA: _Clarke Co._: Athens, 1 (USBS).

INDIANA: _Lagrange Co._: no exact locality, 2 (UM). _Porter Co._:
Mineral Springs, 1 (FM); _no exact locality_, 1 (FM).

MARYLAND: _Anne Arundel County_: _Patuxent Research Refuge_, 1 (USBS).
_Charles County_: _no exact locality_, 1 (USBS). _Garrett Co._: Finzel,
6 mi. N Frostburg, 1 (USBS). _Montgomery County_: _Sandy Springs_, 2
(USBS); _Kensington_, 1 (USNM); _Cabin John Bridge_, 2 (1 USBS; 1 USNM).
_Prince Georges County_: _Laurel_, 8 (USNM); _Branchville_, 1 (USBS);
_College Park_, 1. _Worchester County_: Assateague, 5 mi. S Ocean City,
1 (USBS).

MASSACHUSETTS: _Barnstable County_: _West Falmouth_, 1 (USBS). _Bristol
County_: _Raynham_, 1 (Clev. MNH). _Dukes County_: _Martha's Vineyard_,
1 (USBS); _West Chop, Martha's Vineyard_, 1 (Clev. MNH). _Nantucket
County_: _Nantucket Island_, 1 (USNM). _Plymouth County_: Middleboro, 1
(USNM); _Plymouth_, 1 (UM); _Marshfield_, 6 (USBS); _Wareham_, 3 (1
Clev. MNH; 2 UM).

MICHIGAN: _Alcona Co._: _2 mi. S Harrisville_, 2 (UM). _Allegan Co._:
_near junction Swan Creek and Kalamazoo River_, 3 (UM). _Berrien Co._:
_Warren Woods_, 2 (UM); _Three Oaks_, 1 (UM). _Charlevoix Co._: _Thumb
Lake_, 1 (UM); _Section 1 Norwood Township_, 1 (UM); _Boyne Falls_, 12
(UM); _2 mi. S Boyne Falls_, 2 (UM). _Cheboygan Co._: Douglas Lake, 2
(UM). _Clinton Co._: _2 mi. SE DeWitt_, 1 (UM). _Emmet Co._: _Maple
River, near Douglas Lake_, 1 (UM). _Huron Co._: _Rush Lake_, 1 (UM).
_Kalamazoo Co._: _no exact locality_, 1 (UM). _Lake Co._: _1 mi. NW
Chase_, 1 (UM). _Livingston Co._: _George Reserve, Pinckney_, 2 (UM);
_Upper Whitewood Lake_, 1 (UM); _Whitmore Lake_, 1 (UM); _Portage Lake_,
3 (UM). _Mason Co._: 9 mi. N Ludington, 1 (UM). _Midland Co._: Sanford,
1 (UM). _Montmorency Co._: _T. 32N, R. 1E, Sec. 30_, 1 (UM). _Muskegon
Co._: _4 mi. NW North Muskegon_, 2 (UM). _Oakland Co._: Bloomfield, 1
(UM); _no exact locality_, 1 (UM). _Otsego Co._: _Pigeon River_, 1 (UM);
_T. 32N, R. 1W, Sec. 25_, 1 (UM); _Waters_, 1. _Roscommon Co._: _T. 24N,
R. 2W, Sec. 2_, 1 (UM). _Shiawassee Co._: _1/2 mi. NE Byron_, 5 (UM);
_1/4 mi. S Byron_, 2 (UM); _2 mi. SE Byron_, 1 (UM); _3 mi. SW Byron_, 1
(UM). _Van Buren Co._: _Van Auken Lake_, 1 (UM). _Washtenaw County_:
_Whitmore Lake_, 1 (UM); _2 mi. W Cherry Hill_, 1 (UM); _Ann Arbor_, 7
(UM); _2 mi. E Ann Arbor_, 2 (UM); _Willow Run Village_, 1 (UM).

NEW JERSEY: _Bergen County_: Harrington Park, 1 (AMNH); _Englewood_, 1
(USNM). _Cape May County_: _Mays Landing_, 3 (Clev. MNH). _Morris
County_: _Mendham_, 1 (AMNH). _Ocean County_: Tuckerton, 3 (USBS).

NEW YORK: _Broome Co._: _5 mi. N Binghamton_, 2 (USNM). _Cayuga County_:
E Aurora, 1 (USBS). _Greene County_: Catskills, 4 (USNM); _Kaaterskill
Junction_, 1 (USNM). _Madison County_: Peterboro, 25 (2 MCZ; 19 USNM; 4
Clev. MNH). _Nassau County_: Locust Grove, 3 (USNM). _Orange Co._:
_Cranberry Pond, 840 ft., Highland_, 2 (USNM). _Otsego County_: _Lake
Charlotte_, 1 (AMNH). _Queens County_: _Woodside, Long Island_, 1
(USNM); _near Forest Hills, Long Island_, 1 (AMNH); _Ray Nu Beach, Long
Island_, 1 (USNM). _Rockland County_: _Tappan_, 1 (AMNH). _Schoharie
County_: _Lawyersville_, 1 (AMNH); _Schoharie_, 1 (AMNH). _Suffolk
County_: _Montauk Point, Long Island_, 8 (USBS). _Tioga County_:
_Owego_, 1 (USBS). _Westchester Co._: _Bedford_, 1 (AMNH).

NORTH CAROLINA: _Buncombe County_: _Weaverville_, 1 (AMNH). _Cherokee
Co._: Martin Creek, 2 (UM). _Mitchell County_: Roan Mountain, 2 (USBS).
_Wake County_: Raleigh, 5 (3 USNM; 1 UM; 1 NCS).

OHIO: _Carroll Co._: Carrollton, 2 (UM). _Cuyahoga County_: _Big Creek,
Brookside Park_, 1 (Clev. MNH); _Dover_, 1 (Clev. MNH); _Rocky River
Metr. Park_, 3 (Clev. MNH); _North Olmstead_, 1 (Clev. MNH). _Erie Co._:
_Milan_, 1 (Clev. MNH); _Mill Hollow, Vermilion River_, 1 (Clev. MNH).
_Lake Co._: Holden Arboretum, 3 (Clev. MNH). _Meigs Co._: Portland
Station, 1 (Clev. MNH). _Seneca Co._: _Bettsville_, 4 (Clev. MNH); Old
Fort Seneca, 4 (Clev. MNH); _Corners_, 1 (Clev. MNH). _Wayne Co._:
_Wooster_, 1 (UM); _Craighton_, 1 (UM).

PENNSYLVANIA: _Beaver Co._: _1 mi. NE Darlington_, 1 (CM); _2 mi. E
Industry_, 1 (CM); _4 mi. E Frankfort_, 2 (CM). _Bedford Co._: _1 mi. NE
Osterburg_, 1 (CM). _Berks Co._: _2 mi. W Strausstown_, 1 (USNM).
_Bradford Co._: _2-1/2 mi. NNW Wyalusing_, 2 (CM). _Bucks Co._: 2 mi. N
New Britain, 1 (CM). _Butler Co._: _Thorn Creek, 4 mi. S Butler_, 4
(CM); _2 mi. E Middle Lancaster_, 1 (CM); _Orphans Home, 2 mi. E Mars_,
2 (CM). _Cambria Co._: _2-1/2 mi. S Patton, 1750 ft._, 1 (CM); _5-1/2
mi. NE Ebensburg_, 1 (CM). _Centre Co._: 2, mi. E Snowshoe, 2 (CM).
_Chester Co._: _2 mi. S West Chester_, 1 (CM). _Clinton Co._: _Tamarack,
9 mi. NNW Renovo_, 1 (CM). _Crawford Co._: _Pymatuning Lake_, 3 (Clev.
MNH). _Erie Co._: _4-1/2 mi. SW_ [town of] _North East_; 2 (CM); _East
Springfield_, 1 (CM). _Fulton Co._: _1-1/2 mi. NE Warfordsburg, 580
ft._, 1 (CM). _Huntington Co._: _6-1/2 mi. S Shade Gap_, 2 (CM).
_Indiana Co._: _1/2 mi. E Indiana, 1320 ft._, 2 (CM). _Lebanon Co._:
_1-1/2 mi. SE Cornwall, 800 ft._, 1 (CM). _Mercer Co._: _2-1/2 mi. W
Mercer_, 2 (CM); _5 mi. S Mercer_, 1 (CM). _Monroe Co._: _Pocene Lake_,
1(CM). _Pike Co._: _Bruce Lake_, 1 (CM). _Potter Co._: _Woodcock Run,
7-1/2 mi. WSW Ulysses_, 2 (CM). _Sommerset County_: _4 mi. SW Somerset,
2100 ft._, 2 (CM); _New Lexington_, 1 (USBS). _Susquehanna Co._: 10 mi.
NNW Montrose, 1 (CM). _Union Co._: _Glen Iron_, 2 (CM). _Warren Co._:
Bensons Swamp, 5 mi. E Columbus, 1 (USNM); _Miles Run, 5 mi. NW
Pittsfield_, 1 (CM); _1-1/2 mi. N Pittsfield_, 1 (CM); _2-1/2 mi. N
Kinzua_, 2 (CM); _2 mi. N Kinzua_, 1 (CM).

TENNESSEE: _Carter Co._: 3 mi. SSW Roan Mountain (town), 2900 ft., 1
(UM).

VIRGINIA: _Amelia Co._: Amelia, 1 (UM). _Elizabeth City County_: Near
Hampton, 2 (UM). _Fairfax County_: Fall Church, 4 (2 USNM; 2 USBS);
_opposite Plummers Island, Maryland_, 1 (USNM). _Highland Co._: Laurel
Park, 9 mi. NNW Monterey, 3100 ft., 4 (UM). _Nelson Co._: _no exact
locality_, 5 (USNM). _Norfolk County_: _Deep Creek_, 1 (USBS). _Page
Co._: _no exact locality_, 1 (USNM). _Smyth Co._: _Sugar Grove_, 1 (UM);
_1/2 mi. E Konnarock, 2800 ft._, 1 (UM). _Washington Co._: Konnarock,
2900 ft., 1 (UM).

WASHINGTON D. C.: _Chevy Chase_, 1 (USBS); _no exact locality_, 4 (3
USNM; 1 USBS).

WEST VIRGINIA: _Monongalia Co._: Morgantown, 6.

_Marginal records._--Michigan: Douglas Lake; Bloomfield. New York: E
Aurora; Peterboro; Catskills. Connecticut: Sharon; South Woodstock.
Massachusetts: Middleboro. New Jersey: Tuckerton. Maryland: Assateague,
5 mi. S Ocean City. North Carolina: Raleigh. Georgia: Athens. Indiana:
Mineral Springs. Michigan: 9 mi. N Ludington.


=Zapus hudsonius campestris= Preble

    _Zapus hudsonius campestris_ Preble, N. Amer. Fauna, 15:20, August
        8, 1899.

_Type._--Male, adult, No. 65872 U. S. Nat. Mus., Biol. Surv. Coll.; Bear
Lodge Mt's [Crook County], Wyoming; obtained on June 21, 1894, by B. H.
Dutcher, original No. 600.

_Range._--Southeastern Montana, southwestern South Dakota, and
northeastern Wyoming. See fig. 47. Zonal range: Transition.

_Description._--Size large; back from near Ochraceous-Tawny to near
Ochraceous-Buff with admixture of black tipped hair forming distinct
dorsal band; sides lighter than back, from near Ochraceous-Buff to near
Yellow Ocher with black hair interspersed; lateral line usually
distinct, of clear Ochraceous-Buff; belly white, usually with moderate
suffusion of Ochraceous-Buff; tail bicolored, brownish to brownish-black
above, grayish-white to yellowish-white below; ears dark, edged with
Ochraceous-Buff; feet grayish-white above; auditory bullae large, well
inflated; incisive foramina long and usually truncate at posterior
border; pterygoid fossae broad; zygomata relatively wide-spread and
long; large medial projection on inferior ramus of zygomatic process of
maxillary; condylobasal length and occipitonasal length relatively
great; mastoid region and palatal region relatively broad; interparietal
bone usually broad.

_Comparisons._--From _Zapus hudsonius pallidus_, _Z. h. campestris_
differs as follows: Coloration darker (more black and yellow but less
orange); averaging larger in all measurements taken except in least
interorbital constriction and distance from incisors to postpalatal
notch which are slightly larger and breadth across zygomatic arches
which is same; zygomatic arch heavier; incisive foramina larger;
interparietal bone broader.

Compared with _Zapus hudsonius intermedius_, _Z. h. campestris_ differs
as follows: Coloration more tawny and ochraceous, less yellow; auditory
bullae averaging larger, more inflated; condylobasal length averaging
greater; zygomata averaging more wide-spread and longer; distance from
incisors to postpalatal notch averaging longer; mastoid region broader;
incisive foramina longer and more truncate posteriorly.

From _Zapus hudsonius hudsonius_, _Z. h. campestris_ differs as follows:
Size larger; color lighter, more ochraceous, less tawny; occipitonasal
length averaging greater; mastoid region broader; zygomata averaging
longer; zygomatic arch more widely bowed; distance from incisors to
postpalatal notch averaging longer; incisive foramina longer; auditory
bullae broader, more inflated.

For comparison with _Zapus hudsonius preblei_ see account of that
subspecies.

_Remarks._--Animals from the Black Hills of South Dakota and Wyoming are
thought of as most characteristic of this geographic race.
Intergradation is noted with _Zapus hudsonius pallidus_ and is discussed
in the account of that subspecies.

_Specimens examined._--Total, 66, distributed as follows:

MONTANA: _Big Horn County_: Rotten Grass Creek, north base Big Horn
Mts., 2 (USBS); _Little Big Horn River, 2 mi. from Wyoming line_, 1
(USBS).

SOUTH DAKOTA: _Custer County_: _Custer_, 3 (USNM); Bull Springs, 6
(Clev. MNH); _Beaver Creek, Wind Cave Nat'l Park_, 1 (UM); Wind Cave
Nat'l Park Game Ranch, Cold Spring Creek, Wind Cave Nat'l Park, 2 (UM);
_Pennington County_: _Rapid Creek, 2 mi. W Pactola, 4800 ft._, 3 (UM);
Castle Creek, R. 2E, T. 1N, 6500 ft., 3 (UM); Nelsons Place, 3 mi. SE
Hill City, 6 (UM); _Palmer Gulch, 4 mi. SE Hill City_, 3 (UM); _Palmer
Gulch_, 9 (FM); _no definite locality_, 4 (UM).

WYOMING: _Crook County_: Devils Tower, flood plain Belle Fourche River,
3350 ft., 1 (USBS); Bear Lodge Mts., 4 (USBS); _15 mi. N Sundance, Black
Hills Nat'l Forest, 5500 ft._, 2; _3 mi. NW Sundance, 5900 ft._, 17;
_Sundance_, 2 (USBS). _Weston Co._: 1-1/2 mi. E Buckhorn, 6150 ft., 5.

_Marginal records._--Montana: Rotten Grass Creek, N base Big Horn Mts.
South Dakota: Nelsons Place, 3 mi. SE Hill City; Wind Cave Nat'l Park
Game Ranch, Cold Spring Creek. Wyoming: 1-1/2 mi. E Buckhorn, 6150 ft.


=Zapus hudsonius canadensis= (Davies)

    _Dipus canadensis_ Davies, Trans. Linn. Soc. London, 4:157, 1798.

    _Zapus hudsonius hudsonius_, Preble, N. Amer. Fauna, 15:17, August
        8, 1899 (part--the part from Ontario).

    _Zapus hudsonius canadensis_, Batchelder, Proc. New England Zool.
        Club, 1:5, February 8, 1899 (part--the part from Quebec); Anderson,
        Rept. Provancher Soc. Nat. Hist., Quebec, 1941:35-37, July 14, 1942
        (part--the part from Quebec excepting the Gaspé Peninsula).

    _Zapus hudsonius ontarioensis_ Anderson, Ann. Rept. Provancher Soc.
        Nat. Hist., Quebec, 1942:59, September 7, 1943, type from Pancake
        Bay (Batchawana Bay) southeast end of Lake Superior, Algoma
        District, about 40 miles northeast of Sault Ste-Marie, Ontario.

_Type._--No type specimen designated, subspecies characterized on the
basis of two specimens obtained by Major General Thomas Davies within a
few miles of the city of Quebec.

_Range._--Eastern Ontario and western Quebec from Hudson Bay southward
to the Great Lakes and into northwestern New York. See fig. 47. Zonal
range: Transition and Canadian.

_Description._--Size medium; back from near Clay Color to near
Cinnamon-Buff with admixture of black hair usually forming a dorsal
band; sides from near Clay Color to near Cinnamon-Buff and lighter than
back; lateral line usually distinct, and clear Cinnamon-Buff; belly
white, sometimes with slight suffusion of Cinnamon-Buff mid-ventrally;
tail bicolored, brownish to brownish-black above, grayish-white to
yellowish-white below; ears dark, sometimes flecked with color of the
sides, edged with Cinnamon-Buff; feet grayish-white above; auditory
bullae large, relatively broad and flat; incisive foramina relatively
short and narrow, widest posteriorly; zygomata not widely bowed outward;
mastoid region relatively wide; frontal region well inflated; nasals
relatively narrow, short, and parallel sided.

