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TO THE READER OF THIS 
VOLUME 

Kindly handle this book with the utmost 
care on account of its fragile condition. 
The binding has been done as well as pos- 
sible under existing conditions and will 
give reasonable wear with proper opening 
and handling. 

Your thou ghtf ulness will be appreciated 








.; ////„.y, 



Division of 
Sectional L&rary 



CONCHOLOGICAL MANUAL. 



BY 



G. B. SOWER BY, Jun. 



ILLUSTRATED BY UPWARDS OF SIX HUNDRED AND SIXTY FIGURES. 



THIRD EDITION, 



CONSIDERABLY ENLARGED AND IMPROVED. 



LONDON: 

HENRY G. BOHN, YORK STREET, COVENT GARDEN. 
MDCCCXLVf. 



S7: 
StNHTO 



M<a£, 



PREFACE TO THE FIRST EDITION. 



It may be necessary in introducing this little volume, to 
state, that it is strictly conchological, and that it is compiled 
for the use not only of those who wish to acquire an elementary 
acquaintance with the subject, but also of authors and others, 
who, desirous of extending their knowledge and pursuing their 
researches, require a book of reference, containing a general 
outline of what has been done by those who have trodden the 
same path before them. It has been thought advisable, for 
general convenience, to arrange the principal part of the 
information in alphabetical order; adding tables of the sys- 
tems of Lamarck and De Blainville, to facilitate the systematic 
pursuit of the science. 

Persons of the class first alluded to, will find great assistance 
in the explanation of technical words, their application being 
further illustrated, in most cases, by a reference to the figures ; 
and, although they might have been multiplied, it is trusted 
that enough are given for every useful purpose. 

The definition of the Classes, Orders, Families, and Genera, 
in the system of De Blainville, and a tabular view, are pre- 
sented for the use of those who prefer it, or who wish to com- 
pare it with that of Lamarck. 

In the explanation of the figures, will be found a systematic 
arrangement of shells, according to Lamarck, including the 
names of genera established or proposed since the publication 
of his system. The descriptions of established genera have 



IV PREFACE, 



been rendered as concise and clear as possible. It is hoped 
that no essential characters are omitted, and that those living 
authors, whose proposed generic distinctions have been passed 
over in a few words, will not have to complain of want of 
justice in the attempt to interpret their meaning. 

In most cases the generic name will be found accompanied 
by its derivation. This has been done, in the hope of assisting 
the memory by associating the meaning of a term with some 
peculiarity in the thing described. At the end of each de- 
scription of a genus, some general observations occur, pointing 
out the principal character which distinguishes it from others, 
to which it is nearly allied ; and also stating the geographical 
or geological distribution and habits of the animal. 

The above descriptions and definitions are illustrated by a 
series of plates, containing above 500 etchings of nearly as 
many proposed or established genera, arranged in Lamarckian 
order, so as to show at a glance all the generic forms of each 
family. And, although from their number, they could not be 
very highly finished, it is hoped that they will be found cha- 
racteristic. 

The compiler cannot replace his pen without acknowledging, 
with filial gratitude, the kind assistance of one who has sacri- 
ficed much of his time in bringing his knowledge and expe- 
rience to bear upon the correctness and utility of this humble 
attempt to remove some of the difficulties to which the com- 
mencement of this, as well as of every other study, is exposed. 



PREFACE TO THE SECOND EDITION. 



The favourable reception and rapid sale of the first edition 
of the Conchological Manual having rendered a second neces- 
sary, the Author takes this opportunity of explaining the 
nature of the alterations which have been made. In doing 
this, he has to thank his friends for their suggestions, which, 
together with his own increased knowledge and experience, 
enable him to present a more complete and satisfactory work 
to the scientific public. 

For the further convenience of those who are studying the 
rudiments of the science, an entirely new Introduction is 
given, in which, commencing with the structure and gradual 
developement of the shell, the author has endeavoured to 
explain the general principles of Conchology in systematical 
order. This Introduction is illustrated by 100 wood-cuts, 
which will be found greatly to assist the Student. 

The definitions have been rendered more full and complete 
than before, and the Author has profited by some manuscript 
notes communicated by a scientific friend, to whom he desires 
to present his humble acknowledgments. Upwards of four 
hundred explanations have been given of words which did not 
appear in the former edition, three-fourths of which are of 
generic and subgeneric names. 

A large number of notes, referring to the geographical 
distribution of the genera, have been added from the pen of 
Mr. G. B. Sowerby, Senior. 



VI PREFACE. 

The plates have been carefully improved ; and three, 
containing upwards of eighty figures, have been added. 

On the whole, it will be found that the amount of matter 
has been nearly doubled ; all the defects, as far as they have 
been discovered, have been removed, and every means used 
of making the present edition as useful as possible. 



NAMES OF AUTHORS ABBREVIATED. 



Adans. Adanson. Author of " Voyages du Senegal." 

Bl. Blainville. Author of " Manuel de Mulaeologie et de Conchyliologie," &e. 

Brod. W.J. Broderip, Esq. Author of various descriptions of Shells in the 

Zoological Journal, &c. 
Brongn. Brongniart. Author of " Memoire sur les terrains du Vieentin, d'ltalie, 

de France, et d'Allemagne," &c. 
Brug. Brugiere. Author of '• Dictionaire des Vers testac6s, dans l'Encyclo- 

pedie," &c. 
Cuv. The late Baron Cuvier. Author of " Regne Animal," &c. 
Defr. Defrance. Contributor to the " Annales des Sciences Naturelles," &c. 
Desh. Deshayes. Author of " Coquilles fossiles des environs de Paris/' &c. 
B'Orb. D'Alcide D'Orbigny. 
Drop. Draparnaud. Author of •' Histoire Naturelle des Mollusques terrestres 

et fluviatiles de la France," &c. 
Fer. De Ferussac. Author of u Histoire Naturelle des Mollusques terrestres 

et fluviatiles," &c. 
Flem. Fleming. 

Gmel. Gmelin. Author of an edition of Linnseus's " Systema Naturae," &c. 
Guild. Rev. Lansdown Guilding. 
H'ubn. Hiibner. 

Humph. The late George Humphrey. 

Lam. Lamarck. Author of " Animaux sans Vertebres," &c. 
Lin. Linnseus, Author of " Systema Naturae," &c. 
Mont. Montague. Author of " Testacea Britannica," &c. 
Montf. Montfort. Author of " Histoire Naturelle des Mollusques," &c. 
Mull. Muller. Author of "Vermium terrestrium et fluviatilum," " Zoologiae 

Danica?," &c. 
Ranz. Ranzani. Author of u Considerations sur les Balanes," &c. 
Schum. Schumacher. 
Sow. Sowerby. The late James. Author of "Mineral Conchology," &c. 

