THE
                       CONCHOLOGIST’S FIRST BOOK:
                                   A
                                 SYSTEM
                                   OF
                         TESTACEOUS MALACOLOGY,
               Arranged expressly for the use of Schools,
                                IN WHICH
      THE ANIMALS, ACCORDING TO CUVIER, ARE GIVEN WITH THE SHELLS,
                  A GREAT NUMBER OF NEW SPECIES ADDED,
  AND THE WHOLE BROUGHT UP, AS ACCURATELY AS POSSIBLE, TO THE PRESENT
                       CONDITION OF THE SCIENCE.


                            BY EDGAR A. POE.


                            SECOND EDITION.

   WITH ILLUSTRATIONS OF TWO HUNDRED AND FIFTEEN SHELLS, PRESENTING A
                      CORRECT TYPE OF EACH GENUS.


                             PHILADELPHIA:

                      PUBLISHED FOR THE AUTHOR, BY
                   HASWELL, BARRINGTON, AND HASWELL,
    AND FOR SALE BY THE PRINCIPAL BOOKSELLERS IN THE UNITED STATES.

                                 1840.




Entered according to act of Congress, in the year 1839, by EDGAR A. POE,
in the clerk’s office for the eastern district of Pennsylvania.

                               Printed by
                   Haswell, Barrington, and Haswell.




                                PREFACE
                         TO THE FIRST EDITION.


The term “_Malacology_,” an abbreviation of “_Malacozoology_,” from the
Greek μαλακος, _soft_, ζωον, _an animal_, and λογος, _a discourse_, was
first employed by the French naturalist De Blainville to designate an
important division of Natural History, in which the leading feature of
the animals discussed was the _softness_ of the flesh, or, to speak with
greater accuracy, of the general envelop. This division comprehends not
only the _Mollusca_, but also the _Testacea_ of Aristotle and of Pliny,
and, of course, had reference to molluscous animals in general—of which
the greater portion have shells.

A treatise concerning the shells, exclusively, of this greater portion,
is termed, in accordance with general usage, a Treatise upon Conchology
or Conchyliology; although the word is somewhat improperly applied, as
the Greek _conchylion_, from which it is derived, embraces in its
signification both the animal and shell. Ostracology would have been
more definite.

The common works upon this subject, however, will appear to every person
of science very essentially defective, inasmuch as the _relation_ of the
animal and shell, with their dependence upon each other, is a radically
important consideration in the examination of either. Neither, in the
attempt to obviate this difficulty, is a work upon Malacology at large
necessarily included. Shells, it is true, form, and, for many obvious
reasons, will continue to form, the subject of chief interest, whether
with regard to the school or the cabinet; still there is no good reason
why a book upon _Conchology_ (using the common term) may not be
malacological as far as it proceeds.

In this view of the subject the present little work is offered to the
public. Beyond the ruling feature—that of giving an anatomical account
of each animal, together with a description of the shell which it
inhabits,—I have aimed at little more than accuracy and simplicity, as
far as the latter quality can be thought consistent with the rigid
exactions of science.

No attention has been given to the mere _History_ of the subject; it is
conceived that any disquisition on this head would more properly
appertain to works of ultimate research, than to one whose sole
intention is to make the pupil acquainted, in as tangible a form as
possible, with _results_. To afford, at a cheap rate, a concise, yet
sufficiently comprehensive, and especially a well illustrated
school-book, has been the principal design.

In conclusion, I have only to acknowledge my great indebtedness to the
valuable public labors, as well as private assistance, of Mr. Isaac Lea,
of Philadelphia. To Mr. Thomas Wyatt, and his late excellent _Manual of
Conchology_, I am also under many obligations. No better work, perhaps,
could be put into the hands of the student as a secondary text book. Its
beautiful and perfectly well-coloured illustrations afford an aid in the
collection of a cabinet scarcely to be met with elsewhere.

                                                                E. A. P.




                                PREFACE
                         TO THE SECOND EDITION.


In issuing a second edition of this “Conchology,” in so very brief a
period since the publication of the first large impression, the author
has little more to do than to express the high pleasure with which he
has seen his labors well received. The success of the work has been
decided; and the entire design has been accomplished in its general
introduction into schools.

Many important alterations and additions are now made; errors of the
press carefully corrected; many more recently discovered American
species added; and the work, upon the whole, is rendered more worthy the
public approbation.

                                                                E. A. P.




                             INTRODUCTION.


The term “_Conchology_,” in its legitimate usage, is applied to that
department of Natural History which has reference to animals with
testaceous covering or shells. It is not unfrequently confounded with
_Crustaceology_, but the distinction is obvious and radical, lying not
more in the composition of the animal’s habitation, than in the
organization of the animal itself. This latter, in the _Crustacea_, is
of a fibrous nature, and has articulated limbs; the shell, strictly
adapted to the members, covers the creature like a coat of mail, is
produced at one elaboration, is cast or thrown aside periodically, and,
again at one elaboration, renewed; it is moreover composed of the animal
matter with phosphate of lime. In the _Testacea_, on the contrary, the
inhabitant is of a simple and soft texture, without bones, and is
attached to its domicil by a certain adhesive muscular force; this
domicil, too, is a permanent one, and is increased, from time to time,
by gradual additions on the part of the tenant; while the entire shell,
which is distributed in layers, or strata, is a combination of carbonate
of lime, with a very small portion of gelatinous matter. Such animals,
then, with such shells, form, alone, the subject of a proper
“Conchology.”

Writers have not been wanting to decry this study as frivolous or
inessential; most unjustly assailing the science itself, on account of
the gross abuses which have now and then arisen from its exclusive and
extravagant pursuit. They have reasoned much after this fashion:—that
Conchology is a folly, because Rumphius was a fool. The _Conus Cedo
Nulli_ has been sold for three hundred guineas; and the naturalist just
mentioned gave a thousand pounds sterling for one of the first
discovered specimens of the _Venus Dione_ (of Linnæus). But there have
been men in all ages who have carried to an absurd, and even pernicious
extreme, pursuits the most ennobling and praiseworthy.

To an upright and well regulated mind, there is no portion of the works
of the Creator, coming within its cognizance, which will not afford
material for attentive and pleasurable investigation; and, so far from
admitting the venerable error even now partially existing to the
discredit of Conchology, we should not hesitate to acknowledge, that
while few branches of Natural History are of more direct, _very few_ are
of more adventitious importance.

Testaceous animals form the principal subsistence of an immense number
of savage nations, inhabitants of the sea-board. On the coast of Western
Africa, of Chili, of New Holland, and in the clustered and populous
islands of the Southern seas, how vast an item is the apparently
unimportant shell-fish in the wealth and happiness of man! In more
civilized countries it often supplies the table with a delicate luxury.
Nor must we forget the services of the _pinna_ with its web, nor of the
_purpura_ with its brilliant and once valuable dye, nor omit to speak of
the pearl-oyster, with the radiant nacre, and the gem which it produces,
and the world of industry which it sets in action as minister to the
luxury which it stimulates.

Shells, too, being composed of particles already in natural combination,
have not within them, like flowers and animals, the seed of dissolution.
While the preparation of a specimen for the cabinet is a simple
operation, a conchological collection will yet remain perfect for ages.
These important circumstances being duly considered, in connexion with
the universally acknowledged beauty and variety, both of form and
colour, so strikingly observable in shells, it is a matter for neither
wonder nor regret that these magnificent _exuviæ_, even regarded merely
as such, should have attracted, in a very exclusive degree, the
attention and the admiration of the naturalist. The study of Conchology,
however, when legitimately directed, and when regarding these _exuviæ_
in their natural point of view, as the habitations, wonderfully
constructed, of an immensely numerous and vastly important branch of the
animal creation, will lead the mind of the investigator through paths
hitherto but imperfectly trodden, to many novel contemplations of
Almighty Beneficence and Design.

But it is, beyond all doubt, in a geological point of view that
Conchology offers the most of interest to the student; and here, by
reference to the fair pages of a profound and mighty knowledge to which
it has pointed out the searcher after truth, are triumphantly refuted
all charges brought against it of insignificance or frivolity.

“In fine, the relations of the mollusca,” says De Blainville, “with the
mineral kingdom, and consequently with the mass of the earth which they
contribute to form, are not devoid of interest, for without seeking here
to resolve the physiological question—whether the conchyliferous
mollusca borrow of the inorganic kingdom the calcareous matter which
composes their shells, or whether they form it of themselves, it is
still certain that they produce, at least, changes upon the surface of
the earth by accumulating this material in some places more than in
others, and in consequence that they alter the physiognomy of the
superficial structure of the globe, the study of which constitutes
geognosy.”

“By this,” says Parkinson, “we are taught that innumerable beings have
lived, of which not one of the same kind does any longer exist—that
immense beds composed of the spoils of these animals, extending for many
miles under ground, are met with in many parts of the globe—that
enormous chains of mountains, which seem to load the surface of the
earth, are vast monuments, in which these remains of former ages are
entombed—that, though lying thus crushed together, in a rude and
confused mass, they are hourly suffering those changes, by which, after
thousands of years, they become the chief constituent parts of gems, the
limestone which forms the humble cottage of the peasant, or the marble
which adorns the splendid palace of the prince.” Fossil, wood, coral,
and shells, are, indeed, as Bergman very forcibly observes, the only
true remaining “medals of Creation.”




                  EXPLANATION OF THE PARTS OF SHELLS.


                              MULTIVALVE.

A MULTIVALVE shell is composed of more parts than two. Every part of a
shell which is connected by a cartilage, ligament, hinge, or tooth, is
called a valve of such shell; thus, the Chitons have eight transverse,
broad, but very short valves, placed on the back of the animal, and
inserted at their sides into a marginal tough ligament. Plate I. fig.
11, _a a a_.

_Operculum_ consists of four small valves on the summit of the Lepas,
which shut up the superior orifice; it is in a certain degree
stationary, and different from the operculum of univalve shells, which
will hereafter be described. Plate I. fig. 1, A. Fig. 9 represents a
profile view of the operculum removed from its place, _a_ the front
valves, _b_ the back valves. Fig. 10 a front view of the operculum.

_Base_ is that part of the shell by which it is fixed to rocks and other
bodies. Plate I. fig. 1 and 2, B B B.—H is a piece of stone to which the
base is fixed, and G a piece of wood to which the shells of this section
are generally attached.

_Ligament_ is the membranous or tendinous substance by which the valves
or parts of the shell are attached. Some multivalve shells are connected
by the parts of one valve locking into another. Plate I. fig. 2, D D D.
The ligaments vary considerably in their texture, being scaly, prickly,
smooth, or punctated.

_Ridges_ are certain convexities in many of the Lepas tribe, sometimes
longitudinal and sometimes transverse. Plate I. fig. 1, F F.

_Peduncle._ A sort of stem by which the shells of the Anatifera are
attached to wood, &c. It is a membranaceous substance, similar to a
bladder but materially thinner, and filled with a liquid which evidently
affords nourishment to the animal. Plate I. fig. 2, C C; the peduncle is
usually affixed to a piece of wood as represented at G.

_Feelers_ are those crenated arms, evolved from the side of the
Anatifera. While the animal is in the water it continually moves its
feelers, evidently for the purpose of entangling minute marine insects,
as food. Plate I. fig. 2, E E.

_Accessory valves_ are small plates which cover the apex at the hinge of
the Pholades, or are situated below the hinge. Plate I. fig. 3, _a_.

_Margin._ A fleshy border in which the valves are attached in the genus
Chiton. Plate I. fig. 11, _b b_.


                                BIVALVE.

Bivalve shells consist of two parts or valves, connected by a cartilage,
and a hinge which is generally composed of teeth; those of the one valve
locking into a cavity in the other.

The valves of some bivalve shells are formed exactly alike, and others
are very different; the one being smooth, the other rugose; one flat and
another convex; and often one is shorter than the other.

The shells of the Mya, Solen, Tellina, Venus, and others, have in
general both valves alike, while those of the Spondylus, Ostrea, and
Anomia, have in general dissimilar valves. The first of these kinds are
called equivalve, and the latter inequivalve.

_Equilateral_ shells, are those whose sides are alike, as in the shells
of the genus Pecten. Plate II. fig. 2, and Plate VII. fig. 14. This is
also exemplified in the Pectunclus.

_Inequilateral valves_ are shells whose sides are unequal; and of
different shapes, as in the Mactra, Donax, &c.

_Summit_ is the most elevated point of that part of the shell in which
the hinge is placed. Plate I. fig. 4, _i k_.

In naming this the summit we do not follow the axiom of Linnæus, but
because we consider it more properly the summit of the shell than the
opposite extremity.

_Base_ is the reverse of the above, or that part of the shell
immediately opposite the summit. Plate I. fig. 6 and 7, _d d_.

_Sides_, the right and left parts of the valves. Plate I. fig. 6, _c_.

_Posterior slope_ is that part of the shell in which the ligament is
situated. In viewing the posterior slope in front, the beaks of the
shell retire from view. Plate I. fig. 4, _i_.

_Anterior slope_, that part of the shell opposite the posterior slope;
in viewing it in front, the beaks point to the observer. Plate I. fig.
4, _k_.

_Disk_, the convex centre of a valve, or most prominent part of the
valve, suppose it with its inside lying undermost. Plate I. fig. 4, _o_.

_Inside_, the concave part of a valve. Plate IV. fig. 6, _m_.

_Muscular impression_ is the impression left on the inside of the
valves, by the adhering muscles of the animal. It differs in most
shells, according to the shape of the animal, as semi-ovate, round,
lunate, elongated, &c. As a specific distinction, it is often of great
use; being, with a very few exceptions, alike in shells of the same
species. Some shells have only one cicatrix, as the Edible Oyster and
Mytilus; others have two, and some few more; the Tellina for example.
Plate I. fig. 6 and 8, _e e e e_.

_Lunule._ The lunated depressions, situated in the anterior and
posterior slopes. In different species of Venus they are prominent
characteristic marks, often of much service in ascertaining a species.
Plate I. fig. 4, _b b_.

_Ligament perforation._ The circular aperture, or perforation through
which the ligament passes; by which the animal of the Anomia attaches
itself to stones and other marine extraneous bodies, it is in general
situated in the flat valve, though there are a few exceptions to the
contrary. Plate I. fig. 7, _m_.

_Hinge_ is the point at which bivalve shells are united; it is formed by
the teeth of one valve inserting themselves between those of the other,
or by the teeth of one valve fitting into the cavities or sockets of the
opposite one.

It is on the peculiar construction of the _hinge_ that the generic
character of bivalve shells is principally founded, together with the
general contour of the shell. Plate II. fig. 1 and 3, _q q q_.

_Teeth of the hinge._ Upon the number and relative situation of the
teeth principally depend the specific distinctions; they are of various
forms, and very differently placed; some are single and large, others
numerous and small, orbicular, spatuliform, laminated, &c. Some hinges
have no visible teeth, and are termed _inarticulate_.—When a primary
tooth has a groove or hollow in its centre, it is called complicated.
Plate IV. Fig. 6, _e_; those with few teeth are termed _articulate_.
Plate IV. fig. 1 and 12; and those with many teeth _multiarticulate_.
Plate IV. fig. 2, 3, 4, &c. Plate I. fig. 6, and 8, _g g g g_.

_Primary teeth_ are those teeth in general situated in the centre of the
hinge, and are for the most part broad, large, and distinct, often
elevated; and in general are inserted in a cavity in the opposite valve.
They however differ very much in some shells, but may easily be
distinguished. Plate IV. fig. 1, 3, and 7, _a a a a a_. These are also
termed the Cardinal Teeth.

_Lateral Teeth_, Plate IV. fig. 10, are teeth which diverge from the
Umbo, and are in general long and flat, often double and divided by a
groove or hollow. Plate IV. fig. 2, 4, 6, and 7. _b b b b_.

_Double Teeth_, Plate IV. fig. 1, _c c_.

_Incurved Teeth_ are those which are bent round, as in the single tooth
of the Solen. Plate IV. fig. 8, _f f_.

_Recurved Teeth_, are those which are bent backwards, as in the hinge of
the Panopea and Spondylus.

_Middle Teeth_, Plate IV. fig. 4, _d d_. These are also termed Cardinal
Teeth.

_Numerous Teeth_, are those small upright teeth, set in rows, of which
the hinges of all the species of the genus Arca are formed. Plate IV.
fig. 10, _k k_.

_Cavity of the Hinge._ The hollow depression in which the ligament of
the Ostrea is situated, generally of a triangular form. Plate IV. fig.
11, _g_.

_Ligament_ of the Hinge, or cartilage, is that flexible fibrous
substance by which the valves are united, and the hinges kept in their
proper places; generally situated under the beaks of the shell. Plate
II. fig. 1, 3, and 4, _l l l_; Plate IV. fig. 3, _n_.

_Beak_ is the extreme point of the summit of bivalves, which in many
species turns spirally downwards or to the one side, as in some species
of Venus, &c. From this circumstance it is seldom the highest part of
the shell. Plate II. fig. 5, _r r_.

_Seam._ When the valves are closed, the line of separation between them
is so called. Plate II. fig. 6, _t t_.

_Umbo._ That part situated immediately under the _beak_. Plate I. fig.
6, _w_; and Plate II. fig. 4, _w_.

_Ears._ The processes on each side of the beak, in most species of that
division of Ostrea, called Pecten; some have one ear very large, and the
other small; and some are scarcely observable on one side. Pl. II. fig.
2, _h h_.

_Superior Ear._ Plate IV. fig. 11, _h_.

_Inferior Ear._ Do. do. _i_.

_Margin._ The extreme edge of the whole shell, or the circumference of
either valve, all round. Plate I. fig. 4, _p_; and Plate II. fig. 1,
_p_.

_Crenulated margin._ That fine notched edge of shells, which unite into
notches in the opposite valve, as genus Donax. Plate IV. fig. 6, _m m_.

_Striæ_ are fine thread-like lines, generally on the exterior surface of
shells, and are sometimes both longitudinal and transverse. When the
striæ of shells appear indistinct, as if worn out, it is termed
_obsolete striæ_. In some instances the insides of shells are striated;
for example, the Fasciolaria Tulipa. The character of the striæ is often
of much use in distinguishing species. Plate II. fig 2, _f_.

_Right Valve_ is that valve which, when viewed with the inside
uppermost, has the anterior slope pointing to the right hand. Plate I.
fig. 8; and Plate IV. figs. 5 and 6, _B_.

_Left Valve._ The opposite of the above; the anterior slope points to
the left hand, when viewed from the inside. Plate IV. figs. 3, 6, 7, 9,
&c.

_Length of the Shell_ is taken from the ligament, or the beak, to the
opposite margin. For example, Mytilus: it is longer than it is broad,
and the Solens are broader than long. Plate I. fig. 5, _u u_; and Plate
II. fig. 4, _v v_.

_Breadth_ is measured from the most extreme edge of the anterior and
posterior slopes, being in a contrary direction from its length. Many
shells are _broader than long_, such as most of the Myæ, Solenæ,
Tellinæ, &c.; and the Mytilus, Ostrea, Pinna, &c., are in general longer
than broad. Plate I. fig. 5, _v v_. Plate II. fig. 4, _v v_.

_Byssus_, or _beard_, is an appendage composed of filaments of a silky
texture, by which some of the Bivalves fasten themselves to their beds,
such as the Mytilus, Pinnæ, &c. Plate II. fig. 6, _s_.


                               UNIVALVE.

The shells called univalve, or those composed of one part only, are far
more numerous than the two preceding, both in genera and species; and it
requires a considerable degree of attention to discriminate many of the
_species_, as they run into each other so much; and they are divested of
the strong and distinct character afforded by the teeth of bivalves;
besides many of the species there are several varieties.

In the examination of shells of this order, the general contour or
outline of the whole shell is the first particular to be attended to, as
this leads to those distinctions necessary in the definition of simple,
spiral, or turbinated shells, Univalves with a regular spire, and those
without a regular spire. The genera of this order are formed principally
from the shape of the aperture, taken in conjunction with the general
shape of the shell; from the spire being lengthened or depressed, being
with or without a canal, the length of the beak and its direction,
together with the particular form of the outer lip: the colour of shells
only serves as a specific distinction, and cannot in this respect, in
all cases, be depended upon, although in others it is an unvarying test.
The particular manner in which the spots are disposed frequently
characterises species.

_Apex._ The summit, tip, or highest part of the spire. Plate II. figs.
7, 8, 9, _A A A_.

_Base_ is the opposite extremity from the apex, or tip of the spire. In
shells with a beak it implies the tip of such beak; Plate II. fig. 11,
_B_. In shells without a beak it is understood to be the lower part, as
before-mentioned, opposite the apex; Plate II. figs. 8 and 9, _B B_. In
the Patella and some others, the base of the shell is that part on which
it rests when it is laid on its mouth. In the Dentalium and Teredo it is
the wider end.

_Body_ of the shell is the first or lower whorl of the spire, in which
the aperture is situated, and is in general longer than the remaining
whorls. Plate II. figs. 10 and 12, _F F_; and Plate III. figs. 7 and 9,
_F F_.

_Front_ of the shell is that side where the aperture is situated. Plate
II. fig. 7, _I_; and Plate III. fig. 8, _I_.

_Back_ is the opposite side to that in which the aperture is placed or
turned directly from the observer. Plate III. figs. 5 and 10, _G G_.

The _venter_, or belly, is the most prominent part of the lower whorl or
body, generally situated in the vicinity of the lip over the aperture;
and formed by the convexity of the aperture. It is in general only made
use of in describing shells whose body is large in proportion to the
size of the spire. Plate III. figs. 5 and 10, _H H_.

_Sides._ The extreme edges of the shell, when viewed either in front or
from the back. Plate II. fig. 11, _K K K K K K K K_. Right side is, when
the shell is viewed in front that side next the observer’s left hand.
Left side, the side with the aperture in it.

_Aperture_, or mouth, is that part of the lower whorl or body by which
the animal protrudes itself. This is one of the principal generic
distinctions of Univalve shells, and differs very much in shape; some
apertures being rounded, others semilunar, angular, &c. Plate II. figs.
9 and 11, _C C_; and Plate III. figs. 1, 3, and 14, _C C C_. Some
apertures have a canal at their base, and others are devoid of it. In
various genera it extends the whole length of the shell, as in the
Cypræa, and some of the Cones with depressed spires. This in several
individuals is either entirely open, or is closed by an operculum or
lid, which is usually affixed to the foot of the animal.

_Canal_, or gutter, is the inside of the elongations of the aperture, or
both lips of the shell of those species with a beak, in which it forms a
concave channel or gutter, running from its commencement in the aperture
to the extremity or base. Plate II. figs. 10 and 11, _Q Q_. Plate III.
fig. 8, _Q_. Some species are furnished with two canals, one situated at
the junction of the outer lip and body, as in the Murex.

_Beak_ is that lengthened process in which the canal is situate; it
commences a little higher up, on the outside, than the insertion of the
canal in the inside, which is always distinctly marked by the line of
the aperture. Plate II. fig. 11, _p_. This process is not so conspicuous
in some of the species of Voluta, but is more marked in the genera
Murex, Fusus, Pyrula, &c.

_Pillar_, or _columella_, is that process which runs through the centre
of the shell in the inside from the base to the apex in most univalve
shells, and appears to be the support of the spire: and, indeed, seems
to form that part of the shell: it is in general grooved or folded; but,
as it is situated in the interior of the shell, a minute description is
unnecessary. Plate II. figs. 10 and 12, _M M M M M_; and Plate III. fig.
9, _M M M_. The internal edge of its base is frequently described as
having plaits, &c.

_Plaited Columella_ are those folds, or plaits, which are the
distinguishing characteristic of the Volutæ and other genera. Plate II.
fig. 7, _z_.

_Pillar Lip_ is a continuation of the glossy process with which the
aperture is lined, and expanded on the columella. Plate III. figures 7
and 8, _O O_. This is termed the inner lip by some authors.

_Outer Lip._ The expansion, or continuation of the body of the shell on
the left margin of the aperture, and is also lined with the glossy
process of the aperture. Plate II. fig. 7, _N_; and Plate III. fig. 8,
_N N N_. The latter is an example of the alated or winged shells.

_Operculum_, or lid. This is only an appendage to the turbinated or
spiral shells affixed to the foot of the animal, sometimes of a
testaceous, in others of a horny or cartilaginous substance. It acts as
a door or lid, and is calculated for the protection of the animal, when
it retires within its dwelling, from the intrusion of its enemies, and
adapted to the shape of the aperture, which it closes nicely up: as
exemplified in the operculum of the Turbo, and is of a hard, stony
appearance. Plate III. fig. 4.

_Spire_ consists of all the whorls of the shell, except the lower one,
which, as before observed, is termed the body of the shell. Plate II.
fig. 12, _D_; and Plate III. figures 7 and 8, _D D_.

The spire is a prominent feature of the Univalve; and upon its being
elevated, depressed, &c., depends much of the generic and specific
definition. Adanson, in his ‘Natural History of Senegal,’ says that the
external character of the spire varies according to the plane they turn
upon, which, he observes, is either horizontal, cylindrical, conic, or
ovoid. At the same time, he admits that there are a great many
intermediate forms which cannot properly be defined.

It must be remembered that many of the young shells have not the same
number of wreaths as the adults; from which it would appear, that the
part of the animal nearest the apex never increases in size. The number
of wreaths cannot, at all times, be depended upon. A full grown shell
may, however, be known from the outer lip, which has generally an
unfinished appearance in young shells. Indeed, in all the land and fresh
water shells it is a distinct criterion, as they are never complete in
the form of the outer lip till full grown.

_Whorl_ is one of the wreaths or volutions of the shell. Plate II. fig.
8, _L_; and Plate III. fig. 10, _L_.

_Depressed Spire_ is when the spire is very flat, as in the shells of
the genus Planorbis, &c. Pl. II. fig. 12, _D_; and Pl. III. fig. 5, _S_.

A flat shell is figured in Plate III. fig. 14.

_Involuted Spire_, those shells which have their whorls, or wreaths,
concealed in the inside of the first whorl or body, as in some of the
Nautili and Cypræa.

_Suture of the Spire_, or whorls, is a fine spiral line, which separates
the wreaths or whorls from each other; it is sometimes crenulated,
undulated, or sulcated, and not unfrequently elevated or projecting.
Plate II. fig. 9, _E E_.

_Reversed_, or _Heterostrophe Spire_, is when the volutions of the spire
revolve in the same manner as a common corkscrew, or when the aperture
is placed downwards, the nature of the spire runs upwards from the right
hand to the left, Plate III. fig. 13.

In some of the more depressed species of Helix, or Nautilus, great
attention is requisite in order to ascertain which is really the upper
side of the shell, for it is on that side the spiral turns are to be
taken from the centre or apex; and, in most instances, this is to be
determined by the oblique direction of the aperture to the under part,
where the lip rarely extends so far as on the upper part. In fixed
shells, such as Serpulæ, there is no difficulty, as the side which is
sessile must be considered as the base or under part. Thus, in the
Serpula Lucida the fixed part is sometimes very small, and the mouth
turns spirally upwards, in a contrary direction to the sun; and
therefore must be considered a reversed or heterostrophe shell, the same
as if the volutions nearest the mouth had turned laterally upon the
centre or fixed ones. This shell, indeed, is most frequently found with
regular lateral volutions; and though subject to great variety, with
respect to contortions, it invariably turns the aperture one way.

In some species of Nautilus, however, there can be no rule to ascertain
whether the shells are dextral or sinistral; for when the aperture is
exactly central, the lip embraces the body equally, and the sides of the
shell are similar.

_Chambers_ are the cavities divided by partitions, at regular or
irregular intervals; as in the Spirula. Plate III. fig. 11, _W W W W W_.

In some of the Serpulæ there are also divisions, but they are not
regular as in the Nautili and Spirulæ; and besides, they differ from
them in being devoid of a siphunculus or communication between the
chambers, the animal forms a complete partition, and adds to its shell,
which it would appear to be necessitated to do from its body growing too
large for its abode.

Several of the Patellæ have chambers formed of laminous partitions,
subspiral cells, or processes; these in general lie horizontally, and
are quite open at one end, as in the Patella Testudinaria, the
Crepidula, and Calyptræa.

_Umbilicus_ is in general a circular perforation in the base of the
lower whorl, or body, of many univalve shells. This is common to most of
the Trochi, in some species of which it penetrates from the base to the
apex; widest at the base, and gradually tapering to the top. Plate III.
fig. 1, _u_.

_Sub-umbilicated_ shells are those which have the umbilicus covered in a
greater or less degree by a thin process; which, in some, almost
entirely closes the opening or mouth. This character is most commonly to
be met with among species of Buccinum and Murex.

Shells which have no umbilicus are termed imperforate.

_Siphunculus_ is that small round perforation which forms a
communication between the chambers of the Spirulæ, and penetrates
through the whole spire of the shell. Plate III. fig. 11, _v_.

_Varices_ are transverse ribs which cross the whorls of shells in some
species of Buccinum, Murex, and Tritonia, and exemplified in the
Cassidaria. Varices are formed by the periodical growth of the shells,
these being the margin of the outer lip, to which the animal has
attached its periodical enlargements. In some species they have more the
form of sutures than ribs; this is owing to the margin of the outer lip
being but slightly developed.

_Ribs_ are those longitudinal and transverse protuberances which are in
many of the univalve shells. Plate III. fig. 12, _R R R R_.

_Teeth_ of univalves, or tooth-shaped protuberances, are fine, white
laminæ, or ridges, running spirally backwards, in a parallel direction
to each other; those on the exterior lip may, in most instances, be
traced through the outside of the shell, and are nearly alike in length.
Plate III. fig. 13, _a_.

_Epidermis_ is a skin, or cuticle, covering the exterior surface of
shells, destined by nature to protect their surface from being injured.
It is membranaceous, somewhat similar to the periosteum which covers the
bones of animals. This substance is the production of the animal
inhabiting the shell; it is uniformly observed in some species, and not
at all in others. Shells with a rugged or uneven surface have almost
always this epidermis. In some it is strong, laminated, velvety,
fibrous, or rough, often beset with long hairs, and in others very thin,
smooth, and pellucid, and admits the colours of the shell to shine
through it. In some species it is so dusky that it entirely obscures the
beautiful colouring of the shell beneath. Although many shells are very
beautiful, even with this cuticle on them, they are much more so when it
is removed; but I would by no means advise the collector of shells to
remove it, unless he may have several duplicates of the same species;
and then he may do it by way of variety. It is always preferable,
however, to keep them in a state of nature.

A shell with epidermis is represented in Plate III. fig. _X_; and the
effect of the epidermis removed.

All other protuberances, furrows, &c., will be described at the end of
this work in a Glossary of Terms used in the Science.


                        DESCRIPTION OF PLATE IV.

                       HINGES OF BIVALVE SHELLS.

Fig. 1. Hinge of the Unio pictorum, _a_ Primary tooth, _c c_ double
teeth.

Fig. 2. Hinge of the _Solen_. _b_ Lateral teeth.

Fig. 3. Hinge of the Lucina radula, _a a_ Primary teeth, _n_ cartilage.

Fig. 4. Hinge of the _Cardium_. _b_ Lateral tooth, _d d_ middle teeth,
_l l_ spines.

Fig. 5. Hinge of the Lutraria.

Fig. 6. Inside of both valves of the _Donax trunculus_. _A_ is the left
valve, and _B_ is the right valve, _b_ lateral teeth, _e_ primary
complicated tooth, or cleft in the middle, _m m_ crenulated margin.

Fig. 7. Hinge of the _Venus_, _a a_ Primary teeth.

Fig. 8. Hinge of _Spondylus gæderopus_, _f f_ incurved teeth.

Fig. 9. Hinge of Isocardia Cor.

Fig. 10. Hinge of the Pectunculus, _k k_ numerous small teeth; the
distinguishing characteristic of the Family _Arcacea_.

Fig. 11. Hinge of the Pecten, _g_ cavity of the hinge, _h_ superior ear,
_i_ inferior ear.

Fig. 12. Hinge of _Anomia Ephippium_.




                            CLASSIFICATION.


                                CLASS I.

                               ANNULATA.

                             FOUR FAMILIES.

             Fam.
               1. _Dorsalia._            Two genera.
                    1. Arenicola.          Species        1
                    2. Siliquaria.            „           8

               2. _Maldania._            Two genera.
                    1. Clymene.            Species        1
                    2. Dentalium.             „          21

               3. _Amphitritæa._        Four genera.
                    1. Pectinaria.         Species        2
                    2. Sabellaria.            „           2
                    3. Terebella.             „           4
                    4. Amphitrite             „           7

               4. _Surpulacea._         Five genera.
                    1. Spirorbis.          Species        6
                    2. Serpula.               „          26
                    3. Vermilia.              „           9
                    4. Galeolaria.            „           2
                    5. Magilus.               „           2


                               CLASS II.

                              CIRRHIPEDA.

                              ONE FAMILY.

               1. _Cirrhipeda._          Ten genera.
                    1. Tubicinella.        Species        1
                    2. Coronula.              „           5
                    3. Balanus.               „          30
                    4. Acasta.                „           4
                    5. Creusia.               „           3
                    6. Pyrgoma.               „           1
                    7. Anatifera.             „           6
                    8. Pollicipes.            „           6
                    9. Cineras.               „           1
                   10. Otion.                 „           2


                               CLASS III.

                              CONCHIFERA.

                            TWENTY FAMILIES.