_Comparisons._--From _Zapus hudsonius hudsonius_, _Z. h. canadensis_
differs as follows: Upper parts generally dull averaging lighter, less
black tipped hair; sides also lighter with less suffusion of dark hair;
frontal region more inflated; mastoid region averaging broader; auditory
bullae broader; distance from incisors to postpalatal notch averaging
slightly longer.

For comparison with _Zapus hudsonius acadicus_, _Zapus hudsonius ladas_,
and _Zapus hudsonius americanus_ see accounts of those subspecies.

_Remarks._--Bole and Moulthrop (1942:165) refer 2 specimens from Elba,
New York, to _Z. h. hardyi_ (= _acadicus_); they are more nearly like
_Z. h. canadensis_ in size and shape of the auditory bullae and general
color of the pelage. A specimen from Spectacle Pond, New York, has the
narrow pterygoid fossae and relatively narrow auditory bullae of _Z. h.
acadicus_ and the relatively short, narrow incisive foramina, inflated
frontal region, and color of _Z. h. canadensis_ to which the specimen is
here referred. Intergradation is noted also in animals from Schreiber,
Ontario. They resemble _Zapus hudsonius hudsonius_ in their darker
coloration and shape of auditory bullae but in the remainder of the
characters studied resemble _Z. h. canadensis_ to which they are
referred. Specimens from Notre Dame de la Dore and 1/2 mi. N Mistassini
Post, Quebec, in size and shape of the auditory bullae and in width of
the pterygoid fossae, closely approach _Z. h. ladas_ but in color,
distinct dorsal band, and in narrower zygomata are all nearest _Z. h.
canadensis_ to which subspecies they are here referred.

_Zapus hudsonius ontarioensis_ Anderson (1942:59) from eastern Ontario
was based chiefly, in comparison with _Z. h. canadensis_, upon, "dorsal
stripe less distinct and sides somewhat duller yellowish with more
admixture of blackish hairs." Examination of 68 of the 69 specimens from
the type locality shows that 58 are subadult and in subadult pelage.
Individuals which are adult are indistinguishable in color of pelage and
in cranial features from comparable material from southern Quebec. _Z.
h. ontarioensis_ is, therefore, considered to be a synonym of _Z. h.
canadensis_.

_Specimens examined._--Total, 123, distributed as follows:

NEW YORK: _Franklin Co._: Spectacle Pond, Brighton Township, 2 (AMNH).
_Genesee Co._: Elba, 2 (Clev. MNH).

ONTARIO: Schreiber, 2 (NMC); Franz, 5 (MVZ); Pancake Bay, Algoma
District, 68 (NMC); Maclennan, Algoma District, 3 (ROM); Cache Lake,
Algonquin Park, 1 (MVZ); _Experimental Farm, Ottawa_, 1 (NMC); _Dows
Swamp, Ottawa_, 1 (NMC); Apple Hill, 1 (NMC); Clear Lake, Arden, 1
(NMC); _Athens_, 1 (NMC); _Aurora_, 4 (Clev. MNH); Pattageville,
Toronto, 1; _Lorne Park, Toronto_, 1 (NMC); _Credit_, 2 (NMC);
Pickering, 1 (MVZ); _Preston_, 1 (NMC); St. Thomas, 1 (NMC).

QUEBEC: _Notre Dame de la Dore_, 3 (NMC); 1/2 mi. N Mistassini Post, 1
(NMC); Lake Albanel, 1 (NMC); St. Felicien, 3 (NMC); Valcartier, 8
(NMC); Kiamika Lake, 4 (NMC); _Ste. Veronique_, 2 (NMC); _Val Jalbert_,
2 (NMC); _St. Methode_, 1 (NMC).

_Marginal records._--Quebec: 1/2 mi. N Mistassini Post; Valcartier. New
York: Spectacle Pond, Brighton Township; Elba. Ontario: St. Thomas;
Pancake Bay, Algoma Dist.; Franz; Schreiber. Quebec: Kiamika Lake.


=Zapus hudsonius hudsonius= (Zimmerman)

    _Dipus hudsonius_ Zimmerman, Geog. Geschichte d Menschen u.
        vierfussigen Thiere, 2:358, 1780.

    _Dipus labradorius_ Kerr, Animal Kingdom:276 (based on the Labrador
        Jerboid Rat of Pennant, 1781--but Preble, N. Amer. Fauna, 15:11,
        August 8, 1899, states that the specimen came from Hudson Bay),
        1792.

    _Gerbillus canadensis_, Desmarest, Mammalogie, 2:321, 1822.

    _Gerbillus labradorius_, Harlan, Fauna Amer., p. 157, 1825.

    _Meriones labradorius_, Richardson, Fauna Boreali-Americana, 1:144,
        1829.

    _Jaculus labradorius_ Wagner, Suppl. Schreber's Saugthiere, 3:294,
        1843.

    _Zapus hudsonius hudsonius_, Preble, N. Amer. Fauna, 15:15, August
        8, 1899 (part--the part from Northwest Territory, Ontario,
        Michigan, northern Wisconsin and northern Minnesota).

    _Zapus hudsonius alascensis_, Osgood, N. Amer. Fauna, 19:38,
        October 6, 1900.

_Type._--Type specimen not known to be in existence; from Hudson Bay,
locality now considered to be Fort Severn, Ontario (see Anderson,
1942:37).

_Range._--Central Alaska southeastward to central Ontario, northern
Minnesota, northern Wisconsin, and upper peninsula of Michigan. See fig.
47. Zonal range: Hudsonian, Canadian, and into Transition.

_Description._--Size medium; back dark, from near Tawny-Olive to near
Cinnamon with heavy admixture of black hair forming dorsal band; sides
lighter than back and from near Tawny-Olive to near Cinnamon, sometimes
with admixture of black hair giving sides streaked appearance; lateral
line usually distinct, clear Ochraceous-Buff; underparts white,
sometimes with slight suffusion of Ochraceous-Buff; tail bicolored,
brown to brownish-black above, grayish-white to yellowish-white below;
ears dark, usually edged with ochraceous; feet grayish-white above;
incisive foramina relatively short and broadly rounded; zygomata
relatively short; braincase relatively broad; auditory bullae flat,
long, and relatively broad; pterygoid fossae relatively narrow; nasals
relatively broad and short.

_Comparisons._--From _Zapus hudsonius alascensis_, _Z. h. hudsonius_
differs as follows: upper parts generally darker, more black tipped
hair; sides darker with greater suffusion of dark hair; lateral line
brighter, more distinct; size averaging smaller; zygomatic arches less
bowed outward; distance from incisors to postpalatal notch shorter;
zygomata shorter; occipitonasal length less; mastoid region narrower.

From _Zapus hudsonius intermedius_, _Z. h. hudsonius_ differs in: color
darker, more tawny dorsally; sides averaging darker, more black-tipped
hairs; size averaging larger; braincase averaging broader; distance from
incisors to postpalatal notch averaging slightly shorter; zygomata
averaging longer; mastoid region averaging broader; incisive foramina
averaging shorter.

From _Zapus hudsonius tenellus_, _Z. h. hudsonius_ differs as follows:
upper parts averaging darker; tail averaging shorter; condylobasal
length averaging more; braincase averaging broader; auditory bullae
broader and less inflated; interparietal averaging broader; incisive
foramina more broadly rounded and averaging longer.

For comparison with _Zapus hudsonius canadensis_ and _Zapus hudsonius
campestris_ see accounts of those subspecies.

_Remarks._--Preble (1899:16) had available for study five specimens of
_Zapus hudsonius hudsonius_ from Hudson Bay. Four were preserved in
alcohol and one as an incomplete skin (prepared from an alcoholic
specimen). All were unreliable for comparative purposes owing to the
effects of the preservative. Preble, therefore, (_loc. cit._) selected
as a fairly typical sample a series of specimens from Tower, St. Louis
County, Minnesota; these formed the basis of comparison between _Z. h.
hudsonius_ and other subspecies of _Zapus hudsonius_. Now that
additional material (well prepared skins and skulls) is available from
the Hudson Bay region and from other localities in northern and western
Canada it is evident that the specimens from Tower, although here
considered to be _Z. h. hudsonius_, are not typical _Z. h. hudsonius_
but are intergrades between _hudsonius_ and specimens of _Zapus
hudsonius intermedius_. Comparisons made in the present account are
based on specimens from the vicinity of Hudson Bay (Fort Severen,
Ontario, York Factory, Shamatawa River, and Robinson Portage, Manitoba).
These individuals are considered typical of this subspecies. With these
new data available the range of _Z. h. hudsonius_ is now understood to
include all of the region from eastern Alaska to the northern parts of
Minnesota, Wisconsin, and Michigan.

Intergradation between _Zapus hudsonius canadensis_ and _Z. h.
hudsonius_ is noted in specimens from 30 mi. NE Port Arthur and also in
those from Silver Islet, Thunder Cape, Ontario. These individuals
resemble _Z. h. canadensis_ in size and shape of the auditory bullae and
in the shape of the nasals, but in their darker coloration, broadly
rounded incisive foramina, and relatively narrow pterygoid fossae they
are more nearly like _Z. h. hudsonius_ to which they are here referred.

Specimens from Minaki, Ontario, are tending toward _Zapus hudsonius
intermedius_ in lighter coloration but in the size and shape of the
auditory bulla, size and shape of the incisive foramina, and in the
width of the pterygoid fossae they are more nearly like _Z. h.
hudsonius_ to which they are here referred. Specimens from various
localities in Menominee County, Michigan, are like _Z. h. intermedius_
in shape of the incisive foramina and shape of the postpalatal notch,
but in color of pelage, size and shape of the auditory bullae, and
breadth of the pterygoid fossae they closely resemble _Z. h. hudsonius_.

In Wisconsin, intergradation occurs in color and in cranial characters
in specimens from Mercer, Solon Spring, and in a single individual from
Basswood Lake. All these specimens, however, are best referable to _Z.
h. hudsonius_.

Specimens from one mile southwest of Fairbanks and from Fairbanks,
Alaska, show intergradation with _Zapus hudsonius alascensis_ in
coloration (more brown, less black), but in small size, short, broadly
rounded incisive foramina, and in size and shape of the auditory bullae
are nearest to _Z. h. hudsonius_ to which they are here assigned.

Intergradation with _Zapus hudsonius alascensis_ is noted also in
specimens from McIntyre Creek, Yukon. They are like _Z. h. alascensis_
in the size and shape of the auditory bullae and in the more elongate
incisive foramina, but in the coloration, size of the pterygoid fossae,
and breadth of the braincase are more nearly like _Z. h. hudsonius_ and
are here referred to this geographic race.

In British Columbia, in specimens from 1 mi. NW junction of Irons Creek
and Laird River as well as in those from Hot Springs, 3 mi. WNW junction
of Trout River and Laird River, and in those from 1/4 mi. S of the
junction of the same rivers, three way intergradation occurs. These
animals are like _Zapus hudsonius alascensis_ in color and in length of
tail. They agree with _Zapus hudsonius tenellus_ in shape of nasals. In
degree of inflation of auditory bullae, in length and width of incisive
foramina, and in shape of pterygoid fossae they are as in _Z. h.
hudsonius_ to which they are here assigned.

_Specimens examined._--Total, 230, distributed as follows:

ALASKA: Fairbanks, 1 (USNM); _1 mi. SW Fairbanks, 440 ft._, 1.

ALBERTA: Conibear Lake, Wood Buffalo Park, 1 (NMC); Assineau River, 1920
ft., 10 mi. E and 1 mi. N Kinuso, 1; Mountain Rapid, Athabasca River, 1
(USBS); _Brule Rapid, Athabasca River_, 1 (USBS); _25 mi. above Pelican
Rapid, Athabasca River_, 1 (USBS); Lac la Nonne, 7 (NMC); _Swift
Current, Athabasca River_, 1 (USBS); _junction Lac la Biche River and
Athabasca River_, 1 (USBS); 30 mi. above Athabasca Landing, Athabasca
River, 1 (USBS).

BRITISH COLUMBIA: 1 mi. NW junction Irons Creek and Laird River, 3; Hot
Springs, 3 mi. WNW junction Trout River and Laird River, 1; _1/4 mi. S
junction Trout River and Laird River_, 1.

MANITOBA: York Factory, 2 (USBS); Shamatawa River, 1 (USBS); Oxford
House, 15 (USBS); _Robinson Portage_, 4 (USBS); _Echamamish_, 1 (USBS);
Norway House, 1 (USBS); _Swan River_, 1 (NMC); Bird, 1 (NMC); _Aimie
Lake_, 2 (NMC); Albert's Lake, Flin Flon, 2 (NMC); Portage La Prairie
Prov., Delta, 1 (UM).

MACKENZIE DISTRICT: Fort Resolution, 3 (USBS); Fort Smith, 3 (USBS).

MICHIGAN: _Chippewa Co._: Marquette Nat'l Forest, 4; _no exact
locality_, 2. _Gogebic Co._: Mud Lake, 1/4 mi. SE Thousand Island Lake,
2. _Keweenaw Co._: Lake Manganese, 1 mi. SSE Copper Harbor, 5 (UM);
_2-1/5 mi. SE Copper Harbor_, 8 (UM); _5 mi. E Eagle Harbor_, 6 (UM); _E
end Lake Upson_, 3 (UM); _Bete Grise_, 5 (UM). _Marquette County_:
Michigamme, 3 (2 USBS). _Menominee Co._: _8 mi. N Hermansville_, 6 (UM);
_6 mi. NW Banat_, 8 (UM); _5 mi. SW Banat_, 8 (UM); _8 mi. SW Banat_, 2
(UM); _7 mi. E Stephenson_, 3 (UM); _8 mi. WSW Stephenson_, 2 (UM); _10
mi. W Stephenson_, 2 (UM); _13 mi. WSW Stephenson_, 2 (UM); 5 mi. N
Menominee, 2 (UM).

MINNESOTA: _Lake Co._: Splitrock River, 2 (UM); _St. Louis County_:
Tower, 27 (USBS).

ONTARIO: Fort Severn, Kenora District, 6 (ROM); Minaki, 7 (MVZ); _30 mi.
NE Port Arthur_, 6 (UM); Silver Islet, Thunder Bay District, 4 (NMC);
_20 mi. SW Fort Williams_, 3 (UM); _20 mi. SE Fort Williams_, 1 (UM).

SASKATCHEWAN: Emma Lake, 3 (ROM).

WISCONSIN: _Bayfield County_: _Herbster_, 4 (USBS); Brinks Camp,
Washburn, 1 (AMNH); _Basswood Lake, 10 mi. SE Iron River_, 1 (USBS).
_Douglas County_: Solon Springs, 9 (USBS). _Forest County_: Crandon, 1
(USBS). _Iron County_: Mercer, 2 (USBS). _Oneida County_: _Crescent
Lake_, 2 (USBS). _Vilas County_: _Mamie Lake_, 2 (USBS); _Lake St.
Germain_, 9 (USBS).

YUKON: Lake Lebarge, 3 (USBS); Forks of MacMillian River, 1 (USBS);
McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 4.

_Marginal records._--Alaska: Fairbanks. MacKenzie: Ft. Resolution.
Manitoba: York Factory. Ontario: Fort Severn, Kenora District; Silver
Islet, Thunder Bay Dist. Michigan: Marquette Nat'l Forest; 5 mi. N
Menominee. Wisconsin: Crandon; Solon Springs. Minnesota: Tower.
Manitoba: Portage la Prairie Prov., Delta. Saskatchewan: Emma Lake.
Alberta: 30 mi. above Athabasca Landing, Athabasca River; Lac la Nonne.
British Columbia: 1 mi. NW junction Irons Creek and Laird River. Yukon:
McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse; Lake Lebarge.


=Zapus hudsonius intermedius= new subspecies

_Type._--Male, adult, No. 83400, Univ. Michigan Mus. Zool.; Ridgeway,
Winneshiek County, Iowa; obtained on July 22, 1939, by S. A. Hoslett,
original No. 517.

_Range._--Eastern Montana, North Dakota, probably northern South Dakota,
all but northern parts of Minnesota and Wisconsin, Iowa, Illinois,
southwestern Indiana, and western Kentucky. See fig. 47. Zonal range:
Upper Austral (Upper Sonoran and Carolinian) and Transition (Alleghanian
and Transition).

_Description._--Size medium; back from near Warm Buff to near
Ochraceous-Buff with admixture of hair tipped with black or dark brown
usually forming distinct, broad, dorsal band; sides lighter, from near
Warm Buff to near Ochraceous-Buff with sparse mixture of dark-tipped
hairs; lateral line often poorly marked but when present of clear
Ochraceous-Buff; belly white, sometimes with slight suffusion of color
of sides; tail bicolored, grayish-brown to brownish-black above, white
to grayish-white or yellowish-white below; ears dark, narrowly edged
with color of sides; feet white to grayish-white above; tail relatively
short; lateral margins of nasals parallel; auditory bullae relatively
short, broadly rounded, and moderately inflated; incisive foramina
relatively long and narrow; pterygoid fossae relatively narrow; zygomata
relatively long; inferior ramus of zygomatic process of maxillary
frequently lacking a median projection.