George Brettingham, Senr., "Genera of Shells," " Species Conchy liorum," 

&c. G. B. Jun. " Conchological Manual," " Conchological Illustrations," 

" Thesaurus Conchyliorum," Descriptions of New Shells in the Zoological 

Proceedings, &c. 
Sw. Swainson. Author of " Zoological Illustrations," " Exotic Conchology," 

" Lardner's Cabinet Cyclopedia," &c. 
Turt. Turton. Author of " British Shells." 



INTRODUCTION. 



The Science of Conchology affords a very delightful and in- 
structive amusement for the leisure hours of those who, retiring 
occasionally from the gaieties of fashionable life, seek pleasure 
in the quiet contemplation of some of the smaller, but not less 
wonderful operations of creative wisdom. And, although the 
study of shells would be more complete, and rank higher in 
the scale of philosophical pursuits, were it always accompanied 
by that of the animal inhabiting them, it nevertheless presents 
means of intellectual gratification, to many who cannot follow it 
beyond the cabinet and the boudoir. These may examine 
with admiration and mental improvement, the beautiful 
colouring and architecture of these wonders of the deep, they 
may exercise their taste and judgment in the selection and 
arrangement of specimens, and their discrimination in detect- 
ing and appreciating the distinctions upon which the arrange- 
ment is founded. 

It is but little that can be known of the subject without 
forming a collection of greater or less extent ; for, as it would be 
uninstructive merely to delight the eye with the bright colours 
and elegant form of shells, without possessing correct infor- 
mation respecting them, so it would be insipid and useless to 
learn technicalities without being acquainted by personal obser- 
vation with the subjects to which they are applied. The first 
endeavour should, therefore, be to obtain a few shells as 
examples of the larger divisions, and, when these are understood, 
to proceed with the smaller groups, until a collection be formed 
to represent as many generic forms as possible. It may be as 

B 



« INTRODUCTION. 

well here to advise those who are forming a collection to be 
very particular in every practicable instance to have the shells 
properly named at the time of purchasing; as it will save 
much trouble, and materially assist in the attainment of the 
desired object. To this end, recourse should be had to those 
naturalist tradesmen, who unite the attainment and diffusion 
of real scientific knowledge with their commercial pursuits. 

Supposing, however, that the person who desires to learn 
the science, possesses a small parcel of unarranged and 
unnamed shells, without any previous acquaintance with the 
subject, the following introductory explanations, are drawn up 
with the view of enabling him, without further assistance, to 
obtain a general insight into its principles, equal to that of 
those who have studied it long and laboriously. To effect 
this, he must read them, carefully comparing the descriptions 
with the figures referred to, and with the specimens which he 
may have at command. 

After describing the nature of the science and defining its 
objects, we shall proceed to explain the structure of those 
objects, and the manner of their growth. We shall then enter 
somewhat minutely into the principles of classification, the 
distinctions upon which they are founded, and some of the 
technical terms used to express them. After which we shall 
pass through the arrangement of Lamarck, defining the general 
divisions adopted under the terms of " Classes, Orders, and 
Families" as far as they are capable of definition. The sub- 
division of the latter into genera will only be entered into so far 
as to enumerate the principal of them, the more minute de- 
scriptions being reserved for the alphabetical part of the work. 

Let none be discouraged by the number of generic dis- 
tinctions proposed and adopted in modern times ; for if well 
defined, they will be found to facilitate rather than encumber 
the science. The knowledge of species must be the foundation 



DSI 



INTRODUCTION. O 

of every system, and the greater their number, the more 
necessary it becomes to subdivide them ; if, for instance, all the 
species now known were to have been included in the 50 
genera of Linnaeus, a single genus would have contained many 
hundreds of incongruous species, in which case it would be 
much more difficult to remember them, than if they were to 
be divided into a far greater number of genera. Every well 
marked division, however arbitrary its limits, tends to simplify 
the subject, and to facilitate the researches of the student. 

NATURE OF THE SCIENCE. 

Conchology is the study of shells, viewed and described 
as to what they are either in themselves, or in relation to the 
soft, inarticulate animals which produce them, and of which they 
form a part. These animals are called Mollusca, and perhaps 
the best general description of them will be found in De 
Blainville's " Manuel de Malacologie et de Conchy liologie." 
The following is a translation, " Animal in pairs, the body and 
its appendages soft, inarticulate (not jointed), enveloped in a 
muscular skin, commonly called the mantle, which is extremely 
variable in form, and has developed either within or upon it 
a calcareous portion, consisting of one or several pieces, 
commonly called a shell." 

The term Mollusca was formerly restricted to those soft 
animals which were destitute of shells, although possessing 
in other particulars, the characters described above, and it was 
used in order to distinguish them from the Testacea, which 
were covered or internally supported by calcareous parts. In 
the system of Linnaeus, the soft portions are first arranged 
under the general designation of " Vermes Mollusca,'' and de- 
scribed without regard to the presence, absence, or character 

of the shells ; and then the shells are separately characterized 

b 2 



4 INTRODUCTION. 

under the appellation of " Vermes Testacea," without any 
further notice of the animal, than an indication of the genus to 
which it belongs ; thus the animal of Cyprsea is said to be a 
Limax, and that of Tellina a Tethys. 

The nearest approach to correctness, and the most philoso- 
phical method of study will be found in the modern system, 
adopted by Lamarck and his followers, of observing these 
animals as a whole, and arranging them according to the 
assemblage of characters which they present ; of course taking 
into consideration the existence or non-existence, form and 
structure of the shell, on the same principle, which, in 
arranging the vertebrated animals would lead us to study the 
hair, hoof, nails, claws, &c. as well as the other parts. 

At the same time, it must be admitted that there are many 
private collectors of Shells who would find it a difficult, if not 
impossible task to study minutely and successfully the soft 
parts of the Mollusca. Ladies, for instance, could not be 
expected to handle with pleasure and perseverance, these 
fleshy substances, which in order to be preserved from putre- 
faction, must be kept in spirits ; and yet such persons may, 
with improvement and advantage to their own minds, enjoy 
the interesting and scientific amusement of studying and 
arranging the clean and beautiful natural objects which are so 
easily preserved, and so exquisitely curious in their structure. 
Let it also be remembered, that if shells had not been rendered 
commercially valuable, by the zeal and emulation manifested 
by mere Conchologists for the possession of rare specimens, 
few travelling merchants and sea captains would have thought 
them worthy of a corner in their cabins. In this case, few 
specimens being brought to the country, the more Philosophical 
Naturalist would have been left without the means of obtain- 
ing materials to work upon, or of attracting public attention to 
his favourite pursuit. 



INTRODUCTION. 5 

On account of these and other considerations, it has been 
thought advisable that the present undertaking should bear a 
purely conchological character. The peculiarities of the shells 
alone being detailed for the assistance of those who collect and 
study them, while at the same time, in deciding upon their 
affinities and places, in the arrangement, it will be necessary to 
take advantage of the conclusion to which those have arrived, 
who have studied the animal in all its parts. And the con- 
viction must be expressed, that if ever a complete Natural 
System shall be formed it will result from the labours of the 
last mentioned class of naturalists. 