               1. _Tubicola._            Six genera.
                    1. Aspergillum.        Species        4
                    2. Clavagella.            „           4
                    3. Fistulana.             „           4
                    4. Septaria.              „           2
                    5. Teredina.              „           2
                    6. Teredo.                „           3

               2. _Pholadaria._          Two genera.
                    1. Pholas.             Species       18
                    2. Gastrochæna.           „           3

               3. _Solenea._            Four genera.
                    1. Solen.              Species       21
                    2. Panopea.               „           1
                    3. Solecurtus.            „          10
                    4. Glycimeris.            „           2

               4. _Myaria._              Two genera.
                    1. Mya.                Species        8
                    2. Anatina.               „          12

               5. _Mactracea._          Seven genera.
                    1. Lutraria.           Species       14
                    2. Mactra.                „          44
                    3. Crassatella.           „          11
                    4. Erycina.               „           2
                    5. Ungulina.              „           2
                    6. Solemya.               „           4
                    7. Amphidesma.            „          45

               6. _Corbulacea._          Two genera.
                    1. Corbula.            Species       10
                    2. Pandora.               „           4

               7. _Lithophaga._         Three genera.
                    1. Saxicava.           Species        9
                    2. Petricola.             „          13
                    3. Venerirupis.           „           8

               8. _Nymphacea._           Ten genera.
                    1. Sanguinolaria.      Species        9
                    2. Psammobia.             „          21
                    3. Psammotea.             „           7
                    4. Tellina.               „          68
                    5. Tellinides.            „           2
                    6. Corbis.                „           2
                    7. Lucina.                „          26
                    8. Donax.                 „          31
                    9. Capsa.                 „           3
                   10. Crassina.              „           1

               9. _Conchacea._          Seven genera.
                    1. Cyprina.            Species        2
                    2. Cytherea.              „          83
                    3. Venus.                 „         100
                    4. Veniricardia.          „           5
                    5. Cyclas.                „          15
                    6. Cyrena.                „          10
                    7. Galathea.              „           1

              10. _Cardiacea._          Five genera.
                    1. Cardium.            Species       57
                    2. Cardita.               „          23
                    3. Cypricardia.           „           5
                    4. Hiatelia.              „           2
                    5. Isocardia.             „           4

              11. _Arcacea._            Four genera.
                    1. Arca.               Species       41
                    2. Cucullæa.              „           1
                    3. Pectunculus.           „          22
                    4. Nucula.                „          45

              12. _Trigonacea._          Two genera.
                    1. Trigonia.           Species        1
                    2. Castalia.              „           1

              13. _Naiadea._            Four genera.
                    1. Unio.               Species      167
                    2. Hyria.                 „           2
                    3. Anodonta.              „          49
                    4. Iridina.               „           6

              14. _Chamacea._           Three genera.
                    1. Diceras.            Species        1
                    2. Chama.                 „          18
                    3. Etheria.               „           5

              15. _Tridacnea._           Two genera.
                    1. Tridacna.           Species        7
                    2. Hippopus.              „           1

              16. _Mytilacea._          Three genera.
                    1. Mytilus.            Species       42
                    2. Modiola.               „          32
                    3. Pinna.                 „          15

              17. _Mallacea._           Five genera.
                    1. Crenatula.          Species        7
                    2. Perna.                 „          10
                    3. Malleus.               „           6
                    4. Avicula.               „          19
                    5. Meleagrina.            „           2

              18. _Pectinea._           Seven genera.
                    1. Pedum.              Species        1
                    2. Lima.                  „           6
                    3. Pecten.                „          62
                    4. Plagiostoma.           „          10
                    5. Plicatula.             „           5
                    6. Spondylus.             „          21
                    7. Podopsis.              „           2

              19. _Ostracea._            Six genera.
                    1. Ostrea.             Species       49
                    2. Gryphea.               „           1
                    3. Vulsella.              „           6
                    4. Placuna.               „           3
                    5. Anomia.                „           9
                    6. Crania.                „           1

              20. _Brachiopoda._         Three gen.
                    1. Orbicula.           Species        1
                    2. Terebratula.           „          13
                    3. Lingula.               „           1


                               CLASS IV.

                               MOLLUSCA.

                         TWENTY-THREE FAMILIES.

               1. _Pteropoda._           Six genera.
                    1. Hyalea.             Species        2
                    2. Clio.                  „           2
                    3. Cleodora.              „           2
                    4. Limnacina.             „           1
                    5. Cymbulia.              „           1
                    6. Pneumodermon           „           1

               2. _Phyllidiacea._        Six genera.
                    1. Phyllidia.          Species        3
                    2. Chitonellus.           „           2
                    3. Chiton.                „          63
                    4. Patella.               „          49
                    5. Umbrella.              „           2
                    6. Pleurobranchus.        „           2

               3. _Calyptracea._         Seven gen.
                    1. Parmophorus.        Species        4
                    2. Emarginula.            „           5
                    3. Fissurella.            „          22
                    4. Pileopsis.             „           9
                    5. Calyptrea.             „           9
                    6. Crepidula.             „          13
                    7. Ancylus.               „           5

               4. _Bullacea._           Three genera.
                    1. Acera.              Species        1
                    2. Bullæa.                „           2
                    3. Bulla.                 „          19

               5. _Aplysiacea._          Two genera.
                    1. Dolabella.          Species        2
                    2. Aplysia.               „          37

               6. _Limacina._           Five genera.
                    1. Limax.              Species        5
                    2. Vitrina.               „           3
                    3. Testacella.            „           2
                    4. Parmacella.            „           2
                    5. Onchidium.             „           2

               7. _Colimacea._         Eleven genera.
                    1. Helix.              Species      203
                    2. Carocolla.             „          22
                    3. Achatina.              „          24
                    4. Anostoma.              „           3
                    5. Helicina.              „          19
                    6. Pupa.                  „          40
                    7. Clausilia.             „          15
                    8. Bulimus.               „          63
                    9. Succinea.              „           7
                   10. Auricula.              „          16
                   11. Cyclostoma.            „          38

               8. _Lymnacea._           Three genera.
                    1. Lymnea.             Species       33
                    2. Physa.                 „          10
                    3. Planorbis.             „          22

               9. _Melaniana._          Three genera.
                    1. Melania.            Species       54
                    2. Pirena.                „           6
                    3. Melanopsis.            „           3

              10. _Peristomiana._        Three gen.
                    1. Valvata.            Species        3
                    2. Paludina.              „          31
                    3. Ampularia.             „          13

              11. _Neritacea._          Four genera.
                    1. Neritina.           Species       27
                    2. Nerita.                „          20
                    3. Navicella.             „           4
                    4. Natica.                „          36

              12. _Ianthinea._           One genus.
                    1. Ianthina.           Species        3

              13. _Macrostomiana._        Four gen.
                    1. Sigaretus.          Species        6
                    2. Stomatella.            „           5
                    3. Stomatia.              „           2
                    4. Haliotis.              „          19

              14. _Plicacea._            Two genera.
                    1. Tornatella.         Species        6
                    2. Pyramidella.           „           6

              15. _Scalarina._          Three genera.
                    1. Scalaria.           Species       14
                    2. Vermetus.              „           2
                    3. Delphinula.            „           5

              16. _Turbinacea._          Eight gen.
                    1. Solarium.           Species        7
                    2. Trochus.               „          99
                    3. Monodonta.             „          34
                    4. Turbo.                 „          51
                    5. Planaxis.              „           4
                    6. Phasianella.           „          12
                    7. Turritella.            „          21
                    8. Rotella.               „           7

              17.  _Canalifera._         Eleven gen.
                    1. Cerithium.          Species       45
                    2. Pleurotoma.            „          29
                    3. Turbinella.            „          23
                    4. Cancellaria.           „          49
                    5. Fasciolaria.           „           8
                    6. Fusus.                 „          46
                    7. Pyrula.                „          29
                    8. Struthiolaria.      Species        2
                    9. Ranella.               „          15
                   10. Murex.                 „          73
                   11. Triton.                „          31

              18. _Alata._              Three genera.
                    1. Rostellaria.        Species        4
                    2. Pterecera.             „           7
                    3. Strombus.              „          32

              19. _Purpurifera._         Eleven gen.
                    1. Cassidaria.         Species        5
                    2. Cassis.                „          25
                    3. Ricinula.              „           9
                    4. Purpura.               „          62
                    5. Monoceros.             „           5
                    6. Concholepas.           „           1
                    7. Harpa.                 „           9
                    8. Dolium.                „           7
                    9. Buccinum.              „          66
                   10. Eburna.                „           5
                   11. Terebra.               „          24

              20. _Columellaria._       Five genera.
                    1. Columbella.         Species       20
                    2. Mitra.                 „          80
                    3. Voluta.                „          44
                    4. Marginellæ.            „          24
                    5. Volvaria.              „           7

              21. _Convoluta._           Six genera.
                    1. Cypræa.             Species      118
                    2. Ovula.                 „          12
                    3. Terebellum.            „           3
                    4. Ancillaria.            „           4
                    5. Oliva.                 „          63
                    6. Conus.                 „         181

              22. _Nautilacea._          Two genera.
                    1. Spirula.            Species        1
                    2. Nautilus.              „           2

              23. _Heteropoda._          Two genera.
                    1. Argonauta.          Species        3
                    2. Carinaria.             „           3

The American species are designated by a *.

[Illustration:

  _Pl. 1._

  _Parts of Shells_

  _P.S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 2._

  _Parts of Shells._

  _P.S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 3._

  _Parts of Shells._

  _P.S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 4._

  _Hinges of Shells._

  _P.S. Duval. Lith. Phil^a._
]

[Illustration:

  _Pl. 5._

  _1. Siliquaria, 2 Dentalium, 3 Pectinaria, 4 Sabellaria, 5 Terebella,
    6. Amphitrite, 7 Spirorbis, 8 Serpula, 9 Vermilia, 10 Galeolaria,
    11. Magilus, 12. Tubicinella, 13. Coronula, 14. Balanus, 15 Acasta,
    16 Creusia, 17 Pyrgoma, 18 Anatifera, 19 Pollicipes, 20 Cineras, 21.
    Otion, 22 Aspergillum._

  _P.S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 6._

  _1 Clavagella, 2 Fistulana, 3 Septaria, 4 Teredina, 5 Teredo, 6
    Pholas, 7 Gastrochæna, 8 Solen 9 Panopea, 10. Solecurtus, 11.
    Glycimeris 12 Mya, 13. Anatina, 14 Lutraria, 15 Mactra, 16.
    Crassatella, 17 Erycina, 18 Ungulina, 19 Solenimya, 20 Amphidesma,
    21 Corbula, 22 Pandora, 23 Saxicava._

  _P.S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 7._

  _1. Petricola 2 Venerirupis 3. Sanguinolaria, 4. Psammobia, 5.
    Psammotea, 6. Tellina, 7. Tellinides, 8. Corbis, 9. Lucina, 10.
    Donax, 11. Capsa, 12. Crassina, 13. Cyclas, 14. Cyrena, 15.
    Galathea, 16. Cyprina, 17. Cytherea, 18. Venus, 19. Venericardia,
    20. Cardium, 21. Cardita, 22. Cypricardia, 23. Hiatella._

  _P.S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 8._

  _1. Isocardia, 2. Cucullea, 3 Arca, 4. Pectuncules 5 Nucula, 6.
    Trigonia, 7 Castalia, 8. Unio, 9. Hyria, 10. Anodonta, 11. Iridina,
    12 Diceras, 13. Chama, 14. Etheria, 15 Tridacna, 16 Hippopus 17.
    Mytilus, 18. Modiola, 19 Pinna, 20. Crenatula, 21. Perna, 22.
    Malleus._

  _P. S. Duval. Lith. Phil^a._
]

[Illustration:

  _Pl. 9._

  _1. Avicula, 2 Meleagrina, 3 Pedum, 4 Lima, 5 Pecten, 6 Plagiostoma 7.
    Plicatula, 8 Spondylus, 9 Gryphea, 10 Ostrea, 11. Vulsella, 12
    Placuna, 13 Anomia, 14 Crania, 15 Orbicula, 16 Terebratula, 17
    Lingula, 18 Hyalea, 19 Cleodora, 20 Limacina, 21 Cymbulia, 22
    Chitonellus, 23 Chiton, 24 Patella, 25 Pleurobranchus, 26 Umbrella,
    27 Parmophorus, 28 Emurginula, 29 Fissurella._

  _P. S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 10._

  _1 Pileopsis, 2 Calyptera, 3 Crepidula, 4 Ancylus, 5 Bullæa, 6 Bulla,
    7 Aplysia, 8 Dolabella, 9 Parmacella, 10 Limax, 11 Testacella, 12
    Vitrina, 13 Helix, 14 Carocolla, 15 Anostoma, 16 Helicina, 17 Pupa,
    18 Clausilia, 19 Bulimus, 20 Achalina, 21 Succinea, 22 Auricula, 23
    Cyclostoma 24 Planorbis, 25 Physa, 26 Lymnea, 27 Melania, 28
    Melanospsis, 29 Pirena, 30 Valvata, 31 Paludina, 32 Ampularia, 33
    Neritina, 34 Navicella, 35 Nerita._

  _P. S. Duval, Lith. Phil^a._
]

[Illustration:

  _Pl. 11._

  _1 Natica, 2 Janthina, 3 Sigaretus, 4 Stomalella, 5 Stomatia, 6
    Haliotis, 7 Tornatella, 8 Pyramidella, 9 Vermetus, 10 Scalaria, 11
    Delphinula 12 Solarium, 13 Rotella, 14 Trochus, 15 Monodonata, 16
    Turbo, 17 Planaxis, 18 Phasianella, 19 Turritella, 20 Cerithium 21
    Pleurotoma, 22 Turbinella, 23 Cancillaria, 24 Fasciolaria, 25 Fusus,
    26 Pyrula, 27 Struthiolaria, 28 Ranella, 29 Murex, 30 Triton, 31
    Rostellaria._

  _P. S. Duval Lith. Phil^a._
]

[Illustration:

  _Pl. 12._

  _1 Pteroceras, 2 Strombas, 3 Cassidaria, 4 Cassis, 5 Ricinula, 6
    Purpura, 7. Monoceros, 8 Concholepas, 9 Harpa 10 Dolium, 11 Buccinum
    12 Eburna, 13 Terebra, 14 Columbella, 15 Mitra, 16 Voluta 17
    Marginella 18 Volvaria, 19 Ovula, 20 Cyprea, 21 Terebellum, 22
    Ancillaria, 23 Olivia, 24 Conus, 25 Spirula, 26 Nautilus 27
    Argonauta, 28 Carinaria._

  _P. S. Duval, Lith. Phil^a._
]




                              CONCHOLOGY.




                                CLASS I.
                               ANNULATA.


Animal soft, elongated, vermiform, naked or inhabiting a tube, which it
never entirely quits; the body furnished either with segments or
transverse wrinkles; often without a head, eyes or antennæ; without
articulated feet, but most of them having in their place bristly,
retractile knobs, disposed in lateral rows: mouth subterminal, either
simple, orbicular, with lips, or in the form of a proboscis; often with
jaws, a knotted longitudinal medulla, and nerves for sensation and
motion; the blood red, circulating by means of arteries and veins:
respiration by external or internal branchiæ, which are sometimes
imperceptible. _Four Families._


                               FAMILY I.

                         DORSALIA. Two Genera.


                         1. Genus _Arenicola_.

_Animal._ The gills, or respiratory organs dorsal, or disposed
lengthways on the body.

_Shell._ Supposed to be tubular. One species.

Arenicola piscatorium.


                     2. Genus _Siliquaria_. Pl. V.

_Animal._ See Arenicola.

Shell very thin, conical, tubular, involuted in a spiral manner, loosely
and irregularly; aperture circular, sharp edges, interrupted in the
middle by a notch, extending like a slit through the greater portion of
its length, and stopping abruptly at some distance from the summit.
Inhabits the Indian seas. Eight species.

 Siliquaria anguina.
 S. muricata.
 S. lævigata.
 S. lactæa.
 S. rugosa.
 S. terebella.
 S. lima.
 S. spinosa.


                               FAMILY II.

                         MALDANIA. Two Genera.


                          1. Genus _Clymene_.

_Animal._ Respiratory organs not determined, supposed to be at the
posterior part of the body.

_Shell._ Tube thin and slender, open at both ends, encrusted externally
with sand and fragments of shells. One species.

Clymene amphistoma.


                      2. Genus _Dentalium_. Pl. V.

_Animal._ Body elongated, conical, sub-vermiform, enveloped in a fistula
mantle as far as the anterior third, and ending in a bourrelet pierced
in its middle by an orifice with fringed edges; foot altogether
anterior, proboscidiform, terminated by a conical appendage, contained
in a kind of cup with festooned edges; head distinct, oval, with a
terminal mouth in the middle of a digitated lip; a pair of lateral jaws,
formed each of two little oval shells garnished with points.

_Shell._ Tubular, regular, symmetrical, slightly curved longitudinally,
tapering gradually to the rear, and opening in a round orifice at each
end. Inhabits the British seas. Twenty-one species.

 Dentalium elephantinum.
 D. aprinum.
 D. sulcatum.
 D. fasciatum.
 D. pseudo-antalis.
 D. radicula.
 D. antalis.
 D. arictinum.
 D. octogonum.
 D. deforme.
 D. novemcostatum.
 D. sexangulaire.
 D. striatum.
 D. dentalis.
 D. corneum.
 D. nigrum.
 D. politum.
 D. eburneum.
 D. clava.
 D. fissura.
 D. coarctatum.


                              FAMILY III.

                       AMPHITRITÆA. Four Genera.


                     1. Genus _Pectinaria_. Pl. V.

_Animal._ Respiratory organs in general known, and disposed at or near
the anterior part of the body; not separated or covered by an operculum.

_Shell._ A membranous papyraceous tube in the form of a reversed cone;
unfixed; exterior covered with sandy adhesions. Two species.

 Pectinaria capensis.

 P. belgica.*


                     2. Genus _Sabellaria_. Pl. V.

_Animal._ But slightly differing from the Pectinaria.

_Shell._ Tubes numerous, united in a common mass, composed of
agglutinated particles of marine substances, cellular at the base;
orifice expanded. Found in the Indian Ocean. Two species.

 Sabellaria alveolata.
 S. crassissima.


                      3. Genus _Terebella_. Pl. V.

_Animal._ Body tubicular, elongated, cylindrically depressed, attenuated
posteriorly; a row of nodulous and setiferous papillæ on each side;
numerous filiform, twisted tentacula surrounding the mouth.

_Shell._ An elongated cylindrical and membranous tube with lash-like
appendages at the end; covered with adhesions of sand and shells.
Inhabits the coast of New Holland. Four species.

 Terebella conchilega.
 T. ventricosa.
 T. cristata.
 T. vermicuta.


                     4. Genus _Amphitrite_. Pl. V.

_Animal._ Body tubicular, elongated, cylindrical, attenuated behind with
many annulated segments.

_Shell._ An elongated cylindrical tube growing thinner towards the base,
of a tough membranous texture, and generally without adhesions.
Mediterranean sea. Seven species.

 Amphitrite ventilabra.
 A. penicilla.
 A. magnifica.
 A. vesiculosa.
 A. volutacornis.
 A. infundibula.
 A. minima.


                               FAMILY IV.

                        SERPULACEA. Five Genera.


                      1. Genus _Spirorbis_. Pl. V.

_Animal._ Gills or respiratory organs separated or covered by an
operculum.

_Shell._ A testaceous tube turned spirally on a horizontal plane, the
lower portion of which is attached to marine substances, generally fuci:
opening of the tube terminal, rounded or angular. Found on Algæ on the
British coast. Six species.

 Spirorbis nautiloidis.
 S. spirilla.
 S. tricostalis.
 S. bicarinata.
 S. carinata.
 S. lamellosa.


                       2. Genus _Serpula_. Pl. V.

_Animal._ Body tubular, elongated, depressed, and attenuated behind;
segments numerous and narrow; small bundles of awl-shaped bristles in a
single row on each side.

_Shell._ A solid calcareous tube, brown, purple, yellow, tawny, pink,
white, or tinged with green. The shells are irregularly twisted, in
clusters, and affixed to other substances. Inhabits the coast of
Britain. Twenty-six species.

 Serpula vermicularis.
 S. fascicularis.
 S. intestina.
 S. contortuplicata.
 S. plicaria.
 S. glomerata.
 S. decussata.
 S. protensa.
 S. infundibula.
 S. annulata.
 S. cereola.
 S. filograna.
 S. vermicella.
 S. filaria.
 S. pellucida.
 S. intorta.
 S. cristata.
 S. spirulæa.
 S. quadrangularis.
 S. minima.
 S. echinata.
 S. sulcata.
 S. costalis.
 S. dentifera.
 S. sipho.
 S. arenaria.


                      3. Genus _Vermilia_. Pl. V.

_Animal._ Body tubicular, elongated and attenuated towards the posterior
part, and provided superiorly with a simple testaceous orbicular
operculum.

_Shell._ A testaceous cylindrical tube, narrowed in the rear, twisted,
and adhering by the side to marine substances, aperture round, the
margin armed with from one to three teeth. Inhabits the British coast.
Nine species.

 Vermilia rostrata.
 V. triquetra.
 V. bicarinata.
 V. eruca.
 V. subcrenata.
 V. plicifera.
 V. scabra.
 V. tæniata.
 V. plicata.


                     4. Genus _Galeolaria_. Pl. V.

_Animal._ Distinguished from the vermilia by a very peculiar operculum.

_Shell._ In groups, testaceous, cylindrical, subangular, wavy, adhering
by the base, and open at the summit; aperture orbicular, terminated on
the side by a spatular tongue; operculum orbicular, squamose, and
consisting of from five to nine testaceous parts or valves. Inhabits the
Indian seas. Two species.

 Galeolaria cæspitosa.
 G. elongata.


                       5. Genus _Magilus_. Pl. V.

_Animal._ Unknown.

_Shell._ Usually found imbedded in a species of Madrepore. Base bent
into a spiral form, oval, with four contiguous, convex volutions (the
last of which is the largest), and prolonged into a straight waved tube,
convex above, carinated beneath. Inhabits the sea at the Isle of France.
Two species.

 Magilus antiquus.
 M. muricatus.




                               CLASS II.
                              CIRRHIPEDA.


_Animal._ Soft, without head or eyes, testaceous, body fixed as if
reversed, inarticulated, furnished with a mantle, having above
tentacular arms, with curled tufts multiarticulated, mouth beneath, not
projecting, dentated transverse jaws disposed in pairs. Number of arms,
unequal and varying, disposed in rows, each composed of two rows of
curled tufts of bristles; fringed; a corneous skin supported by a
pedicle. Medulla longitudinal and knotted; gills external, sometimes
concealed; circulation by heart and vessels. One Family.


                                FAMILY.

                        CIRRHIPEDA. Ten Genera.


                        1. Genus _Tubicinella_.

_Animal._ Body inclosed in a shell, with small setaceous and unequal
cirri.

_Shell._ Univalve, operculated, tubular, erect, a little attenuated
towards the base, bound with annular transverse ribs, truncated at both
ends, open at the summit, and closed at the base with a membrane.
Operculum with four obtuse valves. South American seas. One species.

 Tubicinella balænarum.


                      2. Genus _Coronula_. Pl. V.

_Animal._ Body seated, enveloped in a shell with small setaceous and
cirrous arms.

_Shell._ Sessile, apparently indivisible, suborbicular, conoidal or
blunt, conical, the extremities truncated, the sides very thick, the
inside hollowed into radiating cells. Operculum composed of four obtuse
valves. Inhabits the North seas. Five species.

 Coronula diadema.
 C. testudinaria.
 C. balænaris.
 C. pulchra.

 C. denticulata.*


                       3. Genus _Balanus_. Pl. V.

_Animal._ Body sessile, inclosed in an operculated shell; branchiæ
numerous, placed in two rows, unequal, articulated, ciliated; each
composed of two cirri, supported by a peduncle, and exsertile; mouth
with four transverse dentated jaws, with four hairy palpi-like
appendages.

_Shell._ Formed of six distinct coronary valves, one dorsal, one
ventral, and two pairs of laterals, with a calcareous support; operculum
forming a sort of pyramid, by four articulated pieces in the aperture of
the shell. Is found in almost all seas. Thirty species.

 Balanus angulosus.
 B. nigrescens.
 B. roseus.
 B. amphimorphus.
 B. crispatus.
 B. stalaciferus.
 B. patellaris.
 B. calycularis.
 B. subimbricatus.
 B. palmatus.
 B. dupluconus.
 B. semiplicatus.
 B. lævis.
 B. punctatus.
 B. perforatus.
 B. rugosus.
 B. latus.
 B. plicatus.
 B. galeatus.
 B. spinosus.
 B. placianus.
 B. sulcatus.
 B. cylindraceus.
 B. ovularis.
 B. radiatus.
 B. fistulosus.
 B. Lyonsii.

        ·       ·       ·       ·       ·

 B. tintinabulus.*
 B. miser.*
 B. geniculatus.*


                       4. Genus _Acasta_. Pl. V.

_Animal._ Body without a peduncle, and inclosed in a multivalve shell,
found in sponge or marine bodies, mouth and tentacula placed in the
apex, or upper part of the body.

_Shell._ Patella-shaped, sub-conically oval, formed of six lateral
unequal valves forming the base, which being convex prevents the shell
from standing by itself in an erect position, when detached from the
substance which envelopes it. Inhabits the British seas. Four species.

 Acasta Montaguii.
 A. sulcata.
 A. glans.
 A. tubulosa.


                       5. Genus _Creusia_. Pl. V.

_Animal._ Body, subglobular, inclosed in an operculated shell; having
three or four pairs of tentacular arms: mouth at the anterior part of
the body.

_Shell._ Sessile, fixed, orbicular, conical, consisting of four united
unequal valves; attached to madrepore and other marine substances, they
are almost microscopic, and found only in the seas of hot countries.
Inhabits the China seas. Three species.

 Creusia stromia.
 C. spinulosa.
 C. verruca.


                       6. Genus _Pyrgoma_. Pl. V.

_Animal._ As above.

_Shell._ Sessile, univalve, rather globular, ventricose, convex above;
apex perforated; aperture small, elliptical, operculum quadrivalve.
Inhabits the Indian seas. One species.

 Pyrgoma cancellata.


                      7. Genus _Anatifera_. Pl. V.

_Animal._ Body covered with a shell, supported by a long tubular
tendinous peduncle; with long, numerous, and unequal tentacular arms,
which are articulated and ciliated, and emanating from the summit on one
side.

_Shell._ Compressed on the sides, with five flat valves, the valves
contiguous and unequal; the lower lateral ones the largest: the whole of
them united and kept together by means of their membranes. Inhabits the
British seas. Six species.

 Anatifera lævis.
 A. villosa.
 A. vitrea.
 A. dentata.
 A. striata.
 A. aculeata.


                     8. Genus _Pollicipes_. Pl. V.

_Animal._ Body covered by a shell, and supported on a tabular,
tendinous, scaly peduncle; with many tentacular arms.

_Shell._ Consisting of thirteen or more valves, the smallest at the
sides, which are very flat and compressed, the peduncle short, wrinkled,
rigid, and often covered with scales like shagreen. Inhabits the
European and American seas. Six species.

 Pollicipes cornucopia.
 P. scalpellum.
 P. homii.
 P. mitella.
 P. peronii.

        ·       ·       ·       ·       ·

 P. Mortoni.*


                       9. Genus _Cineras_. Pl. V.

_Animal._ Body pedunculated, and encased in a membranous tunic, which is
swollen above, with an opening below the summit, from which protrude
many ciliated articulated arms.

_Shell._ Composed of five testaceous oblong valves, two at the sides of
the aperture and three on the back, not covering the whole of the body;
supported by a peduncle of a greenish colour with several longitudinal
stripes. Inhabits the British coast. One species.

 Cineras vittata.


                       10. Genus _Otion_. Pl. V.

_Animal._ Body pedunculated, enveloped in a membranous tunic, which is
ventricose above; two horn-like tubes, directed backwards, truncated,
and open at their points, and situated in the apex of the tunic; having
a lateral opening, with many articulated and ciliated arms.

_Shell._ Composed of two testaceous valves, attached near the lateral
opening, the centre aperture admitting the animal’s tentaculæ, the
singular form of which prevents its being blended with the genus cineras
without a further examination of its structure. Inhabits the North seas.
Two species.

 Otion Cuvieri.
 O. Blainvillii.




                               CLASS III.
                              CONCHIFERA.


_Animal._ Soft, inarticulated, always fixed in a bivalve shell, without
head or eyes, having the mouth naked, concealed, and without any hard
parts; a large mantle enveloping the whole of the body, forming two
laminiform lobes; the edges detached or sometimes united in front. Gills
or respiratory organs external, situated on each side between the body
and the mantle; circulation simple, the heart with one ventricle; some
few ganglions of the different nerves, but no knotted medullary cord.

_Shell._ Always bivalve, enveloping the animal entirely or partially,
sometimes free, sometimes affixed; the valves most frequently united on
one side by a hinge or ligament. Sometimes attached to the shell are
testaceous accessory pieces. Twenty families.


                               FAMILY I.

                         TUBICOLA. Six Genera.


                     1. Genus _Aspergillum_. Pl. V.

_Animal._ Entirely unknown.

_Shell._ Oval, somewhat elongated, striated longitudinally, conic,
club-shaped, having two valves incrusted on one side of the club, open
at its attenuated extremity, and terminated at the other by a convex
disk, pierced by a number of small perforations, and encircled by a
dilated margin of papyraceous tubes, resembling a plaited ruff—smaller
extremity always open. This is a well known, but rare shell, found in
sandy places in low water in the Indian ocean. Four species.

 Aspergillum Javanum.
 A. vaginiferum.
 A. Novæ Zælandiæ.
 A. agglutinans.


                     2. Genus _Clavagella_. Pl. VI.

_Animal._ Unknown.

_Shell._ A tubular sheath, testaceous, attenuated, and open before;
terminating posteriorly in an oval, sub-compressed club, roughened by
spiniform tubes—one valve fixed in the side of the club, the other free
in the tube. Inhabits the Indian seas. Four species.

 Clavagella aperta.
 C. cristata.
 C. tibialis.
 C. Brocchii.


                     3. Genus _Fistulana_. Pl. VI.

_Animal._ Provided with two protuberant calcareous tubes, covering parts
of its body at the open end of the tube, each of which is terminated
with from five to eight cup-shaped calcareous or corneous appendages. It
inhabits the sand, and perforates wood, stones, and sometimes shells.

_Shell._ Lamarck asserts that the tube and shell of this genus are quite
distinct. They have the shell free and detached within the sheath, and
neither of the valves fixed into the partition of the tube, which is
most generally testaceous, closed, and retort-shaped at the posterior
extremity. Inhabits the Indian seas. Four species.

 Fistulana clava.
 F. corniformis.
 F. gregata.
 F. lagenula.


                      4. Genus _Septaria_. Pl. VI.

_Animal._ Unknown.

_Shell._ A very long testaceous tube, gradually attenuated to its upper
end, and divided internally by vaulted divisions seldom complete, the
extremity of which is terminated by two slender tubes without interior
partitions. Specimens of this genus have been found five feet long.
Found in sand on the shores of the Indian seas. Two species.

 Septaria arenaria.
 S. maculata.


                      5. Genus _Teredina_. Pl. VI.

A fossil genus; consisting of a testaceous cylindrical sheath, the
posterior extremity closed, and exhibiting the two valves of the shell
it encloses; the anterior end open. Two fossil species.


                       6. Genus _Teredo_. Pl. VI.

_Animal._ Body very much elongated, vermiform: mantle very fine,
tubular, opening only at front and below for the issue of a teat-shaped
foot; mouth small; very short, distinct tubes; the inferior or
respiratory one somewhat larger than the superior; labial appendages
short and striated; branchiæ very long, narrow, united, and prolonged
throughout the extent of the tubular cavity of the mantle; only one
large contractile muscle between the valves; at the point of junction of
the mantle and tubes is a muscular ring, in which is implanted a pair of
corneo-calcareous appendages.

_Shell._ Thick, solid, very short or annular, open before and behind;
valves equal, equilateral, angular and trenchant before, only touching
each other by the opposite edges; no hinge; a considerable spoon-like
cavity; only one feeble muscular impression. Tube more or less distinct
from the substance in which the animal lives, cylindrical, straight or
winding, and closing with age at the buccal extremity so as to envelope
the animal and its shell; at the other end it is always open, and
divided internally into two syphons by a partition in the middle.
Inhabits the European seas in timber. Three species.

 Teredo navalis.
 T. palmulata.
 T. gigantea.


                               FAMILY II.

                        PHOLADARIA. Two Genera.


                       1. Genus _Pholas_. Pl. VI.

_Animal._ Without a tubular sheath, projecting anteriorly into two
united tubes, frequently surrounded by a common skin, and the posterior
extremity provided with a short muscular foot, flattened at its
extremity.

_Shell._ Multivalve, equivalve, transverse, gaping at both ends, with
various accessory pieces either on the hinge or below it. Inhabits the
Indian seas and American shores. Eighteen species.

 Pholas dactyla.
 P. orientalis.
 P. candida.
 P. dactiloides.
 P. papyracea.
 P. tuberculata.
 P. silicula.
 P. callosa.

        ·       ·       ·       ·       ·

 P. costata.*
 P. clavata.*
 P. ovum.*
 P. lancellata.*
 P. crispata.*
 P. truncata.*
 P. californica.*
 P. penita.*
 P. oblongata.*
 P. cuneiformis.*


                    2. Genus _Gastrochæna_. Pl. VI.

_Animal._ Unknown.

Always without accessory pieces, therefore easily distinguished from the
Pholas.

_Shell._ Equivalve, somewhat cuneiform with a very large oval and
oblique aperture anteriorly; posterior extremity nearly closed; hinge
linear; marginal and without teeth. Three species.

 Gastrochæna cuneiformis.
 G. mytiloides.
 G. modiolina.


                              FAMILY III.

                         SOLENEA. Four genera.


                       1. Genus _Solen_. Pl. VI.

_Animal._ Body cylindroid, much elongated; the mantle in form of a canal
open at both ends, closed in the rest of its extent by a thick epidermis
which surrounds it; a cylindroid anterior foot.

_Shell._ Equivalve, extremely inequilateral, the summits very small, and
entirely at the commencement of the dorsal line; one or two teeth in the
hinge. Inhabits the seas of America and Europe. Twenty-one species.

 Solen vaginus.
 S. corneus.
 S. pygmæus.
 S. ambiguus.
 S. Dombeii.
 S. Javanicus.
 S. Caribæus.
 S. violaceus.
 S. antiquatus.
 S. vaginoides.
 S. siliqua.
 S. cultellus.
 S. planus.
 S. constrictus.
 S. coarctatus.

        ·       ·       ·       ·       ·

 S. ensis.*
 S. minutus.*
 S. viridis.*
 S. centralis.*
 S. rostratus.*
 S. giganteus.*


                      2. Genus _Panopæa_. Pl. VI.

_Animal._ Unknown.

The situation of the ligament, and the prominency of the apex, are the
characters which distinguish it from the Mya.

_Shell._ Regular oval, elongated, gaping at both ends, equivalve,
inequilateral; summit little marked and anterodorsal; hinge complete;
similen formed by a conical primary tooth, before a short, compressed,
ascending callosity, ligament exterior, attached to the callosity; two
muscular impressions. Inhabits the Mediterranean Sea. One species.

 Panopæa Aldrovandi.


                     3. Genus _Solecurtus_. Pl. VI.

_Animal._ Unknown.

_Shell._ Oval, elongated, equivalve, subequilateral, with edges nearly
straight and parallel, the extremities equally rounded, and, as it
were, truncated; summits but little marked; hinge without teeth, or
formed by some rudimentary primary teeth, ligament projecting, affixed
to thickened callosities; two distinct rounded muscular
impressions.—Mediterranean Sea and coasts of America. Ten species.

 Solecurtus radiatus.
 S. strigilatus.
 S. legumen.

        ·       ·       ·       ·       ·

 S. fragilis.*
 S. costatus.*
 S. Caribæus.*
 S. lucidus.*
 S. Nuttallii.*
 S. subteres.*
 S. Californianus.*


                     4. Genus _Glycimeris_. Pl. VI.

_Animal._ Unknown.

The few species of this genus yet known have been blended, by previous
authors, either with the Mya or Solen, but from either they are easily
distinguished.

_Shell._ Covered with epidermis, slightly irregular, elongated, gaping
at both ends, equivalve, exceedingly inequilateral; summits little
marked; hinge toothless; a longitudinal callosity. Ligament exterior,
affixed to very projecting callosities on the shortest side of the
shell; two distinct muscular impressions. Inhabits the North seas. Two
species.