_Comparisons._--From _Zapus hudsonius pallidus_, _Z. h. intermedius_
differs as follows: Coloration duller, not so bright, more yellow or
buff and less bright Ochraceous-Buff; interorbital region averaging
narrower; incisive foramina averaging longer and narrower; condylobasal
length averaging greater; braincase averaging broader; mastoid region
averaging broader.

For comparisons with _Zapus hudsonius hudsonius_, _Zapus hudsonius
campestris_, and _Zapus hudsonius americanus_ see accounts of those
subspecies.

_Remarks._--_Zapus hudsonius intermedius_ has a large geographic range.
There is some variation detectable when individuals from widely separate
localities are compared, but where there is much variation it is
obviously the result of intergradation. All characters differentiating
_Z. h. intermedius_ from any contiguous subspecies are not present in
every specimen even in the type series. Nevertheless, a certain series
of cranial characters (narrow incisive foramina, short rounded auditory
bullae, parallel lateral margins of nasals and narrow pterygoid fossae)
is diagnostic.

Animals obtained from extreme southwestern Indiana and from eastern
Illinois approach _Z. h. americanus_ in color and in shape of the
incisive foramina, but in the shape of the nasals, width of the
pterygoid fossae and breadth of the zygomata are most nearly like _Z. h.
intermedius_ to which they are here referred. Specimens from Lake and
Kane counties, Illinois, also show affinity with _Z. h. americanus_ in
color, but cranially are most nearly like _Z. h. intermedius_ and are
assigned to that subspecies.

Two specimens from southern Illinois (Perry County) are intergrades
between _Z. h. pallidus_ and _Z. h. intermedius_. Cockrum and Baker
(1950:3) mentioned that these individuals showed evidence of
intergradation with _Z. h. pallidus_ in color of the pelage and the
breadth of the least interorbital constriction. In other characters the
specimens are most nearly like _Z. h. intermedius_ to which they are
here referred. Animals from Lyon County, Iowa, also show intergradation
between _Z. h. pallidus_ and _Z. h. intermedius_. These individuals are
most nearly like _Z. h. pallidus_ in interorbital breadth of the skull
but in other characters agree with _Z. h. intermedius_ and, therefore,
are referred to that subspecies.

Intergradation between _Z. h. campestris_ and _Z. h. intermedius_ is
noted in a specimen from 7 mi. NE Glendive, Montana. This individual has
the larger, broader, auditory bullae and more widely bowed incisive
foramina of _Z. h. campestris_, but in color, in smaller external size,
and in the majority of cranial characters it is best referred to _Z. h.
intermedius_.

Specimens from the north-central periphery of the geographic range of
_Z. h. intermedius_ (northern Minnesota and Wisconsin) on the average
are darker, have longer auditory bullae, wider bowed incisive foramina,
and (some specimens) a slightly wider pterygoid fossa than is normal in
more southern populations. This deviation from the norm is interpreted
as intergradation between _Z. h. hudsonius_ and _Z. h. intermedius_.
Individuals from Burnett, Price, and Oconto counties, Wisconsin, and
those from Cass and southern Clearwater counties, Minnesota, show such
intergradation but are here considered to be _Z. h. intermedius_.

_Specimens examined._--Total, 199, distributed as follows:

ILLINOIS: _Coles Co._: Fox Ridge State Park, 1 (UIM). _Fulton Co._: _1/2
mi. N Norris_, 2 (UIM); _3 mi. N Canton_, 1 (UIM); _2-1/2 mi. N Canton_,
2 (UIM); _2 mi. NW Canton_, 3 (UIM); 2 mi. W Canton, 1 (UIM); _3 mi. SW
Monterey_, 1 (UIM). _Jo Daviess Co._: _near Galen_, 3 (FM). _Kane Co._:
Sugar Grove, 1 (Chic. AS). _Lake Co._: Fox Lake, 4 (FM); _Pistake Bay_,
1 (FM). _Perry Co._: 6 mi. S Pinckneyville (near Pyatt), 2 (SITC).
_Vermilion Co._: _Kickapoo State Park_, 2 (UIM); Jordan Creek, 3 mi. NE
Fairmont, 5 (UIM).

INDIANA: _Owen Co._: La Fayette, 1 (USNM). _Parks Co._: Turkey Run State
Park, 2 (1 UM; 1 UIM). _Posey Co._: Hovey Lake, 1 (UM); New Harmony, 2
(Clev. MNH); no exact locality, 2 (UM). _Sullivan Co._: no exact
locality, 1 (UM).

IOWA: _Dickinson Co._: _Camp Forester, E Okeboji Lake_, 3 (ISC). _Emmet
Co._: Fort Defiance State Park, 1 (ISC). _Hamilton Co._: _Little Wall
Lake, Jewell_, 6 (ISC). _Ida Co._: Arthur, 1 (ISC). _Lyon Co._: Elgin
Township, Sec. 35, 2 (ISC); _Riverside Township, Sec. 28_, 1 (ISC).
_Palo Alto Co._: _Ruthven_, 1 (ISC). _Sioux Co._: Ireton, 1 (UM). _Story
Co._: Ames, 1 (ISC). _Winneshiek Co._: Decorah, 3 (UM); _Ridgeway_, 11
(UM); Conover, 3 (UM).

KENTUCKY: _Lyon Co._: no exact locality, 1 (USNM).

MONTANA: _Dawson Co._: Yellowstone River, 7 mi. NE Glendive, 2000 ft., 1
(MVZ).

MINNESOTA: _Cass County_: _Cass Lake_, 7 (USBS). _Clearwater Co._:
Itasca Park, Biological Station, 5 (UM). _Grant Co._: 3 mi. NW Barrett,
1 (UM). _Jackson Co._: 4 mi. E Heron Lake, 1 (UM). _Ottertail Co._: _5
mi. NW Vergas_, 8 (UM); _4 mi. NW Ashley, 1430 ft._, 2. _Ramsey Co._:
St. Paul, 1 (UM). _Sherburne County_: Elk River, 23 (2 UM; 6 MVZ; 3
USBS). _Winona County_: La Crescent, 3 (USBS).

NORTH DAKOTA: _Cass County_: Fargo, 1 (USBS). _Dickey County_: _Ludden_,
1 (USBS); Ellendale, 1 (USBS). _Kidder County_: _Pettibone_, 3 (Chic.
AS). _La Moure County_: _La Moure_, 1 (USBS). _Oliver County_: Fort
Clark, 3 (USBS). _Pembina County_: Pembina, 2 (USNM). _Ramsey County_:
Devils Lake, 3 (USBS). _Ramson County_: _Lisbon_, 1 (USBS). _Richland
County_: _Wahpeton_, 2 (USBS); _5 mi. NE Fairmont, Sioux River_, 5
(USBS); Blackner, 2 (USBS). _Rolette County_: Fish Lake, 2 (USBS).
_Sioux County_: Cannon Ball, 4 (USBS). _Williams Co._: Grinnell, 2
(USBS).

WISCONSIN: _Burnett County_: Danbury, 1 (USBS). _Chippewa County_:
_Holcombe_, 3 (USBS). _Clark County_: _Withee_, 4 (USBS); _Worden
Township_, 2 (USBS). _Crawford County_: Lynxville, 1 (USBS). _Dane Co._:
_Madison_, 2 (OHIO). _Dodge Co._: _Horicorn Refuge_, 2 (USBS). _Juneau
County_: _Mather_, 1 (USBS). _Marathon Co._: _Rib Hill_, 8 (USBS).
_Oconto County_: Lakewood, 1 (USBS). _Portage County_: Stevens Point, 3
(USBS). _Price County_: Ogema, 2 (USBS). _Rock County_: Milton, 1
(USBS). _Sauk County_: _Devils Lake_, 1 (USBS). _Sheboygan County_: 8
mi. SW Mellen, 1 (USBS); _Elkhart Lake_, 1 (USBS). _Walworth County_:
_Delavan, Fosters Bridge_, 1 (USBS); _Turtle Lake_, 1 (USBS). _Wood
Co._: _Thorp Township_, 2 (AMNH); _Hewett Township_, 4 (AMNH).

_Marginal records._--North Dakota: Fish Lake; Pembina. Wisconsin:
Danbury; Ogema; Lakewood. Illinois: Fox Lake. Indiana: La Fayette; New
Harmony. Illinois: 6 mi. S Pinckneyville (near Pyatt). Iowa: Ames;
Arthur; Ireton. Montana: Yellowstone River, 7 mi. NE Glendive, 2000 ft.
North Dakota: Grinnell.


=Zapus hudsonius ladas= Bangs

    _Zapus hudsonius ladas_ Bangs, Proc. New England Zool. Club, 1:10,
        February 28, 1899.

_Type._--Female, adult, skin and skull, No. 4169, E. A. and O. Bangs
Coll. (now in Mus. Comp. Zool.); Rigoulette, Hamilton Inlet, Labrador;
obtained on July 18, 1895, by C. H. Goldthwaite.

_Range._--Eastern Quebec north of Gulf of St. Lawrence, Labrador, and
Newfoundland. See fig. 47. Zonal range: Canadian and Hudsonian.

_Description._--Size medium; back relatively dark, near Ochraceous-Tawny
with admixture of black-tipped hair; dorsal band relatively wide but not
sharply defined against color of sides; side lighter than back, from
near Ochraceous-Tawny to near Cinnamon and lined with black-tipped hair;
lateral line distinct of clear Cinnamon-Buff or Light Ochraceous-Buff;
underparts white, often suffused with Ochraceous-Buff; tail distinctly
bicolored, dark brown to black above and yellowish-white to
grayish-white below; ears dark, usually flecked with Tawny Ochraceous
and edged with ochraceous; feet grayish-white above; incisive foramina
relatively short and broad; pterygoid fossae relatively broad; auditory
bullae broad and well inflated; mastoid region relatively broad;
zygomata relatively short; inferior arm of zygomatic process of
maxillary relatively broad.

_Comparison._--From _Zapus hudsonius acadicus_, which _Z. h. ladas_
closely resembles, it differs in: Color darker, dorsal band much less
distinct, underparts more frequently suffused with Ochraceous-Buff;
auditory bullae relatively broader and more inflated; pterygoid fossae
broader; zygomata averaging shorter; incisive foramina relatively
shorter; inferior arm of zygomatic process of maxillary relatively
broader.

From _Zapus hudsonius canadensis_, _Z. h. ladas_ differs as follows:
Color darker, more richly tawny, dorsal band less distinct; auditory
bullae relatively shorter, more inflated; pterygoid fossae averaging
broader; zygomata averaging broader; incisive foramina averaging longer.

_Remarks._--This subspecies retains all of its diagnostic characters
throughout nearly all parts of its geographic range. Specimens from Nova
Scotia are like _Z. h. ladas_ in their darker color and less distinct
dorsal band, but in the remainder of their characters they are distinct
and best referable to _Z. h. acadicus_.

_Zapus h. ladas_, with its relatively large size, poorly defined dorsal
band, and broad, well inflated auditory bullae, is one of the better
marked subspecies of the species _Zapus hudsonius_.

_Specimens examined._--Total, 41, distributed as follows:

LABRADOR: Mahkovik, 1 (USNM); Etagaulet Bay, Lake Melvikl, 2 (USNM); 3
mi. above mouth of Naskaupi River, 1 (USNM); _Northwest River_, 6,
(USNM); Cartwright, 1 (USBS); Muskrat Falls, Hamilton River, 1 (USNM);
Hamilton River, Flour Lake, 3 (USNM); Hawke Harbor, 4 (USNM); Goose Bay,
3 (USNM); _Niger Sound, Islet Bay_, 1 (USNM); Red Bay, 5 (USNM);
_Mecklenburg Harbor_, 2 (USNM); _Mary Harbor_, 1 (USNM).

NEWFOUNDLAND: Hare Harbor, 3 (USNM).

_Quebec_: northwest Ungava, 1 (NMC); Moise Bay, 5 (NMC); Trout Lake,
near Moise Bay, 1 (NMC).

_Marginal records._--Labrador: Mahkovik; Red Bay. Newfoundland: Hare
Harbor. Quebec: Trout Lake, near Moise Bay; northwest Ungava.


=Zapus hudsonius pallidus= Cockrum and Baker

    _Zapus hudsonius pallidus_ Cockrum and Baker, Proc. Biol. Soc.
        Washington, 63:1, April 26, 1950.

    _Jaculus hudsonius_, Baird, Repts. Expl. and Surv. 111, 8
        (pt. 1):433, July 14, 1858 (part--the part from Platte River,
        Nebraska, and Cass County, Missouri).

    _Zapus hudsonius_, Coues, Bull. U. S. Geol. and Geog. Surv. of the
        Territories, 2nd ser. No. 5:260, 1877 (part--the part from Platte
        River, Nebraska).

    _Zapus hudsonius campestris_ Preble, N. Amer. Fauna, 15:20, August
        8, 1899 (part--the part from Columbus in Nebraska and Jackson
        County in Missouri).

_Type._--Male, adult, No. 22953, Univ. Kansas Mus. Nat. Hist.; NW corner
sec. 4, T. 12S, R. 20E, 5-1/2 mi. N, 1-3/4 mi. E Lawrence, Douglas
County, Kansas; obtained on May 4, 1948, by E. Lendell Cockrum and
Rollin H. Baker, original No. 916 of Cockrum.

_Range._--Southern South Dakota, Nebraska, Kansas, Missouri, and
northeastern Oklahoma. See fig. 47. Zonal range: Upper Austral (Upper
Sonoran and Carolinian).

_Description._--Size small; back near Cinnamon-Buff with admixture of
dark-tipped hair forming distinct, broad, dorsal band; sides bright
Cinnamon-Buff with sparse mixture of dark-tipped hair; lateral line
usually distinct, of clear Cinnamon-Buff; belly white, sometimes with
suffusion of color of sides, tail bicolored, brownish to brownish-black
above, grayish-white to yellowish-white below; ears dark, narrowly edged
with color of sides; feet white to grayish-white above; mastoid region
relatively narrow; maxillary tooth-row relatively short; zygomata
relatively short; zygomatic arch relatively broad; interorbital region
relatively broad; auditory bullae relatively small and narrow; lateral
margins of nasals not constricted posteriorly.

_Comparisons._--From _Zapus hudsonius preblei_, _Z. h. pallidus_ differs
as follows: Coloration brighter and richer, more buff, less black;
zygomatic arch more broadly bowed; condylobasal length averaging less;
braincase narrower; interorbital region broader; incisive foramina
shorter.

For comparisons with _Zapus hudsonius pallidus_ and _Zapus hudsonius
intermedius_ see accounts of those subspecies.

_Remarks._--The characters that distinguish this jumping mouse from
neighboring kinds are relatively stable throughout most of its
geographic range. _Zapus hudsonius pallidus_ is one of the best defined
subspecies of _Z. hudsonius_.

One specimen from Batesland, South Dakota, is referred to _Z. h.
pallidus_ but shows evidence of intergradation with _Zapus hudsonius
campestris_ in the shape of the nasals, incisive foramina, and in
breadth of the zygomatic arch. An animal from 3 mi. NE Ponca, Nebraska,
is intermediate between _Z. h. pallidus_ and _Zapus hudsonius
intermedius_ in size and shape of the auditory bullae and in the breadth
of the pterygoid fossae, but since this individual shows more
resemblance to _Z. h. pallidus_ in coloration and in the majority of
cranial characters it is here referred to _Z. h. pallidus_. Specimens
from Beemer, Nebraska, show an intergrading tendency toward _Zapus
hudsonius intermedius_ in the reduced lateral bowing of the zygomatic
arch and in shorter zygomata. Since these individuals resemble _Z. h.
pallidus_ in the majority of characters they are referred to that race.
An individual of _Z. h. pallidus_ from Pevely, Missouri, is to some
extent an intergrade with _Z. h. intermedius_ of neighboring southern
Illinois. Two individuals of _Z. h. pallidus_ from Mohawk Park,
Oklahoma, are darker dorsally than, but otherwise similar to, specimens
from the type locality.

_Zapus hudsonius pallidus_ seems to be the terminus of a cline; this is
a southward trend toward smaller size and lighter, brighter color. There
is a similar clinal tendency in the jumping mice in eastern North
America, and _Z. h. americanus_ from North Carolina, pronouncedly
resembles _Z. h. pallidus_ from Kansas.

_Specimens examined._--Total, 44, distributed as follows:

KANSAS: _Brown Co._: Horton, 1. _Douglas Co._: Sec. 8, T. 123, R. 20E,
5-1/2 mi. N, 1-3/4 mi. E Lawrence, 10; _5 mi. N and 1-1/2 mi. E
Lawrence_, 3; _Robinson Farm, 5 mi. N and 3 mi. E Lawrence_, 2; _4 mi.
N, 2-1/2 mi. E Lawrence_, 1; Lakeview, 2; _7-1/2 mi. SW Lawrence_, 1.
_Greenwood Co._: 1/2 mi. S Hamilton, 1.

MISSOURI: _Cole Co._: Jefferson City, 2 (MO). _Jackson Co._: _no exact
locality_, 1 (USBS). _Jefferson County_: Pevely, 1 (USBS).