DEFINITION OF A SHELL. 

Before entering minutely into the description of shells, it 
will be necessary to distinguish from the true testaceous 
Mollusca two kinds of animals which have formerly been 
associated with them. Of these, the first is the class of 
Crustacea, consisting of crabs, crayfish, &c. These differ 
from shell-fish, not only in structure and chemical composition, 
but also in the fact that the animal has jointed limbs, and that 
the substance of the flesh is inseparable from the hard ex- 
ternal covering, which invests each particular joint as with a 
sheath ; whereas the Molluscous animal is but partially at- 
tached to its shell, from which it possesses the power of partly 
withdrawing and returning. The second class is that to which 
the sea-urchin, or Echinus, belongs, of which there are many 
genera and species. The testaceous covering of Echini is 
composed of a number of small pieces, placed edge to edge, 
forming a more or less globular external covering to the flesh, 
which is supported in the centre by a number of bones leaning 
upon each other in a pyramidal form. The test is of a fibrous 
texture, guarded on the outside with moveable spines, which 
turn on ball and socket joints. 



b INTRODUCTION. 

A true shell is composed of one or more calcareous pieces, 
commonly called valves, each piece formed by a series of 
layers, applied obliquely upon each other, in such a manner 
that each new layer begins within, and terminates a little in 
advance of the one before it, 



STRUCTURE AND GROWTH. 

We shall now endeavour to describe the manner in which 
the growth of each separate valve, or each regularly formed 
shell, proceeds from the nucleus. 

Before the young animal has left the egg, if it be an 
oviparous species, or the body of the parent if viviparous, the 
nucleus of the shell is generally formed, and specimens are 
sometimes preserved in which the young shell is seen within 
the egg, as in the cut, fig. 1, 2 ; or adhering to the inner sur- 
face of the full-grown shell by the dried mucus of the animal, 
as seen in fig. 3. 




1. Egg of aBulinus. 2. The same broken, shewing the 
young shell. 3. The young of a Paludina, as seen in 
the aperture of the shell. 

In both cases, the nucleus is generally of a more horny and 
transparent composition than the parts subsequently produced. 
As soon as the animal is hatched, or, in other words, leaves 
the egg or body of the parent, of course it begins to increase 
in size, and to require a corresponding enlargement in the 



INTRODUCTION. / 

shell. To effect this, a small quantity of mucus substance, 
secreted by the mantle of the animal, is deposited on the edge 
of the aperture. When this is dry and become sufficiently 
hard, it is lined by a more calcareous secretion ; and these 
together form a new layer, which is followed by others in 
succession ; each new layer being larger than the one that 
preceded it until the whole being complete, the full-grown 
animal is invested with a shell commensurate with its own 
proportions. Thus from the apex or nucleus the formation 
proceeds, as it were, downwards, taking the shape of the part 
which secretes it, on which it is in a manner moulded. 
i The nucleus, or first formed portion, may for technical pur- 
poses be considered, mathematically, as the apex of a spiral 
cone. And here it must be observed, that whether the shell 
consist of one or several pieces, each piece has a separate 
nucleus, and the process of formation is separately repeated 
with each. The word cone is used for convenience, and its 
meaning extended so as to include all those structures which 
commencing at a point enlarge downwards. 

From the apex, the next layer is deposited on its edge, and 
advancing beyond it necessarily adds to its extent. Thus, 
suppose for the sake of illustration, the w^-^ 
part marked a in the diagram, fig. 4, r /V/x^X 
to represent a nucleus, the cross lines (7) fe'0/^^^\ 
will shew the consecutive layers, which ^'?V^--— ^ 

enlarge their circle as they add to their ^X^^ ^A 

numbers. This disposition of shelly it^S?^ 

matter into layers is marked externally /a 
by concentric striae, orlines of growth, 4 - imaginary cone. 
while on the inside the edges of the b ] Base# 
laminae are consolidated into a kind of l - Lines of growth. 
enamel. If a perpendicular section of a solid portion of a 
shell were magnified, it would present, in many instances, an 



^ 




Supposed section of a part of a 
solid shell. 



O INTRODUCTION. 

appearance resembling the diagram, fig. 5 ; a may be taken 
to represent the horny part of 
the layers which form the outer 
coating, named " Periostaca," 
or "Epidermis;" the undula- 
ting line b, is formed by the 
edges of the calcareous layers, 
and causes the striae, or lines of growth, which are often dis- 
tinguishable on the surface of the shell ; the space c is the 
middle part of those layers, and at d they are consolidated 
into the enamel which lines the interior. 

In some species the layers are irregularly grouped together, 
and their edges overlap each other, so that they are easily 
separable, and advancing beyond each other, give a leafy 
appearance to the external surface. This structure is termed 
foliaceous. A very familiar instance of this may be observed 
in the common oyster. If a specimen of this shell be broken, 
the substance will be seen to exhibit a degree of looseness, and 
a magnifying glass will enable the student to trace distinctly 
the laminae of which it is composed. The accompanying re- 
presentation of a magnified section (fig. 6) will shew at 
a, the external surface, with 
the foliations or leaves ; at b, 
the parcels of layers which 
form them ; and at c, the 
pearly structure produced by 
their consolidation, and by the 6> Section of an °y ster sheU enlar S ed - 
subsequently deposited enamel which covers their external 
surface. 




CLASSIFICATION. 

The classification of shells, that is, their systematic arrange- 
ment into classes, orders, families, genera and species, cannot 



INTRODUCTION. V 

be made to depend entirely upon the characters observable in 
them, viewed by themselves ; for this reason, that many simi- 
larly formed shells form the habitations of animals perfectly 
distinct, and that many molluscous animals are found to agree 
with each other in every respect but in the form of their 
testaceous support. There are, however, many important dis- 
tinctions to be observed in the shells themselves, leading to the 
establishment of many of those very divisions, which would 
afterwards be confirmed by an examination of the soft parts. 
It is necessary to attend, as far as means and opportunity will 
allow, to all the points of difference, both in the shell and in 
the animal, in order to form, and in some instances even to 
appreciate, a generic or larger distinction. It will therefore be 
our endeavour to explain the general principles upon which 
those distinctions are formed, and the manner in which they 
are applied and expressed in detail by scientific writers. 



NUMBER OF PIECES, OR INDEPENDENTLY 
FORMED PARTS. 

The first, most simple and obvious division of shells, is that 
which results from the number of separate pieces composing 
them. Hence the distinction implied by the terms univalve, 
or consisting of a single piece ; bivalve, or composed of two 
pieces; and multivalve, or composed of more than two. 
For an example of univalve, take a common whelk ; for a 
bivalve, take a muscle or a scallop ; and for a multivalve, the 
barnacle, or balanus, found adhering to the common oyster. 