 Glycimeris margaritacea.
 G. siliqua.


                               FAMILY IV.

                          MYARIA. Two genera.


                        1. Genus _Mya_. Pl. VI.

_Animal._ Subcylindrical, enveloped in a mantle pierced only with one
interior and inferior hole for the passage of a very small and conical
foot; the tubes very considerable, and completely united; a tolerably
large mouth, oval, and with simple lips; very small labial appendages:
branchial laminæ inconsiderable; the external very short, the internal
united with that of the opposite side.

_Shell._ Surrounded with a thick epidermis, which is prolonged upon the
tubes and the edges of the mantle of the animal; tolerably solid, with
fine trenchant edges; the summits very little marked; hinge dissimilar;
one or two oblique cardinal folds, divergent, behind a horizontal
spoon-shaped hollow upon the left valve, corresponding with a hollow;
horizontal and cardinal in the right valve; two distinct muscular
impressions. Inhabits the British and American coasts. Eight species.

 Mya truncata.
 M. arenaria.
 M. erodona.
 M. solenimyalis.

        ·       ·       ·       ·       ·

 M. hyalina.*
 M. cancellata.*
 M. acuta.*
 M. mercenaria.*


                      2. Genus _Anatina_. Pl. VI.

_Animal._ Unknown.

_Shell._ Transverse, subequivalve, gaping at both valves, or in one
only; no cardinal teeth; one broad primary tooth in both valves,
projecting interiorly; a lateral plate running obliquely under the
primary teeth. Sometimes there is a fissure extending from the apex,
giving the appearance of a second plate or rib. Inhabits the British and
American seas. Twelve species.

 Anatina laterna.
 A. truncata.
 A. subrostrata.
 A. trapezoides.
 A. rugosa.
 A. imperfecta.
 A. longirostris.
 A. globulosa.
 A. myalis.
 A. rupicola.

        ·       ·       ·       ·       ·

 A. Leana.*
 A. papyracea.*


                               FAMILY V.

                        MACTRACEA. Seven genera.


                      1. Genus _Lutraria_. Pl. VI.

_Animal._ Body oval, much compressed, or subcylindrical; the mantle
enclosed only in the half of its inferior side: foot small and
projecting but little beyond the abdominal mass, tubes long, distinct or
united. This genus is perfectly distinct from the Mactra, to which it
formerly belonged, on account of its having no lateral teeth. It is
called by De Blainville, Lutricola, from its being found very deep in
mud or sand at the mouth of rivers.

_Shell._ Oval or elongated, regular, equivalve, more or less
inequilateral, sometimes but slightly gaping: edges always simple and
trenchant; summits feebly marked; hinge subsimilar, formed by two very
small divergent cardinal teeth; two very distinct muscular impressions
united by a palleal impression profoundly sineous to the rear. Inhabits
the seas of Europe and America. Fourteen species.

 Lutraria solenoides.
 L. rugosa.
 L. compressa.
 L. piperata.
 L. tellinoides.
 L. candida.
 L. elliptica.
 L. papyracea.
 L. plicatella.
 L. crassiplica.
 L. complanata.

        ·       ·       ·       ·       ·

 L. lineata.*
 L. Nuttallii.*
 L. caniculata.*


                       2. Genus _Mactra_. Pl. VI.

_Animal._ Body oval and pretty thick; edges of the mantle thick, smooth,
or without tentacular papillæ, augmented behind by two indistinct tubes;
mouth small and oval; labial appendages narrow; branchial laminæ very
small, and united in their length among themselves and with those of the
opposite side; foot oval, trenchant, very long.

_Shell._ The Mactra has a peculiar hinge distinguishing it from all
other genera. It is triangular, with a curved or angular compressed
tooth on each valve, with a small oblique cavity on each side, to which
is attached the ligament. Two lateral teeth, one near the primary tooth
and one near the ligament. The shape of the shell is subtriangular or
oblong; exterior smooth, striated, or ribbed transversely; two muscular
impressions united by a narrow marginal tongue. Inhabits the British and
American coasts. Forty-four species.

 Mactra spengleri.
 M. striatella.
 M. carinata.
 M. straminea.
 M. Australis.
 M. violacea.
 M. fasciata.
 M. turgida.
 M. plicataria
 M. rufescens.
 M. maculata.
 M. subplicata.
 M. triangularis.
 M. lactea.
 M. abbreviata.
 M. crassatella.
 M. helvacea.
 M. grandis.
 M. stultorum.
 M. maculosa.
 M. ovalina.
 M. castanea.
 M. rufa.
 M. squalida.
 M. brasiliana.
 M. donacina.
 M. depressa.
 M. lilacea.
 M. trigonella.
 M. deltoides.
 M. alata.

        ·       ·       ·       ·       ·

 M. gigantea.*
 M. solida.*
 M. oblonga.*
 M. californica.*
 M. arctata.*
 M. nucleus.*
 M. alba.*
 M. similis.*
 M. fragilis.*
 M. lateralis.*
 M. deaurata.*
 M. planulata.*
 M. tellinoides.*


                    3. Genus _Crassatella_. Pl. VI.

_Animal._ Unknown.

_Shell._ Close, suborbicular or transverse, striated longitudinally,
denticulated, regular, equivalve, inequilateral, summits well marked,
and turned to the front: primary teeth somewhat divergent with a hollow
at the side; no lateral teeth nor obsolete ones; ligament internal and
inserted into a pit in the hinge. It is easily known from the Mactra and
Lutraria by the valves fitting exactly. The living species of this genus
only exist in the seas of Australasia, while in a fossil state we find
at least seven species in France. Eleven species.

 Crassatella kingicola.
 C. donacina.
 C. sulcata.
 C. rostrata.
 C. glabrata.
 C. subradiata.
 C. contraria.
 C. cuneata.
 C. Erycinæa.
 C. cycladea.
 C. striata.


                      4. Genus _Erycina_. Pl. VI.

_Animal._ Unknown.

_Shell._ Somewhat longer than high, subtrigonal, regular equivalved,
inequilateral, gaping but little or not at all; summits well marked and
a little inclined to the front; hinge subsimilar; two unequal cardinal
teeth converging to the summit; two oblong, compressed, short, and
inserted lateral teeth; ligament internal and situated in a pit. Owing
to the equivocal character of this genus it is somewhat difficult to
judge of the hinge. Inhabits the Indian and American seas. Two species.

 Erycina cardioides.
 E. striata.


                      5. Genus _Ungulina_. Pl. VI.

_Animal._ Unknown.

_Shell._ Vertical or sublongitudinal, a little irregular, not gaping,
equivalve, subequilateral, with summits a little marked; hinge dorsal,
formed by a cardinal tooth; two long muscular impressions, one short
primary cleft tooth in each valve, with an oblong groove divided in the
middle of the margin, ligament internal inserted in a pit. Two species.

 Ungulina oblonga.
 U. transversa.


                      6. Genus _Solemya_. Pl. VI.

_Animal._ Unknown.

_Shell._ Covered with a thick epidermis, enclosing it entirely except at
the extremities, regular, somewhat thick, oval, elongated, straight and
parallel edges, also rounded at its two extremities, valves equal, very
inequilateral; the anterior side much longer than the posterior; summits
feebly marked; hinge subsimilar, formed by a cardinal tooth, dilated,
compressed, and a little reflexed above; subexterior ligament inserted
upon the tooth, and nearly at the posterior extremity of the shell; two
small, rounded, widely separated muscular impressions, without any
visible abdominal impression. Four species.

 Solemya Australis.
 S. Mediterranea.

        ·       ·       ·       ·       ·

 S. velum.*
 S. borealis.*


                     7. Genus _Amphidesma_. Pl. VI.

_Animal._ Very imperfectly known.

_Shell._ Transverse, inequilateral, somewhat rounded or suboval; sides
slightly gaping; hinge with one or two cardinal teeth, and a narrow
groove for the internal ligament; ligament double, the external one
short, the internal one fixed in the internal grooves. The two ligaments
distinguish this genus from all other bivalves. Inhabits the West Indian
and American seas. Forty-five species.

 Amphidesma variegatum.
 A. donacillum.
 A. lacteum.
 A. corneum.
 A. albellum.
 A. flexuosum.
 A. prismaticum.
 A. phaseolinum.
 A. Tenuii.
 A. purpurescens.
 A. nucleolum.
 A. physioides.
 A. pulchrum.
 A. pallidum.
 A. formosum.
 A. roseum.
 A. corbuloides.
 A. glabrellum.
 A. lucinale.
 A. Boysii.
 A. lenticulare.
 A. cancellatum.
 A. reticulatum.
 A. duplicatum.
 A. læve.
 A. prismaticum.
 A. ellipticum.
 A. subtruncatum.
 A. solidum.
 A. cordiforme.
 A. rupium.
 A. lamellosum.
 A. crenulatum.
 A. punctatum.
 A. multicostatum.
 A. siculum.

        ·       ·       ·       ·       ·

 A. transversum.*
 A. rubro-lineata.*
 A. decisa.*
 A. bellastriata.*
 A. orbiculata.*
 A. equalis.*
 A. punctata.*
 A. radiata.*
 A. lepida.*


                               FAMILY VI.

                        CORBULACEA. Two genera.


                      1. Genus _Corbula_. Pl. VI.

_Animal._ Unknown.

_Shell._ Tolerably solid, regular, inequivalve, inequilateral with a
conical, flexed, ascending, primary tooth in each valve; a cavity at the
side; no lateral teeth; ligament interior, placed in the cavities; two
neighbouring muscular impressions. Inhabits the British and American
seas. Ten species. Four fossil.

 Corbula Australis.
 C. sulcata.
 C. erythrodon.
 C. ovalina.
 C. semen.
 C. Taitensis.
 C. nucleus.
 C. impressa.
 C. porcina.

        ·       ·       ·       ·       ·

 C. contracta.*


                      2. Genus _Pandora_. Pl. VI.

_Animal._ Body much compressed, somewhat elongated, in form of a furrow,
in consequence of the union of the edges of the mantle, and its
continuation with the tubes, which are united and short; foot small,
thickest in front, and issuing through a tolerably large cleft in the
mantle.

_Shell._ Regular, white, elongated, much compressed, inequivalved,
inequilateral; right or upper valve quite flat, with a fold; summits
feebly marked; hinge anomalous, formed by a transverse cardinal tooth on
the right; valve entering a corresponding cavity in the left; ligament
internal, oblique, triangular, inserted in a somewhat deep pit, with
edges a little projecting on each valve; two round muscular impressions.
Inhabits the Mediterranean, British, and American seas. Four living
species, and two fossils, according to Defrance.

 Pandora rostrata.
 P. obtusa.

        ·       ·       ·       ·       ·

 P. trilineata.*
 P. punctata.*


                              FAMILY VII.

                       LITHOPHAGA. Three genera.


                      1. Genus _Saxicava_. Pl. VI.

_Animal._ Long, subcylindrical, the mantle closed in all parts,
prolonged behind by two long tubes, thick and close together externally,
pierced interiorly and in front with a round orifice, for the passage of
a very small foot; mouth very large; labial appendages small; branchial
laminæ free, the external pair much shorter than the internal.

Lamarck has thought proper to remove this genus from the Mytilus; it
possesses the faculty, like the Pholas, of penetrating rocks and
substances, and cannot be extracted but by breaking the substance in
which it is imbedded.

_Shell._ Thick, with an epidermis, a little irregular, elongated,
subcylindrical, obtuse at both ends; summits feebly marked; hinge
toothless, or with a very small rudimentary tooth; ligament external,
somewhat inflated; two round muscular impressions distinct, and several
others irregular. Inhabits the British and American seas, in cavities,
which they bore in rocks or wood. Nine species.

 Saxicava rugosa.
 S. gallicana.
 S. veneriformis.
 S. pholadis.
 S. Australis.

        ·       ·       ·       ·       ·

 S. distorta.*
 S. rhomboides.*
 S. carditoides.*
 S. californica.*


                     2. Genus _Petricola_. Pl. VII.

_Animal._ Unknown.

_Shell._ Subtrigonal, more or less irregular, transverse, inequilateral;
upper side narrowed and a little gaping; lower side rounded; hinge with
two teeth in each valve, or in one valve only. Inhabits the Australian
seas, boring into wood and rocks. Thirteen species.

 Petricola lamellosa.
 P. Ochrolenca.
 P. Semilamellata.
 P. lucinalis.
 P. striata.
 P. costellata.
 P. recellaria.
 P. exilis.
 P. ruperella.
 P. chamoides.
 P. pholadiformis.
 P. labagella.
 P. linguatula.


                    3. Genus _Venerirupis_. Pl. VII.

_Animal._ Unknown, but probably resembling the Venus.

Another lithophagous shell, taken from the genus Venus, and
distinguished from it by the different disposition of the teeth.

_Shell._ Transverse, inequilateral, posterior side short, the anterior
gaping slightly. Hinge with two teeth on the right valve, three on the
left, and sometimes three on both—these are small, near together, and
parallel. Ligament exterior. Inhabits the British seas, boring into
rocks and clay. Eight species.

 Venerirupis perforans.
 V. nuclea.
 V. Ira.
 V. corditoides.
 V. exotica.
 V. distans.
 V. crenata.
 V. alata.


                              FAMILY VIII.

                         NYMPHACEA. Ten Genera.

This family is divided into N. Solenaria and N. Tellinaria, from their
resemblance to the Solen and Tellina.

N. SOLENARIA. Three genera.


                   1. Genus _Sanguinolaria_. Pl. VII.

_Animal._ Unknown.

_Shell._ Oval, compressed, a little elongated, gaping but little,
equivalve, subequilateral, rounded at both extremities; no mark of
posterior keel; summits feebly marked; hinge formed by one or two
contiguous cardinal teeth upon each valve; ligament projecting, two
round muscular impressions, distant and joined by a narrow palleal
impression strongly sinuous behind. Inhabits the sea at Jamaica and
shores of America. Nine species.

 Sanguinolaria occidens.
 S. rosea.
 S. alba.
 S. livida.
 S. rugosa.

        ·       ·       ·       ·       ·

 S. fusca.*
 S. lusoria.*
 S. Nuttallii.*
 S. Californiana.*


                     2. Genus _Psammobia_. Pl. VII.

_Animal._ Unknown.

Resembling the Tellina, from which it was taken, but not having an
irregular plait on the anterior part.

_Shell._ Transverse, oblong-ovate, or elliptical, flattened, slightly
gaping at one side; summits projecting; hinge formed by two primary
teeth in the left valve, and one in the opposite one Inhabits the
European and American seas. Twenty-one species.

 Psammobia virgata.
 P. ferroensis.
 P. vespertina.
 P. muculosa.
 P. alba.
 P. Cayennensis.
 P. lævigata.
 P. Tellinella.
 P. cærulescens.
 P. elongata.
 P. flavicans.
 P. squamosa.
 P. pulchella.
 P. aurantia.
 P. fragilis.
 P. livida.
 P. galathea.

        ·       ·       ·       ·       ·

 P. lusoria.*
 P. fusca.*
 P. Pacifica.*
 P. Florida.*


                     3. Genus _Psammotæa_. Pl. VII.

_Animal._ Unknown.

_Shell._ Of the same form as the Psammobia, but differing in the number
of teeth, the left valve of the Psammotæa having only one tooth; and
sometimes one valve is without teeth, while the other has two; ligament
exterior, attached to callosities at the hinge, and without an irregular
plait. Inhabits the Australian seas. Seven species. One fossil species.

 Psammotæa violacea.
 P. zonalis.
 P. pellucida.
 P. candida.
 P. tarentina.
 P. donacina.
 P. serotina.

N. TELLINARIA. Seven Genera.

The two last of these genera have no lateral teeth, the rest have one or
two.


                      4. Genus _Tellina_. Pl. VII.

_Animal._ Body triangular, much compressed: the free edge of the mantle
furnished with a row of tentacular, largest and longest in the rear;
foot very large, compressed and pointed to the front; buccal appendages
nearly as large as the bronchial laminæ, of which the external pair are
much smaller than the internal; the anterior contractile muscle larger
than the other; tubes very distinct.

_Shell._ Of a somewhat variable form, generally striated longitudinally
and much compressed, equivalved, more or less inequilateral; the
anterior side almost always longer and more rounded than the posterior,
which constantly presents a flexuous fold, at least at its inferior
edge; summits feebly marked; hinge similar; one or two cardinal teeth;
two lateral teeth, far apart with a pit at their base in each valve;
ligament posterior, large; round muscular impressions. The finest
species of this beautiful shell are found in the pearl fisheries of
Ceylon; and numerous species on the American shore. Sixty-eight species.

 Tellina unimaculata.
 T. virgata.
 T. semizonalis.
 T. staurella.
 T. lutirostra.
 T. rostrata.
 T. Spengleri.
 T. radiata.
 T. crucigera.
 T. elliptica.
 T. albinella.
 T. rosea.
 T. foliacea.
 T. operculata.
 T. chloraleuca.
 T. remies.
 T. sulcata.
 T. crassa.
 T. exilis.
 T. donacina.
 T. nitida.
 T. striatula.
 T. decussata.
 T. obliqua.
 T. nymphalis.
 T. capsoides.
 T. seradiata.
 T. margaritina.
 T. strigosa.
 T. planata.
 T. depressa.
 T. pulchella.
 T. fabula.
 T. tenuis.
 T. sulphurea.
 T. cornuta.
 T. iris.
 T. levigata.
 T. linguafelis.
 T. rugosa.
 T. lacunosa.
 T. gargadia.
 T. pristis.
 T. gigas.
 T. scalaris.
 T. psammotella.
 T. scobinata.
 T. Brasiliana.
 T. umbonella.
 T. deltoidalis.
 T. multangula.
 T. solidula.
 T. polygona.

        ·       ·       ·       ·       ·

 T. ostracea.*
 T. intastriata.*
 T. polita.*
 T. tenera.*
 T. flexuosa.*
 T. secta.*
 T. decorate.*
 T. lateralis.*
 T. alternata.*
 T. vimaculata.*
 T. pumicea.*
 T. alta.*
 T. nasuta.*
 T. lineata.*
 T. sordida.*


                    5. Genus _Tellinides_. Pl. VII.

_Animal._ As above.

This genus is very nearly allied to the Psammobia, Tellina, and Lucina,
but upon close examination it will be found to be distinct from either.

_Shell._ Equilateral, transverse, somewhat elongated, nearly without the
flexuous plait; two divergent cardinal teeth, of which the anterior is
but little distant from the summit. Inhabits the Bay of Naples. Two
species. One species is found on the shores of America.

 Tellinides Timorensis.

        ·       ·       ·       ·       ·

 T. rosea.*


                      6. Genus _Corbis_. Pl. VII.

_Animal._ Differing slightly from the Lucina.

This genus was classed by Lamarck with the Lucina, but the great
difference in the organization of the animals discovered by Cuvier, has
made this a distinct genus.

_Shell._ Equivalve, transverse, without any irregular fold on the
anterior margin, having the beaks flexed inward and opposite; two
cardinal teeth; two lateral, the posterior of which is nearest the
hinge; muscular impressions simple, ligament external. Inhabits the
Indian Ocean.

 Corbis fimbriata.
 C. maculata.


                      7. Genus _Lucina_. Pl. VII.

_Animal._ Very imperfectly known.

_Shell._ Inequilateral, suborbicular, beaks small, pointed, and oblique;
two divergent cardinal teeth, one of which is bifid, and which vary or
disappear with age; two lateral teeth sometimes obsolete, the posterior
approaches nearest to the cardinal teeth; two muscular impressions far
apart, the posterior in shape of a band, sometimes very long; ligament
external. Inhabits the British and American seas. Twenty-six species.

 Lucina Jamaicensis.
 L. edentula.
 L. radula.
 L. lactea.
 L. circinaria.
 L. columbella.
 L. mutabilis.
 L. squamosa.
 L. Peruviana.
 L. fimbriata.
 L. undata.
 L. divaricata.
 L. scabra.
 L. sinuata.
 L. lutea.
 L. globularis.
 L. digitalis.
 L. Pecten.
 L. reticulata.
 L. carmaria.
 L. concentrica.

        ·       ·       ·       ·       ·

 L. bella.*
 L. Pennsylvania.*
 L. sphæroides.*
 L. Californica.*
 L. Nuttallii.*


                       8. Genus _Donax_. Pl. VII.

_Animal._ As in Tellina.

_Shell._ Transverse, inequilateral, equivalve; anterior side short and
obtuse; two primary teeth in one or both valves; one or two lateral
teeth varying in distance; two round muscular impressions; ligament,
external, short, and inserted at the posterior impression. Inhabits the
seas of Europe and America. Thirty-one species.

 Donax pubescens.
 D. cuneata.
 D. radians.
 D. abbreviata.
 D. ringens.
 D. Cayennensis.
 D. denticulata.
 D. cinatina.
 D. cardioides.
 D. scorta.
 D. compressa.
 D. columbella.
 D. Australis.
 D. bicolor.
 D. merois.
 D. scripta.
 D. trunculata.
 D. fiabagella.
 D. Martiniænsis.
 D. triquetra.
 D. rugosa.
 D. elongata.
 D. deltoides.
 D. veneriformis.
 D. Vittata.
 D. granosa.
 D. epidermia.
 D. minima.

        ·       ·       ·       ·       ·

 D. variabilis.*
 D. fossar.*
 D. Californica.*


                       9. Genus _Capsa_. Pl. VII.

_Animal._ As above.

_Shell._ Transverse, equivalve, valves approximate and close; three
primary teeth in the right valve, and a single bifid tooth in the left,
inserted into a cavity in the opposite one; no lateral teeth; ligament
external and on the short side, as in Donax, from which it was separated
by Lamarck, on account of the peculiarity of the hinge, inhabits the
Indian Ocean. Three species.

 Capsa levigata.
 C. Braziliensis.
 C. Donaoides.


                     10. Genus _Crassina_. Pl. VII.

_Animal._ As above.

_Shell._ Distinguished from the Venus by having only two teeth on each
valve, and from the crasatella by the position of the ligament; solid,
suborbicular, thick, hinge with two strong diverging primary teeth in
the right valve, and two unequal ones on the other; ligament external.
Inhabits the Scottish and Devonshire coasts. One species.

 Crassina Danmoniensis.


                               FAMILY IX.

                        CONCHACEA. Seven Genera.

This family is divided into _Conchæ Marinæ_, and _Conchæ Fluviatiles_.


                      CONCHÆ MARINÆ. Four Genera.


                         1. _Cyprina._ Pl. VII.

_Animal._ Thick, oval, foot compressed, falciform, geniculated mantle
closed behind, and pierced by two oval apertures with cirrous edges: no
veritable tubes.

_Shell._ With epidermis; thick, regular, substriated longitudinally,
sub-cordiform, equivalved, inequilateral; summits strongly flexed to the
front and often contiguous; hinge thick, subsimilar, formed by three
slightly converging cardinal teeth, and by a posterior lateral tooth,
sometimes obsolete; ligament very thick; muscular impressions distant,
subcircular, and united by a narrow marginal band. Inhabits the Atlantic
Ocean and British seas. Two living species. Seven fossil.

 Cyprina tennistria.
 C. Icelandica.


                     2. Genus _Cytherea_. Pl. VII.

_Animal._ Oval or round, generally but little compressed; edges of the
mantle undulous, and garnished with tentacular cirri in one row; foot
considerable, compressed, trenchant, in other respects diversiform;
tubes tolerably elongated, and most usually united; mouth small; labial
appendages quite small; branchiæ wide, short, free, or not united either
with one another or with those of the opposite side.

_Shell._ Solid, equivalve, regular, inequilateral; summits equal,
reflexed, and slightly projecting; four primary teeth on one valve, of
which three are divergent, and approximating at the base, and one
remote—this circumstance easily distinguishing it from the Venus. On the
other valve are three primary divergent teeth with a distant cavity
parallel with the edge. Inhabits the British, Mediterranean, and
American seas. Eighty-three living species. Nine fossil.

 Cytherea petechialis.
 C. morphina.
 C. Castanea.
 C. casta.
 C. lusoria.
 C. graphica.
 C. impudica.
 C. purpurata.
 C. zonaria.
 C. tigrina.
 C. pulicaris.
 C. numulina.
 C. abbreviata.
 C. pectinata.
 C. flexuosa.
 C. ranella.
 C. lunularis.
 C. divaricata.
 C. corbicula.
 C. meretrix.
 C. tripla.
 C. erycina.
 C. impar.
 C. Guiniensis.
 C. pectoralis.
 C. Arabica.
 C. Florida.
 C. immaculata.
 C. Chione.
 C. hepatica.
 C. citrina.
 C. lactea.
 C. lata.
 C. lincta.
 C. trigonella.
 C. prostrata.
 C. Hebræa.
 C. tigerina.
 C. ornata.
 C. umbonella.
 C. castrensis.
 C. picta.
 C. scripta.
 C. mixta.
 C. muscaria.
 C. plicatina.
 C. dentaria.
 C. nodulosa.
 C. cuneata.
 C. lunaris.
 C. placunella.
 C. cygnus.
 C. juvenilis.
 C. gigantea.
 C. Venetiana.
 C. lilacina.
 C. rufa.
 C. erycinella.
 C. Dione.
 C. planatella.
 C. trimaculata.
 C. nitidula.
 C. pellucida.
 C. maculata.
 C. lucinalis.
 C. albina.
 C. exoleta.
 C. mactroides.
 C. concentrica.
 C. sulcatina.
 C. interrupta.
 C. punctata.
 C. undatina.
 C. gibbia.
 C. macrodon.
 C. testudinalis.
 C. rugifera.
 C. aspergata.
 C. squamosa.
 C. cardilla.

        ·       ·       ·       ·       ·

 C. occulta.*
 C. callosa.*
 C. crassatelloides.*


                       3. Genus _Venus_. Pl. VII.

_Animal._ As above.

_Shell._ Solid, thick, regular, perfectly equivalved and close, more or
less inequilateral; summits well marked and inclined to the front; hinge
subsimilar; the middle cardinal tooth forked, or three cardinal teeth
more or less contiguous and convergent towards the summits; ligament
thick, often arcuated, convex, exterior; two distant muscular
impressions; cordiform depressions beneath the beaks. Inhabits the
British and American seas. One hundred living species. Nine fossil.

 Venus reticulata.
 V. rugosa.
 V. corbis.
 V. crebiscula.
 V. discina.
 V. cancellata.
 V. marica.
 V. sulcaria.
 V. cardivides.
 V. texturata.
 V. elliptica.
 V. rariflamma.
 V. mercenaria.
 V. pullastra.
 V. gallina.
 V. truncata.
 V. pectinula.
 V. anomala.
 V. lamellata.
 V. exilis.
 V. rufa.
 V. Scotica.
 V. hiantina.
 V. virginea.
 V. corugata.
 V. ovulæa.
 V. papilionacea.
 V. callipyga.
 V. punctifera
 V. nebulosa
 V. literata
 Venus floridella.
 V. aphrodina.
 V. pulchella.
 V. aphrodinoides.
 V. tristis.
 V. flammea.
 V. puerpera.
 V. verrucosa.
 V. pygmæa.
 V. casina.
 V. crenulata.
 V. plicata.
 V. granulata.
 V. pectorina.
 V. cingulata.
 V. textilis.
 V. grisea.
 V. geographica.
 V. Dombeii.
 V. decussata.
 V. lagopus.
 V. glandina.
 V. gallinula.
 V. retifera.
 V. sulcata.
 V. galactites.
 V. exalbida.
 V. scalarina.
 V. dorsata.
 V. aurea.
 V. crassisulca.
 V. carneola.
 V. petalina.
 V. cornularis.
 V. adspersa.
 V. opima.
 V. turgida.
 V. flammiculata.
 V. strigosa.
 V. Perronii.
 V. elegantina.
 V. undulosa.
 V. vermiculosa.
 V. vulvina.
 V. marmorata.
 V. Malabarica.
 V. laterisulca.
 V. subrostrata.
 V. phaseolina.
 V. Florida.
 V. bicolor.
 V. catenifera.
 V. sinuosa.
 V. rimularis.
 V. ovata.
 V. pumila.
 V. inquinata.

        ·       ·       ·       ·       ·

 V. notata.*
 V. præparea.*
 V. elevata.*
 V. inequalis.*
 V. castanea.*
 V. Nuttallii*
 V. staminea.*
 V. Californica.*
 V. lamellifera.*
 V. Mortoni.*


                   4. Genus _Venericardia_. Pl. VII.

_Animal._ Nearly as above.

_Shell._ Suborbicular, inequilateral, equivalve, sides having usually
longitudinally rayed ribs; hinge with two oblique cardinal teeth in each
valve, turned in the same direction. Five living species. Ten fossil
species.

 Venericardia Australis.
 V. imbricata.
 V. flammea.
 V. Tankervillii.
 V. crassicosta.


                   CONCHÆ FLUVIATILES. Three Genera.


                      5. Genus _Cyclas_. Pl. VII.

_Animal._ Body oval, thick; edges of the mantle simple; tubes short and
united; foot wide, compressed at base, and terminated by a sort of leg
or appendage.

The shells of this genus are very small, found buried in the mud of
fresh waters; summits never eroded, but some species are so thin as to
be transparent.

_Shell._ With an epidermis, oval, or suborbicular, regular, equivalved,
inequilateral; summits obtuse, contiguous or turned anteriorly; hinge
similar, complex, formed by a slightly variable number of cardinal
teeth, and by two separated lateral teeth with a pit at the base;
ligament exterior, posterior, and inflated; two distant muscular
impressions, united by a faintly marked abdominal band, and without
posterior excavation. Fifteen species.

 Cyclas cornea.
 C. obliqua.
 C. obtusalis.
 C. Australis.
 C. striatina.
 C. rivicola.
 C. lacustris.
 C. calyculata.
 C. fontinalis.
 C. sulcata.

        ·       ·       ·       ·       ·

 C. Sarratogea.*
 C. Rhomboidea.*
 C. similis.*
 C. Partumeia.*
 C. dubia.*


                      6. Genus _Cyrena_. Pl. VII.

_Animal._ As above.

_Shell._ Rounded and trigonal, ventricose, inequilateral; hinge with
three teeth on each valve; two lateral teeth, one of which is near the
primary ones; ligament exterior, situated on the largest side. The
apices are always eroded or carious in shells of this genus. Inhabits
the rivers of China. One is found on the coast of Carolina. Ten living
species. One fossil.

 Cyrena orientalis.
 C. depressa.
 C. fuscata.
 C. violacea.
 C. Ceylonica.
 C. trigonella.
 C. cor.
 C. fluminea.
 C. Bengalensis.

        ·       ·       ·       ·       ·

 C. Caroliniensis.*


                     7. Genus _Galathea_. Pl. VII.

_Animal._ As above.

_Shell._ Equivalve, subtrigonal, covered with a greenish epidermis; the
surface beneath is white, with several violet streaks radiating from the
summit to the margin; two furrowed cardinal teeth upon one valve, three
upon the other, the middle one being largest and callous; muscular
impressions double and lateral. Inhabits the rivers of Ceylon. One
species.

 Galathea radiata.


                               FAMILY X.

                        CARDIACEA. Five Genera.


                      1. Genus _Cardium_. Pl. VII.

_Animal._ Body somewhat inflated; mantle edged with tentacular cirri in
all its inferior part; tubes united, of moderate size, and provided with
cirri at the extremity; mouth transverse, very wide, with moderate
labial appendages; foot very large, cylindrical, somewhat inclined
anteriorly; branchiæ thick, rather small, especially the external
laminæ: the internal united in all their extent.

_Shell._ Inflated, equivalve, sub-cordiform (when viewed anteriorly,
usually costated from the apex to the circumference); summits very
evident, but slightly flexed to the front; hinge complex, similar,
formed of two oblique, conical cardinal teeth, and of two distant
lateral teeth, upon each valve; ligament dorsal, posterior and very
short. Inhabits the European and American seas. Fifty-seven living
species. Fourteen fossil.

 Cardium indicum.
 C. Asiaticum.
 C. fimbriatum.
 C. aculeatum.
 C. tuberculatum.
 C. apertum.
 C. bullatum.
 C. echinatum.
 C. biradiatum.
 C. pectinatum.
 C. isocardium.
 C. angulatum.
 C. serratum.
 C. costatum.
 C. ringens.
 C. tennicostatum.
 C. psudolima.
 C. crinaceum.
 C. Basilianum.
 C. papyraceum.
 C. ciliare.
 C. levigatum.
 C. eolicum.
 C. elongatum.
 C. rugosum.
 C. unedo.
 C. medinum.
 C. tumotiferum.
 C. retusum.
 C. rusticum.
 C. Greendlandicum.
 C. crenulatum.
 C. minotum.
 C. scobinatum.
 C. cardissum.
 C. inversum.
 C. ventricosum.
 C. obtusum.
 C. fragum.
 C. lineatum.
 C. edule.
 C. latum.
 C. exigunum.
 C. rosenum.
 C. hemicardium.
 C. Junoniæ.
 C. muricatum.
 C. marmoreum.
 C. sulcatum.
 C. cifidium.

        ·       ·       ·       ·       ·

 C. Mortonii.*
 C. substriatum.*
 C. Nuttallii.*
 C. Californianum.*
 C. quadragenarium.*
 C. Pennulatum.*
 C. pubescens.*


                      2. Genus _Cardita_. Pl. VII.

_Animal._ Body suborbicular, terminated superiorly by a sort of hook;
mantle but little open; foot terminated at its extremity by a part much
narrower than the base; superior lobes of the branchiæ very short.

_Shell._ Thick, solid, equivalve, more or less inequilateral; summit
dorsal always much flexed anteriorly; hinge similar, formed by two
oblique teeth, one short, cardinal or apicial, the other postapicial,
long, lamellous and arcuated; ligament elongated, subexterior and
inserted; two very distinct muscular impressions, united by a palleal
band, narrow and semicircular. Inhabits the Mediterranean and American
seas. Twenty-three living species. Four fossil.

 Cardita Ajar.
 C. squamosa.
 C. crassicosta.
 C. calyculata.
 C. nodulosa.
 C. trapezia.
 C. sulcata.
 C. turgida.
 C. phrenetica.
 C. rufescens.
 C. subaspera.
 C. intermedia.
 C. depressa.
 C. sinuata.
 C. citrina.
 C. orbularis.
 C. bicolor.
 C. concamerata.
 C. aviculina.
 C. sublevigata.
 C. lithophagella.

        ·       ·       ·       ·       ·

 C. borealis.*
 C. incrassata.*


                    3. Genus _Cypricardia_. Pl. VII.

_Animal._ As above.

_Shell._ Obliquely elongated, equivalve, inequilateral; valves striated,
not ribbed; distinguished from the Cardita by having three teeth beneath
the apices, and a callous lengthened tooth or ridge. Inhabits the coast
of Guinea and California. Five living species. Three fossil.

 Cypricardia angulata.
 C. Guinaica.
 C. coralliophaga.
 C. rostrata.

        ·       ·       ·       ·       ·

 C. Californica.*


                     4. Genus _Hiatella_. Pl. VII.

_Animal._ Unknown.