NEBRASKA: _Blaine Co._: _Dismal River, at Thomas-Blaine County line_, 1
(NGFP). _Boyd Co._: 2 mi. E and 15 mi. S Spencer, 1. _Buffalo Co._:
Platte Meadows, Kearney, 1 (HM). _Butler Co._: 5 mi E Rising City, 1.
_Cherry Co._: Niobrara River, 18 mi. NW Kennedy, 1; Ballard Marsh, 20
mi. S Valentine, 1 (JKJ); _Pony Lake Headquarters, Valentine Nat'l
Wildlife Refuge_, 1 (JKJ). _Colfax Co._: _2 mi. S Schuyler_, 1 (JKJ).
_Cuming County_: Beemer, 4 (USBS). _Dixon Co._: 3 mi. NE Ponca, 1.
_Platte County_: _Columbus_, 1 (USBS). _Richardson Co._: 5 mi. SE Rulo,
1 (NGFP).

OKLAHOMA: _Tulsa Co._: Mohawk Park, 2 (UM).

SOUTH DAKOTA: _Bennett Co._: Batesland, 1 (FM).

_Marginal records._--South Dakota: Batesland. Nebraska: 3 mi. NE Ponca;
Beemer; 5 mi. SE Rulo. Missouri: Pevely. Oklahoma: Mohawk Park. Kansas:
1/2 mi. S Hamilton. Nebraska: Platte Meadows, Kearney; Ballard Marsh, 20
mi. S Valentine; Niobrara River, 18 mi. NW Kennedy.


=Zapus hudsonius preblei= new subspecies

_Type._--Male, adult, No. 73085, U. S. Nat. Mus., Biol. Surv. Coll.;
Loveland, Larimer County, Colorado; obtained on July 23, 1895, by E. A.
Preble, original No. 435.

_Range._--Southeastern Wyoming and north-central Colorado. See fig. 47.
Zonal range: Transition.

_Description._--Size medium; color dull, back from near Clay Color to
near Tawny-Olive with admixture of black hair forming poorly defined
dorsal band; sides lighter than back from near Clay Color to near
Cinnamon-Buff; lateral line distinct and clear Ochraceous-Buff; belly
white, sometimes with faint wash of clear Ochraceous-Buff; tail
bicolored, brownish to light brownish-black above, grayish-white to
yellowish-white below; ears dark, narrowly edged with color of sides;
feet grayish-white above; incisive foramina relatively narrow and
elongate; auditory bullae moderately inflated; pterygoid fossae
relatively broad; postpalatal notch broadly rounded; interorbital region
relatively narrow; zygomatic arch not widely bowed; frontal region well
inflated; distance from incisors to postpalatal notch relatively short.

_Comparisons._--Among named subspecies, _Zapus hudsonius preblei_ most
closely resembles _Z. h. campestris_. From topotypes of _Z. h.
campestris_, _Z. h. preblei_ differs as follows: Upper parts generally
dull, averaging lighter, less black-tipped hair; dorsal band less
distinct; sides duller; averaging smaller in most cranial measurements
taken; least interorbital constriction narrower; auditory bullae
smaller, less well inflated; incisive foramina narrower, not truncate
posteriorly; frontal region usually more inflated.

From _Zapus hudsonius pallidus_, _Z. h. preblei_ differs as follows:
Upper parts generally duller (less ochraceous); dorsal band less
distinct; sides paler (not bright Ochraceous-Buff); zygomatic arch less
widely bowed; least interorbital constriction narrower; occipitonasal
length averaging greater; distance from incisors to postpalatal notch
averaging less; incisive foramina longer, proportionally less widely
bowed; auditory bullae longer; pterygoid fossae averaging broader.

_Remarks._--No evidence of intergradation with any other geographic race
was noted. To the east the range of _Z. h. preblei_ is separated from
that of _Z. h. pallidus_ (western Kansas and southwestern Nebraska), by
several hundred miles of mixed and short grass prairie. Much of this
area is unsuitable to jumping mice but local marshy places might be
inhabited. Much territory inhospitable to _Zapus_ intervenes also
between the ranges of _Z. h. preblei_ and _Z. h. campestris_. This area
(northern Platte, Goshen, eastern Converse, Niobrara, and southern
Weston counties, Wyoming) is chiefly rolling hills and short grass
prairie and, like that to the east, is only locally suitable for
_Zapus_. If jumping mice do occur in suitable places in these
intervening areas it is to be expected that they will show
intergradation between the subspecies concerned.

_Zapus hudsonius preblei_, on the basis of 11 specimens, agrees most
closely in size and color with _Z. h. campestris_; there is much less
resemblance between _Z. h. preblei_ and _Z. h. pallidus_.

An adult from Springhill, 12 mi. N Laramie Peak, is typically _Z. h.
preblei_ as is one from Cheyenne.

Although specimens of _Z. h. preblei_ are few (4 adult, 7 non-adults),
the differences between this and neighboring named kinds is
considerable.

_Specimens examined_: Total, 11, distributed as follows:

COLORADO: _Boulder County_: 3 mi. E Boulder, 1 (UCM); _5 mi. E Boulder_,
1 (UCM); _south of Boulder_ (no exact locality), 1 (UCM). _Jefferson
County_: Semper, 1. _Larimer County_: Loveland, 2 (USBS).

WYOMING: _Albany County_: Springhill, 12 mi. N Laramie Peak, 6300 ft., 3
(USBS). _Laramie County_: Cheyenne, 1 (USNM). _Platte County_:
Chugwater, 1 (Clev. MNH).

_Marginal records._--Wyoming: Springhill, 12 mi. N Laramie Peak, 6300
ft.; Chugwater; Cheyenne. Colorado: Loveland; Semper.


=Zapus hudsonius tenellus= Merriam

    _Zapus tenellus_ Merriam, Proc. Biol. Soc. Washington, 11:103,
        April 26, 1897.

    _Zapus hudsonius tenellus_, Hall, Univ. California Publ. Zool.,
        40:377, November 5, 1934.

    _Zapus hudsonius hudsonius_, Baker, Univ. Kansas Publ., Mus. Nat.
        Hist., 5:111, November 28, 1951 (part--the part from E side
        Minaker River, 1 mi. W Trutch and 3 mi. N Fort St. John,
        British Columbia).

_Type._--Female, young adult, skin and skull, No. 66932 U. S. Nat. Mus.,
Biol. Surv. Coll.; Kamloops, British Columbia; obtained on August 25,
1894, by Clark P. Streator, original No. 4196.

_Range._--British Columbia. See fig. 47. Zonal range: Canadian and
Hudsonian.

_Description._--Size medium; back from near Clay Color (brighter) to
near Cinnamon-Buff with admixture of black tipped hairs forming a weakly
defined dorsal band; sides lighter than back from near dull
Ochraceous-Buff to near Cinnamon-Buff frequently with admixture of
dark-tipped hairs; lateral line usually distinct, of clear
Ochraceous-Buff; belly white sometimes with slight suffusion of
Ochraceous-Buff; tail bicolored, brownish to brownish-black above, white
or grayish-white to yellowish-white below; ears dark, edged and flecked
on inner surface with color of sides; feet grayish-white above; auditory
bullae relatively narrow, moderately inflated, elongate when viewed from
below, anterior edge slightly concave; incisive foramina relatively
short; braincase relatively narrow; vertical depth of skull at junction
of frontals and nasals relatively great; nasals relatively narrow;
pterygoid fossae moderately broad; zygomata relatively short.

_Comparisons._--For comparisons with _Zapus hudsonius hudsonius_ and
_Zapus hudsonius alascensis_ see accounts of those subspecies.

_Remarks._--Merriam (1897a:103) named this jumping mouse as a full
species, mentioning that the skull is similar in size and characters to
that of _Zapus hudsonius_ but that externally these animals differed in
coloration and length of the tail. Hall (1934:377) treated _Z. tenellus_
as a subspecies of _Z. hudsonius_. He observed that the difference
between _Z. tenellus_, _Z. h. alascensis_, and _Z. h. hudsonius_ was of
the same degree, and, even though intergrading material was not known to
him, he considered _tenellus_ only subspecifically distinct from _Z.
hudsonius_. Hall (_loc. cit._) tentatively referred to _Z. h. tenellus_
specimens from Indianpoint Lake, 15 mi. NE Barkerville, Cottonwood P.
O., and Hazelton, British Columbia. I have seen and compared with the
type of _Z. tenellus_ all specimens examined by Hall and agree with him
that they are best referred to _Z. h. tenellus_. Since 1934, several
additional localities in British Columbia have yielded specimens. Those
from Minaker River and Fort St. John are intermediate in dorsal
coloration and in size and shape of the auditory bullae between _Zapus
hudsonius hudsonius_ and _Z. h. tenellus_ but in all other characters
are most nearly like _Z. h. tenellus_ to which they are here assigned.
These intergrades constitute additional evidence that _Z. tenellus_ and
_Z. hudsonius_ are only subspecies of a single species.

_Specimens examined._--Total, 17, all from British Columbia, distributed
as follows: east side Minaker River, 1 mi. W Trutch, 1; Hazelton, 959
ft., 2 (MVZ); 5 mi. W and 3 mi. N Fort St. John, 1; _Indianpoint Lake,
15 mi. NE Barkerville_, 5 (MVZ); Cottonwood P. O., 3 (MVZ); S end Swan
Lake, Vernon, 1200 ft., 2 (MVZ); Kamloops, 3 (USBS).

_Marginal records._--British Columbia.--E side Minaker River, 1 mi. W
Trutch; 5 mi. W and 3 mi. N Fort St. John; S end Swan Lake, Vernon, 1200
ft.; Kamloops; Hazelton, 959 ft.

    TABLE 5.--Cranial Measurements (in Millimeters) of Zapus.

  Column headings:

  Col. A: Number examined, [M][M] plus [F][F]
  Col. B: Breadth of braincase
  Col. C: Condylobasal length
  Col. D: Interorbital breadth
  Col. E: Mastoidal breadth
  Col. F: Length of maxillary tooth-row
  Col. G: Occipitonasal length
  Col. H: Palatal length
  Col. I: Zygomatic breadth
  Col. J: Zygomatic length