But although this arrangement may appear at first sight 
perfectly easy and plain, some explanation will be necessary in 
order to guard the student against understanding the above ex- 
pressions in their strictest sense, without qualification. Thus the 



10 INTRODUCTION. 

univalves are said to consist of a single piece, or spiral cone; 
but it would be more correct to speak of this piece as forming 
either the whole or the principal part of the shell : for there is in 
many instances, a much smaller flattened piece attached to the 
foot of the animal, which being drawn in when it retires, closes 
the aperture as with a kind of door, to which in fact the word 
valve might be very properly applied ; it is called however the 
operculum, and the little horny plate, frequently drawn out 
by means of a pin from the aperture of a periwinkle, will 
present a familiar example. 

The same may be said respecting the bivalves; for besides 
the principal portions or valves of which the shell is composed, 
there are in many species, one or two smaller separate portions, 
named " accessary plates' by some authors. They are fixed 
by means of cartilages, on 
the back of the hinge. — j\ 




The engraving, fig. 7, 
represents the accessary 
valves of a species of Pholas, Accessary valves of a Pholas. 

which was on this account arranged by Linnaeus with the Mul- 
tivalves. Nearly allied to the Pholades is a set of shells to 
which De Blainville has given the name " Tubicolce" or inha- 
bitants of tubes. In this case, the bivalve shell is connected 
with a testaceous tube or pipe, to which it is attached either 
by one or by both valves, or in which it lies attached only by 
the cartilages of the animal. In the genus Aspergillum, the 
two small valves are soldered into the sides of the tube in such 
a manner as to constitute a part of it. One of these shells, 
called the Water-spout, might be taken up by a person not 
aware of its real nature, and regarded as a pipe or tube prettily 
fringed, and nothing more ; but upon a closer examination, he 
would find the two valves, the points of which are visible from 
the outside of the tube. 



INTRODUCTION. 11 

HABITS — Land, Fresh-water, or Marine Shells. 

Another distinction, leading to important results in classifi- 
cation, is that which is derived from the nature of the element 
breathed by the Mollusc. And although this consideration 
belongs more especially to the study of the animal itself, yet 
the habits of the animal materially influence the structure of 
the shell. 

The Terrestrial or Land Molluscs live on land, breathe 
air, and feed on plants and trees. — Those who find pleasure 
in horticultural pursuits will at once call to mind a too familiar 
example of these Molluscs in the common garden snail. The 
Land-shells are all univalves, and constitute a family in the 
Lamarckian system under the name " Colimacea" or snails, 
corresponding with the Linnean genus Helix. — They are 
generally light in structure and simple in form. 

The Aquatic, or Fresh-water Molluscs, such as the 
Planorbis, commonly called the Fresh- water Snail; the Unio — 
known by the name of Fresh- water Muscle, is found in 
ponds, ditches and rivers. The epidermis of these is gene- 
rally of a thick, close-grained character, and they are subject 
to corrosion near the umbones. There are but few genera of 
fresh-water shells besides the Uniones, among bivalves, and 
the "Melaniana" among univalves. Concerning the former it 
may be observed, that they are all pearly within, and the colour 
of the thick horny coating embraces all the varieties of brownish 
and yellowish green. 

The Marine, or sea-shells, belong to all the classes and 
orders, and include by far the greater number of species. 
They vary in the habits of the animal, and consequently in 
the situations in which they are found. Some are found buried 
in sand and marine mud, and are named " Arenicolce" or in- 
habitants of sand ; others in holes of rocks and other hard sub- 



12 INTRODUCTION, 

stances, then they are named " Petricolce" — some of these 
latter form the holes in which they live by corroding or eating 
away the stone. A section of these form the family of " Li- 
thophagidce," or stone-eaters, of Lamarck. Others, again, take 
up their parasitical abode in the bodies of animals, and feed 
upon their substance ; as for instance, the Stylifer, which is 
found in the vital part of star-fish, and Coronula, and Tubici- 
nella, found buried in the skin of the whale. 

LOCOMOTION— Attached, Unattached. 

A much more subordinate source of distinction arises from 
the freedom or attachment of the shells. Some of them float 
or walk freely in their natural element; others are fixed or 
attached to foreign bodies. Among those which are attached, 
there is again a difference as to the mode of attachment. Some 
are united to foreign bodies by means of a glutinating sub- 
stance, secreted by the animal, and joining part of the surface 
of the shell to that of the stone, coral, or other substance. In 
this way shells are fixed to each other in groups ; this is the case 
with the Spondyli among bivalves, and the Serpula? among 
univalves. M. de Blainville applies the term i( Fixce" to these 
shells. Others are kept in a particular place by means of a 
Byssus or Tendinous fibrous line or bunch of silky hairs, 
acting as a cable, and allowing the Mollusc to ride as it were 
at anchor. This Tendon is connected with some part of the 
animal from which it passes through an opening or hiatus in 
the shell, as in the Terebratula and the Mytilus. 





INTRODUCTION, 



13 



In the former, represented by the cut, fig. 8, the tendon 
passes through a perforation in the upper valve ; and in the 
latter, Mytilus, fig. 9, the byssus passes out between the valves. 

Before proceeding to explain the characters of the different 
groups, according to the modern system of classification, it may 
be desirable to explain the terms by which the different parts 
and characters are described, and to shew the manner in which 
the shells are measured. For this purpose we shall treat of 
the general divisions separately. We begin with 



UNIVALVE SHELLS. 

In considering Univalves merely with reference to their 
mathematical construction, the first point demanding our 
attention is, whether they are symmetrical or non-symmetrical, 
or, in other words, whether a straight line drawn through the 
shell would divide it into two equal parts. The greater part 
of univalves are non-symmetrical, being rolled obliquely on 
the axis ; but many are symmetrical, being rolled horizontally on 
the axis. The Nautilus presents an illustration of the latter ; 
the Snail is a familiar example of the former. 

Symmetrical Univalves, 

In describing these it will be well to commence with the 
most simple form, such as the Patella, — taking a conical 
species as an example. In this it will be observed that there 




14 INTRODUCTION. 

is no winding or curvature, but a simple depressed cone, and 
that the line a, p, divides it into two equal parts. 

The anterior, a, (cut, fig. 10) is known by the interruption 
of the muscular impression which surrounds the central disc 
(d.) This interruption of the muscular impression is in the 
place where the head of the animal lies in the shell. The im- 
pression itself is caused by the fibrous muscle which attaches 
the animal to the shell. The apex (a) in Patella, gene- 
rally leans towards the anterior (a) part of the shell, and away 
from the posterior (p); and this circumstance has caused some 
mistakes, because in Emarginula the apex leans towards the 
posterior; and students, instead of examining the muscular 
impression, which is the only criterion, have only noticed the 
direction in which the apex turned, and concluded that to be the 
anterior, towards which it inclined. The lines or ribs running 
from the base to the apex of the shell, in the direction r, are 
called radiating lines ; and those which encircle the cone in the 
direction c c, from front to back, are very properly described 
as concentric. The length is measured from front to back in 
the line e ; the breadth, from side to side, in the line b ; and 
the depth from the apex to the base. 