_Shell._ Thin, elongated, subrhomboidal, equivalve, very inequilateral,
gaping at its inferior edge, and at its posterior extremity; summit very
anterior, and much flexed to the front; hinge formed of a single tooth
upon one valve corresponding to an emargination in the opposite valve,
or of a small tooth with a cardinal pit upon each valve; ligament
exterior and dorsal. Inhabits the British seas. Two species.

 Hiatella Arctica.
 H. biaperta.


                    5. Genus _Isocardia_. Pl. VIII.

_Animal._ Body very thick: edges of the mantle finely papillaceous,
separated inferiorly, and united behind by a transverse band, pierced
with two orifices surrounded with radiating papillæ; foot small,
compressed, trenchant.

_Shell._ Free, regular, inflated, equivalve, very inequilateral, with
diverging summits, strongly flexed anteriorly and outwardly, in a
commencing spiral, hinge dorsal, long, similar, formed of two flat
cardinal teeth and one lamellous behind the ligament; ligament dorsal,
exterior, diverging anteriorly towards the summit; muscular impressions
very distant and small. Inhabits the Mediterranean and British seas.
Four living species. One fossil.

 Isocardia Moltikana.
 I. retusum.
 I. cor.
 I. semisulcata.


                               FAMILY XI.

                         ARCACEA. Four Genera.


                       1. Genus _Arca_. Pl. VIII.

_Animal._ Body thick, slightly variable in form; abdomen provided with a
pedunculated foot, compressed, fit for adhesion, and cleft throughout
its extent; mantle supplied with a simple row of cirri and slightly
prolonged posteriorly; buccal tentacula very small and very thin.

_Shell._ Somewhat diversiform, but most usually elongated and more or
less oblique at the posterior extremity, often very inequilateral;
summits more or less distant and little flexed to the front; hinge
anomalous, straight, or a little flexed, long, and formed by a line of
short vertical teeth, decreasing from the extremities to the centre;
ligament exterior, wide, nearly as much before as behind the summit; two
muscular impressions united by a band or palleal impression, not very
distinct. Inhabits the American and British seas. Forty-one living
species. Nine fossil.

 Arca semitorta.
 A. tetragona.
 A. sinuata.
 A. cardissa.
 A. retusa.
 A. ovata.
 A. scapha.
 A. fusca.
 A. Domingensis.
 A. trapezina.
 A. inequivalvis.
 A. tortuosa.
 A. Noæ.
 A. umbonata.
 A. avellana.
 A. ventricosa.
 A. sulcata.
 A. Helbingii.
 A. barbata.
 A. Magellanica.
 A. pisolina.
 A. callifera.
 A. bisulcata.
 A. senilis.
 A. auriculata.
 A. Cayennensis.
 A. antiquata.
 A. Braziliana.
 A. lactea.
 A. cancellaria.
 A. irudina.
 A. rhombea.
 A. corbicula.
 A. Indica.
 A. granosa.
 A. squamosa.
 A. pistachia.

        ·       ·       ·       ·       ·

 A. ponderosa.*
 A. pexata.*
 A. incongrua.*
 A. transversa.*


                     2. Genus _Cucullæa_. Pl. VIII.

_Animal._ As above.

_Shell._ Trapeziform, inequilateral, equivalve, heart-shaped; beaks far
apart, separated by the angular groove of the ligament, which is
altogether external; hinge linear, straight, with small transverse
teeth, having at its extremity from two to five parallel ribs; valves
minutely striated longitudinally; margins crenulated. The Cucullæa is
distinguished from the Arca by the muscular impression, to one side of
which is an auriform testaceous appendage; the shell also is more
trapeziform. Inhabits the Indian ocean. One living species. One fossil.

 Cucullæa auriculifera.


                   3. Genus _Pectunculus_. Pl. VIII.

_Animal._ Body round, more or less compressed; mantle without cirri or
tubes; foot securiform, cleft at its inferior anterior edge; buccal
appendages linear.

_Shell._ Orbicular, equivalve, subequilateral; summit nearly vertical,
and more or less distant; hinge formed upon each valve, of a numerous
series of small teeth disposed in a curved line, sometimes interrupted
beneath the summit; ligament as in Arca, but usually much narrower.
Inhabits the British and Mediterranean seas. Twenty-two living species.
Nine fossil.

 Pectunculus pilosus.
 P. marmoratus.
 P. Pennaceus.
 P. castaneus.
 P. angulatus.
 P. palleus.
 P. zonalis.
 P. glycimeris.
 P. undulatus.
 P. scriptus.
 P. stellatus.
 P. violacescens.
 P. aggregatus.
 P. striatularis.
 P. pectinatus.
 P. rubeus.
 P. pectiniformis.
 P. nummarius.
 P. radiatus.
 P. vitreus.
 P. inscriptus.
 P. cinerosus.


                      4. Genus _Nucula_. Pl. VIII.

_Animal._ Body subtriquetral; mantle open in its inferior half only,
with whole edges, denticulated throughout the extent of the back,
without posterior prolongation; foot very large, thin at the root,
enlarged into a wide oval disk, the edges of which are furnished with
tentacular digitations; anterior buccal appendages, pretty long,
pointed, stiff, and applied one against the other like jaws; the
posterior ones also stiff and vertical.

_Shell._ More or less thick, subtriquetral, equivalved, inequilateral,
with summits contiguous and inclined anteriorly; hinge similar, formed
by a numerous series of very sharp teeth, pectinated and arranged in a
line interrupted under the summit; ligament internal, short, inserted in
a little oblique pit in each valve; two muscular impressions. Inhabits
the British and American seas. Forty-five living species. Four fossil.

 Nucula lanceolata.
 N. pella.
 N. obliqua.
 N. elongata.
 N. tellinoides.
 N. crenifera.
 N. Arctica.
 N. curvirostra.
 N. glacialis.
 N. fluviatilis.
 N. minuta.
 N. para.
 N. Mauritania.
 N. rostrata.
 N. Nicobarica.
 N. Margaritacea.
 N. Costellata.
 N. gibbosa.
 N. eburnea.
 N. polita.
 N. nasuta.
 N. fabula.
 N. Elenensis.
 N. cuneata.
 N. striata.
 N. rugulosa.
 N. Limatula.
 N. lævis.
 N. concentrica.
 N. decussata.
 N. exigua.
 N. squamosa.
 N. gigantea.
 N. nitida.
 N. tenuis.
 N. convexa.
 N. Pisum.
 N. carinifera.
 N. torta.
 N. plicaria.

        ·       ·       ·       ·       ·

 N. navicularis.*
 N. tenuisulta.*
 N. proxima.*
 N. acuta.*
 N. myalis.*


                              FAMILY XII.

                        TRIGONACEA. Two genera.


                     1. Genus _Trigonia_. Pl. VIII.

_Animal._ Entirely unknown.

_Shell._ Subtrigonal or suborbicular, thick, regular, equivalve,
inequilateral; summits but slightly prominent, little flexed,
anterodorsal; hinge complex, dorsal, dissimilar; two thick oblong teeth
joined angularly under the summit, strongly furrowed upon the right
valve, penetrating into two excavations of the same form, also furrowed,
in the left valve; ligament postapicial; two distinct muscular
impressions, not united by a band. Inhabits the Australian seas. One
living species. Fifteen fossil.

 Trigonia pectinata.


                     2. Genus _Castalia_. Pl. VIII.

_Animal._ Body large, slightly compressed, or moderately thick, more or
less oval; mantle with thick edges, simple or broken, open in all its
circumference except towards the back a kind of small, incomplete tube,
furnished with two rows of somewhat elongated cirri for the respiratory
cavity; flamelliform and trenchant.

_Shell._ Subtrigonal, equivalve, inequilateral; umbones eroded, covered
with epidermis, and flexed anteriorly; hinge with two lamellar teeth
transversely striated, one distant, posterior and shortened, the other
anterior, long, and lateral; ligament exterior. Habitation unknown. One
species.

 Castalia ambigua.


                              FAMILY XIII.

                         NAIADEA. Four genera.


                       1. Genus _Unio_. Pl. VIII.

_Animal._ See _Castalia_.

_Shell._ Usually very thick, nacred within, covered with epidermis,
corroded at the summits, which are dorsal and subanterior; dorsal hinge
formed by a double precardinal tooth, more or less compressed,
irregularly dentated on the left valve, and simple on the right,
together with a long lamellous tooth under the ligament: ligament
external, dorsal, and postapicial; two muscular impressions, well
marked, besides those of the retractile muscles. The species of this
genus grow more numerous daily; they are found in all countries, but
particularly in North America. One hundred and sixty-seven defined
species. Numerous fossil.

 Unio Batayus.
 U. crassissimus.
 U. elongatus.
 U. litoralis.
 U. pictorum.
 U. platyrhynchus.
 U. marginalis.
 U. tigris.
 U. Egyptiacus.
 U. Niloticus.
 U. Leaii.
 U. crassidens.
 U. obliquus.
 U. plicatus.
 U. purpuratus.
 U. radiatus.
 U. rectus.
 U. retusus.
 U. rotundatus.
 U. Australis.
 U. Nova Hollandica.

The following species are American:

 Unio Bengalensis. _Lea._
 U. bilineatus. „
 U. lamellatus. _Lea._
 U. Morchisonianus. „
 U. cæruleus. _Lea._
 U. corrugatus. „
 U. Corrianus. „
 U. Graianus. „
 U. alatus. „
 U. andontoides. „
 U. Augustatus. „
 U. apiculatus. „
 U. arcæformis. „
 U. arctior. „
 U. asperimus. „
 U. asper. „
 U. Blandingianus. „
 U. Barnesianus. „
 U. brevidens. „
 U. camelus. „
 U. capsæformis. „
 U. carbonarius. „
 U. castanus. „
 U. Claibornensis. „
 U. circulus. „
 U. occineus. „
 U. compressus. „
 U. complanatus. „
 U. confertus. „
 U. congaræus. „
 U. contradens. „
 U. Cooperianus. „
 U. creperus. „
 U. cuprinus. „
 U. Cumberlandicus. „
 U. decisus. „
 U. dolabriformis. „
 U. donaciformis. „
 U. Dorfeuillianus. „
 U. uromas. „
 U. ebenus. „
 U. elegans. „
 U. olivarus. _Lea._
 U. ponderosus. „
 U. divaricatus. „
 U. acutissimus. „
 U. fabalis. „
 U. Fisherianus. „
 U. folliculatus. „
 U. fulvus. „
 U. gibber. „
 U. glaber. „
 U. glans. „
 U. globosus. „
 U. graniferus. „
 U. Griffithianus. „
 U. Haysianus. „
 U. heterodon. „
 U. Hildrethianus. „
 U. Hopetonensis. „
 U. Hydianus. „
 U. inflatus. „
 U. interruptus. „
 U. iris. „
 U. irroratus. „
 U. Jayensis. „
 U. jegunus. „
 U. Katherinæ. „
 U. Kirklandianus. „
 U. lævissimus. „
 U. lacrymosus. „
 U. lancolatus. „
 U. Lecontianus. „
 U. lens. „
 U. lugubris. „
 U. luteolus. „
 U. Medellinus. „
 U. Menkianus. „
 U. metanever. „
 U. Mühlfeldianus. „
 U. ellipsis. _Lea._
 U. multiradiatus. „
 U. modiolioformis. „
 U. notatus. „
 U. Novi-Eboraci. „
 U. obesus. „
 U. obscurus. „
 U. occidens. „
 U. palliatus. „
 U. patulus. „
 U. stapes. „
 U. perdix. „
 U. perplexus. „
 U. pictus. „
 U. pileus. „
 U. pliciferus. „
 U. pulcher. „
 U. pumilis. „
 U. pustulatus. „
 U. pustulosus. „
 U. pyramidatus. „
 U. Rangianus. „
 U. Ravenelianus. „
 U. Roanokensis. „
 U. rubiginosus. „
 U. Schoolcraftensis. „
 U. securis. „
 U. Shepardianus. „
 U. simus. „
 U. solidus. „
 U. Sowerbianus. „
 U. spinosus. „
 U. splendidus. „
 U. multiplicatus. _Lea._
 U. subovatus. „
 U. subrotundus. „
 U. sulcatus. „
 U. Taitianus. „
 U. Tampicoensis. „
 U. Tappanianus. „
 U. tenuissimus. „
 U. trapezoides. „
 U. trigonus. „
 U. Troostensis. „
 U. turgidus. „
 U. Vanuxemensis. „
 U. varicosus. „
 U. Vaughanianus. „
 U. venustus. „
 U. Watercensis. „
 U. Zeiglerianus. „
 U. zigzag. „
 U. alatus. _Say._
 U. apiculatus. „
 U. camptodon. „
 U. cariosus. „
 U. crassus. „
 U. cylindricus. „
 U. declivis. „
 U. dehiscens. „
 U. monodontus. „
 U. nasutus. „
 U. ovatus. „
 U. personatus. „
 U. subtentus. „
 U. tetralasmus. „


                      2. Genus _Hyria_. Pl. VIII.

_Animal._ As above.

_Shell._ Solid, nacred, equivalve, obliquely triangular, auriculated;
base straight and truncated; hinge with two projecting teeth, the
cardinal divided into numerous radiations, anterior ones smaller, the
others lamellar and long. Inhabits the lakes and rivers of America. Two
species.

 Hyria avicularis.*
 Hyria corrugata.*

NOTE.—_Alasmidonta._ Separated by Say from the Anodonta by its primary
tooth, and from the Unio by being destitute of the lamelliform teeth.

_Shell._ Transverse, equivalve, inequilateral; hinge with a primary
tooth in each valve; cicatrices three. Four species.

 Alasmidonta undulata.
 A. ambigua.
 A. marginata.
 A. confragosa.


                     3. Genus _Anodonta_. Pl. VIII.

_Animal._ As above.

_Shell._ Rather thin, regular, close, equivalve, inequilateral; summit
anterodorsal; hinge entirely without teeth, with a postapicial lamina;
ligament external, dorsal, and postapicial, two well marked muscular
impressions, besides those of the retractile muscles. Inhabits
fresh-water lakes in Europe and America. Forty-nine living species; and
many fossil.

 Anodonta areolatus.
 A. marginata.
 A. rubens.
 A. anatina.
 A. fragilis.
 A. trapezialis.
 A. rufa.
 A. uniopsis.
 A. intermedia.
 A. glauca.
 A. anatina.
 A. sinuosa.
 A. Patagonica.
 A. cygnæa.
 A. sulcata.
 A. cataracta.
 A. exotica.
 A. crispata.
 A. Pennsylvanica.
 A. maximus.

The following species are American.

 Anodonta magnifica. _Lea._
 A. Woodiana. „
 A. angulata. „
 A. Benedictensis. „
 A. cylindracea. „
 A. decora. „
 A. edentula. „
 Anodonta gigantea. _Lea._
 A. incerta. „
 A. Pepiniana. „
 A. plana. „
 A. salmonia. „
 A. Stewartiana. „
 A. subcylindracea. „
 A. Ferussacina. _Lea._
 A. fluviatilis. „
 A. Newtonensis. „
 A. Nuttalliana. „
 A. Oregonensis. „
 A. ovata. „
 A. pavonia. „
 A. Wahlamatensis. „
 A. Wardiana. „
 A. gibbosa. _Say._
 A. grandis. „
 A. impura. „
 A. suborbiculata. „
 A. undulata. „
 A. lugubris. „


                     4. Genus _Iridina_. Pl. VIII.

_Animal._ As above.

The principal difference between the Anodonta and the Iridina, consists
in the tuberculated hinge of the latter.

_Shell._ Thin, oval, much elongated, inauriculated; hinge very long,
linear, and crenulated throughout its length, ligament external and
marginal; two distinct muscular impressions. Inhabits the Nile and
American coasts. Six species.

 Iridina exotica.
 I. Nilotica.

        ·       ·       ·       ·       ·

 I. cælistis.*
 I. rubens.*
 I. elongata.*
 I. McMurtria.*


                              FAMILY XIV.

                        CHAMACEA. Three genera.


                     1. Genus _Diceras_. Pl. VIII.

_Animal._

_Shell._ Inequivalve, adherent; beaks conical, very large, diverging in
irregular spiral contortions; hinge with a large, thick, concave,
subauricular tooth in the larger prominent valve; two muscular
impressions. One species. Fossil.

 Diceras arietina.


                      2. Genus _Chama_. Pl. VIII.

_Animal._ Body suborbicular terminated superiorly by a sort of hook;
mantle very slightly opened for the passage of a foot, terminated at its
extremity by a part much narrower than the base; superior lobes of the
branchiæ very short.

_Shell._ Irregular, adhering, inequivalve, inequilateral; summits more
or less twisted spirally, especially in the lower valve by which these
animals have the faculty of affixing themselves to other bodies; hinge
dissimilar, thick, formed by a single lamellous tooth arcuated,
subcrenulated, postcardinal and articulated in a furrow of the same
form; ligament anterior and postapicial; two large muscular impressions,
distant. British and American seas. Eighteen living species.

 Chama damæcornis.
 C. crenulata.
 C. arcinella.
 C. cristella.
 C. Lazarus.
 C. gryphoides.
 C. unicornis.
 C. radians.
 C. æruginosa.
 C. decussata.
 C. ruderalis.
 C. Japonica.
 C. limbula.
 C. asperella.
 C. albida.
 C. croceata.

        ·       ·       ·       ·       ·

 C. exogyra.*
 C. Florida.*


                     3. Genus _Etheria_. Pl. VIII.

_Animal._ Unknown.

_Shell._ Adhering, irregular, thick, much nacred, inequilateral,
inequivalve; summits subcephalic, thick, indistinct, in a species of
heel, growing longer with age; hinge without teeth, callous, irregular
and thick; ligament subdorsal in the exterior portion of the shell, and
prolonged to a point internally; two irregular oblong muscular
impressions, one superior and subposterior, the other inferior and
anterior, with a marginal palleal impression. Inhabits the Indian Ocean.
Five species.

 Etheria elliptica.
 E. trigonula.
 E. semilunata.
 E. transversa.
 E. Carteronii.


                               FAMILY XV.

                         TRIDACNEA. Two genera.


                     1. Genus _Tridacna_. Pl. VIII.

_Animal._ Body somewhat thick; edges inflated, lobes of the mantle
adhering, and united in nearly all their circumference, so as to present
but three apertures, the first inferior and anterior, for the egress of
the foot; the second superior and posterior for the bronchial cavity,
the third much smaller and in the middle of the dorsal edge; two pairs
of labial appendages, thin, nearly filiform, in the middle of which is a
very small buccal orifice; branchiæ long and narrow; abdominal muscular
mass considerable, and giving issue, as if from a cup, to a thick bundle
of byssoid muscular fibres.

_Shell._ Thick, solid, of variable size, regular, triangular,
inequilateral; summits inclined posteriorly, hinge dissimilar, entirely
anterior to the summit; a lamellous precardinal tooth and two distant
lateral teeth upon the left valve, corresponding with two precardinal
lamellous teeth, and one distant lateral tooth upon the right valve;
ligament anterior, elongated; a large, bifid, submedian muscular
impression; another anterior one smaller and less distinct. Inhabits the
Indian Ocean. Seven living species. One fossil.

 Tridacna gigas.
 T. squamosa.
 T. elongata.
 T. crocea.
 T. mutica.
 T. serrifera.
 T. pustulosa.


                     2. Genus _Hippopus_. Pl. VIII.

_Animal._ As above.

_Shell._ More elongated and inequilateral than in the _Tridacna_, the
anterior side being longer than the posterior; the posterior slope
closed with a dentated margin. Inhabits the Indian seas. One species.

 Hippopus maculatus.


                              FAMILY XVI.

                        MYTILACEA. Three genera.


                     1. Genus _Mytilus_. Pl. VIII.

_Animal._ Body oval, somewhat inflated; mantle open in its inferior half
only, and terminated posteriorly by an oval cleft with fringed edges; a
linguiform, canaliculated, abdominal appendage, with a byssus at its
base behind, and several pairs of retractile muscles; mouth with simple
lips; two contractile muscles, of which the anterior is very small.

_Shell._ Of a serrated tissue, elongated, more or less oval, sometimes
subtriangular, equivalve, summits anterior, more or less curved, sloping
inferiorly in a slight degree; hinge toothless, or with two very small
rudiments; ligament dorsal, linear, subinterior, inserted in a narrow
and very long furrow; two muscular impressions, of which the anterior is
very small, besides those of the retractile muscles. Inhabits the
British and American seas. Forty-two species.

 Mytilus erosus.
 M. decussatus.
 M. elongatus.
 M. Zonarius.
 M. violaceus.
 M. smaragdinus.
 M. edulis.
 M. Hesperianus.
 M. exustus.
 M. ovalis.
 M. Domingensis.
 M. Afer.
 M. ungularis.
 M. borealis.
 M. augustanus.
 M. lacunatus.
 M. incurvatus.
 M. abbreviatus.
 M. Magellicanus.
 M. crenatus.
 M. hirsutus.
 M. latus.
 M. ungulatus.
 M. opalus.
 M. corneus.
 M. retusus.
 M. perna.
 M. bilocularis.
 M. ustulatus.
 M. Senegalensis.
 M. achatinus.
 M. planulatus.
 M. Galloprovincialis.
 M. lineatus.
 M. canalis.
 M. sanguineus.

        ·       ·       ·       ·       ·
 M. hamatus.*
 M. croceus.*
 M. cubitus.*
 M. lateralis.*
 M. Californianus.*
 M. leucophœatus.*


                     2. Genus _Modiola_. Pl. VIII.

_Animal._ As above.

Separated by Lamarck from the Mytilus, on account of its being more
transverse than longitudinal, the beaks instead of being terminal are
placed beneath the apex.

_Shell._ Smooth, subtransverse, equivalve, regular, subtriangular,
posterior side short; summits nearly lateral; hinge toothless, linear
and lateral; ligament partly interior, situated in a marginal furrow;
one sublateral, elongated muscular impression in each valve. Inhabits
the British and American seas. Thirty-two species.

 Modiola Guyanensis.
 M. pulex.
 M. discors.
 M. cinnamorea.
 M. plicata.
 M. lithophaga.
 M. Adriatica.
 M. discrepans.
 M. trapezina.
 M. silicula.
 M. semen.
 M. lævigata.
 M. Papuana.
 M. tulipa.
 M. albicosta.
 M. vagina.
 M. picta.
 M. sulcata.
 M. plicatula.
 M. semifusca.
 M. purpurata.
 M. barbata.
 M. caudigera.
 M. squamosa.
 M. securis.

        ·       ·       ·       ·       ·

 M. Americana.*
 M. castanea*
 M. opifex.*
 M. capax.*
 M. recta.*
 M. Carolinensis.*
 M. semi-costata.*


                      3. Genus _Pinna_. Pl. VIII.

_Animal._ Body oval, elongated, moderately thick, enveloped in a mantle
closed above, open below, and especially to the rear, where it forms
sometimes a sort of tube furnished with tentacular cirri: a flabelliform
abdominal appendage, and a very considerable byssus; mouth provided with
double lips, beside two pairs of labial appendages; a single large
retractile muscle apparent.

_Shell._ Subcornate, fibrous, brittle, regular, equivalve, longitudinal,
triangular, pointed anteriorly, in which direction is the summit, which
is straight, wide, and frequently truncated posteriorly; hinge dorsal,
longitudinal, linear, toothless; ligament occupying nearly all the
dorsal edge of the shell; a single and very wide muscular impression
posteriorly; a trace of the anterior in the summit. Inhabits the
Mediterranean Sea. Fifteen species.

 Pinna rudis.
 P. seminuda.
 P. nobilis.
 P. marginata.
 P. pectinata.
 P. ingens.
 P. varicosa.
 P. flabellum.
 P. angustina.
 P. squamosa.
 P. muricata.
 P. saccata.
 P. dolabrata.
 P. vexillum.
 P. nigrina.


                              FAMILY XVII.

                        MALLEACEA. Five genera.


                    1. Genus _Crenatula_. Pl. VIII.

_Animal._ Unknown.

_Shell._ Irregular, much flattened, subrhomboidal, subequivalve, gaping
posteriorly; summit anterior; hinge longitudinal, dorsal, toothless;
ligament submultiple, or inflated from place to place, and inserted in a
series of round cavities corresponding with the dorsal edge; muscular
impression unique and subcentral. Inhabits the Red Sea. Seven species.

 Crenatula modiolaris.
 C. avicularis.
 C. nigrina.
 C. bicostalis.
 C. viridis.
 C. mytiloides.
 C. phasianoptera.


                      2. Genus _Perna_. Pl. VIII.

_Animal._ Body much compressed, the mantle prolonged posteriorly in a
sort of lobe, and fringed at its inferior edge only; a byssus; a single
contractile muscle.

_Shell._ Irregular, much compressed, subequivalve, form somewhat
variable, gaping at the anterior part of its inferior edge; summit very
small: hinge straight, vertical, buccal, toothless; ligament multiple,
and inserted in a series of longitudinal and parallel furrows; a
subcentral muscular impression. Inhabits the Indian seas. Ten species
living. Two fossil; one found in France and one in Virginia.

 Perna ephippium.
 P. isognomon.
 P. femoralis.
 P. marsupium.
 P. obliqua.
 P. sulcata.
 P. vulsella.
 P. nuclea.
 P. avicularis.
 P. canina.


                     3. Genus _Malleus_. Pl. VIII.

_Animal._ Imperfectly known, but certainly byssiferous, with a single
retractile muscle.

_Shell._ Subnacreous, irregular, subequivalve, inequilateral, generally
much auriculated anteriorly, and prolonged posteriorly into the body, so
as to present some resemblance to a hammer; summits entirely anterior;
between them and the inferior auricle, an oblique slope for the passage
of the byssus; hinge linear, very long, buccal, toothless; ligament
simple, triangular, inserted in a conical oblique pit, partly external;
a moderately large subcentral muscular impression. Inhabits the
Australian seas. Six species.

 Malleus normalis.
 M. vulgaris.
 M. albus.
 M. vulsellatus.
 M. anatinus.
 M. decurtatus.


                      4. Genus _Avicula_. Pl. IX.

_Animal._ Body much compressed; mantle cleft throughout its
circumference, except along the back, and garnished at its free edge
with a double row of very short tentacular cirri; foot small,
canaliculated; a byssus; mouth surrounded with fringed lips, besides two
pair of labial appendages, a large contractile muscle, nearly posterior.

_Shell._ Foliaceous or not; always nacred, subequivalve, of a subregular
form, but somewhat variable; valves oblique, the left one with a little
notch, through which the byssus passes; hinge linear, toothless, or with
two small rudimentary teeth; ligament more or less exterior, placed in a
narrow groove; one very large posterior muscular impression and one very
small anterior. Inhabits the British and American coasts. Nineteen
species.

 Avicula nudata.
 A. macroptera.
 A. semi-sagitta.
 A. falcata.
 A. Tarentina.
 A. squamulosa.
 A. Costellata.
 A. lotaria.
 A. heteroptera.
 A. crocea.
 A. Atlantica.
 A. papilionacea.
 A. physoides.
 A. virens.
 A. trigonata.
 A. phalænacea.

        ·       ·       ·       ·       ·

 A. hirundo.*
 A. pallida.*
 A. nebulosa.*


                     5. Genus _Meleagrina_. Pl. IX.

_Animal._ As above.

_Shell._ Subequivalve, rounded, squamous, a sinus posteriorly for the
passage of the byssus, at which place the left valve is notched and
narrow; hinge linear and destitute of teeth; ligament marginal,
elongated, partly exterior, and dilated in the centre. Inhabits the
Indian Ocean. Two species, of which the first is the pearl-oyster.

 Meleagrina margaritifera.
 M. albina.


                             FAMILY XVIII.

                        PECTINEA. Seven genera.


                       1. Genus _Pedum_. Pl. IX.

_Animal._ Unknown, but probably byssiferous.

_Shell._ Subtriangular, inequilateral, inequivalve, with rounded
summits, freely marked, unequal and distant: the right valve inflated,
widened at its inferior and posterior edge, sloped anteriorly, and
subauriculated, the left not being so; hinge toothless, anterior or
buccal; ligament inserted in an oblique cavity prolonged outwardly to
the summits, and carried within into a spoon-like cavity. Inhabits the
Indian Ocean. One species.

 Pedum spondyloideum.


                        2. Genus _Lima_. Pl. IX.

_Animal._ Body moderately compressed; a byssiferous abdominal appendage;
edges of the mantle furnished with tentacular cirri in several rows;
mouth surrounded with a very thick fringed lip.

_Shell._ Oval, more or less oblique, nearly equivalve, subauriculated,
regularly gaping at the anterior portion of the inferior edge; summits
anterior and distant; hinge buccal, longitudinal, toothless; ligament
rounded, nearly exterior, inserted in an excavation in each valve; a
central muscular impression, divided into three very distinct parts.
Inhabits the Indian, Australasian, American, and Mediterranean seas. Six
living species. Eleven fossil.

 Lima inflata.
 L. squamosa.
 L. annulata.
 L. glacialis.
 L. fragilis.
 L. linguatula.


                       3. Genus _Pecten_. Pl. IX.

_Animal._ Body more or less compressed, orbicular; mantle furnished with
a single row of tentacular papillæ, and with small oculiform,
pedunculated disks, with regular spaces between them; rudiment of a
canaliculated foot, and a byssus; mouth surrounded with fleshy
appendages, irregularly ramified.

_Shell._ Free, regular, thin, solid, equivalve, equilateral,
auriculated; summits contiguous; hinge toothless, a ligamentous membrane
throughout all its extent, besides a short, thick, ligament, almost
altogether internal, and filling a triangular excavation under the
summit; a single subcentral muscular impression. Found in almost all
seas. Sixty-two species; and, according to Defrance, ninety-eight
fossil.

 Pecten maximus.
 P. Jacobæus.
 P. bifrons.
 P. zigzag.
 P. medius.
 P. Latirentii.
 P. pleuronectes.
 P. purpuratus.
 P. pallius.
 P. impricatus.
 P. asperimus.
 P. varius.
 P. glaber.
 P. grisens.
 P. flabellatus.
 P. quadradiatus.
 P. Tranquebaricus.
 P. hybridus.
 P. obliteratus.
 P. Magellanicus.
 P. lineolaris.
 P. nodosus.
 P. pusio.
 P. gibbus.
 P. ornatus.
 P. florens.
 P. opercularis.
 P. tigris.
 P. histrionicus.
 P. turgidus.
 P. aspersus.
 P. plicus.
 P. rastellus.
 P. flagellatus.
 P. flavidulus.
 P. Japanicus.
 P. radulus.
 P. pes-felis.
 P. sauciatus.
 P. aurantius.
 P. sinuosus.
 P. virgo.
 P. Isabella.
 P. flexuosa.
 P. inflexus.
 P. miniaceous.
 P. lividus.
 P. sulcatus.
 P. unicolor.
 P. distans.
 P. irradians.
 P. dispar.
 P. Islandicus.
 P. sulphureus.
 P. pellucidus.
 P. sanguineous.
 P. senatorius.
 P. lunatus.
 P. lineatus.

        ·       ·       ·       ·       ·

 P. dislocatus.*
 P. concentricus.*
 P. monotimeris.*
 P. Latiauratus*
 P. Pealii.*


                    4. Genus _Plagiostoma_. Pl. IX.

_Animal._ Entirely unknown.

_Shell._ Moderately thick, regular, free, subequivalve, subauriculated,
the two valves nearly equally dilated, both provided with a distinct
summit reflexed to the middle of a plane surface, with a large
triangular slope in the middle; articulation transverse, straight, and
by two distant lateral condylæ. Ten species. Fossils only.


                     5. Genus _Plicatula_. Pl. IX.

_Animal._ Unknown.

_Shell._ Solid, adhering, subirregular, inauriculated, inequivalve,
pointed at the summit, rounded and subplicated posteriorly; inferior
valve without heel; hinge cephalic, longitudinal, provided upon each
valve with two strong teeth, entering in corresponding cavities;
ligament altogether internal and inserted in a median cavity. Inhabits
the American seas. Five species.

 Plicatula ramosa.
 P. depressa.
 P. cristata.
 P. Australis.
 P. reniformis.


                     6. Genus _Spondylus_. Pl. IX.

_Animal._ Body moderately compressed, provided inferiorly with a
rudiment of a foot, without byssus; mantle open in all its inferior and
superior portion; mouth surrounded with very thick and fringed lips.

_Shell._ Solid, adhering, subregular, more or less spined,
subauriculated, inequivalve; the right or inferior valve fixed, much
more excavated than the other, and having posteriorly at the summit a
triangular face enlarging, and elongating with age; hinge longitudinal,
provided in each valve with two strong teeth entering corresponding
cavities; ligament short, nearly median, partly exterior; muscular
impression single and subdorsal. Found in all the seas of hot climates,
and even in the Mediterranean. Four or five fossils are found in France,
one in South America. Twenty-one species.

 Spondylus candidus.
 S. coccineus.
 S. spathuliferus.
 S. gædaropus.
 S. arachnoides.
 S. multilamellatus.
 S. longitudinalis.
 S. costatus.
 S. longispinous.
 S. regius.
 S. variegatus.
 S. avicularis.
 S. zonalis.
 S. crassisquama.
 S. ducalis.
 S. violascens.
 S. microlepos.
 S. crocens.
 S. radians.
 S. aurantius.

        ·       ·       ·       ·       ·

 S. Americanus.*


                      7. Genus _Podopsis_. Pl. IX.

_Animal._ Unknown.

_Shell._ Subregular, somewhat thick, equilateral, symmetrical,
inequivalve, adhering by the extremity of the shorter valve; the other
terminating in a pointed, reflexed, and median summit. Two fossil
species.


                              FAMILY XIX.

                         OSTRACEA. Six genera.


                       1. Genus _Ostrea_. Pl. IX.

_Animal._ Body compressed, more or less orbicular; edges of the mantle
thick, not adhering or retractile, and provided with a double row of
short and numerous tentacular filaments; two pairs of elongated and
triangular labial appendages; a subcentral bipartite muscle.

_Shell._ Irregular, inequivalve, inequilateral, roughly foliaceous, the
left or inferior valve adhering, larger and deeper than the other, its
summit prolonged with age into a sort of heel; the right or superior
valve more or less operculiform; hinge oral, toothless; ligament
subinterior, short, inserted in an oblong cardinal cavity increasing
with the summit; muscular impression single and subcentral. Found in all
seas near the mouths of rivers. Defrance enumerates one hundred and
twenty species. Lamarck thirty-three fossil, forty-nine living.

 Ostrea edulis.
 O. ruscuriana.
 O. borealis.
 O. cochlear.
 O. gallina.
 O. lingua.
 O. Braziliana.
 O. rostralis.
 O. denticulata.
 O. cornucopiæ.
 O. doridella.
 O. Limacella.
 O. hippopus.
 O. Adriatica.
 O. cristata.
 O. numisma.
 O. tulipa.
 O. scabra.
 O. parasitica.
 O. spathulata.
 O. cucullata.
 O. rubella.
 O. erucella.
 O. labrella.
 O. radiata.
 O. Canadensis.
 O. mytiloides.
 O. trapezina.
 O. rufa.
 O. gibbosa.
 O. eliptica.
 O. deformis.
 O. plicatula.
 O. fusca.
 O. cristagalli.
 O. virginica.
 O. excavata.
 O. simuata.
 O. tuberculata.
 O. Magaritacea.
 O. Australis.
 O. haliotidæa.
 O. fucorum.
 O. glaucina.
 O. turbinata.
 O. folia.
 O. hyotis.
 O. imbricata.