  ========+======+======+======+======+======+======+======+======+======
     A    |  B   |  C   |  D   |  E   |  F   |  G   |  H   |  I   |  J
  --------+------+------+------+------+------+------+------+------+------
          |
          |  _Zapus trinotatus eureka_, Big Lagoon, California.
          |
  13 mean | 10.3 | 21.4 |  4.2 | 10.9 |  3.9 | 24.5 | 10.4 | 12.5 |  9.5
     max  | 10.6 | 22.1 |  4.4 | 11.1 |  4.0 | 25.5 | 11.5 | 13.2 | 10.0
     min  | 10.0 | 20.7 |  3.9 | 10.0 |  3.7 | 24.0 | 10.5 | 12.1 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus trinotatus montanus_, Crater Lake, Oregon.
          |
  10 mean | 10.3 | 20.7 |  4.5 | 10.6 |  4.0 | 24.3 | 10.5 | 12.1 |  9.5
     max  | 10.5 | 21.5 |  4.7 | 11.1 |  4.1 | 24.8 | 10.8 | 12.6 |  9.8
     min  | 10.2 | 20.3 |  4.2 | 10.2 |  3.7 | 23.5 | 10.1 | 11.8 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Lost Cr. R. S., 10 mi. SE McKenzie Bridge, Oregon.
          |
  5 mean  | 10.3 | 20.9 |  4.5 | 10.7 |  3.9 | 24.2 | 10.4 | 12.1 |  9.3
    max   | 10.5 | 21.3 |  4.6 | 10.9 |  4.1 | 24.6 | 10.7 | 12.2 |  9.4
    min   | 10.2 | 20.4 |  4.4 | 10.5 |  3.8 | 23.5 | 10.0 | 12.0 |  9.1
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus trinotatus orarius_,
          |  3 mi. W Inverness, 800 ft., California.
          |
  12 mean |  9.9 | 20.4 |  3.8 | 10.8 |  3.7 | 22.6 | 10.0 | 12.1 |  9.3
     max  | 10.2 | 20.9 |  4.1 | 11.0 |  3.8 | 23.5 | 10.6 | 12.5 |  9.8
     min  |  9.6 | 19.9 |  3.7 | 10.4 |  3.6 | 21.7 |  9.8 | 11.9 |  8.5
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus trinotatus trinotatus_,
          |  Old Fort Clatsop, 100 ft., Oregon.
          |
  8 mean  | 10.3 | 21.1 |  4.4 | 10.7 |  3.8 | 24.3 | 10.6 | 12.3 |  9.6
    max   | 10.6 | 21.8 |  4.8 | 11.0 |  3.9 | 25.0 | 11.0 | 12.7 | 10.2
    min   | 10.0 | 20.2 |  4.0 | 10.4 |  3.7 | 23.6 | 10.0 | 11.9 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  Cayuse Meadow, 3800 ft., 3-1/2 mi. SW Steamboat Mt'n, Wash.
          |
  10 mean | 10.4 | 21.5 |  4.5 | 11.1 |  3.9 | 24.6 | 10.7 | 12.6 |  9.7
     max  | 10.6 | 22.2 |  4.8 | 11.4 |  4.1 | 25.4 | 11.1 | 12.8 | 10.0
     min  | 10.2 | 20.6 |  3.8 | 10.8 |  3.8 | 23.7 | 10.2 | 12.2 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  Snoqualmie Pass, Washington.
          |
  5 mean  | 10.6 | 21.6 |  4.6 | 11.1 |  4.0 | 24.8 | 10.9 | 12.8 |  9.8
    max   | 10.7 | 22.2 |  4.8 | 11.5 |  4.2 | 25.6 | 11.2 | 13.2 | 10.0
    min   | 10.4 | 21.2 |  4.4 | 10.9 |  3.8 | 24.0 | 10.5 | 12.5 |  9.5
          +------+------+------+------+------+------+------+------+------
          |
          |  Alta Lake, 2200 ft., British Columbia.
          |
  5 mean  | 10.6 | 21.6 |  4.3 | 11.3 |  4.1 | 24.7 | 10.8 | 12.7 |  9.7
    max   | 10.9 | 21.9 |  4.6 | 11.5 |  4.3 | 25.0 | 10.9 | 13.1 |  9.8
    min   | 10.5 | 21.2 |  4.2 | 11.0 |  3.9 | 24.4 | 10.7 | 12.3 |  9.6
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps cinereus_, Raft River Mt's, Utah.
          |
  4 mean  | 10.5 | 21.5 |  5.0 | 11.1 |  4.1 | 24.5 | 10.9 | 12.6 |  9.9
    max   | 11.0 | 22.5 |  5.1 | 11.4 |  4.3 | 25.0 | 11.6 | 12.9 | 10.5
    min   | 10.3 | 21.0 |  4.6 | 10.7 |  3.9 | 24.0 | 10.4 | 12.3 |  9.4
          +------+------+------+------+------+------+------+------+------
          |
          |  Mt. Harrison, 10 mi. S Albion, Idaho.
          |
  13 mean | 10.5 | 21.4 |  4.8 | 10.9 |  4.1 | 24.9 | 10.9 | 12.4 | 10.1
     max  | 10.7 | 22.0 |  5.1 | 11.4 |  4.2 | 25.5 | 11.4 | 12.8 | 10.8
     min  | 10.2 | 20.9 |  4.5 | 10.5 |  3.9 | 24.3 | 10.2 | 11.7 |  9.8
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps curtatus_, Pine Forest Mt's, Nevada.
          |
  11 mean | 10.5 | 21.1 |  4.7 | 10.7 |  4.2 | 24.6 | 10.9 | 12.2 |  9.7
     max  | 10.6 | 21.8 |  5.0 | 11.0 |  4.4 | 25.3 | 11.4 | 12.5 | 10.0
     min  | 10.2 | 20.5 |  4.2 | 10.5 |  3.9 | 24.0 | 10.5 | 11.9 |  9.4
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps idahoensis_,
          |  several localities near Cody, Wyoming.
          |
  24 mean | 10.5 | 21.4 |  4.6 | 11.0 |  4.0 | 24.7 | 10.9 | 12.6 |  9.6
     max  | 11.2 | 22.6 |  5.2 | 11.4 |  4.2 | 25.6 | 11.5 | 13.3 | 10.2
     min  |  9.9 | 20.6 |  4.3 | 10.5 |  3.9 | 24.1 | 10.2 | 12.0 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  5 mi. E Warm Lake, 7000 ft., Idaho.
          |
  4 mean  | 10.2 | 21.2 |  4.3 | 11.0 |  4.1 | 24.4 | 10.7 | 12.3 |  9.5
    max   | 10.3 | 21.8 |  4.4 | 11.1 |  4.2 | 24.8 | 11.0 | 12.6 |  9.9
    min   | 10.0 | 20.7 |  4.2 | 10.8 |  4.0 | 23.9 | 10.3 | 12.0 |  9.1
          +------+------+------+------+------+------+------+------+------
          |
          |  Summit Smith Mt'n, 7500 ft., Idaho.
          |
  9 mean  | 10.2 | 21.3 |  4.4 | 10.9 |  4.1 | 24.5 | 10.7 | 12.1 |  9.5
    max   | 10.5 | 22.5 |  4.6 | 11.3 |  4.3 | 25.2 | 11.2 | 12.6 | 10.0
    min   | 10.0 | 20.8 |  4.0 | 10.5 |  3.9 | 23.9 | 10.3 | 11.8 |  9.1
          +------+------+------+------+------+------+------+------+------
          |
          |  2 mi. NE Cooke, 8500 ft., Montana.
          |
  6 mean  | 10.4 | 21.1 |  4.4 | 10.9 |  4.0 | 24.3 | 10.5 | 12.5 |  9.7
    max   | 10.6 | 21.8 |  4.5 | 11.5 |  4.1 | 25.4 | 11.1 | 12.9 | 10.2
    min   | 10.2 | 20.3 |  4.3 | 10.7 |  3.8 | 23.5 |  9.9 | 12.0 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Birch Cr., 18 mi. NE Dillon, 7100 ft., Montana.
          |
  11 mean | 10.3 | 21.3 |  4.3 | 11.0 |  4.0 | 24.5 | 10.8 | 12.6 |  9.6
     max  | 10.6 | 22.2 |  4.6 | 11.6 |  4.3 | 25.5 | 11.5 | 13.0 |  9.9
     min  |  9.7 | 20.7 |  4.0 | 10.6 |  3.8 | 23.7 | 10.3 | 12.4 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps idahoensis_, Waterton Lakes Park, Alberta.
          |
  5 mean  | 10.6 | 21.4 |  4.6 | 10.7 |  4.1 | 24.5 | 10.8 | 12.2 |  9.7
    max   | 10.9 | 22.1 |  4.7 | 11.0 |  4.2 | 25.2 | 11.0 | 12.3 | 10.1
    min   | 10.3 | 21.0 |  4.4 | 10.4 |  4.0 | 24.2 | 10.6 | 11.8 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps kootenayensis_,
          |  near Rossland, British Columbia.
          |
  10 mean | 10.2 | 20.5 |  4.4 | 10.6 |  4.0 | 23.7 | 10.4 | 11.9 |  9.2
     max  | 10.8 | 21.0 |  4.8 | 10.9 |  4.2 | 24.4 | 10.7 | 12.2 |  9.5
     min  |  9.7 | 20.0 |  4.1 | 10.0 |  3.8 | 23.2 |  9.9 | 11.4 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps luteus_, White Mt's, Arizona.
          |
  20 mean | 10.1 | 20.3 |  4.9 | 10.7 |  3.9 | 23.8 | 10.4 | 11.9 |  9.7
     max  | 10.4 | 21.1 |  5.1 | 11.2 |  4.0 | 24.8 | 10.9 | 12.6 | 10.2
     min  |  9.6 | 19.1 |  4.3 | 10.2 |  3.6 | 22.5 |  9.5 | 11.1 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Espanola, 5000 ft., New Mexico.
          |
  3 mean  |  9.8 | 19.8 |  4.7 | 10.5 |  3.7 | 23.4 |  9.9 | 11.5 |  9.5
    max   | 10.0 | 20.1 |  4.8 | 10.6 |  3.8 | 23.7 | 10.3 | 11.6 |  9.7
    min   |  9.7 | 19.5 |  4.5 | 10.3 |  3.6 | 22.9 |  9.6 | 11.4 |  9.4
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps minor_,
          |  2 mi. W Fort Totten, 1400 ft., No. Dakota.
          |
  11 mean |  9.9 | 20.5 |  4.5 | 10.6 |  3.7 | 23.7 | 10.5 | 11.8 |  9.6
     max  | 10.1 | 20.8 |  4.8 | 10.8 |  3.8 | 24.2 | 10.7 | 12.1 |  9.9
     min  |  9.7 | 20.0 |  4.4 | 10.4 |  3.6 | 23.4 | 10.2 | 11.4 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  Near Bottineau, North Dakota.
          |
  4 mean  | 10.1 | 20.9 |  4.6 | 10.6 |  3.8 | 24.1 | 10.8 | 12.3 | 10.0
    max   | 10.2 | 21.3 |  4.7 | 10.9 |  3.8 | 24.5 | 10.9 | 12.5 | 10.2
    min   | 10.1 | 20.6 |  4.5 | 10.4 |  3.7 | 23.8 | 10.7 | 12.1 |  9.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Head Eagle Cr., Bear Paw Mt's, Montana.
          |
  7 mean  | 10.0 | 20.8 |  4.6 | 10.7 |  3.8 | 24.2 | 10.7 | 12.1 |  9.8
    max   | 10.5 | 21.3 |  4.7 | 10.9 |  4.0 | 24.7 | 11.1 | 12.5 | 10.0
    min   |  9.8 | 20.3 |  4.4 | 10.5 |  3.6 | 23.2 | 10.3 | 11.9 |  9.7
          +------+------+------+------+------+------+------+------+------
          |
          |  N Maple Cr., Cypress Hills, Saskatchewan.
          |
  10 mean | 10.1 | 21.2 |  4.6 | 10.7 |  3.9 | 24.5 | 10.9 | 12.3 |  9.8
     max  | 10.4 | 21.7 |  4.9 | 10.8 |  4.0 | 24.8 | 11.3 | 12.7 | 10.0
     min  |  9.9 | 20.4 |  4.4 | 10.5 |  3.6 | 24.0 | 10.5 | 11.8 |  9.6
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps oregonus_,
          |  Parker Cr., Warner Mt's, 5500 ft., Cal.
          |
  12 mean | 10.6 | 21.6 |  4.7 | 11.1 |  4.2 | 25.0 | 11.1 | 12.6 | 10.2
     max  | 11.0 | 22.2 |  4.9 | 11.6 |  4.4 | 25.7 | 11.4 | 13.0 | 10.9
     min  | 10.2 | 21.2 |  4.3 | 10.8 |  4.0 | 24.5 | 10.7 | 12.4 |  9.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Cobb Cr., 6 mi. SW Mt'n City, Nevada.
          |
  12 mean | 10.7 | 21.6 |  5.0 | 11.2 |  4.1 | 25.0 | 11.2 | 12.6 | 10.0
     max  | 11.1 | 22.1 |  5.2 | 11.4 |  4.3 | 25.7 | 11.8 | 13.0 | 10.3
     min  | 10.5 | 21.0 |  4.6 | 10.7 |  3.8 | 24.4 | 10.9 | 12.2 |  9.5
          +------+------+------+------+------+------+------+------+------
          |
          |  Wisconsin Cr., 8000 ft., Nevada.
          |
  10 mean | 10.6 | 21.6 |  4.9 | 11.2 |  4.0 | 24.8 | 11.1 | 12.4 |  9.5
     max  | 10.8 | 22.2 |  5.0 | 11.5 |  4.2 | 25.2 | 11.4 | 12.8 |  9.6
     min  | 10.3 | 21.2 |  4.6 | 10.8 |  3.9 | 24.1 | 10.6 | 12.2 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  North Fork Malheur River,
          |  21 mi. SE Prairie City, 5000 ft., Ore.
          |
  10 mean | 10.6 | 21.5 |  4.7 | 11.3 |  4.2 | 24.8 | 11.0 | 12.7 |  9.9
     max  | 11.2 | 22.3 |  5.2 | 11.6 |  4.4 | 26.2 | 11.7 | 13.2 | 10.9
     min  | 10.0 | 20.8 |  4.3 | 10.9 |  4.0 | 23.5 | 10.5 | 12.4 |  9.7
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps pacificus_,
          |  North Fork Coffee Cr., 4500 ft., Calif.
          |
  8 mean  | 10.4 | 21.5 |  4.7 | 10.9 |  3.9 | 24.8 | 11.1 | 12.5 | 10.0
    max   | 10.8 | 22.4 |  5.0 | 11.4 |  4.0 | 25.2 | 11.4 | 13.2 | 10.5
    min   | 10.0 | 20.7 |  4.5 | 10.7 |  3.8 | 24.0 | 10.5 | 12.0 |  9.6
          +------+------+------+------+------+------+------+------+------
          |
          |  Jackson Lake, 5900 ft., California.
          |
  7 mean  | 10.4 | 21.5 |  4.5 | 11.1 |  4.0 | 24.9 | 11.0 | 12.6 | 10.0
    max   | 10.6 | 22.1 |  4.6 | 11.5 |  4.1 | 25.5 | 11.4 | 12.9 | 10.4
    min   | 10.1 | 20.7 |  4.3 | 10.5 |  3.8 | 23.5 | 10.0 | 12.2 |  9.6
          +------+------+------+------+------+------+------+------+------
          |
          |  Head of Lyle Canyon, 9700 ft., California.
          |
  7 mean  | 10.3 | 20.8 |  4.7 | 10.6 |  3.8 | 24.0 | 10.5 | 12.3 |  9.5
    max   | 10.5 | 21.8 |  5.0 | 11.0 |  4.0 | 24.6 | 10.8 | 12.7 | 10.0
    min   | 10.0 | 20.0 |  4.5 | 10.2 |  3.5 | 23.0 | 10.0 | 11.8 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps princeps_, Florida, Colorado.
          |
  7 mean  | 10.2 | 21.4 |  4.6 | 10.5 |  3.7 | 24.9 | 11.1 | 12.3 |  9.9
    max   | 10.5 | 22.3 |  4.7 | 11.3 |  3.8 | 25.4 | 11.4 | 12.5 | 10.3
    min   |  9.7 | 20.7 |  4.3 |  9.8 |  3.5 | 23.9 | 10.9 | 11.9 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps princeps_, Half Way, Colorado.
          |
  6 mean  | 10.1 | 21.7 |  4.6 | 10.8 |  3.9 | 24.9 | 11.0 | 12.3 |  9.9
    max   | 10.3 | 22.0 |  4.8 | 11.1 |  4.0 | 25.8 | 11.3 | 12.7 | 10.2
    min   | 10.0 | 21.2 |  4.5 | 10.5 |  3.8 | 24.2 | 10.7 | 12.1 |  9.6
          +------+------+------+------+------+------+------+------+------
          |
          |  8 mi. N, 19-1/2 mi. E Savery, Wyoming.
          |
  11 mean | 10.2 | 21.2 |  4.5 | 10.9 |  3.9 | 24.5 | 10.8 | 12.2 |  9.7
     max  | 10.5 | 21.8 |  4.7 | 11.1 |  4.1 | 25.0 | 11.1 | 12.5 | 10.2
     min  | 10.0 | 20.8 |  4.2 | 10.6 |  3.7 | 23.7 | 10.5 | 12.0 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  21-1/2 mi. S, 24-1/2 mi. W Douglas, 7600 ft., Wyoming.
          |
  11 mean | 10.1 | 21.2 |  4.6 | 10.9 |  4.0 | 24.6 | 10.8 | 12.3 |  9.8
     max  | 10.4 | 21.9 |  4.9 | 11.2 |  4.1 | 25.0 | 11.2 | 12.8 | 10.1
     min  |  9.9 | 20.7 |  4.5 | 10.8 |  3.8 | 24.2 | 10.5 | 12.0 |  9.5
          +------+------+------+------+------+------+------+------+------
          |
          |  Medicine Wheel Ranch, 28 mi. E Lovell, 9000 ft., Wyoming.
          |
  20 mean | 10.3 | 21.5 |  4.7 | 11.2 |  4.0 | 24.7 | 11.0 | 12.6 | 10.0
     max  | 10.6 | 22.2 |  4.9 | 11.5 |  4.2 | 25.3 | 11.4 | 12.9 | 10.4
     min  | 10.0 | 20.7 |  4.4 | 10.8 |  3.8 | 24.1 | 10.6 | 12.2 |  9.8
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps saltator_,
          |  Stikine River at Glenora, British Columbia.
          |
  17 mean | 10.4 | 21.3 |  4.4 | 10.9 |  4.1 | 24.3 | 10.7 | 12.5 |  9.6
     max  | 10.7 | 22.2 |  4.5 | 11.4 |  4.5 | 25.0 | 11.4 | 13.0 | 10.0
     min  |  9.8 | 20.5 |  4.1 | 10.6 |  3.8 | 23.3 | 10.3 | 12.0 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  Hazelton, 959 ft., British Columbia.
          |
  15 mean | 10.4 | 21.6 |  4.5 | 11.0 |  4.0 | 24.6 | 10.9 | 12.5 |  9.8
     max  | 10.8 | 22.3 |  4.7 | 11.6 |  4.2 | 25.5 | 11.4 | 12.9 | 10.0
     min  |  9.9 | 20.7 |  4.2 | 10.7 |  3.8 | 23.7 | 10.5 | 11.7 |  9.4
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps utahensis_,
          |  near Robertson, 8700 ft., Wyoming.
          |
  15 mean | 10.7 | 22.0 |  5.0 | 11.2 |  4.1 | 25.4 | 11.1 | 13.2 |  9.9
     max  | 11.1 | 22.6 |  5.1 | 11.6 |  4.2 | 26.4 | 11.7 | 14.0 | 10.3
     min  | 10.3 | 21.0 |  4.7 | 10.8 |  3.9 | 24.6 | 10.8 | 12.4 |  9.6
          +------+------+------+------+------+------+------+------+------
          |
          |  3 mi. N and 11 mi. E Alpine, 5650 ft., Wyoming.
          |
  17 mean | 10.6 | 22.1 |  4.7 | 11.3 |  4.1 | 25.3 | 11.3 | 13.0 |  9.9
     max  | 11.0 | 23.0 |  4.9 | 11.7 |  4.3 | 26.2 | 11.8 | 13.5 | 10.5
     min  | 10.3 | 21.3 |  4.4 1| 0.8 |  4.0 | 24.2 | 10.7 | 12.1 |  9.5
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus princeps utahensis_,
          |  Salamander Lake and Lambs Canyon, 9000 ft., Utah.
          |
  9 mean  | 10.9 | 22.0 |  4.8 | 11.2 |  4.1 | 25.2 | 11.1 | 13.1 | 10.0
    max   | 11.3 | 22.4 |  5.0 | 11.3 |  4.3 | 25.9 | 11.4 | 13.3 | 10.3
    min   | 10.7 | 21.5 |  4.5 | 11.0 |  3.9 | 24.6 | 10.7 | 12.6 |  9.7
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius acadicus_,
          |  vicinity of St. Andrews, New Brunswick.
          |
  4 mean  |  9.6 | 19.8 |  4.1 | 10.2 |  3.5 | 23.0 | 10.1 | 10.8 |  9.5
    max   |  9.8 | 19.9 |  4.2 | 10.3 |  3.7 | 23.1 | 10.2 | 11.1 |  9.7
    min   |  9.2 | 19.7 |  3.9 | 10.0 |  3.3 | 22.8 |  9.9 | 10.4 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  Sebec Lake, Maine.