Let it be observed that patelliform, or limpet- shaped shells 
are not all symmetrical; Umbrella, Siphonaria, Ancylus, &c. 
will form exceptions, of which we have yet to speak. And the 
learner may also be reminded that the Limpets themselves are 
not all regular in their form : for as they adhere to rocks and 
other rough surfaces, and are so little locomotive, in many in- 
stances they partake of the inequalities of the surface, and 
conform to its irregularities. This adherence is not effected by 
any agglutinating power in the animal, nor by any tendinous 
process like that described above; but simply by means of the 
foot of the animal acting as a sucker. 

The next variation in symmetrical univalves is to be ob- 



INTRODUCTION. 15 

served in the tubular, curved form, the example of which will 
be the Dentalium, fig. 12. 




72 

Dentalium Elephanthmm. 
This has an opening at the anterior termination a, called the 
aperture. The opening at the posterior end (p) is named a 
fissure, or perforation. The ribs running along the sides of 
the shell are longitudinal, or radiating. And the lines round 
the circumference are lines of growth, or concentric — each one 
having in succession, at earlier stages of growth, formed the 
aperture. They are described as concentric, or transverse. 

Symmetrical Convolute Univalves. 

The Nautilus, the Spirula, the Scaphite, and the Ammonite 
are the leading types of this form ; but when we use the term 
symmetrical, in reference to these, the word must not be un- 
derstood in its strictest sense, for no shell is perfectly symme- 
trical : but it means that there is no perceptible difference in 
the proportion of the two sides ; as in the human body, the 
right side is larger and more powerful than the left, yet to a 
degree so small that it gives no apparent bias to the figure . 

CHAMBERED SHELLS. 

Many of the shells now under consideration are chambered, 
that is, the internal cavity is divided into separate compart- 
ments by plates reaching across it, named Septa ; and the only 
connection between the chambers is formed by the small pipes 
passing through them,to which the name of Siphon is attached. 



16 



INTRODUCTION, 



Septa, 

The septa are simple in some species, as in the Nautilus, 
fig. 13. In others they are undulated, having waved edges, as 
in some species of Ammonites ; in others they are angulated, 
as in Goniatites, fig. 480 in the plates ; and in the greater 
number of instances, among the Ammonites, they are arbores- 
cent, or branched. 




Vi - 74 IS 

13. Section of Nautilus.— 14. Undulating Septa.— 15. Arborescent Septa. 

In the above section of a Nautilus, fig. 13, diminished in 
size, showing the whorls and chambers (c), it will be seen that 
the edges of the septa (s) are formed in one simple curve. In 
fig. 14, the upper part of an Ammonite, the undulating line 
will be seen ; and in fig. 15 a specimen is given of the arbo* 
rescent septa. 



Siphon. 

The Siphon is dorsal when placed near the outside of the 
whorls ; central when near the middle ; and ventral when near 
the inside of the whorl, or that part which leans against the 
last volution. When it passes uninterruptedly from one 
chamber to another, it is described as continuous, as in the 
case of Spirula ; when, on the other hand, it only passes 
through the septum a little distance, and opens into the 
chamber, as in Nautilus, it is discontinuous. 



INTRODUCTION. 17 

Whorls of Symmetrical Univalves. 

They are disunited when they do not touch each other, as in 
the case of Spirula (fig. 47 1 in the plates) ; but in the con- 
trary case they are said to be contiguous. In some species of 
Nautilus the whorls overwrap each other in such a manner 
that the early whorls are entirely covered by the last, the 
edges of which reach to the centre of the disk : the spire is 
then said to be hidden ; as in the Nautilus Pompilius. In 
Nautilus umbilicatus the spire is nearly hidden, the whorls 
not quite covering each other ; but in the greater number of 
the Ammonites, the largest part of the preceding whorls is 
seen. To express the degree in which the whorls overwrap 
each other, has caused much difficulty in concise descriptions. 
Perhaps it would be well to apply the term spiral disc to so 
much of the shell as is seen besides the last whorl, and to 
describe it as large or small in diameter, compared with the 
whole : or to say that the whorls of the spire are half, or one- 
third, or one-fourth covered, as the case may be. 

Aperture of Symmetrical Univalves. 

In Ammonites Blagdeni and some others the aperture is of 
an oblong square ; it is then said to be sub-quadrated ; in Nau- 
tilus triangularis it is angulated ; in Ammonites Greenoughi 
it is of an interrupted oval shape, described as elliptical. In 
the greater number of Orthocerata, it is rounded or circular. 
The entrance of the last whorl into the aperture of some 
rounded species of Nautilus causes it to take a semi-lunar 
form ; if rounded at the sides it is said to be reniform or 
kidney-shaped: if pointed at the sides it is semi-lunar; and 
in some species of Ammonites, it is five-sided or quinque- 
lateral. 



18 



INTRODUCTION. 

Measurement of Symmetrical Conical Univalves. 




e?efr7i 



The width is measured across the aperture, which is the 
widest part of the shell. The length (I) from the dorsal part 
(d) of the aperture to the dorsal part of the whorl (d) on the 
opposite part of the shell. The ventral part of the whorls is 
that nearest to the axis, and the dorsal that which forms the 
outline of the figure. 

NON-SYMMETRICAL UNIVALVES. 

These are conical } irregular, spiral, or convolute. The 
conical form is when there is no enrolment of the apex. 
Although the Patellae were described as symmetrical, there are 
several species of Patelliform shells which are not symmetrical. 
In Umbrella, for instance, the apex is oblique, the shells being 
placed obliquely on the animal. In the genus Siphonaria, 
there is a groove on one side, where the brachia or gills of the 
animal rest. In the genus Ancylus, it will be observed that 
the apex bends on one side, and the animal is like the Limnsea, 
which has a spiral shell. The cup and saucer Limpets, or 
Calyptrsedae, present a group which requires to be described, 
differently from the symmetrical or true Limpets. Their 
structure is very curious, and they vary considerably among 



INTRODUCTION. 



19 



themselves, some of them being simply conical, others nearly 
flat, or discoidal, and others more or less spiral. But their 
principal peculiarity consists in their having a small internal 
process or plate variously shaped, commonly named their 
septum. 

Septa of Limpets. 

The septa of Limpets assume a variety of forms, the prin- 
cipal of which will be seen in the accompanying engravings. 




The form from which the group derives its generic appella- 
tion is that of the cup-shaped or Cyathiform species (fig. 17). 
In the Crepidulse, or Slipper-Limpets, the septum is flat, 
reaching across the opening, like the deck of a vessel ; it is 
then described as transverse (fig. 20). In Calyptrsea Eques- 
tris, it has two prominent points, and is described as bi-fur- 
cated (fig. 18). In another species, it is a three-sided plate 
rather spiral at the apex (fig. 19). 