        ·       ·       ·       ·       ·

 O. semicylindrica.*


                      2. Genus _Gryphæa_. Pl. IX.

_Animal._ Unknown.

_Shell._ More finely lamellated than in the _Ostrea_, free, or slightly
adhering, subequilateral, very inequivalve; the inferior valve very
concave, with a summit more or less recurved in a hook; the superior
opiculiform and much smaller; hinge toothless; ligament inserted in an
elongated and arcuated cavity; a single muscular impression. Habitation
unknown. One species.

 Gryphæa augulata.


                      3. Genus _Vulsella_. Pl. IX.

_Animal._ Body elongated and compressed; mantle much prolonged
posteriorly, and edged with two rows of very close tubercular papillæ; a
moderately large abdominal foot, proboscidiform, canaliculated, without
byssus; a very large transversal mouth with well-developed triangular
labial appendages; branchiæ narrow, very long, and united in nearly all
their extent.

_Shell._ Subnacred, irregular, flat, elongated, subequivalve,
inequilateral, with summits anterior, distant and flexed inferiorly;
hinge oral and toothless; ligament undivided, thick, inserted in a round
pit excavated in a projecting apophysis upon each valve; a moderately
large subcentral muscular impression, and two very small ones altogether
anterior. Inhabits the Indian and Australasian seas. Six living species.
One fossil.

 Vulsella hians.
 V. rugosa.
 V. spongiarum.
 V. lingulata.
 V. mytilina.
 V. ævata.


                      4. Genus _Placuna_. Pl. IX.

_Animal._ Entirely unknown.

_Shell._ Free, subirregular, very fine, almost entirely translucid,
flat, subequivalve, subequilateral, slightly auriculated; hinge
altogether internal, formed upon the superior valve, which is the
smaller, by two elongated, unequal, oblique, crests; converging to the
summit, at the internal side of which a ligament is attached in the form
of a V, a single, small, subcentral muscular impression. Inhabits the
Indian seas. Two fossils in France. Three living species.

 Placuna sella.
 P. papyracea.
 P. placenta.


                       5. Genus _Anomia_. Pl. IX.

_Animal._ Much compressed; edges of the mantle very fine; not adhering,
and furnished exteriorly with a row of tentacular filaments; contractile
muscle thick, divided into three parts, the largest of which passes
partially across a slope of the inferior valve, and often contains a
calcareous substance or small bone, adhering to marine bodies.

_Shell._ Adhering, irregular, inequivalve, inequilateral, ostraceous;
inferior valve a little flatter than the superior, divided at the summit
into two sloping branches, whose approximation forms a large oval hole;
the superior valve, which is the larger, has an oval excavation under
the summit; a subcentral muscular impression, divided into three parts.
Inhabits the British coasts. Two beautiful species are found on the
shores of Rhode Island and New Jersey. Nine species.

 Anomia patellaris.
 A. pyriformis.
 A. lens.
 A. cepa.
 A. electrica.
 A. membranacea.
 A. squamula.

        ·       ·       ·       ·       ·

 A. ephippium.*
 A. fornicata.*


                       6. Genus _Crania_. Pl. IX.

_Animal._ See Anomia.

_Shell._ Orbicular, the upper valve gibbous and conical; lower valve,
flat, with three perforations. Inhabits the Indian Ocean. One species.

 Crania orbicula.


                               FAMILY XX.

                       BRACHIOPODA. Three genera.


                      1. Genus _Orbicula_. Pl. IX.

_Animal._ Body much compressed and rounded; mantle open throughout its
whole circumference; two ciliated tentacular appendages.

_Shell._ Orbicular, much compressed, inequilateral, very inequivalve;
inferior valve very thin, adhering, imperforated, the superior
patelloid, with the summit more or less inclined towards the posterior
side. Inhabits the Norwegian seas. One living species. Two fossil.

 Orbicula Norwegica.


                    2. Genus _Terebratula_. Pl. IX.

_Animal._ Depressed, circular or oval, more or less elongated, with two,
long, pectinated, labial tentacula.

_Shell._ Thin, inequivalve, regular, subtrigonal; one of the valves
larger and more dilated than the other, which is sometimes operculiform;
hinge condyloid, in a straight line, and formed by two oblique articular
surfaces in one valve placed between corresponding projections in the
other. Inhabits the sea at the Zetland Islands. Two species are found in
America. Thirteen living species. Thirty-eight fossil.

 Terebratula dilatata.
 T. flavescens.
 T. dorsata.
 T. Vitrea.
 T. dentata.
 T. globosa.
 T. caput-serpentis.
 T. psittacea.
 T. rotunda.
 T. pisa.
 T. sanguinea.

        ·       ·       ·       ·       ·

 T. septentrionalis.*
 T. truncata.*


                      3. Genus _Lingula_. Pl. IX.

_Animal._ Depressed, oval, somewhat elongated, inclosed between two
lobes of a mantle, slit throughout its anterior half, and having
pectinated branchiæ adhering to the internal surface; mouth simple,
having on each side a long tentacular appendage ciliated in all its
external edge, and rolling itself up spirally in the shell.

_Shell._ With an epidermis, subequivalve, equilateral, depressed,
elongated, truncated anteriorly; the summit median and posterior; no
trace of ligament; a long fibro-gelatinous peduncle fixing the shell
vertically to submarine bodies; muscular impression multiple. Inhabits
the Indian Ocean. One species.

 Lingula anatina.




                               CLASS IV.
                               MOLLUSCA.


Animals soft, inarticulated, furnished with an anterior head, projecting
or salient; most frequently with eyes and tentaculæ, or possessing, at
their summit, arms disposed in the form of a coronet: their mouth either
short, elongated, or tubular, exsertile, and generally armed with hard
parts. Mantle diversified, having its edges free on the sides of the
body, or the lobes united, forming a sack, which in part envelopes the
animal; gills or respiratory organs various, circulation double, one
particular, the other general; heart unilocular, sometimes with the
auricles divided, and very distant; no medullary cord along the body,
but scattered nerves and ganglions. Twenty-two families.


                               FAMILY I.

                         PTEROPODA. Six genera.

Some genera of this family are without a testaceous covering, mentioned
only to preserve the family entire.


                       1. Genus _Hyalæa_. Pl. IX.

_Animal._ Body enclosed in a shell, winged before, two opposite wings,
somewhat retractile, inserted at the sides of the mouth, head distinct,
mouth terminal, placed at the junction of the fins; without eyes.

_Shell._ Symmetrical, very thin and transparent, valves unequal, flat
above, convex below, open like a cleft anteriorly, summit truncated and
tridentated posteriorly. Inhabits the Mediterranean. Two species.

 Hyalæa tridentata.
 H. cuspidata.


                        2. Genus _Clio_. Pl. IX.

_Animal._ Body free, naked, more or less elongated, tapering to the
rear, head very distinct; provided with six, long, conical, retractile
tentaculæ, separated into two groups of three each; mouth altogether
terminal and vertical, eyes sessile, rudiment of a foot under the neck.

This is a molluscous animal without any testaceous covering, but is here
placed as leading to other genera which have shells. Inhabits the Indian
seas. Two species.

 Clio borealis.
 C. Australis.


                      3. Genus _Cleodora_. Pl. IX.

_Animal._ Body oblong, gelatinous, contractile; a head in front with two
wings, and the posterior part enveloped in a shell, head distinct,
projecting and round; two eyes; mouth in the form of a small beak;
destitute of tentaculæ; two, opposite, membranaceous, pellucid, and
cordated wings, placed at the base of the neck.

_Shell._ Pyramidal, triangular, of a gelatinous or cartilaginous
substance, very thin and transparent; aperture obliquely truncated.
Inhabits the South American seas. Two species.

 Cleodora pyramidata.
 C. caudata.


                      4. Genus _Limacina_. Pl. IX.

_Animal._ Body soft, oblong, two branchial fins situated at the base of
the neck; posterior part of the body spiral, and enveloped in a shell.

_Shell._ Thin, fragile, papyraceous, spiral, the whorls reunited in a
planorbis form, and deeply and largely umbilicated on one side; aperture
large and entire. Inhabits the North seas. One species.

 Limacina helicialis.


                      5. Genus _Cymbulia_. Pl. IX.

_Animal._ Body oblong, gelatinous, pellucid, enclosing a shell; head
sessile; two eyes, and two retractile tentacula; mouth with a retractile
proboscis; two, opposite, oblong, ovate, branched wings, connate at
their posterior base.

_Shell._ Gelatinous, cartilaginous, very transparent, crystalline,
oblong, in shape of a shoe, from which it has derived the name of the
slipper, truncated at the summit; aperture lateral and anterior.
Inhabits the Mediterranean. One species.

 Cymbulia Peronii.


                    6. Genus _Pneumodermon_. Pl. IX.

A molluscous animal, without any testaceous covering, and much
resembling the genus Clio. Inhabits the Indian seas. One species.

 Pneumodermon Peronii.


                               FAMILY II.

                       PHYLLIDIACEA. Six genera.


                     1. Genus _Phyllidia_. Pl. IX.

A mollusca similar to the preceding genus, without a shell, but its back
covered with a rough or coriaceous skin. Inhabits the Mediterranean.
Three species.

 Phyllidia varicosa.
 P. pustulosa.
 P. ocellata.


                    2. Genus _Chitonellus_. Pl. IX.

_Animal._ Body creeping, elongated; middle of the back provided its
entire length with a detached, multivalve shell; the alternate pieces
for the most part longitudinal; sides naked; branchiæ disposed around
the body; foot cleft longitudinally by a deep furrow.

_Shell._ Each valve with striæ radiating from its apex; the margins
serrated; the base of the last valve obtuse. The testaceous plates of
this genus are never joined like those of the Chiton, so that the animal
can move in every direction. Upon the contraction of the animal after
death, however, these valves become nearly united. Inhabits the seas of
New Holland. Two species.

 Chitonellus striatus.
 C. larvæformis.


                       3. Genus _Chiton_. Pl. IX.

_Animal._ Body creeping, ovate oblong, convex, round at both
extremities; marginated with a coriaceous skin: the back covered by a
longitudinal series of testaceous, transverse, imbricated, and moveable
plates; head before, sessile, with the mouth placed below, destitute of
tentacula or eyes; branchiæ placed round the body, under the margin of
the skin; and orifice at the posterior extremity.

_Shell._ Eight imbricated valves, nearly smooth, slightly carinated, and
rounded at the margins: summit more or less marked and curved by
longitudinal elongations. Inhabits the British and American coasts.
Sixty-three species.

 Chiton fulvus.
 C. pisceus.
 C. ruber.
 C. lævis.
 C. spinosus.
 C. fascicularis.
 C. marginatus.
 C. crinitus.
 C. siculus.
 C. niger.
 C. spiniferous.
 C. coquimbensis.
 C. lumingii.
 C. granosus.
 C. glauco-sinctus.
 C. disjunctus.
 C. elegans.
 C. lineatus.
 C. sulcatus.
 C. bicolor.
 C. cerasimus.
 C. Magellanicus.
 C. marmoratus.
 C. nebulosus.
 C. olivaceous.
 C. latus.
 C. punctatus.
 C. viridus.
 C. cinerus.
 C. tunicatus.
 C. gigas.
 C. squamosus.
 C. Peruvianus.
 C. tesselatus.
 C. capensis.
 C. Carmichaelis.
 C. echinatus.
 C. striatus.
 C. lineolatus.
 C. chilensis.
 C. tuberculatus.
 C. hispidus.
 C. thalassimus.
 C. porosus.
 C. larvaformis.
 C. undulatus.
 C. luteolus.
 C. fuscus.
 C. minimus.
 C. cimex.
 C. ascellus.
 C. Icelandicus.
 C. fasciatus.
 C. setosus.
 C. variegatus.
 C. asselloides.
 C. indus.
 C. albas.
 C. castaneus.

        ·       ·       ·       ·       ·

 C. Emersonii.*
 C. fulminatus.*
 C. amœna.*
 C. alternata.*
 C. sagrinatus.*


                      4. Genus _Patella_. Pl. IX.

_Animal._ Body completely covered by the shell; head with two acute
tentaculæ, and the eyes situated at their exterior base; branchiæ placed
under the mantle and around the body.

_Shell._ This numerous and beautiful genus of Linnæus has been
subdivided into the several distinct genera of Fissurella, Emarginula,
Navicella, Umbrella, Pileopsis, Calyptrea, Crepidula, Parmophora, and
Ancylus; each of which possesses sufficiently well-defined characters to
authorize a separation, by which they may be more easily distinguished
from the still widely extended family of Patella. Oval, conic, or a
little depressed, outside green or brown, sometimes radiated with
various colours; having divergent striæ and concentric wrinkles, inside
glossy, iridescent, with yellow or fawn-coloured, purple, blue, or brown
radiations. Inhabits almost every coast. Forty-nine species.

 Patella safiana.
 P. testitudinaria.
 P. cochlear.
 P. compressa.
 P. granularis.
 P. decaurata.
 P. Magellanica.
 P. stellifera.
 P. vulgata.
 P. mammillaris.
 P. lineata.
 P. leucopleura.
 P. notata.
 P. Tarentina.
 P. punctata.
 P. puncturata.
 P. Javanica.
 P. tuberculifera.
 P. miniata.
 P. pellucida.
 P. tricostata.
 P. Australis.
 P. apicina.
 P. granatina.
 P. oculus.
 P. Galathia.
 P. pectinata.
 P. viridula.
 P. scutellar.
 P. radians.
 P. cærulea.
 P. plumbia.
 P. umbrella.
 P. pyramidata.
 P. luteola.
 P. aspera.
 P. spinifera.
 P. longicosta.
 P. barbata.
 P. angulosa.
 P. saccharina.
 P. laciniosa.
 P. plicata.

        ·       ·       ·       ·       ·
 P. amœna.*
 P. alternata.*
 P. alveus.*
 P. candida.*


                      5. Genus _Umbrella_. Pl. IX.

_Animal._ Body very thick and oval, provided with a dorsal shell; foot
large, smooth, and flat, surrounded by a border, anteriorly notched,
attenuated behind; head indistinct; four tentacula, the two upper ones
thick, short, and truncated, the other two thin, and shaped like
pedunculated crests; having foliaceous branchiæ.

_Shell._ External, orbicular, subirregular, nearly flat, slightly convex
above, white, with apex near the middle; margin acute, internal surface
rather concave; having a callous disk, coloured, depressed in the
centre, surrounded by a smooth border. Inhabits the Indian Ocean. Two
species.

 Umbrella Indica.
 U. Mediterranea.


                   6. Genus _Pleurobranchus_. Pl. IX.

_Animal._ Body creeping, fleshy; mantle and foot expanded; branchiæ
placed on the right side; cloak enveloping the shell; neck short,
contracted in some species, with an emarginate front, exhibiting the
commencement of the inferior tentacula, the upper ones tubular and
cloven; gills at the edge of the dorsal plait, mouth provided with a
short, retractile proboscis.

_Shell._ Depressed, oval, oblong, concentrically wrinkled, almost
entirely open, rounded and convoluted; the vertex with a single turn.
Inhabits the coast of Devonshire in England. Two species.

 Pleurobranchus Peronii.
 P. Laqueare.


                              FAMILY III.

                       CALYPTRACEA. Seven genera.


                    1. Genus _Parmophorus_. Pl. IX.

_Animal._ Body creeping, thick, oblong-ovate, broad behind, obtuse at
the extremities; border of the mantle cleft before, and suspended
vertically around; head distinct, and slit below; two conical contracted
tentacula, at the base of which are placed the eyes, which are somewhat
pedunculated; mouth below, funnel-shaped, oblique, truncated, and
concealed; branchial cavity opening anteriorly behind the head by a
transverse fissure.

_Shell._ Oblong, very depressed, slightly convex above, obtuse at
extremities, anteriorly channeled by a slight sinus, and having towards
the posterior part a small pointed apex, inclined backwards; the lower
surface slightly concave. Inhabits the Australian seas. Four species.
One fossil.

 Parmophorus Australis.
 P. brevicula.
 P. granulata.
 P. ambigua.


                     2. Genus _Emarginula_. Pl. IX.

_Animal._ Body creeping, with two, conical, tentacular eyes at the
external base; mantle large, partly covering the margin of the shell;
foot very large and thick.

_Shell._ Shield-like, conical; summit inclined; the cavity simple,
having a notch or hollow cut on its posterior margin; shells of this
genus are generally very small. Inhabits the British seas. Five species.

 Emarginula Blainvillii.
 E. Cuvierii.
 E. fissura.
 E. rubra.
 E. marginata.


                     3. Genus _Fissurella_. Pl. IX.

_Animal._ With the head truncated in front; two conical tentacula, with
eyes at their exterior base; mouth simple, terminal, and destitute of
jaws; two pectinated branchiæ projecting from the cavity; mantle large,
protruding beyond the shell.

_Shell._ Shield-shaped, conical recurved, summit entire, depressed,
concave below, perforated at the summit in the form of a key hole,
without a spire; the exterior surface ribbed longitudinally. Inhabits
the European and American seas. Twenty-two species.

 Fissurella Cayennensis.
 F. lilacina.
 F. Javanicensis.
 F. fascicularis.
 F. rosea.
 F. Barbadensis.
 F. radiata.
 F. nodosa.
 F. nimbosa.
 F. crassa.
 F. Græca.
 F. picta.
 F. pustula.
 F. hiantula.
 F. viridula.
 F. depressa.
 F. Peruviana.
 F. gibberula.
 F. minuta.
 F. plicata.

        ·       ·       ·       ·       ·

 F. alternata.*
 F. redimicula.*


                      4. Genus _Pileopsis_. Pl. X.

_Animal._ With two conical tentacula, and the eyes at their base;
branchiæ formed in a row under the anterior margin of the cavity, near
the neck.

_Shell._ Obliquely conical, anteriorly recurved, apex bent, almost
spiral; aperture rounded, elliptical, the anterior margin shortest,
acute, slightly sinuated; the posterior largest and rounded. One
elongated and arched muscular impression, situated under the posterior
margin. Inhabits the seas of Europe. Nine species.

 Pileopsis intorta.
 P. subrufa.
 P. spirirostris.
 P. retortella.
 P. ungarica.
 P. mitula.
 P. pennata.
 P. squamæformis.
 P. depressa.


                      5. Genus _Calyptrea_. Pl. X.

_Animal._ The same as preceding genus.

_Shell._ This genus derives its common name, “the Cup-and-Saucer
Limpit,” by having in the interior cavity a cup-shaped appendage, which
is sometimes vertical, and sometimes like a horse-shoe, with a muscular
impression of variable form, vertex ending in a small volution; smooth,
margin entire, very glossy within, and provided with a laminar plate.
Inhabits the Chinese and S. American seas. Nine species.

 Calyptrea porcellana.
 C. equestris.
 C. fornicata.
 C. peziza.
 C. angulata.
 C. tecum-sinense.
 C. scutellata.
 C. poculum.

        ·       ·       ·       ·       ·

 C. striata.*


                      6. Genus _Crepidula_. Pl. X.

_Animal._ Head anteriorly forked, having two conical tentacula, with the
eyes placed at their exterior base; mouth simple, destitute of jaws, and
situated in the bifurcation of the head; branchiæ with tufts and
projecting from the branchial cavity; the mantle never bordering the
shell; foot minute, orifice lateral.

_Shell._ Ovate, or oblong; the back almost always convex, concave
beneath; the spire very much inclined towards the margin; the aperture
partly closed by a horizontal lamina. Inhabits the American seas.
Thirteen species.

 Crepidula extinctorum.
 C. aculeata.
 C. lævigata.
 C. uguiformis.
 C. dilata.
 C. Peruviana.
 C. gigas.

        ·       ·       ·       ·       ·

 C. fornicata.*
 C. depressa.*
 C. glauca.*
 C. plana.*
 C. intorta.*
 C. convexa.*


                       7. Genus _Ancylus_. Pl. X.

_Animal._ Body creeping, enveloped in the shell; two compressed
subtruncated tentacular, with eyes situated at their internal base; foot
short, elliptical; somewhat narrower than the body.

_Shell._ Thin, obliquely conical; aperture oval, with a pointed apex,
which very much inclines backwards; margins simple. This is a fresh
water shell, found in the lakes of Europe and rivers of America. Five
species.

 Ancylus lacustris.
 A. fluviatilis.
 A. spinarosæ.

        ·       ·       ·       ·       ·

 A. rivularis.
 A. filosus.


                               FAMILY IV.

                        BULLACEA. Three genera.


                           1. Genus _Acera_.

_Animal._ Body ovate, convex, transversely divided above into two parts;
the foot with dilations in the form of wings below; head indistinct;
branchiæ situated on the back, greatly behind, and covered by a mantle
destitute of a shell. Inhabits the Mediterranean. One species.

 Acera carnosa.


                       2. Genus _Bullæa_. Pl. X.

_Animal._ Body ovate, somewhat convex above, and divided into two parts
transversely; lateral lobes of the foot very thick; head indistinct, and
without tentacula; branchiæ placed on the back.

_Shell._ Concealed in the mantle, very thin, rolled and spiral on one
side; without a columella and spire; aperture very large and wide,
dilated at the upper part. Inhabits the British seas. Two species.

 Bullæa aperta.
 B. striata.


                        3. Genus _Bulla_. Pl. X.

_Animal._ Body oblong-ovate, slight convexity; divided into two portions
transverse above, mantle slightly folded posteriorly; visible tentacula;
branchiæ dorsal and covered, opening only on the right side.

_Shell._ Univalve, ovate globular, convolute, no columella, spire not
projecting but visible, aperture the whole length of the shell, external
margin sharp and smooth. Inhabits the British and American seas.
Nineteen species.

 Bulla physis.
 B. naucum.
 B. hydatis.
 B. rugosa.
 B. fragilis.
 B. aplustre.
 B. ampulla.
 B. lignaria.
 B. fasciata.
 B. striata.
 B. Wyatii.
 B. solida.
 B. cornea.
 B. lactea.

        ·       ·       ·       ·       ·

 B. solitaria.*
 B. triticea.*
 B. hiemalis.*
 B. Gouldii.*
 B. lineolata.*


                               FAMILY V.

                        APLYSIACEA. Two genera.


                      1. Genus _Dolabella_. Pl. X.

_Animal._ Body creeping, oblong, narrowed in front; and posteriorly
widened; area round, sloping, and truncated obliquely; margins folded
over the back; four tubular tentacula, disposed in pairs; bronchial
operculum inclosing a shell; orifice dorsal, near the branchiæ.

_Shell._ Oblong, slightly arcuated, thick, callous, and somewhat spiral
on both sides, singular in formation, and its characteristic unlike most
other shells. Inhabits the Isle of France. Two species.

 Dolabella Rumphii.
 D. fragilis.


                       2. Genus _Aplysia_. Pl. X.

_Animal._ Body creeping, oblong, convex above; bordered on each side by
a broad mantle, which covers the back when the animal is in repose; head
and neck elevated, with four tentacula, the two upper ones ear-shaped,
eyes situated near the mouth; dorsal shield semicircular,
subcartilaginous, adhering on one side, and covering the branchial
cavity.

_Shell._ Nearly round, left margin somewhat reflected; outer lip acute;
yellowish horn colored, with brown radiations, and two concentric bands.
Inhabits the Indian seas. Thirty-seven species.

 Aplysia depilans.
 A. teremida.
 A. gigas.
 A. hassetlii.
 A. punctata.
 A. marmorata.
 A. dolabrifera.
 A. ascifera.
 A. petalifera.
 A. unguifera.
 A. Limacina.
 A. Jeachii.
 A. saviguana.
 A. fasciata.
 A. bresili.
 A. dactycomela.
 A. protea.
 A. sorex.
 A. tigrina.
 A. maculauta.
 A. longicauda.
 A. Kerandrenii.
 A. lessonii.
 A. camelus.
 A. alba.
 A. Napolitana.
 A. viridis.
 A. longicornis.
 A. ecaudata.
 A. virescens.
 A. poliana.
 A. fusca.
 A. pleii.
 A. citrini.
 A. undata.
 A. rosea.
 A. Ferrusacii.


                               FAMILY VI.

                         LIMACINA. Five genera.


                        1. Genus _Limax_. Pl. X.

_Animal._ Cuvier merely mentions that the animal is “furnished with a
coriaceous, subrogose shield, with a flat, longitudinal disk beneath;
four tentacula retractile, eyes at the tips; orifice for respiration on
the right side.”

_Shell._ Ovate oblong, both margins reflected; very thin, diaphanous,
slightly wrinkled, of a pale yellow colour. Inhabits the gardens in
Britain and France. Five species.

 Limax rufus.
 L. cinerus.
 L. albus.
 L. agrestis.
 L. punctata.


                       2. Genus _Vitrina_. Pl. X.

_Animal._ Body creeping, elongated, snail shaped, nearly straight;
posteriorly separated from the foot, and spirally wound into a shell.

_Shell._ Small, very thin, depressed, terminated above by a very short
spire, the last whorl very large; aperture large, rounded oval; the left
margin arched, slightly involute. Inhabits dry places of Europe. Three
species.

 Vitrina parilis.
 V. dentilis.
 V. pellucida.


                     3. Genus _Testacella_. Pl. X.

_Animal._ Body creeping, elongated, snail shaped, having a shell placed
on the posterior extremity; four tentacula, the two longest with their
eyes at their tips; respiratory organs behind.

_Shell._ Very small, external, ear-shaped, apex absolutely spiral,
aperture very large and oval, left edge sharp and rolled inward behind.
Inhabits the middle provinces of France. Two species.

 Testacella Haliotidea.
 T. Neritoidea.


                     4. Genus _Parmacella_. Pl. X.

_Animal._ Body creeping oblong; middle of the back moderately convex,
and shield-shaped; hind part in form of a tail, laterally compressed,
acute above; shield ovate, fleshy, adhering at its posterior part, free
before, enveloping a shell, with a notch in the centre of its right
margin; four tentacula, two posterior largest; respiratory organs, under
the notch of the shield, placed between the two tentacula of the right
side.

_Shell._ Ovate, left margin broad and reflected; right margin reflected
at top and acute beneath; very thin and pellucid, of a pale
yellowish-brown. Inhabits the gardens of Europe. Two species.

 Parmacella Olivieri.
 P. Cuvierii.


                      5. Genus _Onchidium_. Pl. X.

_Animal._ Body oblong, creeping, marginated on all sides; head
projecting, the lower part with a prominent margin, two retractile,
cylindrical tentacula; two auriform appendages, nearly lateral; mouth
beneath, destitute of maxillary processes; respiratory orifices
distinct, under the extremity of the body.

Destitute of a shell. Inhabits the gardens of Europe. Two species.

 Onchidium Typhæ.
 O. Peronii.


                              FAMILY VII.

                       COLIMACEA. Eleven genera.


                        1. Genus _Helix_. Pl. X.

_Animal._ Of a slightly variable form, the mantle forming at its free
edge a kind of ring or thick collar, especially in front, and faintly
divided into two lips; foot oval, plane, smooth beneath, inflated and
granular below, joined to the visceral club by a narrow peduncle; head
sufficiently distinct; anterior tentacula very evident and inflated at
top, the posterior very long; the mouth a vertical cleft provided with
two labial lobes, a sort of marginal tooth, with a small, oval, lingual
club.

_Shell._ The name Helix was given to this genus from the spiral shape of
the shell, which varies much in form, but generally globular, and
ventricose, conoid but never turriculated; summit generally obtuse,
aperture varying much in size, sometimes very large, sometimes small,
always regulated by the turn of the spire; oval, semilunar, more wide
than long, edges disunited, entering little into the interior; right lip
or margin thickened or reflected inwards. Inhabits the groves and woods
both of America and Europe. Two hundred and three species.

 Helix vesicalis.
 H. gigantea.
 H. polyzonalis.
 H. monozonalis.
 H. pulla.
 H. lineolata.
 H. mutata.
 H. pomatia.
 H. aspersa.
 H. vermiculata.
 H. Alonensis.
 H. vesicolor.
 H. naticoides.
 H. picta.
 H. galactites.
 H. cepa.
 H. heteroclites.
 H. discolor.
 H. lactea.
 H. zonaria.
 H. guttata.
 H. Madagascarensis.
 H. Javanica.
 H. Peruviana.
 H. simplex.
 H. cidaris.
 H. citrina.
 H. algira.
 H. verticellus.
 H. olivetorum.
 H. hæmastoma.
 H. melanotragus.
 H. extensa.
 H. lucana.
 H. globulus.
 H. melanostoma.
 H. cœlatura.
 H. microstoma.
 H. maculsa.
 H. Richardi.
 H. Bonplandii.
 H. planulata.
 H. labrella.
 H. unguina.
 H. pellis-serpentis.
 H. senegalensis.
 H. unidentata.
 H. fructicum.
 H. neglecta.
 H. crespitum.
 H. ericetorum.
 H. intersecta.
 H. Carthusianella.
 H. diaphana.
 H. concolor.
 H. velutina.
 H. obvuluta.
 H. Cookiana.
 H. pileus.
 H. papilla.
 H. punctifera.
 H. plicatula.
 H. planorbella.
 H. scabra.
 H. cariosa.
 H. crenulata.
 H. planorbula.
 H. macularia.
 H. planospira.
 H. Barbadensis.
 H. sinuata.
 H. hippocastanum.
 H. bidentalis.
 H. argilacea.
 H. vittata.
 H. arbustorum.
 H. candidissima.
 H. memoralis.
 H. Hortensis.
 H. sylvatica.
 H. pisana.
 H. splendida.
 H. serpentina.
 H. niciensis.
 H. variabilis.
 H. auriculata.
 H. turgidula.
 H. helicella.
 H. zonula.
 H. tridentata.
 H. septemvalva.
 H. monodan.
 H. fraterna.
 H. coniformis.
 H. concamerata.
 H. nigrescens.
 H. Tripolitana.
 H. Sayii.
 H. globulosa.
 H. Caffra.
 H. conformis.
 H. prunum.
 H. Pouzolzii.
 H. contusa.
 H. bicarinata.
 H. vitrinoides.
 H. maritima.
 H. strigata.
 H. muralis.
 H. rugosa.
 H. cornea.
 H. liquifera.
 H. incarnata.
 H. cinctella.
 H. cellaria.
 H. Gaymardii.
 H. nitidia.
 H. plebuim.
 H. personata.
 H. hispidia.
 H. rotundata.
 H. apicina.
 H. striata.
 H. conspurcata.
 H. conica.
 H. conoidea.
 H. pulchella.
 H. formosa.
 H. orbiculata.
 H. squamosa.
 H. tectiformis.
 H. Madeirensis.
 H. unbeculata.
 H. deformis.
 H. Nicæensis.
 H. meridionalis.
 H. melitensis.
 H. circumornata.
 H. gronosa.
 H. Lima.
 H. dentiens.
 H. parilis.
 H. imperator.
 H. zodiaca.
 H. concisa.
 H. pellicuta.
 H. strobilus.
 H. alanda.
 H. carina.
 H. Bulverii.
 H. pileolus.
 H. vipartita.
 H. sinistrorsa.
 H. fibula.
 H. supplicata.
 H. Porto-santara.
 H. punctulata.
 H. exalbida.

        ·       ·       ·       ·       ·

 H. Mitchelliana.*
 H. Vancouverensis.*
 H. Caroliniensis.*
 H. Nuttaliana.*
 H. Columbiana.*
 H. hirsuta.*
 H. perspectiva.*
 H. lineata.*
 H. multilineata.*
 H. appressa.*
 H. palliata.*
 H. Californiensis.*
 H. Townsendiana.*
 H. Nichliniana.*
 H. Oregonensis.*
 H. magnifica.*
 H. profunda.*
 H. albolabris.*
 H. alternata.*
 H. irrorata.*
 H. inorata.*
 H. indentata.*
 H. inflecta.*
 H. clausa.*
 H. obstricta.*
 H. elevata.*
 H. interna.*
 H. chersina.*
 H. gularis.*
 H. ligera.*
 H. solitaria.*
 H. jejuna.*
 H. concava.*
 H. fallax.*
 H. egena.*
 H. arboreus.*
 H. glaphyra.*
 H. Thyroides.*
 H. labyrinthica.*
 H. major.*
 H. Pennsylvanica.*
 H. subglobosa.*
 H. Zaleta*
 H. dentifera.*
 H. delabata.*


                      2. Genus _Carocolla_. Pl. X.

The _Animal_ of this and the following genera of this family are
precisely the same as in Helix.

_Shell._ Orbicular, more or less convex or conoidal above; the
circumference or periphery angulated or keeled; aperture transverse,
contiguous to the axis of the shell; the right margin or lip subangular,
often toothed or plaited beneath. Inhabits dry situations in Europe and
America. Twenty-two species.

 Carocolla acutistima.
 C. albilabris.
 C. angistoma.
 C. labyrinthus.
 C. lucerna.
 C. inflata.
 C. hispidula.
 C. Gaulteriana.
 C. albella.
 C. bicolor.
 C. Mauritiana.
 C. Madagascarensis.
 C. marginata.
 C. lychnuchus.
 C. planata.
 C. planaria.
 C. lapicida.
 C. elegans.

        ·       ·       ·       ·       ·

 C. Hydiana.*
 C. helicoides* (new species) _Lea_.
 C. grata.*
 C. Spinosa* (new species) _Lea_.


                      3. Genus _Achatina_. Pl. X.

_Animal._ See Helix.

_Shell._ Variable in form, but generally subturriculated, oval or
oblong, aperture entire, the right lip sharp, never reflected, columella
smooth, of which the anterior extremity is always open and truncated.
Inhabits South America. Twenty-four species.

 Achatina perdix.
 A. immaculata.
 A. acuta.
 A. Mauritania.
 A. ustulata.
 A. virginea.
 A. Marminii.
 A. fusco-lineata.
 A. columnaria.
 A. acicula.
 A. zebra.
 A. purpurea.
 A. bicarinata.
 A. castanea.
 A. vexillum.
 A. Priamus.
 A. Peruviana.
 A. albo-lineata.
 A. fulminea.
 A. folliculus.
 A. oleacea.

        ·       ·       ·       ·       ·

 A. glans.*
 A. Vanuxemensis.*
 A. solida.*


                      4. Genus _Anostoma_. Pl. X.

_Animal._ See Helix.

_Shell._ Somewhat extraordinary in its formation, orbicular, the spire
convex and obtuse, aperture round, dentated grinning, turned upwards to
the side of the spire, margin of the lip reflected. Lakes in America and
the Sandwich Islands. Three species.

 Anostoma dentata.
 Anostoma depressa.