          |
  3 mean  |  9.6 | 19.5 |  4.3 | 10.0 |  3.5 | 23.0 | 10.0 | 10.7 |  9.2
    max   |  9.8 | 19.8 |  4.5 | 10.1 |  3.6 | 23.3 | 10.1 | 11.3 |  9.4
    min   |  9.4 | 19.0 |  4.0 |  9.7 |  3.4 | 22.6 |  9.9 |  9.9 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  2 mi. S Center Ossipee, New Hampshire.
          |
  10 mean |  9.6 | 19.8 |  4.2 | 10.1 |  3.5 | 23.3 | 10.0 | 10.8 |  9.3
     max  | 10.0 | 20.5 |  4.6 | 10.4 |  3.6 | 24.0 | 10.3 | 11.0 |  9.9
     min  |  9.2 | 18.9 |  3.8 |  9.7 |  3.2 | 22.3 |  9.6 | 10.6 |  8.8
          +------+------+------+------+------+------+------+------+------
          |
          |  Berlin, New York.
          |
  6 mean  |  9.5 | 19.5 |  4.3 | 10.1 |  3.5 | 22.9 |  9.8 | 10.8 |  9.2
    max   |  9.9 | 20.6 |  4.4 | 10.6 |  3.7 | 23.8 | 10.6 | 11.3 |  9.6
    min   |  9.2 | 18.8 |  4.2 |  9.5 |  3.4 | 21.8 |  9.3 | 10.4 |  8.6
          +------+------+------+------+------+------+------+------+------
          |
          |  Lake Kedgemakooge, Nova Scotia.
          |
  5 mean  |  9.5 | 19.9 |  4.2 | 10.3 |  3.5 | 23.4 | 10.2 | 11.3 |  9.4
    max   |  9.7 | 20.1 |  4.3 | 10.4 |  3.5 | 23.5 | 10.4 | 11.4 |  9.5
    min   |  9.3 | 19.7 |  4.0 | 10.3 |  3.4 | 23.3 |  9.9 | 11.0 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius alascensis_, Lake Clark, Alaska.
          |
  2 mean  |  9.5 | 19.3 |  4.3 | 10.0 |  3.6 | 22.8 |  9.9 | 10.7 |  9.2
    max   |  9.6 | 19.6 |  4.4 | 10.0 |  3.6 | 23.0 |  9.9 | 10.7 |  9.2
    min   |  9.4 | 19.1 |  4.2 |  9.9 |  3.5 | 22.6 |  9.9 | 10.7 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  Frosty Peak, Yakutat Bay, Alaska.
          |
  3 mean  |  9.8 | 19.7 |  4.2 | 10.3 |  3.6 | 23.5 | 10.1 | 10.8 |  9.5
    max   | 10.0 | 20.0 |  4.5 | 10.6 |  3.7 | 24.2 | 10.4 | 11.1 |  9.8
    min   |  9.6 | 19.0 |  4.0 |  9.8 |  3.5 | 22.5 |  9.6 | 10.2 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius alascensis_,
          |  7 mi. SSE Haines, 10 ft., Alaska.
          |
  14 mean |  9.9 | 20.0 |  4.2 | 10.4 |  3.6 | 23.7 | 10.2 | 11.0 |  9.4
     max  | 10.1 | 20.5 |  4.4 | 10.8 |  3.7 | 24.6 | 10.7 | 11.4 |  9.8
     min  |  9.8 | 19.5 |  4.0 | 10.2 |  3.4 | 23.0 |  9.8 | 10.4 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  SW end Dezadeash Lake, Yukon.
          |
  2 mean  | 10.0 | 19.8 |  4.5 | 10.5 |  3.6 | 23.5 | 10.2 | 11.3 |  9.6
    max   | 10.1 | 20.1 |  4.5 | 10.5 |  3.6 | 23.8 | 10.4 | 11.3 |  9.7
    min   |  9.8 | 19.5 |  4.4 | 10.5 |  3.5 | 23.2 | 10.0 | 11.2 |  9.5
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius americanus_, Boyne Falls, Michigan.
          |
  8 mean  |  9.5 | 18.7 |  4.1 |  9.7 |  3.3 | 22.0 |  9.5 | 11.0 |  9.1
    max   |  9.8 | 19.4 |  4.3 | 10.0 |  3.4 | 23.2 | 10.0 | 11.4 |  9.3
    min   |  9.3 | 18.3 |  3.8 |  9.4 |  3.0 | 21.5 |  9.0 | 10.3 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Ann Arbor, Michigan.
          |
  3 mean  |  9.5 | 18.6 |  4.2 |  9.9 |  3.3 | 22.0 |  9.5 | 10.9 |  9.0
    max   |  9.6 | 18.8 |  4.4 | 10.0 |  3.3 | 22.4 |  9.8 | 11.0 |  9.1
    min   |  9.4 | 18.5 |  3.8 |  9.8 |  3.2 | 21.9 |  9.3 | 10.8 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Montauk Point, L. I., New York.
          |
  2 mean  |  9.4 | 18.8 |  4.3 |  9.2 |  3.5 | 22.2 |  9.7 | 10.6 |  8.9
    max   |  9.6 | 19.1 |  4.4 |  9.2 |  3.5 | 22.5 |  9.8 | 10.7 |  8.9
    min   |  9.2 | 18.4 |  4.2 |  9.2 |  3.4 | 21.9 |  9.5 | 10.5 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Mays Landing, New Jersey.
          |
  2 mean  |  9.4 | 18.8 |  4.4 |  9.8 |  3.4 | 22.1 |  9.6 | 10.9 |  8.5
    max   |  9.5 | 18.8 |  4.4 |  9.8 |  3.5 | 22.2 |  9.7 | 11.0 |  8.7
    min   |  9.3 | 18.7 |  4.4 |  9.8 |  3.2 | 22.0 |  9.5 | 10.8 |  8.2
          +------+------+------+------+------+------+------+------+------
          |
          |  Laurel, Maryland.
          |
  3 mean  |  9.1 | 18.6 |  4.3 |  9.6 |  3.3 | 22.0 |  9.5 | 10.6 |  8.7
    max   |  9.3 | 18.9 |  4.5 |  9.7 |  3.3 | 22.0 |  9.7 | 10.8 |  8.9
    min   |  8.9 | 18.2 |  4.1 |  9.5 |  3.3 | 21.9 |  9.2 | 10.4 |  8.6
          +------+------+------+------+------+------+------+------+------
          |
          |  Hampton, Virginia.
          |
  3 mean  |  9.0 | 18.8 |  4.1 |  9.7 |  3.3 | 21.9 |  9.4 | 10.6 |  9.0
    max   |  9.3 | 18.9 |  4.1 |  9.8 |  3.3 | 22.0 |  9.6 | 11.1 |  9.2
    min   |  8.6 | 18.5 |  4.0 |  9.6 |  3.2 | 21.8 |  9.2 | 10.0 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius americanus_, Raleigh, North Carolina.
          |
  3 mean  |  9.2 | 18.8 |  4.0 |  9.9 |  3.4 | 22.4 |  9.6 | 10.9 |  8.9
    max   |  9.6 | 19.7 |  4.2 | 10.4 |  3.5 | 23.0 |  9.9 | 10.9 |  9.4
    min   |  8.8 | 17.9 |  3.9 |  9.4 |  3.2 | 21.8 |  9.4 | 10.8 |  8.5
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius campestris_,
          |  3 mi. NW Sundance, 5900 ft., Wyo.
          |
  19 mean |  9.7 | 19.9 |  4.3 | 10.4 |  3.6 | 23.2 | 10.0 | 11.1 |  9.5
     max  | 10.0 | 20.8 |  4.5 | 10.9 |  3.8 | 24.2 | 10.5 | 11.8 | 10.0
     min  |  9.4 | 19.2 |  3.8 | 10.1 |  3.4 | 22.4 |  9.5 | 10.7 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  Palmer Gulch, Black Hills, South Dakota.
          |
  11 mean |  9.8 | 20.2 |  4.3 | 10.5 |  3.7 | 23.4 | 10.1 | 11.4 |  9.6
     max  | 10.2 | 21.4 |  4.5 | 11.1 |  3.9 | 24.9 | 10.9 | 12.0 | 10.2
     min  |  9.5 | 19.0 |  4.2 | 10.1 |  3.5 | 21.9 |  9.5 | 10.7 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius canadensis_, St. Methode, Quebec.
          |
  4 mean  |  9.6 | 19.2 |  4.3 | 10.1 |  3.6 | 22.6 |  9.8 | 10.9 |  9.1
    max   |  9.9 | 19.7 |  4.5 | 10.2 |  3.7 | 23.5 | 10.1 | 11.2 |  9.4
    min   |  9.1 | 18.5 |  3.9 |  9.9 |  3.3 | 21.7 |  9.5 | 10.7 |  8.7
          +------+------+------+------+------+------+------+------+------
          |
          |  Pancake Bay, Algoma District, Ontario.
          |
  11 mean |  9.6 | 18.8 |  4.1 | 10.0 |  3.5 | 22.2 |  9.6 | 10.4 |  9.2
     max  | 10.0 | 19.4 |  4.4 | 10.3 |  3.6 | 22.8 |  9.7 | 10.6 |  9.7
     min  |  9.2 | 18.3 |  3.8 |  9.6 |  3.3 | 21.8 |  9.2 |  9.8 |  8.6
          +------+------+------+------+------+------+------+------+------
          |
          |  Franz, Ontario.
          |
  5 mean  |  9.8 | 19.4 |  4.2 | 10.3 |  3.5 | 22.6 |  9.8 | 10.7 |  9.0
    max   | 10.0 | 19.8 |  4.3 | 10.5 |  3.6 | 23.2 | 10.2 | 11.1 |  9.3
    min   |  9.6 | 18.9 |  4.1 | 10.2 |  3.4 | 22.1 |  9.6 | 10.4 |  8.8
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius hudsonius_, Fort Severn, Ontario.
          |
  4 mean  |  9.9 | 19.3 |  4.2 |  9.9 |  3.5 | 22.7 |  9.6 | 10.9 |  9.2
    max   | 10.1 | 19.7 |  4.3 | 10.1 |  3.6 | 23.3 |  9.8 | 11.0 |  9.3
    min   |  9.8 | 19.0 |  4.0 |  9.7 |  3.4 | 22.0 |  9.3 | 10.7 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Oxford House, Manitoba.
          |
  6 mean  |  9.6 | 19.1 |  4.4 |  9.9 |  3.5 | 22.3 |  9.7 | 10.4 |  9.2
    max   |  9.9 | 19.8 |  4.6 | 10.1 |  3.7 | 23.1 | 10.0 | 10.8 |  9.6
    min   |  9.3 | 18.7 |  4.2 |  9.6 |  3.3 | 21.7 |  9.5 |  9.8 |  8.8
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius hudsonius_, Emma Lake, Saskatchewan.
          |
  2 mean  |  9.8 | 19.4 |  4.3 |  9.9 |  3.6 | 22.7 |  9.8 | 10.9 |  9.0
    max   |  9.8 | 19.5 |  4.3 |  9.9 |  3.6 | 22.9 |  9.9 | 10.9 |  9.1
    min   |  9.8 | 19.3 |  4.2 |  9.9 |  3.5 | 22.4 |  9.6 | 10.9 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Lac la Nonne, Alberta.
          |
  4 mean  |  9.8 | 19.1 |  4.2 | 10.0 |  3.4 | 22.4 |  9.7 | 10.5 |  9.1
    max   |  9.8 | 19.4 |  4.2 | 10.0 |  3.5 | 22.6 |  9.9 | 10.5 |  9.2
    min   |  9.7 | 18.8 |  4.1 |  9.9 |  3.3 | 22.2 |  9.6 | 10.5 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  1 mi. NW Junct. Irons Cr. and Laird River,
          |  British Columbia.
          |
  3 mean  |  9.6 | 19.0 |  4.3 |  9.9 |  3.5 | 22.2 |  9.7 | 10.6 |  9.1
    max   |  9.6 | 19.3 |  4.3 | 10.1 |  3.5 | 22.6 |  9.8 | 10.9 |  9.3
    min   |  9.5 | 18.7 |  4.3 |  9.7 |  3.4 | 21.7 |  9.5 | 10.3 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius intermedius_, Blackner, North Dakota.
          |
  2 mean  | 10.1 | 19.6 |  4.3 | 10.0 |  3.6 | 22.7 |  9.9 | 11.1 |  9.4
    max   | 10.1 | 20.0 |  4.4 | 10.4 |  3.7 | 23.2 |  9.9 | 11.4 |  9.7
    min   | 10.0 | 19.1 |  4.1 |  9.8 |  3.4 | 22.2 |  9.8 | 10.8 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Cannon Ball, North Dakota.
          |
  2 mean  |  9.8 | 19.1 |  4.4 | 10.1 |  3.6 | 22.0 |  9.5 | 11.0 |  9.1
    max   |  9.9 | 19.1 |  4.4 | 10.2 |  3.7 | 22.4 |  9.8 | 11.3 |  9.2
    min   |  9.6 | 19.0 |  4.3 |  9.9 |  3.4 | 21.8 |  9.2 | 10.7 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Elk River, Minnesota.
          |
  8 mean  |  9.5 | 19.2 |  4.2 |  9.9 |  3.4 | 22.5 |  9.6 | 10.6 |  9.2
    max   |  9.7 | 19.6 |  4.3 | 10.0 |  3.6 | 23.0 |  9.9 | 11.0 |  9.5
    min   |  9.2 | 18.9 |  4.0 |  9.9 |  3.3 | 22.1 |  9.4 | 10.2 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  E Okeboji Lake, Iowa.
          |
  3 mean  |  9.6 | 19.3 |  4.2 |  9.9 |  3.4 | 22.2 |  9.3 | 10.2 |  9.4
    max   |  9.8 | 19.3 |  4.2 | 10.0 |  3.4 | 22.2 |  9.3 | 10.2 |  9.7
    min   |  9.4 | 19.3 |  4.2 |  9.8 |  3.4 | 22.2 |  9.2 | 10.2 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  Turkey Run State Park, Indiana.
          |
  2 mean  |  9.5 | 18.9 |  4.2 |  9.6 |  3.5 | 22.3 |  9.8 | 10.4 |  9.0
    max   |  9.6 | 18.9 |  4.4 |  9.6 |  3.6 | 22.4 |  9.8 | 10.8 |  9.0
    min   |  9.4 | 18.9 |  4.0 |  9.6 |  3.3 | 22.2 |  9.8 | 10.0 |  9.0
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius intermedius_,
          |  Jordan Cr., 3 mi. NE Fairmont, Ill.
          |
  5 mean  |  9.6 | 19.4 |  4.1 | 10.1 |  3.6 | 22.6 | 10.0 | 10.7 |  9.2
    max   |  9.9 | 19.8 |  4.2 | 10.3 |  3.8 | 23.4 | 10.5 | 11.6 |  9.6
    min   |  9.3 | 18.9 |  4.0 | 10.0 |  3.4 | 21.9 |  9.5 | 10.3 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  Rib Hill, Wisconsin.
          |
  5 mean  |  9.6 | 19.0 |  4.3 | 10.1 |  3.4 | 22.6 |  9.7 | 10.8 |  9.0
    max   | 10.0 | 19.8 |  4.4 | 10.5 |  3.6 | 23.7 | 10.2 | 11.2 |  9.3
    min   |  9.4 | 18.4 |  4.1 |  9.7 |  3.2 | 21.9 |  9.4 | 10.3 |  8.7
          +------+------+------+------+------+------+------+------+------
          |
          |  Lake St. Germain, Wisconsin.
          |
  5 mean  |  9.7 | 18.9 |  4.1 | 10.1 |  3.5 | 22.5 |  9.6 | 10.5 |  9.0
    max   |  9.9 | 19.5 |  4.3 | 10.2 |  3.6 | 23.2 | 10.0 | 10.8 |  9.3
    min   |  9.5 | 18.4 |  3.9 |  9.8 |  3.3 | 21.8 |  9.0 | 10.2 |  8.5
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius ladas_, Northwest River, Labrador.
          |
  6 mean  |  9.5 | 19.0 |  4.2 | 10.2 |  3.6 | 22.4 |  9.7 | 10.9 |  9.0
    max   |  9.6 | 20.0 |  4.4 | 10.3 |  3.6 | 23.2 | 10.2 | 11.0 |  9.4
    min   |  9.3 | 18.4 |  4.0 | 10.0 |  3.5 | 21.5 |  9.4 | 10.6 |  8.8
          +------+------+------+------+------+------+------+------+------
          |
          |  Moisie Bay, Labrador.
          |
  4 mean  |  9.8 | 19.1 |  4.3 | 10.0 |  3.4 | 22.8 |  9.6 | 11.0 |  9.1
    max   |  9.8 | 19.7 |  4.4 | 10.0 |  3.5 | 23.5 | 10.1 | 11.3 |  9.8
    min   |  9.7 | 18.6 |  4.1 |  9.9 |  3.3 | 22.1 |  9.3 | 10.8 |  8.9
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius pallidus_, Mohawk Park, Oklahoma.
          |
  2 mean  |  9.7 | 18.4 |  4.3 |  9.9 |  3.7 | 21.5 |  9.3 | 11.0 |  8.7
    max   | 10.1 | 18.8 |  4.3 |  9.9 |  3.7 | 21.8 |  9.4 | 11.0 |  8.7
    min   |  9.3 | 18.0 |  4.3 |  9.8 |  3.7 | 21.1 |  9.2 | 11.0 |  8.6
          +------+------+------+------+------+------+------+------+------
          |
          |  vicinity of Lawrence, Kansas.
          |
  10 mean |  9.2 | 18.8 |  4.4 |  9.8 |  3.4 | 21.6 |  9.7 | 10.9 |  9.0
     max  |  9.5 | 19.4 |  4.8 | 10.2 |  3.6 | 22.4 | 10.1 | 11.6 |  9.4
     min  |  8.9 | 18.1 |  4.0 |  9.3 |  3.3 | 21.0 |  9.0 | 10.3 |  8.8
          +------+------+------+------+------+------+------+------+------
          |
          |  2 mi. S Schuyler, Nebraska.
          |
  1       |  9.2 | 18.5 |  4.4 |  9.5 |  3.3 | 21.5 |  9.6 | 10.4 |  9.1
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius pallidus_,
          | Valentine National Wildlife Refuge, Nebraska.
          |
  1       | 10.0 | 19.6 |  4.5 | 10.5 |  3.5 | 22.9 | 10.0 | 11.6 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius preblei_, Loveland, Colorado.
          |
  2 mean  |  9.6 | 18.5 |  4.1 | 10.0 |  3.6 | 22.3 |  9.6 | 10.4 |  9.1
    max   |  9.6 | 19.0 |  4.2 | 10.0 |  3.6 | 22.4 |  9.8 | 10.6 |  9.1
    min   |  9.5 | 18.0 |  3.9 | 10.0 |  3.6 | 22.2 |  9.4 | 10.2 |  9.1
          +------+------+------+------+------+------+------+------+------
          |
          |  Spring Hill, 12 mi. N Laramie Peak, 6300 ft., Wyoming.
          |
  1       |  9.8 | 19.2 |  4.1 | 10.2 |  3.6 | 22.8 | 10.2 | 10.7 |  9.3
          +------+------+------+------+------+------+------+------+------
          |
          |  _Zapus hudsonius tenellus_,
          |  Hazelton, 959 ft., British Columbia.
          |
  2 mean  |  9.6 | 19.4 |  4.4 | 10.1 |  3.5 | 22.9 |  9.6 | 10.9 |  9.2
    max   |  9.6 | 19.5 |  4.4 | 10.2 |  3.5 | 23.0 |  9.6 | 10.9 |  9.2
    min   |  9.6 | 19.3 |  4.3 | 10.0 |  3.4 | 22.7 |  9.6 | 10.8 |  9.2
          +------+------+------+------+------+------+------+------+------
          |
          |  Cottonwood P. O., British Columbia.
          |
  2 mean  |  9.5 | 19.5 |  4.4 | 10.1 |  3.5 | 22.8 |  9.7 | 10.8 |  9.2
    max   |  9.6 | 19.6 |  4.5 | 10.2 |  3.5 | 22.8 |  9.8 | 10.9 |  9.3
    min   |  9.3 | 19.4 |  4.2 | 10.0 |  3.4 | 22.7 |  9.6 | 10.7 |  9.1
          +------+------+------+------+------+------+------+------+------
          |
          |  S end Swan Lake, British Columbia.
          |
  2 mean  |  9.4 | 19.7 |  4.1 | 10.0 |  3.6 | 22.9 | 10.1 | 10.9 |  9.5
    max   |  9.4 | 19.7 |  4.2 | 10.2 |  3.6 | 23.2 | 10.2 | 10.9 |  9.6
    min   |  9.3 | 19.6 |  4.0 |  9.8 |  3.5 | 22.6 | 10.0 | 10.8 |  9.4
          +------+------+------+------+------+------+------+------+------
          |
          |  Indianpoint Lake, 15 mi. NE Barkerville, British Columbia.
          |
  4 mean  |  9.6 | 18.9 |  4.1 |  9.9 |  3.4 | 21.9 |  9.5 | 10.8 |  9.0
    max   |  9.6 | 19.6 |  4.2 | 10.0 |  3.6 | 23.0 |  9.8 | 11.3 |  9.4
    min   |  9.4 | 18.3 |  4.0 |  9.8 |  3.3 | 21.3 |  9.1 | 10.2 |  8.8
  --------+------+------+------+------+------+------+------+------+------