Measurement of Cup and Saucer Limpets. 




M5r^ 



The line marked a, p, 1 1, indicates the direction in which 

c 2 



20 



INTRODUCTION. 



the shell is to be measured for length, a indicates the ante- 
rior, p the posterior. The line d (fig. 23), from the apex to 
the base, is the depth. The line b (fig. 28), is in the direc- 
tion of the breadth. 

Irregular nonsymmetrical Univalves. 

Serpuliform shells are irregularly twisted (tortuous) hollow 
tubes, which were formerly considered to have been secreted 
by a kind of worm, but now known to be the shells of true 
Molluscs, of a kind not very widely differing from those which 
have regularly spiral shells. The greater part of these are 
attached to foreign bodies, or to each other in groups. Some 
are attached by the whole length of the shell, they are then 
said to be decumbent. Some of these are coiled round like 
the Spirorbis, the little white shell seen on the carapace of the 
Lobster or on leaves of sea-weeds; they are then said to be 
discoidal ; others again, such as the Vermetus, approach more 
nearly to the spiral form. The deviation from the regular 
spire only taking place after the few first volutions. 

SPIRAL NON-SYMMETRICAL UNIVALVES. 

As these constitute the largest 
class, it will be necessary to dwell 
upon them in detail. First as to 
measurement. 

The length is measured from the 
apex, to that part of the aperture a 
-I (fig. 24), at the greatest distance 
from it. The breadth is in the oppo- 
site direction. The anterior ; or 
front part of the aperture, is marked 
a, where the head of the animal pro- 
trudes. 




INTRODUCTION. 



21 



Spire of non-symmetrical Univalves. 
In counting the whorls of which the spire consists, we com- 
mence at the apex, and reckon downwards to the last, or body 
whorl. The spire is described as being long or short in rela- 
tion to the aperture : in which case, all that is above the aper- 
ture is measured with the spire. Its apex requires particular 
notice, as the character of the whole shell frequently depends 
upon the particulars observable in this part. It is sometimes 
obtuse, or blunt ; sometimes acute, or sharp. In the Cones it 
is frequently flat, and in Planorbis it is concave. It is some- 
times of a different structure from the rest of the shell, retain- 
ing the horny and transparent appearance which characterized 
it when the animal was first hatched. The Tritons present 
an instance of this, although it is not always observable, owing 
to the tenderness of the substances which causes it to break or 
fall away in many specimens. A very remarkable instance 
also occurs in Bulinus decollatus (cut, fig, 27, 28), so named, 
because the apex, to the depth of several whorls, falls off, and 
the shell is decollated. In this, and many more instances, 
among Pupseform land shells, the occurrence of this circum- 
stance seems to be by no means rare or accidental, a provision 
having been made for filling up the opening by a septum. A 




Fig. 25, obtuse; 26, acute ; 27,28, decollated; 29, concave; 30,papil- 
31, mammellated ; 32, discoidal. 



22 



INTRODUCTION. 



papillary apex is one which is swelled at the extremity into a 
little rounded nob, or nipple ; and a mammellated apex is one 
which is rounded out more fully into the shape of a teat. 

Whorls. 
The spire is described as consisting of numerous or few 
whorls, and sometimes the number of them is particularly 
stated. A whorl consists of one turn of the spiral cone. The 
whorls are described as flattened, when the sides are not 
bulged out so as to cause the outline of the spire to deviate 
considerably from straightness : when the contrary is the case, 
the whorls are said to be ventricose, and either rounded or 
angulated. The degree of rapidity with which the whorls 
become enlarged presents an important source of distinc- 
tion. The suture, or seam, which separates one whorl from 
another is also noticed as being distinct or otherwise ; 
canaliculated, or grooved ; or covered by an enamel, which in 
some instances is swelled into a ridge or tumid. 




Fig. 33,/eto; 34, numerous; 35, rounded, ventricose ; 36, angular, v en- 
tricose ; 37, flattened. 

Suture. 





Fig. 38, canaliculated ; 39, enamelled. 



INTRODUCTION. 



23 



Varices. 
Varices are caused by periodical rests or stoppages in the 
growth of the shell, when the edge of the aperture thickens, 
and renders the shell as complete as when full grown. Again, 
after an interval, another check takes place, and another 
thickened edge is formed, and so on in succession, until 
the animal arrives at maturity, and the shell is full-grown. 
The thickened edges successively forming the aperture, 
remain visible on the outside, through all the subsequent 
stages. When these rests take place at frequent periods, the 
varices will of course be numerous as in Harpa and Scalaria. 
They occur at regular or irregular distances, varying in shape 
and other characters. When the varices occur at regular 
intervals, and form a connected ridge from whorl to whorl up 
the spire, they are said to be continuous, as in Ranella ; when 
on the contrary, the varix on one whorl does not come in con- 
tact with that on the other, they are described as discontinuous. 
In order to distinguish a regular varix from a mere external 
ridge, it will be sufficient to notice whether its edge overlaps 
the external surface, and whether it resembles the open edge 
of the aperture, which true varices do. 





Fig. 40, numerous ; 41, few, continuous ; 42, few, discontinuous. 

Aperture. 
The aperture or opening of the spiral tube, was formerly 
described as the mouth ; a term calculated to convey an 



24 INTRODUCTION. 

erroneous impression, when applied to a part of the shell which 
has no correspondence with the mouth of the animal. The 
word aperture is used by modern writers in a general sense, 
including the cavity, its edge, and the canals. The cavity 
itself is distinguished in various shells as to its shape, which 
depends much upon the degree of modification produced by 
the last whorl. In some cases, as in Cyclostoma, where the 
aperture stands apart from the last whorl, the shape is round, 
or nearly so. The Scalaria presents a good example of this. 
In others, where the inner edge or lip, wrapping over the 
body whorl is nearly straight, the aperture is semi-lunar, or 
half-moon shaped : this is remarkable in the " Neritacea* of 
Lamarck, named, on that account, " hemi-cyclostomata" by 
De Blainville. In a great number of instances, the lower 
part of the body whorl enters obliquely into the upper part of 
the aperture, the result being a pyriform, or pear-shaped open- 
ing. The aperture is described as long when it is largest in 
the direction of the axis, and wide, in the contrary case. The 
anterior is the part at the greatest distance from the apex, 
and the body whorl ; the posterior, the part nearest to the apex. 
Thus some apertures are described as posteriorly contracted 
and anteriorly widened, or the reverse. A linear aperture is 
one contracted in its whole length, as in Cyprsea. When the 
whorls are angulated, a trigonal aperture is the result, as in 
many species of Trochus. Some are transversely oval, that is 
in an opposite direction to the axis, and others longitudinally 
oval. When the whorls are formed with two outer angles, a 
somewhat quadrated aperture is formed. There are other 
variations too numerous to mention. 