        ·       ·       ·       ·       ·

 A. globosa.*


                      5. Genus _Helicina_. Pl. X.

_Animal._ See Helix.

_Shell._ Terrestrial, distinguished only from the Helix by its columella
being transverse callous; much depressed and diminished in thickness at
the lower part, subliglobular, imperforate; aperture entire, demioval,
margin acute, forming an angle at the lower base of the right lip;
operculum corneous. Inhabits groves in Europe. Nineteen species.

 Helicina neritella.
 H. rhodostoma.
 H. striata.
 H. fasciata.
 H. virida.
 H. pulchella.
 H. substriata.
 H. Braziliensis.
 H. costata.
 H. aurantia.
 H. major.
 H. minima.
 H. submarginata.
 H. unifasciata.
 H. Brownii.
 H. depressa.
 H. aureola.
 H. orbiculata.
 H. Tankervillii.


                        6. Genus _Pupa_. Pl. X.

_Animal._ See Helix.

_Shell._ Cylindrical, generally thick; aperture irregular, semi-ovate,
rounded, and subangulated beneath; margins of outer lip nearly equal and
reflected outwardly, unconnected at their upper parts; the plait of the
columella interposed between them. Most frequently found in moss in
Europe and America. Forty species.

 Pupa numia.
 P. uva.
 P. sulcata.
 P. candida.
 P. labrossa.
 P. fusus.
 P. tridentata.
 P. fasciolata.
 P. zebra.
 P. unicarinata.
 P. maculosa.
 P. clavulata.
 P. ovularis.
 P. Germanica.
 P. cinerea.
 P. tridens.
 P. quadridens.
 P. polyodon.
 P. variabilis.
 P. frumentum.
 P. secale.
 P. avena.
 P. granum.
 P. fragilis.
 P. dolium.
 P. umbilicata.
 P. muscorum.
 P. angilicus.
 P. rufescens.
 P. edontulis.
 P. odontostoma.
 P. petiveriana.
 P. dentata.

        ·       ·       ·       ·       ·

 P. contracta.*
 P. rupicola.*
 P. exigua.*
 P. armifera.*
 P. fallax.*
 P. ovata*
 P. pentadon.*


                      7. Genus _Clausilia_. Pl. X.

_Animal._ See Helix.

_Shell._ Cylindrical, generally fusiform; summit obtuse, the last whorl
smaller than the preceding; aperture irregular, rounded, oval; margin
united, and externally reflected. Inhabits dry situations both in Europe
and America. Fifteen species.

 Clausilia torticollis.
 C. truncatula.
 C. retusa.
 C. costulata.
 C. corrugata.
 C. inflata.
 C. Mediterranea.
 C. denticulata.
 C. collaris.
 C. papillaris.
 C. plicatula.
 C. rugosa.
 C. gracilis.
 C. chrysalis.

        ·       ·       ·       ·       ·

 C. teres.*


                       8. Genus _Bulimus_. Pl. X.

_Animals_ of this genus in formation are precisely as the Helix; they
are, however, oviparous, producing eggs with the shell containing the
animal perfectly matured; they are frequently as large as a pigeon’s
egg.

_Shell._ Oval, sometimes turriculated, oblong; the summit of the spire
obtuse, and the last whorl larger than all the others together; aperture
oblong, oval, edge disunited; in adults the lip much reflected;
columella smooth, with an inflection in the middle, the base entire, not
channeled. Inhabits mountainous situations in Europe and America; some
beautiful specimens have been found in the woods of Ohio. Sixty-three
species.

 Bulimus ovatus.
 B. hæmastomus.
 B. gallina.
 B. sultana.
 B. zigzag.
 B. multifasciatus.
 B. Bengalensis.
 B. Caribæorum.
 B. octonus.
 B. terebraster.
 B. undatus.
 B. Richii.
 B. inversus.
 B. citrinus.
 B. sultanus.
 B. Pythogaster.
 B. ovoideus.
 B. interruptus.
 B. Peruvianus.
 B. Favannii.
 B. Kambeul.
 B. papyraceus.
 B. calcareus.
 B. decollatus.
 B. Lyonetianus.
 B. inflatus.
 B. radiatus.
 B. fragilis.
 B. Guadalupensis.
 B. Mexicanus.
 B. articulatus.
 B. acutus.
 B. scobinatus.
 B. planidens.
 B. ventricosus.
 B. montanus.
 B. hordaceus.
 B. lubricus.
 B. iostoma.
 B. geniostoma.
 B. odontostoma.
 B. formosus.
 B. Listeri.
 B. Kingii.
 B. Dufresnii.
 B. pulcher.
 B. maugeri.
 B. lævis.
 B. auris leporis.
 B. vexillum.

        ·       ·       ·       ·       ·

 B. glandiformis.*
 B. parvus.*
 B. virgo.*
 B. gracilis.*
 B. Gibbonius.*
 B. multilatus.*
 B. maculatus.*
 B. Pealianus.*
 B. lacteus.*
 B. decoratus.*
 B. Columbianus.*
 B. multilineatus.*
 B. corneus.*


                      9. Genus _Succinea_. Pl. X.

_Animal._ See Helix.

_Shell._ Terrestrial, very thin, pellucid, ovate oblong, with a conical,
pointed spire, formed of only one or two whorls; aperture very large and
oval, edges disunited; right edge always acute, the left arched, formed
by a smooth attenuated columella. The shells of this genus never having
their lip thickened or reflected, distinguish them from those of the
genus Bulimus, to which they bear a strong resemblance. Inhabits the
sides of ditches and lakes, both in Europe and America. Seven species.

 Succinea cuculata.
 S. amphibia.
 S. rubescens.
 S. oblonga.
 S. patula.
 S. pellucida.

        ·       ·       ·       ·       ·

 S. aperta.*


                      10. Genus _Auricula_. Pl. X.

_Animal._ See Helix.

_Shell._ Solid, thick, and smooth, oval, oblong spire very obtuse,
aperture entire, enlarged, ear-shaped, much contracted behind; edges not
united, right lip thick and generally reflected outwardly; the left or
columella with one or more teeth or callous plaits. This genus derives
its name from its resemblance to the ears of certain animals. It is a
land shell found chiefly in the East and West India Islands. Sixteen
species.

 Auricula Midæ.
 A. Judæ.
 A. sileni.
 A. leporis.
 A. felis.
 A. Dombeiana.
 A. nitens.
 A. angiostoma.
 A. scarabæus.
 A. bovina.
 A. caprella.
 A. myosotis.
 A. minima.
 A. coniformis.
 A. monill.
 A. labrella.


                     11. Genus _Cyclostoma_. Pl. X.

_Animal._ See Helix.

_Shell._ Terrestrial, distinguished from the preceding genera by a
perfectly round aperture, reflected lip, and horny operculum, summit
papillose; left edge having its origin very detached from the spire.
Inhabits the East Indies. A few species are found in America.
Thirty-eight species.

 Cyclostoma planorbula.
 C. volvulus.
 C. carinata.
 C. sulcata.
 C. unicarinata.
 C. rugosa.
 C. labeo.
 C. interrupta.
 C. ambigua.
 C. semilabris.
 C. tricarinata.
 C. obsoleta.
 C. patulum.
 C. truncatum,
 C. pulchrum.
 C. Jamaicense.
 C. lineolata.
 C. elongatum.
 C. mirabile.
 C. orbella.
 C. aurantium.
 C. flavula.
 C. fasciata.
 C. mumia.
 C. quarternata.
 C. ferruginea.
 C. decussata.
 C. mammillaris.
 C. maculatum.
 C. ligata.
 C. elegans.
 C. tortum.
 C. mirabile.

        ·       ·       ·       ·       ·

 C. maculata.*
 C. Popayana.*
 C. lapidaria.*
 C. marginata.*
 C. dentata.*


                              FAMILY VIII.

                        LYMNACEA. Three genera.


                       1. Genus _Lymnea_. Pl. X.

_Animal._ See Helix.

_Shell._ Aquatic, oval, sometimes turreted; spire produced, thin,
smooth, edges disunited, the left with a very oblique plait rising on
the columella, forming an oval aperture, destitute of an operculum.
Inhabits the ponds of America and Europe. Thirty-three species.

 Lymnea columnaris.
 L. stagnelis.
 L. palustris.
 L. auricularia.
 L. ovata.
 L. minuta.
 L. luteola.
 L. acuminata.
 L. intermedia.
 L. leucostoma.
 L. peregra.

        ·       ·       ·       ·       ·

 L. rubiginosus.*
 L. solida.*
 L. Virginiana.*
 L. Emmoniensis.*
 L. lessoni.*
 L. apacina.*
 L. catascopium.*
 L. columella.*
 L. elongatus.*
 L. reflexus.*
 L. appressus.*
 L. elodes.*
 L. limosa.*
 L. lapidaria.*
 L. dissimilis.*
 L. ponderosa.*
 L. integra.*
 L. porata.*
 L. lustrica.*
 L. grana.*
 L. subglobosa.*


                        2. Genus _Physa_. Pl. X.

_Animal._ See Helix.

_Shell._ General sinistral, oval, oblong, or globular, very smooth,
spire prominent, aperture oval, contracted posteriorly, right edge
sharp, columella twisting obliquely, and enlarging to join itself to the
anterior part of the margin, the whorls turning to the left hand gives
this shell the appellation of heterostrophe. Inhabits the ditches of
America and Europe. Ten species.

 Physa fontinalis.
 P. hypnorum.
 P. subopaca.

        ·       ·       ·       ·       ·

 P. castanea.*
 P. decisa.*
 P. elongata.*
 P. aurea.*
 P. gyrina.*
 P. heterostropha.*
 P. ancillaria.*


                      3. Genus _Planorbis_. Pl. X.

_Animal._ See Helix.

_Shell._ Discoid, spire depressed, or involuted almost in the same
vertical plane, causing the shell to be depressed on each side, aperture
oblong, luniform, axis remote, margin not reflected; no operculum.
Inhabits the lakes of America and Europe. Twenty-two species.

 Planorbis cornu-arietis.
 P. corneus.
 P. spirorbis.
 P. hispidus.
 P. orientalis.
 P. carinatus.
 P. lutescens.
 P. nitidus.
 P. angulatus.
 P. deformis.
 P. imbricatus.
 P. contortus.
 P. vortex.

        ·       ·       ·       ·       ·

 P. lens.*
 P. glabratus.*
 P. armigerus.*
 P. parallellus.*
 P. exacuous.*
 P. campanulatus.*
 P. trivolvis.*
 P. bicarinatus.*
 P. parvus.*


                               FAMILY IX.

                        MELANIANA. Three genera.


                       1. Genus _Melania_. Pl. X.

_Animal._ See Helix.

_Shell._ Turreted; aperture entire, spire slightly pointed, margin of
the whorls often surmounted by spires, columella smooth and arched,
closed by a thin horn-like operculum; this is a fluviatile shell, often
covered by a thick epidermis. Inhabits the rivers of India. Many fine
species are found in America. Fifty-four species.

 Melania inquinata.
 M. asperata.
 M. spinolusa.
 M. gronifera.
 M. aurita.
 M. lineolata.
 M. trunculata.
 M. carinefera.
 M. truncata.
 M. coarctata.
 M. punctata.
 M. subulata.
 M. Helvetica.
 M. lineata.
 M. Byronensis.
 M. sulcata.
 M. lævigata.
 M. clavis.
 M. decollata.
 M. amarula.
 M. thiarella.
 M. fasciolata.
 M. lævissima.
 M. corrugata.

        ·       ·       ·       ·       ·

 M. Troostiana.*
 M. plicifera.*
 M. Sayii.*
 M. elevata.*
 M. armigera.*
 M. multilineata.*
 M. proxima.*
 M. Hydeii.*
 M. salebrosa.*
 M. bitaeniata.*
 M. lema.*
 M. nassula.*
 M. trochiformis.*
 M. elevata.*
 M. laqueata.*
 M. semicarinata.*
 M. subularis* (_Lea_).
 M. acuta.* „
 M. plicata.*
 M. inflata.*
 N. conica.*
 M. catenaria.*
 M. simplex.*
 M. excurta.*
 M. annulifera.*
 M. pyrenella.*
 M. coma.*
 M. alveare.*
 M. cylindracea.*
 M. vestita.*
 M. caniculata.*
 M. Virginica.*
 M. tuberculata* (_Lea_).
 M. elongata.* „


                       2. Genus _Pirena_. Pl. X.

_Animal._ Much elongated, mantle prolonged into a canal at the left
side, but without distinct tube; foot short, oval, with an anterior
marginal furrow; head terminated by a depressed proboscidiform muzzle;
tentacula very distant, thickly annulated, dilated in the inferior half
of their length, and having the eyes at the summit of this dilation;
mouth a terminal and vertical slit, without labial tooth, and with a
very small tongue; a single long and narrow branchia.

_Shell._ Distinguished from the preceding genus by having a sinus at the
base, and another at the summit; turreted; aperture longitudinal, right
lip sharp, base of the columella inclined to the right. Inhabits the
rivers of India and Africa. One species is found in America. Six
species.

 Pirena terebralis.
 P. cancellata.
 P. aurita.
 P. spinosa.
 P. granulosa.

        ·       ·       ·       ·       ·

 P. scalariformis.*


                     3. Genus _Melanopsis_. Pl. X.

_Animal._ As preceding genus.

_Shell._ The Melanopsis is distinguished from the Melanaia, by the
columella being callous in the upper part, and the base truncated as in
the Achatina, and differs from the Pirena in having only a sinus or
widened opening at the base of the shell; aperture covered by a horny
operculum. Inhabits the rivers of the Archipelago. Three species.

 Melanopsis costata.
 M. lævigata.
 M. prærosa.


                               FAMILY X.

                      PERISTOMIANA. Three genera.


                       1. Genus _Valvata_. Pl. X.

_Animal._ See Helix.

_Shell._ Found only in fresh water; subdiscoid or conoid, umbilicated,
spiral, whorls, rounded; angular at the summit; aperture round, not
modified by the penultimate whorl; the margins sharp and united;
operculum orbicular and horny. Inhabits the rivers of Europe and
America. Three species.

 Valvata piscinalis.

        ·       ·       ·       ·       ·

 V. arcnifera.* (_Lea_.)
 V. tricarinata.*


                      2. Genus _Paludina_. Pl. X.

_Animal._ See Helix.

_Shell._ Generally found in fresh water, though some species have been
found where it is salt; conoid covered with a greenish epidermis; the
whorls rounded or convex, spiral cavity modified by the last whorl;
aperture rounded, oval, oblong, angular at the summit; margins united,
acute, never reflected outwards; operculum orbicular and horny. Inhabits
the rivers of America and Europe. Thirty-one species.

 Paludina vivipara.
 P. Bengalensis.
 P. viridis.
 P. Francesii.
 P. achatina.
 P. Australis.
 P. impura.
 P. muriatica.

        ·       ·       ·       ·       ·
 P. sinistrosa.*
 P. Nuttaliana.*
 P. virens.*
 P. pallida.*
 P. subcarinata.*
 P. genicula.*
 P. magnifica.*
 P. limosa.*
 P. subglobosa.*
 P. lapidaria.*
 P. Virginica.*
 P. hyalina.*
 P. unicolor.*
 P. nuclea.*
 P. decisa.*
 P. fuscus.*
 P. dissimilis.*
 P. ponderosa.*
 P. integra.*
 P. porata.*
 P. lustrica.*
 P. grana.*
 P. Nickliniana.*


                     3. Genus _Ampullaria_. Pl. X.

_Animal._ Inflated, globular, spiral; foot oval, with a transverse
furrow at its anterior edge; head wide; tentacula superior, very long,
conical, and pointed; eyes situated at their external base, and
supported upon a very apparent peduncle; mouth vertical, situated
between two lips disposed in form of a horse-shoe and forming a kind of
muzzle; no superior tooth; a bristly lingual band, but not prolonged
into the abdominal cavity; a very large respiratory cavity, divided in
two by an incomplete horizontal partition.

Animals of this genus are oviparous; producing an egg nearly as large as
that of a pigeon, in which is found the young animal complete, and in a
perfectly formed shell.

_Shell._ This genus appears to partake of the characteristics, both of
the Paludina and the Natica, being fluviatile and frequently attaining a
large size; spire very short, the last whorl much larger than all the
others together; globular, very ventricose, umbilicus small, forming a
compressed funnel-shaped aperture, without interior callosity; aperture
longer than broad, with margins united; columellar lip thickened,
projecting and reflected over the umbilicus; operculum horny. Inhabits
the rivers of Europe. Thirteen species.

 Ampullaria vivipara.
 A. fasciata.
 A. rugosa.
 A. canaliculata.
 A. effusa.
 A. virens.
 A. avellana.
 A. fragilis.
 A. Guinica.
 A. carinata.
 A. intorta.
 A. conica.

        ·       ·       ·       ·       ·

 A. Pealiana.*


                               FAMILY XI.

                        NERITACEA. Four genera.


                      1. Genus _Neritina_. Pl. X.

_Animal._ Globular; foot circular, thick, without a furrow anteriorly,
or a lobe for the operculum posteriorly, with a bipartite columellar
muscle; conical tentacula; eyes subpedunculate at their external side;
mouth without labial tooth, but with a denticulated tongue prolonged
into the visceral cavity; a single large pectiniform branchia.

_Shell._ This genus was formerly classed with the Nerita, which in form
it much resembles, but from the circumstance of the latter inhabiting
the sea, and Neritinæ fresh water, it now forms a separate genus. Thin,
smooth, or finely striated, in all the species known, the right side of
the aperture does not possess any crenulations or teeth; the operculum
is provided with a lateral tooth on one side. Some species are armed
with spines; aperture semicircular; left margin smooth and sharp; spire
imperfect, generally dissolved by the animal. Inhabits the fresh water
rivers of Europe. Twenty-seven species.

 Neritina perversa.
 N. pulligera.
 N. dubia.
 N. zebra.
 N. zigzag.
 N. gagates.
 N. lugubris.
 N. lineolata.
 N. fasciata.
 N. semiconica.
 N. strigilata.
 N. meleagris.
 N. virginea.
 N. fluviatilis.
 N. viridis.
 N. Bætica.
 N. careosa.
 N. caffra.
 N. Domingensis.
 N. auriculata.
 N. crepidularia.
 N. brevispina.
 N. Smithii.
 N. spinosa.
 N. Oweni.
 N. pulchella.
 N. corona.


                       2. Genus _Nerita_. Pl. X.

_Animal._ See Neritina.

_Shell._ Marine, but never spined, solid, semiglobular, flattened
beneath, not imbilicated; aperture large, entire, semilunar, the
external margin much hollowed; the columella sharp and often dentated,
operculum horny, subspiral, with a projecting tooth. Inhabits the seas
of S. America and W. Indies. Twenty species.

 Nurita exuvia.
 N. textilis.
 N. undata.
 N. peloronta.
 N. chlorostoma.
 N. atrata.
 N. polita.
 N. albicella.
 N. chamæleon.
 N. versicolor.
 N. lineata.
 N. scabricosta.
 N. plicata.
 N. tassellata.
 N. signata.
 N. ornata.
 N. Australis.
 N. rudis.
 N. Ascensionis.
 N. Malaccensis.


                      3. Genus _Navicella_. Pl. X.

_Animal._ Oval, not spiral, foot elliptical, very large, with a thin
subpapillary edge, advanced rather anteriorly, without marginal furrow,
but attached on each side to the visceral mass in all its posterior
portion so as to form a sort of cavity open transversely behind; head
very broad and semilunate; tentacula conical, contractile and distant;
eyes subpedunculated at the external root of the tentacula; mouth large
and longitudinal.

_Shell._ Fluviatile, elliptical, or oblong, convex above, summit
straight, depressed to the margin, concave beneath; no columella; the
columellar edge replaced by a sharp partition, covering part of the
aperture; a sinus at its left extremity; muscular impression horse-shoe
shaped, open in front and interrupted behind; thin, calcareous
operculum, with a subulate, lateral tooth adhering to the posterior
margin. Inhabits rivers in the Isle of France. Four species.

 Navicella elliptica.
 N. tesselatus.
 N. lineata.
 N. porcelanica.


                      4. Genera _Natica_. Pl. XI.

_Animal._ Oval, subspiral; foot profoundly and transversely bilobed
anteriorly, and having a horny or calcareous operculum; head provided
with long setaceous tentacula, flat, and auriculated at the base; eyes
sessile at the external side of the root of the tentacula; mouth armed
with a labial tooth.

_Shell._ Marine, distinguished from the Nerita by having no teeth, and
having an umbilicus modified by a callosity; very smooth and glossy; no
epidermis; spire evident, but low; columellar edge not toothed; right
edge without teeth; operculum calcareous and smooth, semi-spiral, with
concentrical ribs, fitting a groove on the columella. Inhabits the W.
Indian Ocean and American seas. Thirty-six species.

 Natica ampullaria.
 N. plumbea.
 N. conica.
 N. aurantia.
 N. melanostoma.
 N. mamilla.
 N. mamillaris.
 N. albumen.
 N. glaucina.
 N. canrena.
 N. cruentata.
 N. millepunctata.
 N. vitellus.
 N. helvacca.
 N. collaria.
 N. monilifera.
 N. labrella.
 N. unifasciata.
 N. lineata.
 N. fulminata.
 N. maculosa.
 N. vitata.
 N. castanea.
 N. arachnoidea.
 N. zebra.
 N. Marochiensis.
 N. Javanica.
 N. zonaria.
 N. cancellata.
 N. patula.
 N. duplicata.
 N. intricata.
 N. glabrata.
 N. Chinensis.
 N. rufa.

        ·       ·       ·       ·       ·
 N. consolidata.*
 N. duplicata.*
 N. heros.*
 N. pusilla.*
 N. triseriata.*
 N. rugosa.*


                              FAMILY XII.

                         JANTHINEA. One genus.


                      1. Genus _Janthina_. Pl. XI.

_Animal._ Of oval form, spiral, provided with a circular concave foot,
accompanied with a vesicular subcartilaginous mass, and natatory
appendages on each side; head very thick; tentacula scarcely at all
contractile; eyes situated beneath the extremity of long peduncles
placed at the external side of the tentacula, and appearing to form a
part of them; mouth at the extremity of a very thick proboscidiform
muzzle, between two vertical, subcartilaginous lips furnished with sharp
spines.

_Shell._ Of a beautiful violet colour, found in numbers floating on the
surface of the ocean, suspended by a vesicular appendage which gives a
rich purple stain. Extremely thin and fragile, spire low, lateral,
pointed, with subcarinated whorls; aperture large, subangular, modified
by the last whorl of the spire, edges disunited, the left formed by the
columella, which is straight, continuing beyond the base, right edge
sharp, with a sinus in the middle. Inhabits the Atlantic Ocean. Three
species.

 Janthina naticoides.
 J. communis.
 J. exigua.


                              FAMILY XIII.

                      MACROSTOMIANA. Four genera.


                     1. Genus _Sigaretus_. Pl. XI.

_Animal._ Body oval, flat beneath; edges of the mantle vertical, thin,
extending beyond the body in all directions, sloped anteriorly; the
mantle itself dilated superiorly.

_Shell._ More or less thick, internal, without colour, much depressed,
with a short, low, lateral spire; left edge of the aperture trenchant;
two lateral muscular impressions very distant. Inhabits the Indian
Ocean. Two species are found in S. America. Six species.

 Sigaretus convexus.
 S. Haliotoideus.
 S. cancellatus.
 S. lævigatus.

        ·       ·       ·       ·       ·

 S. perspectivus.*
 S. maculatus.*


                     2. Genus _Stomatella_. Pl. XI.

_Animal._ Unknown.

_Shell._ Distinguished from the Stomatia by being destitute of a
transverse rib, orbicular, oblong ear-shaped, imperforate; aperture
entire, large, sublongitudinal; right lip effuse, dilated, open.
Inhabits the Indian Ocean. Five species.

 Stomatella imbricata.
 S. rubra.
 S. sulcifera.
 S. auricula.
 S. planulata.


                      3. Genus _Stomatia_. Pl. XI.

_Animal._ Unknown.

_Shell._ Ear-shaped, imperforate, spire prominent; aperture entire,
large, oblong; right margin and columella equally raised; a transverse
and tuberculated rib on the back. Inhabits the Indian Ocean. Two
species.

 Stomatia phymotis.
 S. obscurata.


                      4. Genus _Haliotis_. Pl. XI.

_Animal._ Body oval, much depressed, slightly spiral posteriorly,
provided with a large foot doubly fringed at its circumference; head
depressed; tentacula a little flattened; eyes at the summit of prismatic
peduncles situated at the external side of the tentacula; mantle very
thin, deeply slit at the left side; the two lobes pointed, and forming
by their union a kind of canal to conduct water into the branchial
cavity, and including two very long unequal branchial combs.

_Shell._ This beautiful genus derives its name from its resemblance to
the human ear. The exterior, tuberculated, and generally loaded with
marine substances, giving it an uncouth appearance, but its iridescent
interior forms a magnificent contrast; it is pearly, with all the hues
of the rainbow, recurving very depressed, oval, spire very small,
sometimes eroded, almost posterior, aperture as large as the shell, with
margins reflected inwards, the right sharp, left flat, and enlarged;
disk pierced with holes, disposed in a line parallel to and near the
left margin, the last commencing with a notch. These holes formed by the
animal, as it increases the size of the shell, to admit the passage of a
short syphon; they adhere to rocks, and are removed with much
difficulty. Inhabits the sea at Molucca. Nineteen species.

 Haliotis tuberculata.
 H. striata.
 H. asinina.
 H. glabia.
 H. lamellosa.
 H. unilateralis.
 H. rugosa.
 H. canaliculata.
 H. tricostalis.
 H. dubia.
 H. iris.
 H. tubifera.
 H. excavata.
 H. Australis.
 H. Midæ.
 H. rubra.
 H. tricostata.
 H. corrugata.
 H. Mariæ.


                              FAMILY XIV.

                         PLICACEA. Two genera.


                     1. Genus _Tornatella_. Pl. XI.

_Animal._ Body oval, subspiral; foot divided into two heels by a wide
transverse furrow; head provided with two vertical cylindrical
tentacula, having the eyes placed sessilely upon their interior side.

_Shell._ Convolute, oval, cylindrical, mostly striated transversely; no
epidermis; spire very short, last whorl much larger than all the others
together; one or two large plaits on the columella. Inhabits the coast
of Britain. Six species.

 Tornatella fasciata.
 T. solidula.
 T. auricula.
 T. nitidula.
 T. pedipes.
 T. flammea.


                    2. Genus _Pyramidella_. Pl. XI.

_Animal._ As preceding genus.

_Shell._ Smooth and turreted, without epidermis; elongated, conical, or
subturriculated; aperture entire, demioval; the outer lip sharp and
dentated within, columella produced, subperforate at the base, furnished
with transverse plaits. Inhabits the American and W. Indian seas. Six
species.

 Pyramidella terrebellum.

        ·       ·       ·       ·       ·

 Pyramidella maculosa.*
 P. dolabrata.*
 Pyramidella plicata.*
 P. ventricosa.*
 P. corrugata.*


                               FAMILY XV.

                        SCALARINA. Three genera.


                      1. Genus _Scalaria_. Pl. XI.

_Animal._ Spiral; foot short, oval, and inserted beneath the neck; two
tentacula terminated by a filament, and having the eyes at the extremity
of the dilated portion; a proboscis.

_Shell._ Marine, aperture circular, spire more or less pressed and
furnished with longitudinal ribs, formed by the preservation of the
reflected margin of the aperture; edges united, thickened, and outwardly
reflected; operculum horny and thin. Inhabits the American and Indian
seas. Fourteen living species, and three fossil.

 Scalaria coronata.
 S. communis.
 S. Australis.
 S. tenebralis.
 S. varicosa.
 S. raricosta.
 S. lamellosa.
 S. pretiosa.

        ·       ·       ·       ·       ·

 S. Martinii.*
 S. Novanglia.*
 S. lineata.*
 S. subulata.*
 S. multistriata.*
 S. turbinata.*


                      2. Genus _Vermetus_. Pl. XI.

_Animal._ As preceding genus.

_Shell._ Very similar to the Serpula, but the organization of the animal
makes it a distinct genus; often found clustered together, and attached
to marine substances; conical, thin, tubular, loosely spiral, aperture
straight, circular, edges sharp and complete, several partitions not
perforated towards the summit, operculum horny and complete. Inhabits
the sandy shores of the W. Indies and Africa. Two species.

 Vermetus lumbricalis.
 V. maximus.


                     3. Genus _Delphinula_. Pl. XI.

_Animal._ See Scalaria.

_Shell._ Thick, and pearly in the interior, subdiscoid or conical;
spiral whorls rough or angular, often detached, spiny; large umbilicus,
sometimes triangular; the margins united, mostly fringed or ventricose.
Inhabits the Indian and American seas. Five living species. Seven
fossil.

 Delphinula laciniata.
 D. turbinopsis.
 D. distorta.
 D. rugosa.

        ·       ·       ·       ·       ·

 D. laxa.*


                              FAMILY XVI.

                       TURBINACEA. Eight genera.


                      1. Genus _Solarium_. Pl. XI.

_Animal._ Unknown.

_Shell._ Orbicular, depressed, umbilicus large and conical, crenulated
or dentated on the inner margin of the whorls; aperture not modified by
the last whorl of the spire, which is entirely flat; no columella.
Inhabits the Indian seas. Seven living species. E. fossil.

 Solarium granulatum.
 S. perspectivum.
 S. hybridum.
 S. lævigatum.
 S. stramineum.
 S. variegatum.
 S. luteum.


                      2. Genus _Trochus_. Pl. XI.

_Animal._ Spiral, having the sides of the body often ornamented with
digitated or lobed appendages, and provided with a short foot, rounded
at its two extremities; head provided with two tentacula more or less
elongated, having the eyes upon a dilation of their external base; mouth
without superior tooth, but furnished with a spiral lingual band.

_Shell._ Marine, found in almost all parts of the world, some smooth,
others knotted, spined, tuberculated, or undulated; thick, generally
pearly, spire sometimes depressed, at others elevated and pointed at the
summit, sharp or carinated at its circumference, frequently umbilicated,
not always; aperture transversely depressed, the margins not united at
the upper part; columella arched and twisted, often projecting forward;
operculum horny, thin, with numerous spiral whorls, increasing from the
centre to the circumference. Inhabits the European seas. Ninety-nine
living species. Eight fossil.

 Trochus imperialis.
 T. longispina.
 T. solaris.
 T. Indicus.
 T. radians.
 T. pileus.
 T. calyptræformis.
 T. fimbriatus.
 T. brevispina.
 T. rotularius.
 T. stella.
 T. stellarius.
 T. asperatus.
 T. rhodostomus.
 T. spinulosus.
 T. jujubinus.
 T. Javanicus.
 T. annulatus.
 T. doliarius.
 T. granulatus.
 T. granatum.
 T. moniliferus.
 T. iris.
 T. ornatus.
 T. bicingulatus.
 T. calliferus.
 T. umbilicaris.
 T. undatus.
 T. Pharaonis.
 T. sagittiferus.
 T. costulatus.
 T. inermis.
 T. agglutinans.
 T. coelatus.
 T. tuber.
 T. magus.
 T. merula.
 T. argyrostomus.
 T. Cookii.
 T. niloticus.
 T. pyramidalis.
 T. noduliferus.
 T. cærulescens.
 T. obeliscus.
 T. virgatus.
 T. maculatus.
 T. granosus.
 T. squarrosus.
 T. incrassatus.
 T. flamulatus.
 T. elatus.
 T. marmoreus.
 T. Mauritianus.
 T. imbricatus.
 T. triseliatus.
 T. crenulatus.
 T. asperulus.
 T. acutus.
 T. concavus.
 T. lineatus.
 T. zizyphinus.
 T. conuloides.
 T. conulus.
 T. zonatus.
 T. carneolus.
 T. cinerarius.
 T. excavatus.
 T. nanus.
 T. pyramidatus.
 T. erythroleucos.
 T. undosus.
 T. unguis.
 T. olivaceus.
 T. Smithii.
 T. maugeri.
 T. Mediterraneus.
 T. reticulatus.
 T. indistinctus.
 T. pellioserpentis.
 T. armillatus.
 T. acuminatus.
 T. elegantus.
 T. granosus.
 T. tæniatus.
 T. articulatus.
 T. pictus.
 T. callosus.
 T. clanguloides.
 T. interruptus.
 T. lævis.
 T. albidus.
 T. celandii.
 T. quadricostatus.
 T. Byronianus.
 T. elongatus.
 T. filosus.
 T. clangulus.
 T. sulcatus.
 T. Montagui.


                     3. Genus _Monodonta_. Pl. XI.

_Animal._ See Trochus.

_Shell._ This genus appears to be the connecting link between the
Trochus and Turbo; distinguished from the former, by an entirely rounded
aperture, slightly depressed; from the latter, by the toothlike
projecting angle the truncated columella occasions at the base; an
operculum. Inhabits the Chinese seas. Thirty-four species.

 Monodonta bicolor.
 M. pagodus.
 M. tectum-persicum.
 M. papillosa.
 M. coronaria.
 M. Ægyptiacea.
 M. carchedonius.
 M. modulus.
 M. Listeri.
 M. tectum.
 M. labio.
 M. Australis.
 M. canalifera.
 M. viridis.
 M. fragarioides.
 M. constricta.
 M. tricarinata.
 M. badia.
 M. articulata.
 M. lugubris.
 M. punctulata.
 M. caniculata.
 M. seminigra.
 M. rosea.
 M. lineata.
 M. rugosa.
 M. zebra.
 M. reticularis.
 M. trochlea.
 M. atrata.
 M. obscura.
 M. concamerata.
 M. odontis.
 M. pulcherrima.


                       4. Genus _Turbo_. Pl. XI.

_Animal._ Very similar to that of Trochus, the sides sometimes
ornamented with tentacular appendages, varying in number and form; head
proboscidiform; tentacula thin and setaceous.

_Shell._ Depressed conical, or subturreted; sometimes umbilicated,
frequently carinated at its circumference; interior pearly; aperture
round or depressed, the middle of external edge hollowed; edges rarely
joined by a callosity; columella arched, rarely twisted, not truncated
at the base; an operculum. Inhabits the Indian and American seas.
Fifty-one species.

 Turbo marmoratus.
 T. imperialis,
 T. torquatus.
 T. muricatus.
 T. littoreus.
 T. ustulatus.
 T. Sarmaticus.
 T. cornutus.
 T. argyrostomus.
 T. chrysostomus.
 T. radiatus.
 T. setosus.
 T. Spenglerianus.
 T. petholatus.
 T. undulatus.
 T. pica.
 T. versicolor.
 T. smaragdus.
 T. cidaris.
 T. diaphanus.
 T. rugosus.
 T. coronatus.
 T. crenulatus.
 T. margaritaceus.
 T. vestitus.
 T. incarnatus.
 T. Nicobaricus.
 T. neritoides.
 T. retusus.
 T. bicarinatus.
 T. rudis.
 T. obtusus.
 T. pullus.
 T. cærulescens.
 T. cancellatus.
 T. costatus.
 T. niger.
 T. minimus.
 T. tuberculatus.
 T. zebra.
 T. pintado.
 T. crassus.
 T. fluctuatus.
 T. hippocastanum.
 T. cineræus.
 T. obscurus.
 T. saxosus.