LITERATURE CITED


ALLEN, J. A.

  1894.  Cranial variation in _Neotoma micropus_ due to growth and
         individual differentiation. Bull. Amer. Mus. Nat. Hist.,
         6:233-246, 1 pl., August 3, 1894.


ANDERSON, R. M.

  1932.  Five new mammals from British Columbia. Ann. Rept. 1931, Nat.
         Mus. Canada: 99-119, 1 pl., November 24, 1932.
  1942.  Six additions to the list of Quebec mammals with descriptions of
         four new forms. Ann. Rept. Prov. Soc. Nat. Hist. for 1941:31-42,
         July 14, 1942.


AXELROD, D. I.

  1948.  Climate and evolution in western North America during Middle
         Pliocene time. Evol., 2:127-144, July 2, 1948.


BAILEY, B.

  1929.  Mammals of Sherburne County, Minnesota. Jour. Mamm., 10:153-164,
         May 9, 1929.


BAILEY, J. W.

  1946.  The mammals of Virginia. Williams Printing Company, Richmond,
         Virginia, xii + 416 pp., 96 figs. in text, December, 1946.


BAILEY, V.

  1923.  Mammals of the District of Columbia. Proc. Biol. Soc. Washington,
         36:103-138, May 1, 1923.
  1927.  A biological survey of North Dakota. N. Amer. Fauna, 49:vi +
         226 pp., 1 map, 21 pls., 8 figs. in text, January 8, 1927.
  1932.  Mammals of New Mexico. N. Amer. Fauna, 53:1-412, 22 pls., 58
         figs. in text, March 1, 1932.
  1936.  The mammals and life zones of Oregon. N. Amer. Fauna, 55:1-416,
         1 map, 52 pls., 102 figs. in text, August 29, 1936.


BATCHELDER, C. F.

  1899.  Some unrecognized jumping mice of the genus _Zapus_. Proc. New
         England Zool. Club, 1:3-7, February 8, 1899.

BLAIR, F. W.

  1940.  Home ranges and populations of the jumping mouse. Amer. Midland
         Nat., 23:244-250, 1 table, January, 1940.


BOLE, B. P., JR., and MOULTHROP, P. N.

  1942.  The Ohio Recent mammal collection in the Cleveland Museum of
         Natural History. Scientific Publs., Cleveland Mus. Nat. Hist.,
         5:83-181, September 11, 1942.

BORELL, A., and ELLIS, R.

  1934.  Mammals of the Ruby Mountains region of northeastern Nevada.
         Jour. Mamm., 15:12-44, 6 pls., 1 fig. in text, 4 tables,
         February 15, 1934.


BRIMLEY, C. S.

  1923.  Breeding dates of small mammals at Raleigh, North Carolina. Jour.
         Mamm., 4:263-264, November 1, 1923.


CARL, G. C., GUIGUET, C. J., and HARDY, G. A.

  1952.  A natural history survey of the Manning Park area British
         Columbia. Occ. Papers British Columbia Prov. Mus., 9:1-130,
         22 figs. in text, July, 1952.


CHRISTIAN, J. J.

  1936.  Mammals caught in post holes. Jour. Mamm., 17:416, November
         16, 1936.


COCKRUM, E. L., and BAKER, R. H.

  1950.  A new jumping mouse (genusi _Zapus_) from Kansas. Proc. Biol.
         Soc. Washington, 63:1-4, 1 fig. in text, April 26, 1950.


COLEMAN, R. H.

  1941.  _Zapus hudsonius americanus_ in South Carolina. Jour. Mamm.,
         22:91, February 14, 1941.


COPE, E. D.

  1871.  Preliminary report on the Vertebrata discovered in the Port
         Kennedy Bone Cave. Proc. American Philos. Soc., 12:73-102,
         20 figs., April 7, 1871.


CORY, C. B.

  1912.  The mammals of Illinois and Wisconsin. Field Mus. Nat. Hist.
         Publ. 153, zool. ser., 11:1-505, many unnumbered pls., figs.
         and maps in text, 1912.


CROWE, P. E.

  1943.  Notes on some mammals of the southern Canadian Rocky Mountains.
         Bull. Amer. Mus. Nat. Hist., 80:391-410, 4 pls., 1 fig. in
         text, February 4, 1943.


DALQUEST, W. W.

  1948.  Mammals of Washington. Univ. Kansas Publ., Mus. Nat. Hist.,
         2:1-444, 140 figs. in text, April 9, 1948.


DAVIS, W. B.

  1939.  The Recent mammals of Idaho. The Caxton Printers, Caldwell,
         Idaho, 444 pp., 2 full page half tones, 33 figs. in text,
         April 5, 1939.


DEARBORN, N.

  1932.  Foods of some predatory fur-bearing animals of Michigan. Univ.
         Michigan School of Forestry and Conservation, Bull. 1:1-52,
         8 figs., 22 charts, 10 maps, 1932.


DICE, L. R.

  1932.  Mammals collected by F. M. Gaige in 1919 at Lake Cushman and
         vicinity, Olympic Peninsula, Washington. Murrelet, 13:47-49,
         May, 1932.


DURRANT, S. D.

  1952.  Mammals of Utah, taxonomy and distribution. Univ. Kansas Publ.,
         Mus. Nat. Hist., 6, 1-549, 91 figs. in text, 30 tables,
         August 10, 1952.


EADIE, R. W.

  1949.  Hibernating meadow jumping mouse. Jour. Mamm., 30:307-308,
         August 17, 1949.


EDSON, J. M.

  1932.  Hibernation of the northwest jumping mouse. Murrelet, 13:55-56,
         May, 1932.


ELLERMAN, J. R.

  1940.  The families and genera of living Rodents. British Mus. (Nat.
         Hist.), Vol. 1, pp. xxvi + 689, 189 figs., June 8, 1940.


ELLIOT, D. G.

  1898.  Lists of species of mammals principally rodents obtained by W.
         W. Price, Dr. S. E. Meek, G. R. Cherrie, and E. S. Thompson in
         the states of Iowa, Wyoming, Montana, Idaho, Nevada, and
         California with descriptions of new species. Field Columbian
         Mus. Publ. 27, zool. ser. 1:193-221, March, 1898.

  1899.  Catalogue of mammals from the Olympic Mountains, Washington
         with descriptions of new species. Field Columbian Mus. Publ. 32,
         zool. ser., 1:241-276, 21 pls., 13 unnumbered figs. in text,
         March, 1899.


ERICKSON, A. B.

  1938.  Parasites of some Minnesota rodents. Jour. Mamm., 19:252-253,
         May 12, 1938.


FLAHAUT, M. R.

  1939.  Unusual location of hibernating jumping mice. Murrelet, 20:17-18,
         1 unnumbered pl., April 30, 1939.


GIDLEY, I. W., and GAZIN, C. L.

  1938.  The Pleistocene vertebrate fauna from Cumberland Cave, Maryland.
         U. S. Nat. Mus. Bull., 171:1-93, 50 figs., 25 tables,
         January 25, 1938.


GOODWIN, G. G.

  1924.  Mammals of the Gaspé Peninsula, Quebec. Jour. Mamm., 5:246-257,
         2 pls., November 15, 1924.

  1935.  The mammals of Connecticut. Bull. Connecticut State Geol. and
         Nat. Hist. Surv., 53:1-221, 33 pls., 19 figs. in text, 1935.


GRINNELL, J., DIXON, J., and LINSDALE, J. M.

  1930.  Vertebrate natural history of a section of northern California
         through the Lassen Peak Region. Univ. California Publ. Zool.,
         35:v + 594, 181 figs. in text, October 10, 1930.

  1937.  Fur-bearing mammals of California.... Univ. California
         Press, 2 vols., xii + 375, pls. 1-7, figs. 1-138, xiv + 377-777,
         pls. 8-13, figs. 139-345, July 22, 1937.


GRIZZELL, R. A., JR.

  1949.  Hibernating jumping mice in woodchuck dens. Jour. Mamm.,
         30:74-75, February 14, 1949.


HALL, E. R.

  1930.  Rodents and lagomorphs from the Later Tertiary of Fish Lake
         Valley, Nevada. Univ. California Publ. Bull. Dept. Geol. Sci.,
         19:295-312, 1 pl., 29 figs. in text, November 25, 1930.

  1931.  Critical comments on mammals from Utah with descriptions of new
         forms from Utah, Nevada and Washington. Univ. California
         Publ. Zool., 37:1-13, April 10, 1931.

  1934.  Mammals collected by T. T. and E. B. McCabe in the Bowron
         Lake Region of British Columbia. Univ. California Publ. Zool.,
         40:363-386, 1 fig. in text, November 5, 1934.

  1946.  Mammals of Nevada. Univ. California Press, Berkeley, xi + 710,
         colored frontispiece, 11 pls., 485 figs. in text, plus
         unnumbered silhouettes and maps, July 1, 1946.


HALL, E. R., and DAVIS, W. B.

  1934.  Notes on Arizona rodents. Proc. Biol. Soc. Washington, 47:51-56,
         1 fig. in text, February 9, 1934.


HAMILTON, W. J.

  1935.  Habits of jumping mice. Amer. Midland Nat., 16:187-200, 1 pl.,
         2 figs. in text, 1935.


HANDLEY, C. O., JR., and PATTON, C. P.

  1947.  Wild mammals of Virginia. Commonwealth of Virginia, Comm.
         Game and Inland Fisheries, Richmond, vi + 220 pp., frontispiece,
         103 figs. in text, 1947.


HARPER, F.

  1932.  Mammals of the Athabaska and Great Slave lakes region.
         Jour. Mamm., 13:19-36, 3 pls., February 9, 1932.


HAUSMAN, L. A.

  1920.  Structural characteristics of the hair of mammals. Amer. Nat.,
         54:496-523, 7 pls., November-December, 1920.


HIBBARD, C. W.

  1941.  The Borchers Fauna a new Pleistocene interglacial fauna from
         Meade County, Kansas. Univ. Kansas Publ. State Geol. Surv.
         Kansas, Bull., 38:197-220, 2 pls., July 14, 1941.

  1951.  A new jumping mouse from the Upper Pliocene of Kansas. Jour.
         Mamm., 32:351-352, 1 fig. in text, August 23, 1951.


HOFFMEISTER, D. F.

  1951.  A taxonomic and evolutionary study of the piñon mouse,
         _Peromyscus truei._ Illinois Biol. Monog., 21:ix + 104 pp.,
         5 pls., 24 figs. in text, 7 tables, November 12, 1951.


HOLLISTER, N.

  1912.  Mammals of the Alpine Club expedition to the Mount Robson
         Region. Alpine Club of Canada, Spec. No.:1-44, 13 pls. in text,
         1912.


HOOPER, E. T.

  1944.  San Francisco Bay as a factor influencing speciation in rodents.
         Univ. Michigan, Mus. Zool., Miscl. Publ., 59:1-89, 5 pls.,
         18 maps, January 12, 1944.

  1952.  A systematic review of the harvest mice (genus _Reithrodontomys_)
         of Latin America. Miscl Publ. Mus. Zool. Univ. Michigan, 77:1-255,
         9 pls., 24 figs. in text, 7 tables, 12 maps, January 16, 1952.


HOWELL, A. B.

  1920.  A study of the California jumping mice of the genus Zapus. Univ.
         California Publ. Zool., 21:225-238, 1 fig. in text, May 20, 1920.


IVOR, H. R.

  1934.  Notes on the rearing of captive young meadow jumping mice.
         Canadian Field-Nat., 48:8-10, January 15, 1934.


KELLOGG, L.

  1916.  Report upon mammals and birds found in portions of Trinity,
         Siskiyou and Shasta counties, California. Univ. California Publ.
         Zool., 12:335-398, 4 pls., 1 fig., January 27, 1916.


LINSDALE, J. M.

  1938.  Environmental responses of vertebrates in the Great Basin. Amer.
         Midland Nat., 19:1-206, 12 figs. in text, January, 1938.


LYON, M. W., JR.

  1938.  Mammals of Indiana. Amer. Midland Nat., 17:1-384, 125 figs. in
         text, 85 maps, January, 1936.


MATTHEW, W. D.

  1915.  Climate and evolution. New York Acad. Sci., 24:171-318, 33 figs.,
         17 tables, February 18, 1915.


MAYR, E.

  1942.  Systematics and the origin of species from the viewpoint of a.
         zoologist Columbia Univ. Press, New York, xiv + 334 pp.,
         29 figs., 1942.


MERRIAM, C. H.

  1897a. Three new jumping mice (_Zapus_) from the Northwest. Proc. Biol.
         Soc. Washington, 11:103-104, April 26, 1897.

  1897b. Mammals of Mount Mazama, Oregon. Mazama, 1:204-230, 10
         pls., 1 map, October, 1897.


MILLER, G. S., JR.

  1899.  Preliminary list of New York mammals. Bull. New York State
         Mus., 6:273-390, November 18, 1899.

  1911.  A new jumping mouse from New Mexico. Proc. Biol. Soc. Washington,
         24:253-254, December 23, 1911.


MOOJEN, J.

  1948.  Speciation in the Brazilian spiny rats (genus _Proechimys_,
         family Echimyidae). Univ. Kansas Publ. Mus. Nat. Hist.,
         1:301-406, 140 figs. in text, 1 table, December 10, 1948.


MOORE, A. W.

  1928.  _Zapus princeps princeps_ in Utah. Jour. Mamm., 9:154-155,
         May 9, 1928.


NICHOLSON, A. J.

  1937.  A hibernating jumping mouse. Jour. Mamm., 18:103, February
         11, 1937.


PEARSON, O. P., and PEARSON, A. K.

  1947.  Owl predation in Pennsylvania, with notes on the small mammals
         of Delaware County. Jour. Mamm., 28:137-147, 1 fig., 3 tables,
         June 1, 1947.


PETRIDES, G. A.

  1948.  The jumping mouse in Georgia. Jour. Mamm., 29:75-76, February
         13, 1948.


PREBLE, E. A.

  1899.  Revision of the jumping mice of the genus _Zapus_. N. Amer.
         Fauna, 15:1-42, 1 pl., 4 figs. in text, August 8, 1899.


PREBLE, N. A.

  1944.  A swimming jumping mouse. Jour. Mamm., 25:200-201, May
         26, 1944.


QUIMBY, D. C.

  1951.  The life history and ecology of the jumping mouse, _Zapus
         hudsonius_. Ecol. Monog., 21:61-95, 14 figs. in text, 7 tables,
         January, 1951.


RIDGWAY, R.

  1912.  Color standards and color nomenclature. Washington, D. C.,
         privately printed, iv + 44 pp., 53 pls., 1912.


SCHMIDT, F. J. W.

  1931.  Mammals of western Clark County, Wisconsin. Jour. Mamm.,
         12:99-117, 1 map, May 14, 1931.


SCHWARTZ, C. W.

  1951.  A new record of _Zapus hudsonius_ in Missouri and notes on its
         hibernation. Jour. Mamm., 32:227-228, May 21, 1951.


SHELDON, C.

  1934.  Studies of the life histories of _Zapus_ and _Napaeozapus_ in Nova
         Scotia. Jour. Mamm., 15:290-300, November 15, 1934.

  1938.  Vermont jumping mice of the genus _Zapus._ Jour. Mamm.,
         19:324-332, 4 figs. in text, August 18, 1938.


SIMPSON, G. G.

  1947.  Holarctic mammalian faunas and continental relationships during
         the Cenozoic. Bull. Geol. Soc. America, 58:613-688, 6 figs. in
         text, 9 tables, July, 1947.


SMITH, C. F., and HOPKINS, C. L.

  1937.  Notes on the barn owls of the San Francisco Bay Region. Condor,
         39:189-191, September 15, 1937.


STANFORD, J. S.

  1931.  Notes on small mammals of Utah. Jour. Mamm., 12:356-363,
         November 11, 1931.


STEHLIN, H. G., and SCHAUB, S.