INTRODUCTION. 



25 



Apertures. 




Fig. 43, Heliciua, semilunar ; 44, Pirena, piriform ; 45, Cyprsea, linear; 
46, Trochus, trigonal; 47, Cyclostoma, rounded; 48, Chilina, poste- 
riorly contracted ; 49, Stomatia, transversely oval; 50, Murex, longitu- 
dinally oval. 

The entire edge of the aperture described generally, is 
named the Peritreme, but this term can only be conveniently 
applied in cases where, in some at least of its characters, it is 
the same all round, so that one descriptive term is applicable 
to the whole. As, however, this is of rare occurrence, it is 
found convenient in descriptions to separate the rim from the 
outer lip. In a great number of instances, this is done natu- 
rally, by a canal, or notch at the anterior or lower extremity, 
and by the posterior union of that part which overlays the 
body whorl with the other portion. At these two points the 
outer and inner lips separate from each other : we therefore 
describe the 



Canals of the Aperture. 

When there is neither notch nor canal, anteriorly or poste- 
riorly, interrupting the edge of the aperture, it is described 
as entire. When there is a notch or sinus at the anterior 



26 



INTRODUCTION 



extremity, it is said to be emarginated. When the edge of 
this notch is expanded, and drawn out in the form of a beak, 
it is said to be canaliferous, or to have a canal. When, in 
addition to this, the lips are thickened and contracted poste- 
riorly near their junction, and drawn out so as to form a 
groove, it is said to be bi-canaliculated, or to have two canals. 
The anterior canal is said to be long or short, according 
to the proportion which it may bear to the rest of the shell. 
Thus the canal of Ranella ranina (fig. 393 in the plates), may 
be described as short; while that of Murex haustellum, 
(fig. 396, pi.) is long. When it is wide near the aperture, and 
becomes gradually contracted towards its termination, it is said 
to be tapering, as in Pyrula (fig. 388, pi.) ; when the termi- 
nation is sudden, it is described as truncated. If, on placing 
the shell upon a plane, with the aperture downwards, the canal 
is seen to rise upwards, it is recurved. In Buccinum and 
Nassa it is turned suddenly over the back, and forms a short, 
curved elevation ; it is then described as recurved and vari- 
cose. If the edges meet, so as to form a tube, it is said to be 
closed, as in some species of Murex and Typhis. The pos- 
terior canal is, in some cases, free, or standing out from the 
spire, as in some species of Ranellse; while in others it is 
decumbent, running up the sides of the spire, as in Rostellaria 

(fig. 402, pi.) . 

Canals. 




Fig. 51, Fasciolaria, truncated ; 52, Nassa, recurved, varicose ; 
53, Cerithium, recurved ; 54, Typhis, closed. 



INTRODUCTION. 27 

Lips, or edges of the Aperture. 

The part of the edge of the aperture next to the body whorl 
is named the inner, or columellar lip. Posteriorly it com- 
mences at the point of union with the outer lip, where that 
touches the body whorl, the junction being generally marked 
by an angle, and sometimes by a canal. Anteriorly it 
terminates where there is generally seen a notch or canal, 
or sudden angle, from which the outer lip proceeds. The part 
which setting out from the body whorl, and proceeds outwards 
at a distance from the axis, till it reaches the anterior canal or 
notch (or its place in case of absence) is named the outer lip. 
In many cases the edges are united in such a manner, that it 
is difficult to distinguish where the inner lip terminates, and 
the outer lip commences : when this is the case, it is usual to 
describe the margin or peritreme, as a whole, without distin- 
guishing the parts. The outer lip, sometimes called the right 
lip, or labrum of continental writers, is sometimes acute, not 
being of thicker substance than the remainder of the shelL 
In other cases it is obtuse, or thickened and rounded at the 
edge. When thickened and turned backwards it is described 
as reflected ; when, on the other hand, it is turned inwards 
towards the axis, as in the Cyprsedae, it is inflected, or invo- 
lute. When it is toothed, a distinction must be observed as 
to whether the dentations are external or internal. If the 
teeth are small and numerous, it is denticulated; if larger, it 
is dentated ; when expanded into a kind of wing, as in some 
species of Strombus and Rostellaria, it is described as alated ,- 
and a family in Lamarck's system is named " Alatee," from 
this very circumstance. In some of those which are expanded, 
the expansion is divided into separate, attenuated portions, 
they are then said to be digitated. 



28 



INTRODUCTION. 



Outer Lips. 




Fig. 25, Helix, reflected; 56, Cyprsea, involute, denticulated; 57, SerapLs, 
alated ; 58, Murex, digitated ; 59, Rostetlaria, dentaied. 



The inner lip, sometimes named the columellar lip, or 
" labium" is subject to similar variations as to thickness, 
dentition, &c. That portion of it which lies upon the body- 
whorl is frequently distinguished from that which intervenes 
between it and the notch or canal. De Blainville, restricting 
the term lip " bord gauche" to the former portion, applies the 
term i( columella" to the latter; and in some instances this 
may be the more convenient method of describing the part in 
question. The columellar lip is sometimes detached entirely 
from the body of the shell, as in Murex haustellum ; in others 
it is decumbent, or lying over the last whorl, although quite 
distinct, and in some cases, thickened, callous, or tumid. 

At the lower or anterior part, sometimes called the columella, 
there are in many instances flattened, laminated folds ; these 
are particularly conspicuous in the genera Cymba and Melo, 
where, being obliquely spiral and laminar, they are extremely 
elegant, presenting to the eye graduated repetitions of the line 
of beauty. In other cases, as in the Turbinellee, they are 
more horizontal and thickened. 



INTRODUCTION. 



29 



In some cases the columella is swelled into a varicose mass ; 
as in Oliva, Ancillaria, &c. ; it is then described as tumid or 
varicose. It is sometimes tortuous, and sometimes straight, 
and is susceptible of many variations, too minute and par- 
ticular to be described in this part of the work. 

Columellar Lips. 





Fig. 60, Melo, obliquely plaited; 61, Turbinellus, horizon- 
tally plaited ; 62, Ancillaria, varicose, tortuous; 63, Na- 
tica, straight. 



OPERCULUM. 

The aperture of many species of shells remains constantly 
open ; but in a great number of species it is occasionally closed, 
whenever the animal is retracted within the shell, by a calca- 
reous or horny piece called the operculum. This must be dis- 
tinguished in the first instance from another kind of calcareous 
covering, which in some univalve shells serves to close the aper- 
ture during a certain portion of the year. This piece, named the 
epiphragm, although hardened and shelly in appearance, is no 
real part of the animal or of the shell ; being only a secretion 
temporarily hardened, for the purpose of defending the animal 
from external influences during the hibernating or torpid 
season, to be dissolved when that season is at an end. On 
examining this piece, it will be observed that it is not formed 



30 INTRODUCTION. 

in regular layers like the rest of the shell; while the true 
operculum is of a regularly laminated structure, having a 
nucleus and receiving obliquely deposited additions, either in 
a lateral spiral or concentric direction. It is attached to the 
posterior part of the foot on the upper surface ; and when 
the animal retires within its shell, that part of the foot enters 
last, drawing the operculum after it, and thus closing the 
aperture. 