        ·       ·       ·       ·       ·

 T. irroratus.*
 T. canaliculatus.*
 T. palliatus.*
 T. obligatus.*


                      5. Genus _Planaxis_. Pl. XI.

_Animal._ Unknown.

_Shell._ Ovate conical, solid; aperture ovate, sublongitudinal,
columella flat and truncated at the base, separated from the right
margin by a narrow sinus. Interior surface of the right margin furrowed
or lineated, and a callosity running under the summit. Inhabits the
American and W. Indian seas. Four species.

 Planaxis sulcata.
 P. bicolor.
 P. undulata.

        ·       ·       ·       ·       ·

 P. lævigatum.*


                    6. Genus _Phasianella_. Pl. XI.

_Animal._ Spiral; foot oval; upon each side an appendage ornamented with
filaments; head edged anteriorly with a kind of veil formed by a double,
bifid, fringed lip; two, long, conical tentacula; eyes borne upon short
peduncles and situated at the external part of their base; mouth between
two vertical subcornate lips.

_Shell._ Marine; many of them very rare and valuable; their beauty of
colouring disposed so as to resemble the plumage of a pheasant. Oval,
rather thick, smooth and glossy, spire pointed; columella uniting itself
with the left edge, forming interiorly a longitudinal callosity;
aperture oval, larger before, with edges disunited; operculum
calcareous, oval, oblong, subspiral, the summit at one extremity.
Inhabits the British coast. Twelve species.

 Phasianella variegata.
 P. rubens.
 P. bulimoides.
 P. elegans.
 P. lineata.
 P. nebulosa.
 P. sulcata.
 P. angulifera.
 P. lineolata.
 P. perdix.
 P. Mauritania.
 P. Peruviana.


                     7. Genus _Turritella_. Pl. XI.

_Animal._ Spiral; foot fringed anteriorly by a transversely wrinkled
band; tentacula long, very fine towards their extremity, somewhat thick
at their base, and having the eyes upon an inflation; the head skirted
with a veil or fringe garnished with filaments.

_Shell._ Turreted, not nacred, rather thin, striated in the direction of
the decurrence of the spire; very pointed, and with numerous whorls;
aperture rounded; the edges posteriorly, the right exceedingly thin, and
slightly sinuous towards the middle; operculum horny. Inhabits the
Indian and American Oceans. Twenty-one living species. Thirty-seven
fossil.

 Turritella duplicata.
 T. imbricata.
 T. terebra.
 T. replicata.
 T. fuscata.
 T. brevialis.
 T. trisulcata.
 T. carinifera.
 T. cornea.
 T. bicingulata.
 T. exoleta.
 T. Australis.

        ·       ·       ·       ·       ·

 T. Virginiana.*
 T. alternata.*
 T. impressa.*
 T. concava.*
 T. saturalis.*
 T. equalis.*
 T. erosa.*
 T. reticulata.*
 T. bisuturalis.*


                      8. Genus _Rotella_. Pl. XI.

_Animal._ See Turbo.

_Shell._ Orbicular, glossy, destitute of epidermis; spire short,
subconic; lower parts convex and callous; aperture half round. Indian
Ocean. Seven species.

 Rotella lineolata.
 R. Javanica.
 R. rosea.
 R. formosa.
 R. saturalis.
 R. equalis.
 R. monolifera.


                              FAMILY XVII.

                       CANALIFERA. Eleven genera.


                     1. Genus _Cerithium_. Pl. XI.

_Animal._ Much elongated; the mantle prolonged into a canal at its left
side, but without a distinct tube; the foot short, oval, with an
anterior marginal furrow; the head terminated by a depressed
proboscidiform muzzle.

_Shell._ More or less turriculated and tuberculous; aperture small,
oval, and oblique; the columellar edge much excavated and callous, the
right edge trenchant, and slightly dilating with age. Operculum horny,
oval, round, subspiral, and striated, upon the external face. They are
found in almost every sea. Forty-five living species. Sixty fossil.

 Cerithium palustre.
 C. telescopium.
 C. nodulosum.
 C. obeliscum.
 C. aluco.
 C. giganteum.
 C. sulcatum.
 C. ebeninum.
 C. vulgatum.
 C. granulatum.
 C. echinatum.
 C. subulatum.
 C. zonale.
 C. tortulosum.
 C. morus.
 C. erythræonense.
 C. radula.
 C. decollatum.
 C. semigranosum.
 C. lineatum.
 C. fasciatum.
 C. muricatum.
 C. crassum.
 C. obtusum.
 C. asperum.
 C. vertagum.
 C. literatum.
 C. heteroclites.
 C. semiferrugineum.
 C. tuberculatum.
 C. ocellatum.
 C. atratum.
 C. eburneum.
 C. lima.
 C. zonatum.
 C. rugosum.
 C. mitriforme.
 C. punctatum.
 C. perversum.
 C. petrosum.

        ·       ·       ·       ·       ·

 C. exasperatum.*
 C. dislocatum.*
 C. Emersonii.*
 C. Nigrocinctum.*
 C. Greenii.*


                     2. Genus _Pleurotoma_. Pl. XI.

_Animal._ Body oval, spiral above, enveloped in a mantle of which the
right edge is furnished with lobes; foot oval and somewhat short; eyes
situated at the external base of long, conical, retractile tentacula;
mouth having a long extensible proboscis armed with hooked teeth; organs
of respiration formed by two unequal branchiæ.

_Shell._ Fusiform, a little wrinkled, with a turriculated spire; a small
oval aperture, terminated by a straight canal more or less long, with
the right edge trenchant; a horny operculum. Distinguished from the
Cerithium by having a notch in the margin. Twenty-nine living species.
Thirty fossil.

 Pleurotoma muricata.
 P. echinata.
 P. flavidula.
 P. imperialis.
 P. auriculifera.
 P. spirata.
 P. bimarginata.
 P. cingulifera.
 P. Babylonia.
 P. marmorata.
 P. crispa.
 P. nodifera.
 P. maculata.
 P. interrupta.
 P. cincta.
 P. crenularis.
 P. unizonalis.
 P. lineata.
 P. fascialis.
 P. buccinoides.
 P. virgo.
 P. undosa.
 P. tigrina.
 P. albina.
 P. mitra.
 P. elegans.
 P. curvirostris.

        ·       ·       ·       ·       ·

 P. decussata.*
 P. bicarinata.*


                     3. Genus _Turbinella_. Pl. XI.

_Animal._ Imperfectly known.

_Shell._ Usually turbinated (but sometimes turriculated), wrinkled,
thick; spire slightly variable in form; aperture elongated, terminated
by a straight canal, and often rather short; the left edge nearly
straight and formed by a callosity concealing the columella, which has
two or three nearly transverse and unequal folds; the right edge entire
and trenchant. Found in the Equatorial or Australian seas. Twenty-three
species.

 Turbinella scolymus.
 T. napus.
 T. pugillaris.
 T. rapa.
 T. pyrum.
 T. leucozonalis.
 T. cingulifera.
 T. mitis.
 T. infundibulum.
 T. lineata.
 T. triserialis.
 T. ocellata.
 T. rustica.
 T. polygonia.
 T. carinifera.
 T. rhinoceros.
 T. cornigera.
 T. ceramica.
 T. capitella.
 T. globulus.
 T. craticulata.
 T. nassatula.
 T. variolaris.


                    4. Genus _Cancellaria_. Pl. XI.

_Animal._ See _Purpura_, hereafter.

_Shell._ Oval or globular, wrinkled; spire middling and pointed;
aperture wide, ovate, grooved, and sometimes canaliculated anteriorly;
the right edge concave and trenchant; the left nearly straight and
marked in the middle with two or three folds; operculum horny. Inhabits
the Indian Ocean. One species only is found in America. Forty-nine
living species. Twenty fossil.

 Cancellaria crispa.
 C. costifera.
 C. articularis.
 C. brevis.
 C. pusilla.
 C. bullata.
 C. tuberculosa.
 C. pulchra.
 C. cancellata.
 C. similis.
 C. chrysostoma.
 C. rugosa.
 C. hæmastoma.
 C. rigida.
 C. costata.
 C. goniostoma.
 C. trigonostoma.
 C. levigata.
 C. spirata.
 C. obliquata.
 C. scalata.
 C. contabulata.
 C. crenifera.
 C. scalarina.
 C. littoriniformis.
 C. elegans.
 C. asperella.
 C. oblonga.
 C. tesselata.
 C. nodulifera.
 C. cassidiformis.
 C. Australis.
 C. reticulata.
 C. candida.
 C. ovata.
 C. Obesa.
 C. acuminata.
 C. solida.
 C. gemmulata.
 C. decussata.
 C. indentata.
 C. alba.
 C. clavatula.
 C. uniplicata.
 C. mitriformis.
 C. tritonis.
 C. granosa.
 C. piscatoria.

        ·       ·       ·       ·       ·

 C. buccinoides.*


                    5. Genus _Fasciolaria_. Pl. XI.

_Animal._ Entirely unknown.

_Shell._ Separated from the Murex on account of having no varix fusiform
or subfusiform; spire middling; aperture oval, elongated, nearly
symmetrical, terminated by a rather long, straight tube, the external
edge trenchant, the columellar edge having two or three oblique folds.
Inhabits the Indian Ocean and Mediterranean Sea. Eight living species.
Seven fossil.

 Fasciolaria trapezium.
 F. aurantica.
 F. filamentosa.
 F. coronata.
 F. ferruginea.
 F. tarentina.
 F. tulipa.
 F. distans.


                       6. Genus _Fusus_. Pl. XI.

_Animal._ Entirely unknown.

_Shell._ With an epidermis, wrinkled, fusiform or dilated in the middle,
prolonged posteriorly by the spire, and still more so anteriorly by the
canal; aperture oval; the columellar edge straight or nearly so, the
exterior trenchant; a horny and oval operculum. Inhabits the Indian and
American seas. Forty-six living species. Thirty-seven fossil.

 Fusus aculeiformis.
 F. contrarius.
 F. longissimus.
 F. laticosta.
 F. collosseus.
 F. tuberculatus.
 F. distans.
 F. incrassatus.
 F. sulcatus.
 F. despectus.
 F. proboscidiferus.
 F. morio.
 F. cochlidium.
 F. raphanus.
 F. polygonoides.
 F. lignarius.
 F. strigosus.
 F. crebricostatus.
 F. colus.
 F. Nicobaricus.
 F. tortulosus.
 F. multicarinatus.
 F. antiquirus.
 F. carinatus.
 F. Islandicus.
 F. coronatus.
 F. corona.
 F. filosus.
 F. verruculatus.
 F. Syracusanus.
 F. varius.
 F. afer.
 F. rubens.
 F. Nifat.
 F. buccinatus.
 F. scalarinus.
 F. curvirostris.
 F. inconstans.
 F. sinistralis.
 F. articulatus.

        ·       ·       ·       ·       ·

 F. pleurotomarius.*
 F. harpularis.*
 F. cinereus.*
 F. fluviatilis.*
 F. decemcostatus.*
 F. bicolor.*


                       7. Genus _Pyrula_. Pl. XI.

_Animal._ Unknown.

_Shell._ Pyriform on account of the depression of the spire, which
distinguishes it from the Fusus; the canal conical, very long or
middling, sometimes a little sloped; aperture oval, rather large; the
columella edge somewhat excavated, entire and trenchant; an operculum.
Found in the Northern and American seas. Twenty-nine living species. Six
fossil.

 Pyrula salmo.
 P. carica.
 P. candelabrum.
 P. tuba.
 P. melongena.
 P. ficus.
 P. spirata.
 P. elongata.
 P. bezoar.
 P. angulata.
 P. nodosa.
 P. abbreviata.
 P. deformis.
 P. lineata.
 P. plicata.
 P. canaliculata.
 P. perversa.
 P. bucephala.
 P. vespertilio.
 P. reticulata.
 P. ficoides.
 P. spirillus.
 P. ternatana.
 P. rapa.
 P. galeodes.
 P. squamosa.
 P. citrina.
 P. neritoidea.

        ·       ·       ·       ·       ·

 P. papyracea.*


                   8. Genus _Struthiolaria_. Pl. XI.

_Animal._ See Triton, hereafter.

_Shell._ Ovate; spire prolonged; aperture sinuous, terminated at the
base by a very short, straight canal: columellar edge callous; right
edge having a thickened varix. Inhabits the Mediterranean and Northern
Seas. Two species.

 Struthiolaria nodulosa.
 S. crenulata.


                      9. Genus _Ranella_. Pl. XI.

_Animal._ Unknown.

_Shell._ Oval, and, as it were, depressed by the preservation of each
side of a longitudinal thickened band; aperture oval, almost symmetrical
by the excavation of the columellar edge, terminating anteriorly by a
short canal, often a little sloping; a sinus at the posterior junction
of the two edges. This genus forms a distinct division between the Murex
and Struthiolaria. Inhabits the Northern and Mediterranean Seas. One
species is found in America. Fifteen living species. Five fossil.

 Ranella gigantea.
 R. candisata.
 R. ranina.
 R. bufonia.
 R. granifera.
 R. bitubercularis.
 R. anceps.
 R. leucostoma.
 R. Argus.
 R. spinosa.
 R. granulata.
 R. semigranosa.
 R. crumena.
 R. pygmæa.

        ·       ·       ·       ·       ·

 R. caudata*.


                       10. Genus _Murex_. Pl. XI.

_Animal._ See _Pleurotoma_, above.

_Shell._ Usually oval; the spire but slightly elevated, roughened with
longitudinal, transversal bands or varices; aperture small, quite oval,
and symmetrical by the excavation of the left edge, formed by a lamina
applied upon the columella, terminated anteriorly by a middling canal
sometimes very long and closed; the right edge more or less furnished
with varices. Operculum horny, complete, oval, nearly circular, with
sub-concentric partitions; summit terminal. This genus comprehends only
such shells as have only three or more varices on each whorl. These
varices show how often the animal has increased the size of its shell.
F. in all seas. Seventy-three living species. Two fossil.

 Murex cornutus.
 M. tenuispina.
 M. ternispina.
 M. motacilla.
 M. palmarosæ.
 M. adustus.
 M. crevicornis.
 M. microphyllus.
 M. phylopterus.
 M. trigonularis.
 M. brandaris.
 M. rarispina.
 M. haustellum.
 M. inflatus.
 M. brevifrons.
 M. rufus.
 M. acaleatus.
 M. capucinus.
 M. acanthopterus.
 M. ucinarius.
 M. crassispina.
 M. brevispina.
 M. tenuirostrum.
 M. elongatus.
 M. calcitrassa.
 M. axicornis.
 M. longispina.
 M. asperrimus.
 M. tripterus.
 M. hemitripterus.
 M. gibbosus.
 M. brassica.
 M. radix.
 M. scorpico.
 M. turbinatus.
 M. melonulus.
 M. erinaceus.
 M. costularis.
 M. angularis.
 M. cingulatus.
 M. torosus.
 M. granarius.
 M. aciculatus.
 M. ferrugo.
 M. pinnatus.
 M. triqueter.
 M. saxatilis.
 M. melanomathos.
 M. secundus.
 M. trunculus.
 M. Magellanicus.
 M. tarentinus.
 M. polygonulus.
 M. crispatus.
 M. cinguliferus.
 M. lyratus.
 M. fimbriatus.
 M. regius.
 M. funiculus.
 M. pictus.
 M. trigonulus.
 M. endivia.
 M. hexagonus.
 M. quadrifrons.
 M. anguliferus.
 M. lamellosus.
 M. scaber.
 M. vitulinus.
 M. fenestratus.
 M. subcarinatus.
 M. concatenatus.
 M. pulchellus.
 M. cristata.
 M. lubiosus.


                      11. Genus _Triton_. Pl. XI.

_Animal._ As above.

_Shell._ Oval with straight spire and canal, middling generally
wrinkled, furnished with varices, rare, scattered, and preserved in
longitudinal rows; aperture suboval, elongated, terminated by a short
open canal; the columellar edge less excavated than the right and
covered by a callosity; operculum horny, oval, round, and rather large.
Found in the Northern and Mediterranean seas. Thirty-one living species.
Three fossil.

 Triton variegatum.
 T. lampas.
 T. corrugatum.
 T. lotorium.
 T. cynocephalum.
 T. retusum.
 T. vespaceum.
 T. clathratum.
 T. maculosum.
 T. cutaceum.
 T. undosum.
 T. nodiferum.
 T. scorbiculator.
 T. succinctum.
 T. femorale.
 T. tripus.
 T. clavator.
 T. chlorostomum.
 T. subdistortum.
 T. clandestinum.
 T. dolarium.
 T. australe.
 T. Splengleri.
 T. pileare.
 T. pigrum.
 T. canaliferum.
 T. tuberosum.
 T. anus.
 T. cancellatum.
 T. rubecula.
 T. tranquebaricum.


                             FAMILY XVIII.

                          ALATA. Three genera.


                    1. Genus _Rostellaria_. Pl. XI.

_Animal._ Entirely unknown.

_Shell._ Subdepressed, turriculated, with a produced and pointed spire;
aperture oval on account of a rather large excavation of the columellar
edge, the right margin dilating with age and having a sinus contiguous
to the pointed canal which terminates the shell; an operculum. This
genus is distinguished from the Strombus by having a sinus in the lower
part of the right margin contiguous to the canal. Inhabits the European
seas; four living species. Three fossil.

 Rostellaria curvirostris.
 R. rectirostris.
 R. pespelicani.
 R. cancellata.


                    2. Genus _Pteroceras_. Pl. XII.

_Animal._ See Strombus, below.

_Shell._ Oblong-ovate; canal elongated, attenuated and often closed;
right margin dilating by age into an expanded digitated wing, attached
to and covering a short spire with a sinus in the lower part not
contiguous to the body. Distinguished from the Strombus by not having
the canal at the base shortened or truncated, and from the Rostellaria
by having the sinus of the right margin distant from the body. Found in
the Equatorial seas. Seven species. Five fossil.

 Pteroceras truncata.
 P. lambio.
 P. scorpio.
 P. chiragra.
 P. millepeda.
 P. pseudoscorpia.
 P. aurantia.


                     3. Genus _Strombus_. Pl. XII.

_Animal._ Spiral; the foot rather wide anteriorly, compressed
posteriorly; mantle thin, forming a prolonged fold anteriorly, whence
issues a sort of canal; head very distinct; mouth a vertical slit at the
extremity of a proboscis, provided in the inferior median line with a
lingual band having prickles flexed posteriorly; tentacular appendages
cylindrical, thick, and long, with the eyes at their extremity.

_Shell._ Thick, subinvolute, dilated in the middle, terminating in a
cone anteriorly and posteriorly; aperture very long and narrow;
terminated anteriorly by a canal more or less elongated and flexed;
edges parallel, the external dilating with age, presenting posteriorly a
gutter at its point of attachment with the spire, and, anteriorly, a
sinus behind the canal, through which the head of the animal passes;
operculum horny, long, and narrow; summit terminal. Found in the Indian
and Equatorial seas, and one species in Florida. Thirty-two living
species. Five fossil.

 Strombus gigas.
 S. latissimus.
 S. Canarium.
 S. vittatus.
 S. gallus.
 S. cristatus.
 S. bubonius.
 S. auris-Dianæ.
 S. pyrulatus.
 S. Luhuanus.
 S. colomba.
 S. troglodytes.
 S. urceus.
 S. lineatus.
 S. turritus.
 S. accipitrimus.
 S. tricornis.
 S. Isabella.
 S. epidromis.
 S. bituberculatus.
 S. dilatus.
 S. lentiginosus.
 S. pugilis.
 S. gibberulus.
 S. Mauritianus.
 S. succinctus.
 S. tridentatus.
 S. plicatus.
 S. papilio.
 S. marginatus.
 S. cancellatus.

        ·       ·       ·       ·       ·

 S. Floridus.*


                              FAMILY XIX.

                      PURPURIFERA. Eleven genera.


                    1. Genus _Cassidaria_. Pl. XII.

_Animal._ Somewhat elongated, widened anteriorly; mantle with simple
edges and provided with a distinct tube; foot very wide, elliptical,
sub-biolate anteriorly, and having a large operculum upon the dorsal
face of its posterior part; head wide and indistinct; tentacula
anterior, approximating at base, subcylindrical, and having the eyes at
two-thirds of their length; mouth inferior, concealed by the foot; two
pectiniform branchiæ, nearly parallel.

_Shell._ Subglobular, tuberculated or channeled, with a short, pointed
spire; aperture long, ovate, subcanaliculated anteriorly; right edge
folded back; columella covered by a wide, smooth callosity, uniting
posteriorly with the right edge. Inhabits all seas except the Northern.
Five living species. Seven fossil.

 Cassidaria echinophora.
 C. Tyrrhena.
 C. striata.
 C. oniscus.
 C. cingulata.


                      2. Genus _Cassis_. Pl. XII.

_Animal._ Spiral, with the foot (which is shorter than the shell)
rounded anteriorly; mantle provided, before the respiratory cavity, with
a long open canal, used as an organ of prehension; head furnished; a
single pair of blackish tentacula, having the eyes at an inflation about
half way from the base; mouth armed with a proboscis.

_Shell._ Inflated, oval, subinvolute; spire slightly projecting;
aperture long, oval, sometimes very narrow, terminated anteriorly by a
very short canal, sloped, and flexed obliquely towards the back;
columella covered by a large callosity, indented throughout its length;
operculum horny. Found in the Indian, Mediterranean, and Equatorial
seas. Twenty-five living species. Eight fossil.

 Cassis cornuta.
 C. flammea.
 C. rufa.
 C. achatina.
 C. areola.
 C. abbreviata.
 C. saburon.
 C. Ceylonica.
 C. erinaceus.
 C. tuberosa.
 C. fascinata.
 C. pennata.
 C. crumena.
 C. zebra.
 C. sulcosa.
 C. canaliculata.
 C. semigranosa.
 C. Madagascariensis.
 C. glauca.
 C. testiculus.
 C. plicaria.
 C. decussata.
 C. granulosa.
 C. pyrum.
 C. vibex.


                     3. Genus _Ricinula_. Pl. XII.

_Animal._ As above.

_Shell._ Oval or subglobular, thick, armed with points and with a
depressed spire; aperture narrow, elongated, notched, sometimes
canaliculated anteriorly and digitated exteriorly; left edge more or
less callous; operculum horny, oval, and transverse. Found in the Indian
seas. Nine living species.

 Ricinula horrida.
 R. arachnoidea.
 R. digitata.
 R. aspera.
 R. clathrata.
 R. miticula.
 R. pisolina.
 R. morus.
 R. mutica.


                      4. Genus _Purpura_. Pl. XII.

_Animal._ As above.

_Shell._ Oval, tuberculated, thick; spire short, the last whorl much
larger than all the others united; aperture oval, greatly dilated,
terminated anteriorly by a short, oblique canal notched at the
extremity; the columellar edge nearly straight, covered with a
callosity; operculum horny, flat, nearly semicircular, with faintly
marked transverse striæ. Found in the European and South American seas.
Sixty-two species.

 Purpura Persica.
 P. columellaria.
 P. armigera.
 P. undata.
 P. bufo.
 P. planospira.
 P. carinifera.
 P. squamosa.
 P. sertum.
 P. ligata.
 P. imbricata.
 P. bicostalis.
 P. thiarella.
 P. echinulata.
 P. unifascialis.
 P. clavus.
 P. bizonalis.
 P. Francolinus.
 P. cruentata.
 P. lagenaria.
 P. plicata.
 P. rustica.
 P. hystrix.
 P. retusa.
 P. fasciolaris.
 P. nucleus.
 P. subrostrata.
 P. patula.
 P. consul.
 P. hippocastana.
 P. mancinella.
 P. neritoides.
 P. coronata.
 P. sacella.
 P. bulbus.
 P. cariosa.
 P. Rudolphi.
 P. succincta.
 P. bitubercularis.
 P. hæmastoma.
 P. callosa.
 P. callifera.
 P. scalariformis.
 P. rugosa.
 P. textilosa.
 P. lambosa.
 P. lapillus.
 P. cateracta.
 P. fiscella.
 P. semi-imbricata.
 P. deltoides.
 P. trochlea.
 P. vexillum.
 P. distorta.
 P. tectum.

        ·       ·       ·       ·       ·

 P. engonata.*
 P. brevidens.*
 P. lapilloidis.*
 P. harpa.*
 P. Floridana.*
 P. dumosa.*
 P. macrostoma.*


                     5. Genus _Monoceros_. Pl. XII.

_Animal._ As above.

_Shell._ Differs only from the _Purpura_ by a long, conical pointed,
somewhat reflexed tooth in the outer lip. Five species.

 Monoceros cingulatum.
 M. imbricatum.
 M. striatum.
 M. glabratum.
 M. crassilabrum.


                    6. Genus _Concholepas_. Pl. XII.

_Animal._ Entirely unknown.

_Shell._ Wide, rough, ovate; spire very short; aperture very large, oval
and sloped anteriorly; the edges united, the right very thick and
dentated; muscular impression almost in form of a horse-shoe; operculum
horny and rudimentary. It was formerly considered a Patella, from which
it differs by the operculum. One species.

 Concholepas Peruvianus.


                       7. Genus _Harpa_. Pl. XII.

_Animal._ Unknown.

_Shell._ Oval, inflated, rather thin, with longitudinal parallel ribs,
formed by the preservation of the band of the right margin; the spire
very short and pointed, the last whorl much longer than all the others
together; aperture large, ovate, with a wide slope anteriorly; the right
edge much hollowed, and thickened outwardly; the columella smooth and
terminated in a point anteriorly. A beautiful genus. Found in the Indian
Ocean. Nine species.

 Harpa imperialis.
 H. ventricosa.
 H. conoidalis.
 H. minor.
 H. nobilis.
 H. articularis.
 H. rosea.
 H. striata.
 H. mutica.


                      8. Genus _Dolium_. Pl. XII.

_Animal._ As in _Purpura_.

_Shell._ Subglobular, thin, surrounded by decurrent flutings; spire very
short, the last whorl much larger than all the others together; aperture
oblong, very large, on account of the great excavation of the right
edge, which is crenated throughout its length; columella twisted. Found
in the Indian Ocean and Mediterranean seas. Seven species.

 Dolium galea.
 D. fasciatum.
 D. pomum.
 D. variegatum.
 D. perdix.
 D. olearium.
 D. maculatum.


                     9. Genus _Buccinum_. Pl. XII.

_Animal._ See _Purpura_.

_Shell._ With a light epidermis, oval, elongated; the spire moderately
elevated; aperture oblong, oval, notched, sometimes subcanaliculated
anteriorly; right edge thick, not reflexed; columella simple and dilated
superiorly; operculum horny, complete, and oval. Found in all seas.
Sixty-six living. Fourteen fossil.

 Buccinum undatum.
 B. papyraceum.
 B. tenniplicatum.
 B. levigatum.
 B. crenulatum.
 B. lineatum.
 B. maculosum.
 B. mutabile.
 B. ventricosum.
 B. fasciatum.
 B. arcularia.
 B. pauperatum.
 B. achatinum.
 B. olivaceum.
 B. Brazilianum.
 B. vinosum.
 B. Ascanias.
 B. aciculatum.
 B. glaciale.
 B. annulatum.
 B. reticulatum.
 B. fuscatum.
 B. politum.
 B. inflatum.
 B. gemmulatum.
 B. miga.
 B. coronatum.
 B. neriteum.
 B. glans.
 B. canaliculatum.
 B. semiconvexum.
 B. corniculatum.
 B. Anglicanum.
 B. lævissimum.
 B. Tranquebaricum.
 B. lineolatum.
 B. suturale.
 B. retusum.
 B. Coromandelianum.
 B. lyratum.
 B. Thersites.
 B. testudineum.
 B. papillosum.
 B. tricarinatum.
 B. fasciolatum.
 B. subspinosum.
 B. flexuosum.
 B. cribarium.
 B. grana.
 B. zebra.
 B. aurantium.
 B. gibbolusum.
 B. marginulatum.
 B. coccinella.
 B. dermestoideum.
 B. pediculare.
 B. pullus.
 B. polygonatum.

        ·       ·       ·       ·       ·

 B. ornatum.*
 B. trivittata.*
 B. acuta.*
 B. alba.*
 B. vibex.*
 B. obsoleta.*
 B. unicincta.*
 B. lunata.*


                      10. Genus _Eburna_. Pl. XII.

_Animal._ Entirely unknown.

_Shell._ Oval or elongated, smooth; spire pointed, its whorls as if
softened off; aperture ovate, elongated, widely notched anteriorly; the
right margin entire; columella callous posteriorly, umbilicated, and
subcanaliculated at its left side; an operculum. Found in the Indian and
South American seas. Five species.

 Eburna glabrata.
 E. Ceylonica.
 E. spirata.
 E. areolata.
 E. lutosa.


                     11. Genus _Terebra_. Pl. XII.

_Animal._ Spiral and high; foot oval with a transverse anterior furrow,
and two lateral auricles; head bordered with a small fringe; tentacula
cylindrical, terminating in a point and very distant; eyes indistinct,
situated at the foot, and at the external side of the tentacula; mouth
without proboscis; tube of the respiratory cavity very long.

_Shell._ Without epidermis, ovate, with a pointed spire, low, or
subturriculated; aperture wide, oval, with a strong slope anteriorly;
lower end of the columella twisted. Found in tropical seas. Twenty-four
species.

 Terebra macalata.
 T. crenulata.
 T. dimidiata.
 T. raphanula.
 T. muscaria.
 T. flammea.
 T. striatula.
 T. chlorata.
 T. cerithina.
 T. subulata.
 T. oculata.
 T. Babylonica.
 T. Senegalensis.
 T. cingulifera.
 T. scabrella.
 T. lanceata.
 T. granulosa.
 T. duplicata.
 T. corrugata.
 T. cærulescens.
 T. myuros.
 T. strigilata.
 T. aciculina.
 T. vittata.


                               FAMILY XX.

                       COLUMELLARIA. Five genera.


                    1. Genus _Columbella_. Pl. XII.

_Animal._ Imperfectly known; eyes placed much below the middle of the
tentacula.

_Shell._ Thick, turbinated, with a short obtuse spire; aperture narrow,
elongated and terminated by a very short canal, narrowed by an inflation
at the inner side of the right edge, and by some folds on the columella;
a very small horny operculum. Inhabits the Indian and American seas.
Twenty species.

 Columbella rustica.
 C. Hebræa.
 C. semipunctata.
 C. reticulata.
 C. strombiformis.
 C. mercatoria.
 C. flavida.
 C. bizonalis.
 C. turturina.
 C. pardalina.
 C. ovulata.
 C. zonalis.
 C. mendicaria.
 C. punctata.
 C. scripta.
 C. nitida.
 C. fulgurans.
 C. unifascialis.

        ·       ·       ·       ·       ·

 C. labiosa.*
 C. avara.*


                       2. Genus _Mitra_. Pl. XII.

_Animal._ Entirely unknown.

_Shell._ Turriculated, subfusiform and oval; spire always pointed at the
summit; aperture small, triangular, widest anteriorly where it is
strongly emarginated; external edge trenchant, nearly straight, always
longer than the columella, which is formed by a very thin callosity, and
marked with oblique parallel folds, the anterior of which are the
shortest; no operculum. Inhabits the Chinese seas. Eighty species.

 Mitra papalis.
 M. puncticulata.
 M. cardinalis.
 M. versicolor.
 M. pedicula.
 M. cornicularis.
 M. striatula.
 M. cornea.
 M. melaniana.
 M. episcopalis.
 M. pontificalis.
 M. crocata.
 M. nexilis.
 M. scabrinscrula.
 M. crenifera.
 M. tæniata.
 M. corrugata.
 M. lyrata.
 M. cinctella.
 M. Caffra.
 M. stigmataria.
 M. fissurata.
 M. millepora.
 M. archiepiscopalis.
 M. sanguinolenta.
 M. lactea.
 M. lutescens.
 M. subulata.
 M. tringa.
 M. ferruginea.
 M. adusta.
 M. plicaria.
 M. costellaris.
 M. melongena.
 M. vulpecula.
 M. sanguisuga.
 M. filosa.
 M. ampliorella.
 M. patriarchalis.
 M. harpæformis.
 M. ficulina.
 M. conularis.
 M. dermestina.
 M. dactylus.
 M. conulus.
 M. coronata.
 M. muriculata.
 M. semifasciata.
 M. nucleola.
 M. plumbea.
 M. granulifera.
 M. clavula.
 M. Peronii.
 M. oniscina.
 M. terebralis.
 M. granulosa.
 M. costa.
 M. olivaria.
 M. granatina.
 M. serpentina.
 M. arenosa.
 M. literata.
 M. obliquata.
 M. scutulata.
 M. fenestrata.
 M. texturata.
 M. limbifera.
 M. paupercula.
 M. torulosa.
 M. retusa.
 M. unifascialis.
 M. larva.
 M. tabanula.
 M. crenulata.
 M. aurantiaca.
 M. cucumerina.
 M. ebena.
 M. microzonias.
 M. bacilla.
 M. pisolina.


                      3. Genus _Voluta_. Pl. XII.

_Animal._ Oval, involuted, provided with a very broad foot; head very
distinct; tentacula rather short and triangular; eyes large, altogether
sessile, and situated a little posteriorly; a thick trunk furnished with
hooked teeth at its extremity; two pectiniform branchiæ.

_Shell._ Oval, more or less ventricose; the first whorls of the spire
rounded into a teat; aperture generally much longer than wide and
sloping anteriorly; the right edge bent outwardly, entire and soft; the
columellar edge garnished with large folds more or less oblique, and
slightly varying in number with age. Found chiefly in the seas of the
Torrid Zone. Forty-four species.

 Voluta nautica.
 V. armata.
 V. tesselata.
 V. cymbia.
 V. proboscidalis.
 V. diadema.
 V. ducalis.
 V. Neptuni.
 V. olla.
 V. porcina.
 V. pellis-serpentis.
 V. chlorosina.
 V. polyzonalis.
 V. magnifica.
 V. Magellanica.
 V. fulminata.
 V. scapha.
 V. mitis.
 V. Braziliana.
 V. Guinaica.
 V. undulata.
 V. festiva.
 V. Æthiopica.
 V. imperialis.
 V. vespertilio.
 V. musica.
 V. levigata.
 V. nodulosa.
 V. ancilla.
 V. Pacifica.
 V. Junonia.
 V. melo.
 V. Hebræa.
 V. serpentina.
 V. carneolata.
 V. fulva.
 V. nuclea.
 V. Lapponica.
 V. volvacea.
 V. mitræformis.
 V. nivosa.
 V. thiarella.
 V. sulcata.
 V. vexilla.


                    4. Genus _Marginella_. Pl. XII.

_Animal._ Oval, involuted; foot elliptical, very large, and widest in
front, where its edge presents a transverse furrow; head small,
distinct, with two long, very sharp tentacula, the eyes at the external
part of their base; mouth provided with a trunk.