  1951.  Die Trigondontie der simplicidentaten Nager. Schweizerischen
         Paleont. Abhandl., Basel, 67:1-385, 620 text figuren.


STONER, D.

  1918.  The rodents of Iowa. Iowa Geol. Surv., Bull., 5:1-172, 37 figs.
         in text, 1918.


SURFACE, H. A.

  1906.  The serpents of Pennsylvania. Monthly Bull. Div. Zool.,
         Pennsylvania State Dept. Agric., 4:113-208, pls. 15-42, 23 figs.
         in text, August and September, 1906.


SVIHLA, A., and SVIHLA, R. D.

  1933.  Notes on the jumping mouse _Zapus trinotatus trinotatus_ Rhoads.
         Jour. Mamm., 14:131-134, May 15, 1933.


SVIHLA, R. D.

  1931.  Mammals of the Uinta Mountain Region. Jour. Mamm., 12:256-266,
         1 pl., 1 fig. in text, August 24, 1931.


TAYLOR, W. P.

  1911.  Mammals of the Alexander Nevada Expedition of 1909. Univ.
         California Publ. Zool., 7:205-307, 2 figs. in text, June 24, 1911.

  1922.  A distributional and ecological study of Mount Rainier,
         Washington. Ecol., 3:213-236, 4 figs. in text, July, 1922.


TEST, F. H., and TEST, A.

  1943.  Incidence of dipteran parasitosis in populations of small mammals.
         Jour. Mamm., 24:506-508, November 20, 1943.


TOWNSEND, M. T.

  1935.  Studies on some of the small mammals of central New York.
         Roosevelt Wildlife Annals, 4(No. 1):1-120, 8 pls., 22 figs.
         in text, 35 tables, 4 maps, December, 1935.


VERGEER, T.

  1948.  Frog catches mouse in natural environment. Turtox News, 26:91,
         March, 1948.


VINOGRADOV, B. S.

  1925.  On the structure of the external genitalia in Dipodidae and
         Zapodidae (Rodentia) as a classificatory character. Proc. Zool.
         Soc. London, Part 1:577-585, 6 pls., 1925.


WHITLOW, W. B., and HALL, E. R.

  1933.  Mammals of the Pocatello Region of southeastern Idaho. Univ.
         California Publ. Zool., 40:235-276, 3 figs. in text,
         September 30, 1933.


WILLIAMS, C. S.

  1938.  Aids to the identification of mole and shrew hairs with general
         comments on hair structure and hair determination. Jour. Wildl.
         Mgt., 2:239-250, 1 pl., 9 figs. in text, October, 1943.


WILSON, R. W.

  1936.  A Pliocene rodent fauna from Smiths Valley, Nevada. Carnegie
         Inst. Publ., 473:15-34, 2 pls., May 21, 1936.

  1937.  Pliocene rodents of western North America. Carnegie Inst. Publ.,
         487:21-73, 2 figs. in text, July 23, 1937.


_Transmitted October 9, 1953._




UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY


Institutional libraries interested in publications exchange may obtain
this series by addressing the Exchange Librarian, University of Kansas
Library, Lawrence, Kansas. Copies for individuals, persons working in a
particular field of study, may be obtained by addressing instead the
Museum of Natural History, University of Kansas, Lawrence, Kansas. There
is no provision for sale or this series by the University Library which
meets institutional requests, or by the Museum of Natural History which
meets the requests of individuals. However, when individuals request
copies from the Museum, 25 cents should be included, for each separate
number that is 100 pages or more in length, for the purpose of defraying
the costs of wrapping and mailing.

* An asterisk designates those numbers of which the Museum's supply (not
the Library's supply) is exhausted. Numbers published to date, in this
series, are as follows:

   Vol. 1.  1. The pocket gophers (Genus Thomomys) of Utah. By Stephen
               D. Durrant. Pp. 1-82, 1 figure in text. August 15, 1946.

            2. The systematic status of Eumeces pluvialis Cope, and
               noteworthy records of other amphibians and reptiles from
               Kansas and Oklahoma. By Hobart M. Smith. Pp. 85-89.
               August 15, 1946.

            3. The tadpoles of Bufo cognatus Say. By Hobart M. Smith.
               Pp. 93-96, 1 figure in text. August 15, 1946.

            4. Hybridization between two species of garter snakes.
               By Hobart M. Smith. Pp. 97-100. August 15, 1946.

            5. Selected records of reptiles and amphibians from Kansas.
               By John Breukelman and Hobart M. Smith. Pp. 101-112.
               August 15, 1946.

            6. Kyphosis and other variations in soft-shelled turtles.
               By Hobart M. Smith. Pp. 117-124, 3 figures in text.
               July 7, 1947.

            7. Natural history of the prairie vole (Mammalian Genus
               Microtus). By E. W. Jameson, Jr. Pp. 125-151, 4 figures
               in text. October 6, 1947.

            8. The postnatal development of two broods of great horned owls
               (Bubo virginianus). By Donald F. Hoffmeister and Henry W.
               Setzer. Pp. 157-173, 5 figures in text. October 6, 1947.

            9. Additions to the list of the birds of Louisiana. By George
               H. Lowery, Jr. Pp. 177-192. November 7, 1947.

           10. A check-list of the birds of Idaho. By M. Dale Arvey.
               Pp. 193-216. November 29, 1947.

           11. Subspeciation in pocket gophers of Kansas. By Bernardo
               Villa-R. and E. Raymond Hall. Pp. 217-236, 2 figures in
               text. November 29, 1947.

           12. A new bat (Genus Myotis) from Mexico. By Walter W. Dalquest
               and E. Raymond Hall. Pp. 237-244, 6 figures in text.
               December 10, 1947.

           13. Tadarida femorosacca (Merriam) in Tamaulipas, Mexico. By
               Walter W. Dalquest and E. Raymond Hall. Pp. 245-248,
               1 figure in text. December 10, 1947.

           14. A new pocket gopher (Thomomys) and a new spiny pocket mouse
               (Liomys) from Michoacán, Mexico. By E. Raymond Hall and
               Bernardo Villa-R. Pp. 249-256, 6 figures in text.
               July 26, 1948.

           15. A new hylid frog from eastern Mexico. By Edward H. Taylor.
               Pp. 257-264, 1 figure in text. August 16, 1948.

           16. A new extinct emydid turtle from the Lower Pliocene of
               Oklahoma. By Edwin C. Galbreath. Pp. 265-280, 1 plate.
               August 16, 1948.

           17. Pliocene and Pleistocene records of fossil turtles from
               western Kansas and Oklahoma. By Edwin C. Galbreath.
               Pp. 281-284. August 16, 1948.

           18. A new species of heteromyid rodent from the Middle Oligocene
               of northeastern Colorado with remarks on the skull. By Edwin
               C. Galbreath. Pp. 285-300, 2 plates. August 16, 1948.

           19. Speciation in the Brazilian spiny rats (Genus Proechimys,.
               Family Echimyidae) By João Moojen. Pp. 301-406, 140 figures
               in text. December 10, 1948.

           20. Three new beavers from Utah. By Stephen D. Durrant and
               Harold S. Crane. Pp. 407-417, 7 figures in text.
               December 24, 1948.

           21. Two new meadow mice from Michoacán, Mexico. By E. Raymond
               Hall. Pp. 423-427, 6 figures in text. December 24, 1948.

           22. An annotated check list of the mammals of Michoacán, Mexico.
               By E. Raymond Hall and Bernardo Villa-R. Pp. 431-472,
               2 plates, 1 figure in text. December 27, 1949.

           23. Subspeciation in the kangaroo rat, Dipodomys ordii. By Henry
               W. Setzer. Pp. 473-573, 27 figures in text, 7 tables.
               December 27, 1949.

           24. Geographic range of the hooded skunk, Mephitis macroura,
               of a new subspecies from Mexico. By E. Raymond Hall and
               Walter W. Dalquest. Pp. 575-580, 1 figure in text.
               January 20, 1950.

           25. Pipistrellus cinnamomeus Miller 1902 referred to the Genus
               Myotis. By E. Raymond Hall and Walter W. Dalquest.
               Pp. 581-590, 5 figures in text. January 20, 1950.

           26. A synopsis of the American bats of the Genus Pipistrellus.
               By E. Raymond Hall and Walter W. Dalquest. Pp. 591-602,
               1 figure in text. January 20, 1950.

           Index. Pp. 605-638.

  *Vol. 2. (Complete) Mammals of Washington. By Walter W. Dalquest.
               Pp. 1-444, 140 figures in text. April 9, 1948.

   Vol. 3. *1. The avifauna of Micronesia, its origin, evolution, and
               distribution. By Rollin H. Baker. Pp. 1-359, 16 figures
               in text. June 12, 1951.

           *2. A quantitative study of the nocturnal migration of birds.
               By George H. Lowery, Jr. Pp. 361-472, 47 figures in text.
               June 29, 1951.

            3. Phylogeny of the waxwings and allied birds. By M. Dale
               Arvey. Pp. 473-530, 49 figures in text, 13 tables.
               October 10, 1951.

            4. Birds from the state of Veracruz, Mexico. By George H.
               Lowery, Jr. and Walter W. Dalquest. Pp. 531-649,
               7 figures in text, 2 tables. October 10, 1951.

           Index. Pp. 651-681.

  *Vol. 4. (Complete) American weasels. By E. Raymond Hall. Pp. 1-466,
               41 plates, 31 figures in text. December 27, 1951.

   Vol. 5.  1. Preliminary survey of a Paleocene faunule from the Angels
               Peak area, New Mexico. By Robert W. Wilson. Pp. 1-11,
               1 figure in text. February 24, 1951.

            2. Two new moles (Genus Scalopus) from Mexico and Texas.
               By Rollin H. Baker. Pp. 17-24. February 28, 1951.

            3. Two new pocket gophers from Wyoming and Colorado.
               By E. Raymond Hall and H. Gordon Montague. Pp. 25-32.
               February 28, 1951.

            4. Mammals obtained by Dr. Curt von Wedel from the barrier
               beach of Tamaulipas, Mexico. By E. Raymond Hall. Pp. 33-47,
               1 figure in text. October 1, 1951.

            5. Comments on the taxonomy and geographic distribution of
               some North American rabbits. By E. Raymond Hall and Keith
               R. Kelson. Pp. 49-58. October 1, 1951.

            6. Two new subspecies of Thomomys bottae from New Mexico and
               Colorado. By Keith R. Kelson. Pp. 59-71, 1 figure in text.
               October 1, 1951.

            7. A new subspecies of Microtus montanus from Montana and
               comments on Microtus canicaudus Miller. By E. Raymond Hall
               and Keith R. Kelson. Pp. 73-79. October 1, 1951.

            8. A new pocket gopher (Genus Thomomys) from eastern Colorado.
               By E. Raymond Hall. Pp. 81-85. October 1, 1951.

            9. Mammals taken along the Alaskan Highway. By Rollin H. Baker.
               Pp. 87-117, 1 figure in text. November 28, 1951.

          *10. A synopsis of the North American Lagomorpha. By E. Raymond
               Hall. Pp. 119-202, 68 figures in text. December 15, 1951.

           11. A new pocket mouse (Genus Perognathus) from Kansas.
               By E. Lendell Cockrum. Pp. 203-206. December 15, 1951.

           12. Mammals from Tamaulipas, Mexico. By Rollin H. Baker.
               Pp. 207-218. December 15, 1951.

           13. A new pocket gopher (Genus Thomomys) from Wyoming and
               Colorado. By E. Raymond Hall. Pp. 219-222.
               December 15, 1951.

           14. A new name for the Mexican red bat. By E. Raymond Hall.
               Pp. 223-226. December 15, 1951.

           15. Taxonomic notes on Mexican bats of the Genus Rhogeëssa.
               By E. Raymond Hall. Pp. 227-232. April 10, 1952.

           16. Comments on the taxonomy and geographic distribution of some
               North American woodrats (Genus Neotoma). By Keith R. Kelson.
               Pp. 233-242. April 10, 1952.

           17. The subspecies of the Mexican red-bellied squirrel, Sciurus
               aureogaster. By Keith R. Kelson. Pp. 243-250, 1 figure in
               text. April 10, 1952.

           18. Geographic range of Peromyscus melanophrys, with description
               of new subspecies. By Rollin H. Baker. Pp. 251-258,
               1 figure in text. May 10, 1952.

           19. A new chipmunk (Genus Eutamias) from the Black Hills.
               By John A. White. Pp. 259-262. April 10, 1952.

           20. A new piñon mouse (Peromyscus truei) from Durango, Mexico.
               By Robert B. Finley, Jr. Pp. 263-267. May 23, 1952.

           21. An annotated check-list of Nebraskan bats. By Olin L. Webb
               and J. Knox Jones, Jr. Pp. 269-279. May 31, 1952.

           22. Geographic variation in red-backed mice (Genus
               Clethrionomys) of the southern Rocky Mountain region.
               By E. Lendell Cockrum and Kenneth L. Fitch. Pp. 281-292,
               1 figure in text. November 15, 1952.

           23. Comments on the taxonomy and geographic distribution of
               North American microtines. By E. Raymond Hall and E. Lendell
               Cockrum. Pp. 293-312. November 17, 1952.

           24. The subspecific status of two Central American sloths.
               By E. Raymond Hall and Keith R. Kelson. Pp. 313-337.
               November 21, 1952.

           25. Comments on the taxonomy and geographic distribution of some
               North American marsupials, insectivores, and carnivores.
               By E. Raymond Hall and Keith R. Kelson. Pp. 319-341.
               December 5, 1952.

           26. Comments on the taxonomy and geographic distribution of some
               North American rodents. By E. Raymond Hall and Keith R.
               Kelson. Pp. 343-371. December 15, 1952.

           27. A synopsis of the North American microtine rodents.
               By E. Raymond Hall and E. Lendell Cockrum. Pp. 373-498,
               149 figures in text. January 15, 1953.

           28. The pocket gophers (Genus Thomomys) of Coahuila, Mexico.
               By Rollin H. Baker. Pp. 499-514, 1 figure in text.
               June 1, 1953.

           29. Geographic distribution of the pocket mouse, Perognathus
               fasciatus. By J. Knox Jones, Jr. Pp. 515-526, 7 figures in
               text. August 1, 1953.

           30. A new subspecies of wood rat (Neotoma mexicana) from
               Colorado. By Robert B. Finley, Jr. Pp. 527-534, 2 figures
               in text. August 15, 1953.

           31. Four new pocket gophers of the genus Cratogeomys from
               Jalisco, Mexico. By Robert J. Russell. Pp. 535-542.
               October 15, 1953.

           32. Genera and subgenera of chipmunks. By John A. White.
               Pp. 543-561, 12 figures in text. December 1, 1953.

           33. Taxonomy of the chipmunks, Eutamias quadrivittatus and
               Eutamias umbrinus By John A. White. Pp. 563-582, 6 figures
               in text. December 1, 1953.

           34. Geographic distribution and taxonomy of the chipmunks of
               Wyoming. By John A. White. Pp. 584-610, 3 figures in text.
               December 1, 1953.

           35. The baculum of the chipmunks of western North America.
               By John A. White. Pp. 611-631, 19 figures in text.
               December 1, 1953.

           36. Pleistocene Soricidae from San Josecito Cave, Nuevo Leon,
               Mexico. By James S. Findley. Pp. 633-639. December 1, 1953.

           37. Seventeen species of bats recorded from Barro Colorado
               Island, Panama Canal Zone. By E. Raymond Hall and William
               B. Jackson. Pp. 641-646. December 1, 1953.

           Index. Pp. 647-676.

  *Vol. 6. (Complete) Mammals of Utah, _taxonomy and distribution._
               By Stephen D. Durrant. Pp. 1-549, 91 figures in text,
               30 tables. August 10, 1952.

   Vol. 7. *1. Mammals of Kansas. By E. Lendell Cockrum. Pp. 1-303,
               73 figures in text, 37 tables. August 25, 1952.

            2. Ecology of the opossum on a natural area in northeastern
               Kansas. By Henry S. Fitch and Lewis L. Sandidge.
               Pp. 305-338, 5 figures in text. August 24, 1953.

            3. The silky pocket mice (Perognathus flavus) of Mexico.
               By Rollin H. Baker. Pp. 339-347, 1 figure in text.
               February 15, 1954.

            4. North American jumping mice (Genus Zapus). By Philip H.
               Krutzsch. Pp. 349-472, 47 figures in text, 4 tables.
               April 21, 1954.

           More numbers will appear in Volume 7.


       *       *       *       *       *

Transcriber's Notes

All obvious typos corrected. In Table 5 on the Swan Lake row, the Mean
value for the Palatal length was corrected to 10.1 mm as there were only
two values averaged (10.0 and 10.2). Abbreviation inconsistencies for
mountain(s) were retained. Where a publication name contains an
alternate spelling of a word, it was retained (example, Athabaska). The
author Bernardo Villa-Ramirez is sometimes listed with the hyphen and
sometimes without. For consistancy, they were standardized with a
hyphen.


Typographical Corrections

  Page(s)   Correction
  ========= ======================
  380       dention => dentition
  412, 414  Eldorado => El Dorado
  417       Sitkine River, at Glenoria => Stikine River, at Glenora