_Shell._ Smooth, polished, oval-oblong, a little conical, with a short
mammelonated spire; aperture somewhat narrow, slightly oval on account
of a light curve of the right edge, which is dilated outwardly; the
columellar edge marked with three oblique distinct folds. Inhabits the
Indian Ocean. Twenty-four living species and nine fossil, according to
Defrance.

 Marginella radiata.
 M. limbata.
 M. lifasciata.
 M. dentifera.
 M. bullata.
 M. avellana.
 M. glabrella.
 M. quinqueplicata.
 M. rosea.
 M. faba.
 M. dactylus.
 M. cornea.
 M. nubeculata.
 M. aurantia.
 M. longivaricosa.
 M. eburnea.
 M. persicula.
 M. tessellata.
 M. cærulescens.
 M. bivaricosa.
 M. muscaria.
 M. formicula.
 M. lineata.
 M. interrupta.


                     5. Genus _Volvaria_. Pl. XII.

_Animal._ As above.

_Shell._ Cylindrical, convolute; spire obsolete or concealed; aperture
narrow, extending the whole length of the shell, with one or more folds
on the lower portion of the columella. Inhabits the Indian Ocean. Seven
species.

 Volvaria pallida.
 V. monilis.
 V. miliacea.
 V. triticea.
 V. oryza.
 V. bulloides.
 V. canaliculata.


                              FAMILY XXI.

                         CONVOLUTA. Six genera.


                      1. Genus _Cypræa_. Pl. XII.

_Animal._ Oval, elongated, involute; head provided with two very long
conical tentacula; eyes at the extremity of an inflation which forms a
part of them; a transverse buccal orifice at the extremity of a kind of
cavity, at the bottom of which is the true mouth between two thick
vertical lips; a lingual band, bristled with small teeth, and prolonged
into the abdomen.

_Shell._ Oval, convex, very smooth, involute; spire entirely posterior,
very small, often concealed by a calcareous layer deposited by the lobes
of the mantle; aperture longitudinal, very narrow, slightly arcuated, as
long as the shell, and with the edges internally dentated, and notched
at each extremity. Inhabits the W. Indian seas and Sandwich Islands. One
hundred and eighteen species.

 Cypræa princeps.
 C. mappa.
 C. tigris.
 C. pantherina.
 C. mauritania.
 C. stercoraria.
 C. aurora.
 C. leucodon.
 C. sulcidentata.
 C. Arabica.
 C. lynx.
 C. vitellus.
 C. carneola.
 C. cinerea.
 C. Reevi.
 C. obscurus.
 C. achatina.
 C. arenosa.
 C. nivosa.
 C. Broderipii.
 C. exanthema.
 C. cervus.
 C. testudinaria.
 C. talpa.
 C. exusta.
 C. argus.
 C. scurra.
 C. pulchra.
 C. Isabella.
 C. controversa.
 C. lurida.
 C. dediculus.
 C. oryza.
 C. coccinella.
 C. Australis.
 C. Childrini.
 C. depauparata.
 C. solandri.
 C. Californica.
 C. suffusa.
 C. Pacifica.
 C. pediculus.
 C. nivea.
 C. oryxa.
 C. stercus-muscarum.
 C. pulex.
 C. fusca.
 C. Europea.
 C. sanguinea.
 C. quadripunctata.
 C. rufescens.
 C. maugeriæ.
 C. aperta.
 C. Adansonii.
 C. caput-serpentis.
 C. Lamarchii.
 C. Cumingii.
 C. Goodalii.
 C. Humphreysii.
 C. Walkeri.
 C. Listeri.
 C. pulchella.
 C. microdon.
 C. Scottii.
 C. mus.
 C. tessellata.
 C. annulata.
 C. Margarita.
 C. cicercula.
 C. globulus.
 C. staphylæa.
 C. tigrina.
 C. cerina.
 C. Argus.
 C. histrio.
 C. alba.
 C. zonata.
 C. icterina.
 C. lota.
 C. ovulata.
 C. helvola.
 C. Arabicula.
 C. pustulata.
 C. nucleus.
 C. limacina.
 C. moneta.
 C. obvelata.
 C. annulus.
 C. radians.
 C. oniscus.
 C. pyriformis.
 C. piperita.
 C. algoensis.
 C. edentula.
 C. similis.
 C. fusco-dentata.
 C. gangrenosa.
 C. bicallosa.
 C. poraria.
 C. guttata.
 C. Xanthodon.
 C. nigro-punctata.
 C. pallida.
 C. zigzag.
 C. moneta.
 C. aurantia.
 C. fimbriata.
 C. variolaria.
 C. erosa.
 C. miliaris.
 C. ratta.
 C. asella.
 C. turda.
 C. adusta.
 C. moniliaris.
 C. ursella.
 C. hirundo.
 C. olivacea.


                       2. Genus _Ovula_. Pl. XII.

_Animal._ As above.

_Shell._ Oblong, convex, distinguished from the Cypræa by the want of a
spire, and by not having teeth on the columellar lip; the two
extremities of the aperture notched, and more or less prolonged like a
tube; left margin dentated. Inhabits the Indian seas. Twelve species.

 Ovula oviformis.
 O. carnea.
 O. verrucosa.
 O. spelta.
 O. angulosa.
 O. hordacea.
 O. birostris.
 O. gibbosa.
 O. volva.
 O. lactea.
 O. triticea.
 O. acicularis.


                    3. Genus _Terebellum_. Pl. XII.

_Animal._ Entirely unknown.

_Shell._ Thin, shining, subcylindrical, involute, pointed posteriorly,
truncated anteriorly; aperture longitudinal, triangular; edges entire;
columella truncated, and prolonged beyond the aperture. Inhabits the
Indian Ocean. Three living species and two fossil.

 Terebellum subulatum.
 T. convolutum.
 T. fusiforme.


                    4. Genus _Ancillaria_. Pl. XII.

_Animal._ Unknown.

_Shell._ Smooth, oval, oblong posteriorly, widened and truncated
anteriorly; aperture oval, somewhat elongated, angular posteriorly; a
wide but not deep slope anteriorly; columella covered anteriorly with an
oblique callous band; right lip obtuse, Inhabits the Australian seas.
Four living species, and five fossil.

 Ancillaria cinnamonea.
 A. ventricosa.
 A. candida.
 A. marginata.


                       5. Genus _Oliva_. Pl. XII.

_Animal._ Oval, involute, mouth somewhat thin at its edges, prolonged to
the two angles of the branchial aperture in a tentacular band, and,
anteriorly, by a long branchial tube; foot very large, oval,
subauriculated, with a transverse cleft anteriorly; head small, with a
labial proboscis.

_Shell._ Thick, solid, smooth, oval, elongated, subcylindrical; the
whorls of the spire very small, and separated by a canal; aperture long
and narrow, the columellar edge dilated anteriorly by a band striated
obliquely in all its length. Found in the Australian and Equatorial
seas. Only one species has been found in America. Sixty-three species.
Six fossil.

 Oliva textilina.
 O. pica.
 O. angulata.
 O. sepulturalis.
 O. irrisans.
 O. episcopalis.
 O. venulata.
 O. leucophœa.
 O. inflata.
 O. harpularia.
 O. ustulata.
 O. tessellata.
 O. espidula.
 O. candida.
 O. tigrina.
 O. utricula.
 O. porphyria.
 O. erythrostoma.
 O. themulina.
 O. maura.
 O. fulminans.
 O. elegans.
 O. guttata.
 O. undata.
 O. bicincta.
 O. hepatica.
 O. avellana.
 O. carneola.
 O. oriola.
 O. volutella.
 O. Brazilliana.
 O. reticularis.
 O. granitella.
 O. literata.
 O. tricolor.
 O. mustelina.
 O. funebralis.
 O. Peruviana.
 O. fusiformis.
 O. acuminata.
 O. luteola.
 O. hiatula.
 O. Ceylonica.
 O. fabagina.
 O. undatella.
 O. nana.
 O. oryza.
 O. flammulata.
 O. araneosa.
 O. scripta.
 O. sanguinolenta.
 O. lugubris.
 O. glandiformis.
 O. senagalensis.
 O. auricularis.
 O. subulata.
 O. testacea.
 O. obtusaria.
 O. nebulosa.
 O. conordalis.
 O. eburnea.
 O. Zonalis.

        ·       ·       ·       ·       ·

 O. mutica.*


                       6. Genus _Conus_. Pl. XII.

_Animal._ Elongated, much compressed, involute; foot small, oval, long,
widest in front, where it is edged by a transverse furrow; head
tolerably distinct; tentacula cylindrical, having the eyes near their
summit, which is setaceous; mouth at the bottom of a long labial trunk;
a somewhat short tongue, although projecting into the visceral cavity,
and bristled with long styliform hooks in two rows.

_Shell._ Covered with a periosteal membrane, thick, solid, involute,
conical; summit of the cone anterior, spire slightly projecting, or not
at all; a very narrow longitudinal aperture; external edge straight and
trenchant; the internal also straight with oblique folds in its anterior
portion; a very small horny operculum, subspirated, with a terminal
summit. Found in the Australian and Mediterranean seas. One hundred and
eighty-one species.

 Conus Bandanus.
 C. Nicobaricus.
 C. zonatus.
 C. fuscatus.
 C. regius.
 C. marmoreus.
 C. nocturnus.
 C. araneosus.
 C. imperialis.
 C. viridulus.
 C. tulipa.
 C. punctatus.
 C. musicus.
 C. mus.
 C. Barbadensis.
 C. geographicus.
 C. tæniatus.
 C. miliaris.
 C. lividus.
 C. roseus.
 C. cedo-nulli.
 C. nebulosus.
 C. betulinus.
 C. puncticulatus.
 C. Proteus.
 C. augur.
 C. nivosus.
 C. acuminatus.
 C. Janus.
 C. lithoglyphus.
 C. venulatus.
 C. muscosus.
 C. Mozambicus.
 C. Franciscanus.
 C. rattus.
 C. amabilis.
 C. nobilis.
 C. terminus.
 C. gubernator.
 C. terebra.
 C. raphanus.
 C. spectrum.
 C. leoninus.
 C. pertusus.
 C. sulcatas.
 C. vermiculatus.
 C. pulicarius.
 C. obesus.
 C. millepunctatus.
 C. eburneus.
 C. generalis.
 C. Malacanus.
 C. monile.
 C. vitulinus.
 C. flavidus.
 C. daucus.
 C. capitaneus.
 C. vittatus.
 C. vexillus.
 C. figulinus.
 C. aurantius.
 C. minimus.
 C. Hebræus.
 C. arenatus.
 C. fustigatus.
 C. varius.
 C. literatus.
 C. tesselatus.
 C. Maldivus.
 C. lineatus.
 C. centurio.
 C. vulpinus.
 C. virgo.
 C. pastinacus.
 C. classiarius.
 C. mustelinus.
 C. Sumatrensis.
 C. quercinus.
 C. cardinalis.
 C. distans.
 C. Caledonicus.
 C. puncturatus.
 C. fulgurans.
 C. amadis.
 C. flammeus.
 C. testiludinarius.
 C. quæstor.
 C. Narcissus.
 C. guinaicus.
 C. informis.
 C. Jamaicensis.
 C. Omaicus.
 C. aurisiacus.
 C. striatus.
 C. grannulatus.
 C. verulosus.
 C. magus.
 C. Bullatus.
 C. auratus.
 C. omaria.
 C. panniculus.
 C. Timorensis.
 C. præfectus.
 C. nimbosus.
 C. archiepiscopus.
 C. legatus.
 C. canonicus.
 C. textilis.
 C. Australis.
 C. Mauritianus.
 C. eques.
 C. catus.
 C. acutangulus.
 C. Japonicus.
 C. columba.
 C. memocanus.
 C. fusiformis.
 C. Aurora.
 C. Adansonii.
 C. Portoricanus.
 C. lamellosus.
 C. exiguus.
 C. hyæna.
 C. ammiralis.
 C. papilionaceus.
 C. Promethæus.
 C. Suratensis.
 C. ranunculus.
 C. achatinus.
 C. stramineus.
 C. lacteus.
 C. vicarius.
 C. ochraceus.
 C. Mediterraneus.
 C. Magellanicus.
 C. pontificalis.
 C. sponsalis.
 C. Ceylonensis.
 C. pusillus.
 C. asper.
 C. miles.
 C. genuanus.
 C. siamensis.
 C. glaucus.
 C. monachus.
 C. anemone.
 C. cinereus.
 C. zebra.
 C. cingulatus.
 C. mercator.
 C. strigatus.
 C. mitratus.
 C. aulicus.
 C. colubrinus.
 C. auricomus.
 C. rubiginosus.
 C. prælatus.
 C. fumigatus.
 C. luzonicus.
 C. verrucosus.
 C. mindanus.
 C. pusio.
 C. madurensis.
 C. cancellatus.
 C. cærulescens.
 C. Taitensis.
 C. tinianus.
 C. crocatus.
 C. glans.
 C. nussatella.
 C. clavous.
 C. pennaceus.
 C. cervus.
 C. dux.
 C. stercus-muscarum.
 C. tendineus.
 C. melancholicus.
 C. episcopus.
 C. pyramidalis.
 C. abbas.
 C. gloria-maris.


                              FAMILY XXII.

                        NAUTILACEA. Two genera.


                      1. Genus _Spirula_. Pl. XII.

_Animal._ Body elongated, cylindrical, terminated posteriorly by two
lateral lobes partially concealing the shell; head provided with five
pairs of tentacula, of which two are longer than the others.

_Shell._ Very symmetrical, longitudinally twisted throughout nearly all
its extent; the cone spiral, conical, regular, circular; whorls of the
spire very evident; partitions simple, concave, and pierced by a single
syphon. Inhabits the West Indian seas. One species.

 Spirula Peronii. (Nautilus spirula. _Lin._)


                     2. Genus _Nautilus_. Pl. XII.

_Animal._ Body round and terminated posteriorly by a tendinous or
muscular filament, attaching itself to the syphon, by which the
partitions of the shell are pierced; the mantle opening obliquely, and
prolonged into a sort of hood above the head (which is provided with
digitated tentacula), and surrounding the aperture of the mouth.

_Shell._ Discoid, but slightly compressed, with a rounded or
subcarinated back, umbilicated or not, but never mammelonated, the
partitions simple, not visible exteriorly; the last profoundly sunk, and
perforated by a syphon running through them all. Inhabits the Indian
Ocean. Two living species. Fifteen fossil.

 Nautilus Pompilius.
 N. umbilicatus.


                             FAMILY XXIII.

                        HETEROPODA. Two genera.


                     1. Genus _Argonauta_. Pl. XII.

_Animal._ Body conical, elongated, enrolled longitudinally, widened
anteriorly, and provided on each side with an arcuated subtriangular,
aliform appendage; mouth at the extremity of the angle formed by two
inferior lips. De Blainville denies that this animal is at all known,
and speaks of one described by M. Oken as a small polypus of the genus
Ocythoe.

_Shell._ Navicular, symmetrical, very thin, compressed, bicarinated,
longitudinally subinvolute in the same plane; aperture very wide,
symmetrical, complete, square anteriorly, slightly modified by the turn
of the summit, and provided on each side with an ear-like appendage
having thick and smooth edges. Inhabits the Mediterranean. Three
species.

 Argonauta argo.
 A. tuberculosa.
 A. nitida.


                     2. Genus _Carinaria_. Pl. XII.

_Animal._ Body elongated, prolonged behind the nucleus into a veritable
tail, edged at its extremity by a vertical fin; head sufficiently
distinct; two, long, conical tentacula; two sessile eyes; the organs of
respiration and the nucleus entirely enveloped in a mantle with lobed
edges.

_Shell._ Very thin, symmetrical, a little compressed, without spire, but
with the summit a little reflexed posteriorly; aperture oval and entire.
Inhabits the African, Mediterranean, and Australian seas. Three species.

 Carinaria vitrea.
 C. fragilis.
 C. cymbium.




                                GLOSSARY
                      OF TERMS USED IN CONCHOLOGY.


                                     A.

  Abbreviated, cut short.

  Abdomen, the belly.

  Acuminated, sharp pointed.

  Aculeated, prickly.

  Alated, winged.

  Annulated, divided into rings.

  Annulations, rings.

  Aperture, the orifice or opening of the shell.

  Apex, the point of the spire.

  Approximating, approaching together.

  Arcuated, of an arch form.

  Area, surface between the lines.

  Articulations, junctures or joints.

  Attenuated, thin, slender.

  Aurated, having ears, as the Pecten.

  Auricled, having ear-like appendages.

  Auriform, ear-shaped.


                                     B.

  Barbed, bearded.

  Base, lower extremity of the shell.

  Beak, prolongation at the base.

  Beard, see Byssus.

  Bi, signifying two.

  Biangulated, having two corners or angles.

  Bidentate, having two teeth.

  Bifid, opening with a cleft.

  Bilobate, divided into two lobes.

  Bimarginate, two margins or lips.

  Biradiate, having two rays.

  Bivalve, having two valves.

  Blunt, obtuse, opposed to acute.

  Borer, a piercer.

  Bulging, gibbous, swollen out.

  Byssus, common in the Mytilus and Pinna, by which they attach
    themselves to objects.


                                     C.

  Callous, indurated.

  Callosity, a protuberance.

  Calcareous, relating to lime.

  Canal, the prolongation of the beak.

  Canaliculated, channeled or grooved.

  Cardinal, see Teeth.

  Carinated, like a boat’s keel.

  Cartilage, a flexible fibrous substance by which the valves are
    united.

  Cartilaginous, resembling a ligament.

  Chambered, divided by partitions.

  Cicatrix, the muscular impression.

  Ciliated, edged with bristles or hairs.

  Cinerous, of an ash colour.

  Clavate, club-shaped.

  Columella, the upright pillar of the shell.

  Complicated, doubled together.

  Compressed, flattened.

  Concave, hollowed out.

  Concentric, running to the centre.

  Cone, the form of a sugar loaf.

  Convolute, whorls running round.

  Confluent, running together.

  Conoid, figure like a cone.

  Contorted, twisted in oblique direction.

  Contracted, shortened, shrunk up.

  Cordate, heart shape.

  Cordiform, form of a heart.

  Coriaceous, leather-like consistence.

  Corneus, resembling horn.

  Coronal, resembling a crown.

  Coronated, crowned towards the apex.

  Costated, ribbed.

  Cortex, anterior skin.

  Crenulated, notched at the margin.

  Crispated, with waving lines.

  Cuneiform, wedge form.

  Cylindrical, round like a roller.

  Cybiform, boat-shaped.


                                     D.

  Decollated, truncated transversely.

  Decorticated, divested of epidermis.

  Decussated, lines intersecting each other.

  Deflexed, bent aside.

  Dentated, having teeth.

  Depressed, shallow, flat.

  Diaphanous, clear, pellucid.

  Digitated, having finger-like claws.

  Disk, the highest part of the valves.

  Divaricated, spreading out.

  Divergent, tending to a point.

  Dorsal, belonging to the back.

  Dotted, punctured like a thimble.

  Duplicated, divided into plaits or folds.


                                     E.

  Ears, projections on the sides of the hinge.

  Echinated, set with spires.

  Effuse, spread out.

  Elliptical, oval.

  Elongated, drawn out.

  Emarginated, with the edge notched.

  Ensisform, sabre-shaped.

  Entire, whole.

  Epidermis, the outer coating of a shell.

  Equilateral, all sides alike.

  Equivalve, both sides alike.

  Exserted, protruding.


                                     F.

  Falcated, hooped like a scythe.

  Fasciated, covered with bands.

  Ferruginous, of an iron colour.

  Filament, a thread-like process.

  Filiform, thread-shaped, slender.

  Fimbriated, fringed.

  Fissure, a cleft or slit.

  Flexuous, zigzag, with angles widening.

  Flexure, a bending.

  Fluviatile, belonging to fresh water.

  Foliaceous, lamina or leave-shaped.

  Fragile, brittle, easily broken.

  Front, the aperture next the observer.

  Furcated, forked.

  Furrow, a trench or hollow.

  Fuscated, darkened, obscured.

  Fusiform, spindle-shaped, conical, or oval.


                                     G.

  Gaping, when the valves do not close.

  Geniculate, keeled.

  Genus, characters by which they are distinguished from others.

  Genera, plural of genus.

  Gibbous, bulged.

  Glabrous, having a smooth surface.

  Globose, globular, round.


                                     H.

  Hemispherical, in the shape of a half globe.

  Heterostrophe, shells whose spires reverse.

  Hispid, hairy.

  Hinge, the part where the valves are united.


                                   I & J.

  Jagged, denticulated, uneven.

  Imbricate, covered with scales.

  Imperforate, having no umbilicus.

  Inequilateral, when the anterior and posterior parts of the shell are
    dissimilar.

  Inequivalve, when the valves are dissimilar.

  Inarticulate, indistinct.

  Incumbent, one lying over the other.

  Incurved, bent backward.

  Indented, unequally marked.

  Inflated, tumid, swollen.

  Inflected, bent inward.

  Inflexed, bent towards each other.

  Intercostal, placed between the ribs.

  Interrupted, divided, separated.

  Interstice, space between.

  Intortion, turning or twisting.

  Involute, without a spire.

  Involution, that part which involves another.

  Juncture, the joining of the whorl in univalves.


                                     K.

  Keel, the longitudinal prominence in the Argonauta.

  Keeled, see Carinated.


                                     L.

  Labra, the lips.

  Laciniate, cut in irregular segments.

  Lacunose, surface covered with pits.

  Lamellar, films on plates.

  Lamellated, divided into distinct plaits or foliations.

  Laminæ, thin plates, laid one above another.

  Lanceolate, oblong, tapering like the head of a lance.

  Lateral, extending to one side from the centre.

  Latticed, see Decussated.

  Lenticulate, doubly convex.

  Ligament, a solid body which connects the valves in bivalves.

  Linear, composed of lines.

  Linguiformed, tongue-shaped.

  Lip, the outer edge of the aperture of univalves.

  Lobated, rounded at the edges.

  Longitudinal, the length of the shell.

  Lunated, formed like a half moon.

  Lunule, crescent-like.

  Luniform, shape of a crescent.


                                     M.

  Margin, the whole circumference or outline of the shell in bivalves.

  Marginated, having a prominent margin or border.

  Membrane, a web of fibres.

  Mouth, see Aperture.

  Muscular impressions, marks made by the animal in adhering to the
    shell.

  Mottled, clouded or spotted.

  Mucronate, ending in a sharp point.

  Multilocular, many chambered.

  Muricated, clothed with sharp spines.


                                     N.

  Nacred, pearly.

  Nemoral, belonging to a wood.

  Nited, glossy.

  Nodose, knotty.

  Nucleus, a kernel.


                                     O.

  Obsolete, obliterated.

  Oblong, oval.

  Ocellated, eye-like spots.

  Ochreous, colour of yellow ochre.

  Offuscated, darkened, clouded.

  Olivaceous, of a greenish olive colour.

  Operculum, which closes the aperture of the shell.

  Orbicular, circular, round.

  Orifice, an opening or perforation.

  Ovate, shaped like an egg.

  Ovoid, oval.


                                     P.

  Papillose, pimple, dotted.

  Papyraceous, thin as paper.

  Patulous, with a gap or opening.

  Partitions, processes dividing the shells of the Nautilus, Serpula,
    &c.

  Pectinated, resembling the teeth of a comb.

  Pedicle, the support of the Anatifera and its corresponding species.

  Peduncle, a tube on which any thing is seated.

  Pellucid, transparent, clear, bright.

  Pentagonal, having five sides.

  Perforated, pierced with holes.

  Pervious, admitting passage.

  Pillar, in univalves the internal continuation of the columella or
    inner lips, extending from the _base_ to the _apex_.

  Pinnated, winged.

  Plaited, folded.

  Plaits, folds.

  Plicated, folded or plaited.

  Posterior, see Margin.

  Produced, lengthened out.

  Protrude, to thrust forward.

  Punctuated, like the punctures of a thimble.

  Pyriform, pear-shaped.


                                     Q.

  Quadrangular, having four right angles.

  Quadruplicated, having four plaits.


                                     R.

  Radiated, furnished with rays.

  Radicated, fixed by the base to another body.

  Rectangular, having right angles.

  Recurvated, turned backward.

  Recurved, bowed back.

  Reflected, bent backward.

  Refracted, abruptly bent.

  Reniform, kidney-shaped.

  Replicated, folded or plaited.

  Reticulated, formed like a piece of net-work.

  Retuse, ending in an obtuse sinus.

  Reversed spire, see Heterostrophe.

  Revolute, rolled backward.

  Ribbed, having longitudinal ribs.

  Ridge, the upper part of a slope.

  Rostrum, the beak.

  Rugose, wrinkled.


                                     S.

  Sanguinaceous, divided into chambers.

  Scabious, rough, rugged.

  Scalloped, indented at the edges.

  Scutellated, shield-shaped.

  Seam, line formed by the union of the valves.

  Semi, the half.

  Semi-cordate, half heart-shaped.

  Semi-orbicular, shape of a half globe.

  Semi-lunar, shape of a half moon.

  Septiform, shape of a partition.

  Serrated, like the teeth of a saw.

  Sessile, sitting or seated.

  Seta, a bristle.

  Setaceous, covered with bristles.

  Setiferous, bearing bristles.

  Sinister valve, is the left valve.

  Sinus, a groove or cavity.

  Siphunculus, a cylindrical perforation as in the Nautilus, Spirula,
    &c.

  Spatulate, rounded and broad at the top.

  Species, the division of a family or genus.

  Spiny, thorny.

  Spinous, like a hedgehog.

  Spire, all the whorls in univalves except the one in which the
    aperture is situated, which is termed the body.

  Spiral, twisted like a corkscrew.

  Squamose, scaly.

  Striated, covered with thread-like lines.

  Sub, almost.

  Subarcuated, somewhat arched.

  Subconic, somewhat conical.

  Subulate, awl-shaped.

  Sulcated, furrowed.

  Summit, the tip or apex.

  Suture, a hollow line of division in univalves, the spiral line of
    which separates the wreaths.


                                     T.

  Teeth, pointed protuberances within the hinge in bivalves by which the
    valves are united.

  Tentacula, the feelers of snails, which inhabit shells.

  Tessellated, chequered like a chess board.

  Testacea, that order of animals covered with a testaceous shell.
    Testaceous, consisting of carbonate of lime and animal matter.

  Tortuosity, flexure.

  Tortuous, twisted.

  Transverse, crossways.

  Trapeziform, shaped like a trapezium.

  Trigonal, having three angles.

  Truncated, cut short, ending abruptly.

  Tubercle, knot or pimple.

  Tuberculated, knotted, pimpled.

  Tubular, in the shape of a hollow tube.

  Tunicated, coated.

  Turbinated, shape like a top or pear.

  Turgid, swollen.

  U and V.

  Valves, the various pieces which compose the shell.

  Varices, longitudinal ribs in univalve shells.

  Variety, difference in species.

  Vaulted, roofed.

  Ventral, belonging to the belly.

  Ventricose, inflated, swelled in the middle.

  Vermiform, worm-shaped.

  Vertex, the top of a most prominent part.

  Verrucose, warted.

  Verticulated, whorled.

  Umbilicated, having a depression in the centre.

  Umbo, the round part which turns over the hinge.

  Undulated, waved.

  Ungulata, shaped like a horse’s hoof.

  Unilocular, chambered singly.

  Univalve, shells of one valve only.

  Volutions, the turnings of univalves.


                                     W.

  Whorl, a spiral convolution.


                                     Z.

  Zigzag, having reverse turnings and windings.

  Zoned, surrounded by belts or girdles.




                                 INDEX


                                   A.

 Acasta, 32

 Acera, 95

 Achatina, 102

 _Alata_, 135

 Amphidesma, 44

 _Amphitritea_, 27

 Amphitrite, 28

 Ampullaria, 113

 Anostoma, 103

 Anatifera, 33

 Anatina, 40

 Ancillaria, 150

 Ancylus, 94

 ANNULATA, 25

 Anodonta, 69

 Anomia, 83

 _Aplysiacea_, 96

 Aplysia, 96

 Arca, 62

 Arenicola, 25

 _Arcacea_, 62

 Argonauta, 155

 Aspergillum, 35

 Auricula, 107

 Avicula, 76


                                   B.

 Balanus, 31

 Bivalve shells, 10

 _Brachiopoda_, 84

 Buccinum, 141

 Bulimus, 105

 Bulla, 95

 _Bullacea_, 95

 Bullæa, 95


                                   C.

 _Calyptracea_, 91

 Calyptræa, 93

 _Canalifera_, 127

 Cancellaria, 130

 Capsa, 53

 _Cardiacea_, 59

 Cardita, 60

 Cardium, 59

 Carinaria, 156

 Carocolla, 102

 Cassidaria, 137

 Cassis, 138

 Castalia, 65

 Chama, 70

 Cerithium, 127

 _Chamacea_, 70

 Chiton, 88

 Chitonellus, 88

 Cineras, 33

 CIRRHIPEDA, 30

 _Cirrhipeda_, 30

 Classification, 21

 Clausilia, 105

 Clavagella, 35

 Cleodora, 87

 Clio, 86

 Clymene, 26

 _Colimacea_, 99

 Columbella, 143

 _Columellaria_, 143

 _Conchacea_, 53

 _Convoluta_, 147

 CONCHIFERA, 34

 Conus, 152

 Corbis, 51
 Corbula, 45

 _Corbulacea_, 45

 Concholepas, 140

 Coronula, 31

 Crania, 84

 Crassatella, 43

 Crassina, 53

 Crenatula, 75

 Crepidula, 94

 Creusia, 32

 Cucullæa, 63

 Cyclas, 57

 Cyclostoma, 107

 Cymbulia, 87

 Cyrena, 58

 Cypræa, 147

 Cypricardia, 61

 Cyprina, 53

 Cytherea, 54


                                   D.

 Delphinula, 121

 Dentalium, 26

 Diceras, 70

 Dolabella, 96

 Dolium, 141

 Donax, 52

 _Dorsalia_, 25


                                   E.

 Eburna, 142

 Emarginula, 92

 Erycina, 43

 Etheria, 71


                                   F.

 Fasciolaria, 130

 Fissurella, 92

 Fistulana, 35

 Fusus, 131


                                   G.

 Galathea, 58

 Galeolaria, 29

 Gastrochæna, 37

 Glycimeris, 39

 Gryphea, 82


                                   H.

 Haliotis, 118

 Harpa, 140

 Helicina, 103

 Helix, 99

 _Heteropoda_, 155

 Hiatella, 61

 Hippopus, 72

 Hyalea, 86

 Hyria, 68


                                   I.

 Iridina, 70

 Isocardia, 61


                                   J.

 _Janthinea_, 117

 Janthina, 117


                                   L.

 Lima, 78

 _Limacina_, 97

 Limacina, 87

 Limax, 97

 Lingula, 85

 _Lithophaga_, 46

 Lucina, 51

 Lutraria, 41

 _Lymnacea_, 108

 Lymnea, 108


                                   M.

 _Mactracea_, 41

 Mactra, 41

 _Macrostomiana_, 117

 Magilus, 30

 _Malleacea_, 75

 Malleus, 76

 _Maldania_, 26

 Marginella, 146

 _Melaniana_, 110

 Melania, 110
 Melanopsis, 111

 Meleagrina, 77

 Mitra, 144

 Modiola, 74

 MOLLUSCA, 85

 Monoceros, 140

 Monodonta, 123

 Murex, 133

 Multivalves, 9

 _Myaria_, 40

 Mya, 40

 Mytilus, 73

 _Mytilacea_, 73


                                   N.

 Naiadea, 66

 Natica, 116

 _Nautilacea_, 150

 Nautilus, 155

 Navicella, 115

 Nerita, 115

 Neritina, 114

 _Neritacea_, 114

 Nucula, 64

 _Nymphacea_, 48


                                   O.

 Oliva, 150

 Onchidium, 98

 Orbicula, 84

 Ostrea, 80

 _Ostracea_, 80

 Otion, 34

 Ovula, 149


                                   P.

 Paludina, 112

 Parmacella, 98

 Parmophorus, 91

 Patella, 90

 Pandora, 45

 Panopea, 38

 Pecten, 78

 Pectinaria, 27

 Pectunculus, 63

 Pedum, 77

 _Pectinea_, 77

 _Peristomiana_, 112

 Perna, 76

 Petricola, 47

 Phasianella, 126

 Pholas, 37

 _Pholadaria_, 37

 Physa, 109

 Phyllidia, 88

 _Phyllidiacea_, 88

 Pirena, 111

 Pinna, 74

 Pileopsis, 93

 Planorbis, 109

 _Plicacea_, 119

 Planaxis, 125

 Placuna, 83

 Pleurotoma, 128

 Pleurobranchus, 91

 Plicatula, 80

 Plagiostoma, 79

 Pneumodermon, 87

 Pollicipes, 33

 Podopsis, 80

 Psammobia, 48

 Psammotea, 49

 Pteroceras, 136

 _Pteropoda_, 86

 Pupa, 104

 Purpura, 139

 _Purpurifera_, 137

 Pyramidella, 120

 Pyrula, 132

 Pyrgoma, 32


                                   R.

 Ranella, 133

 Ricinula, 138

 Rostellaria, 135

 Rotella, 127


                                   S.

 Sabellaria, 27

 Sanguinolaria, 48

 Saxicava, 46

 Scalaria, 120

 _Scalarina_, 120

 Septaria, 36

 Serpula, 28

 _Serpulacea_, 28

 Sigaretus, 117

 Siliquaria, 25

 Solarium, 121

 Solecurtus, 39

 Solen, 38

 _Solenea_, 38

 Solenaria, 48

 Solemya, 44

 Spirorbis, 28

 Spirula, 154

 Spondylus, 80

 Stomatella, 118

 Stomatia, 118

 Strombus, 136

 Struthiolaria, 132

 Succinea, 106


                                   T.

 Tellina, 49

 Tellinides, 51

 Terebella, 27

 Terebellum, 150

 Terebra, 143

 Terebratula, 84

 Teredo, 36

 Teredina, 36

 Testacella, 98

 Tornatella, 119

 Trochus, 122

 Tridacna, 72

 _Tridacnea_, 72

 Trigonia, 65

 _Trigonacea_, 65

 Triton, 135

 _Tubicola_, 35

 Tubicinella, 30

 Turbo, 124

 _Turbinacea_, 121

 Turbinella, 129

 Turritella, 126


                                   U & V.

 Umbrella, 91

 Ungulina, 43

 Unio, 66

 Univalves, 14

 Valvata, 112

 Venericardia, 57

 Venerirupis, 47

 Venus, 55

 Vermilia, 29

 Vermetus, 121

 Vitrina, 97

 Voluta, 145

 Volvaria, 147

 Vulsella, 80


                                THE END.

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                          TRANSCRIBER’S NOTES


 1. Silently corrected typographical errors and variations in spelling.
 2. Archaic, non-standard, and uncertain spellings retained as printed.
 3. Enclosed italics font in _underscores_.