The opercula of various shells differ in the first place as to 
their chemical composition. They are calcareous when formed 
principally of calcareous matter, like the rest of the shell, as 
in Neritina, Nerita, and some others. They are corneo- 
calcareous, when upon an internal lamina of horny consistency 
there is a thickened layer of shelly matter. This is the case 
with shells of the genus Turbo and Phasianella, which are on 
this account distinguished from those of the genus Trochus ; 
the opercula of the latter being horny or corneus. 

The size of the operculum is distinguished by comparison 
with the rest of the shell ; thus, those of Strombus, Cassis, &c. 
are small ; while those of Cyclostoma and others are large, 
filling up the cavity at its outer edge. 

The direction in which the successive layers are deposited, 
forms another ground of distinction. The disc is formed in 
some instances of a series of whorls, the apex or nucleus being 
more or less central ; if these whorls are numerous, the oper- 
culum is described as multispiral, as in shells of the genus 
Trochus ; if few, as in Cyclostoma, it is paucispiral. In 
some instances the flattened spire consists of but one whorl, 
it is then unispiral; and when scarcely one turn is completed, 
it is described as subspiral. When the layers are applied 
upon each other in such a manner that the nucleus is central, 
and the edges of the subsequent layers are extended beyond 



INTRODUCTION. 



31 



each other all around, so as to form rims, the operculum is 
described as concentric; if the nucleus is lateral, or at one 
side without being spiral, it is lammellated ; and when it forms 
a terminal point, enlarging in the form of a finger-nail or 
claw, it is unguiculated. In the operculum of a Neritina, 
there is a lateral process, by means of which it is locked into 
the columella, the term articulated is then applied* In that 
of Navicella, there is also a process which appears to radiate 
from the nucleus, it has therefore been described as a radiated 
operculum. 

Opercula of Spiral Univalves. 




Fig. 64, multispiral ; 65, paucispiral; 66, concentric; 67, articu- 
lated; 68, radiated ; 69, lammellated; 70, unguiculated. 



BIVALVE SHELLS. 

Bivalve shells, named Conchacea by Lamarck, are those 
which consist of two principal portions united to and folded 
upon each other by means of a hinge. The pieces united 
compose the shell, while each piece separately is called a valve. 
Considering the bivalve shell as a whole, it will be necessary, 



32 



INTRODUCTION. 



in the first instance, to describe the position in which it is to 
be observed, in order to give the student a clearly defined 
notion of what is intended, when terms expressive of height, 
depth, length, breadth, &c. are used, as well as when the 
anterior and posterior extremities are spoken of. For this 
purpose, we must suppose the animal to be living and creeping 
along the bed of the sea by means of its foot ; where this foot 
protrudes, will be the ventral margin, and the opposite part 
the dorsal margin of the shell. There will then be a valve on 
each side ; and if we further suppose the animal to be walking 
forward with its back to the observer, the right and left valves 
will correspond with his right and left sides. 

Measurements. 




*a£ 7^3 



The length will be measured from anterior (a) to 'poste- 
rior (jo), and the lines of growth running in the same direction 
will consequently be longitudinal or concentric ; transverse of 
some authors. The height will be from the umbones (u), to 
the ventral margin, and lines or bands in that direction are 
termed radiating ; longitudinal, according to some authors. 



INTRODUCTION. 33 

The points from which the growth of the shell commences, 
are called the umbones ; these usually turn towards the anterior 
part of the shell : if this circumstance fails to point out the 
anterior, it may in many cases be distinguished by the mus- 
cular impressions of the mantle. If this has a sinus or winding, 
it is always near the posterior muscular impression ; and in 
all cases where there is an external ligament, it is on the pos- 
terior side. 

There is sometimes an impression near the front of the 
umbones, which forms a semicircle on each valve ; the space 
within this semicircle is called the lunule (wood-cut, fig. 71 
and 72, I. I. I.) ; a corresponding depression, when it exists 
on the posterior margin near the umbones, is named the 
escutcheon. 

Hinge. 




Fig. 73, I t, lateral teeth ; c t, cardinal teeth; c, cartilage under 
the ligament ; I, ligament ; /. fulcrum of the ligament. 

The hinge of the shell is on the dorsal margin, and is com- 
posed of the various apparatus by which the two valves act 
upon each other in opening and shutting It consists of a 
ligament , which is placed on the dorsal margin, just at the 
back of the umbones, and unites the two valves together ; the 
cartilage or thick gristly elastic substance, sometimes found 
close to the ligament, to which it then forms an inner coating, 
and sometimes received into a pit within the shell. It serves 
the purpose of keeping the shell open when not forcibly closed 
by the adductor muscles. An inner layer of shelly matter upon 

D 



34 INTRODUCTION. 

which are placed teeth, and pits to receive them on the two 
valves reciprocally. Each of these it will be necessary to treat 
of more at large ; observing, at the same time, that in some 
species of Bivalves these parts may be wholly or partially 
wanting. Thus we meet with some shells, such as the Muscle, 
without teeth ; and there is the group containing Pholas, &c. 
the hinge of which is destitute of teeth and ligament, the two 
valves being kept together by loose cartilages, and by the con- 
tracted space in which they are confined. 

Ligament and Ligamentary Cartilage of the Hinge. 

These two distinct substances have been described by many 
writers as though, composing the same mass, they were of one 
substance ; but the difference may very easily be explained. 
The true ligament is external, being fixed on the edge of one 
valve behind the umbones, and passing over in an arch to the 
corresponding edge of the other, very correctly retaining the 
name of ligament, because it serves the purpose of binding 
the two together. The thick, elastic substance, which Mr. 
Gray names the cartilage, is sometimes found in connexion 
with the ligament, so as to form one mass with it, although it 
is always separable and placed within it : it is sometimes 
placed quite within the shell, and separated from the ligament, 
in a pit or hollow formed for its reception in the hinge lamina, 
near the centre. It is found in both valves, and being elastic, 
the portion in one valve presses against that in the other, so 
as to keep the valves apart, unless voluntarily closed by the 
adductor muscles of the animal. The ligament is sometimes 
spread over an external area, as in Area, while the cartilage is 
placed in several grooves of the same area, beneath the outer 
covering. 



INTRODUCTION. 35 

Hinge lamina, Teeth and Fulcrum of the Ligament. 

In a great variety of cases, there is a thickening of the sub- 
stance of the shell within, under the dorsal margin; this is 
named the hinge lamina. It is sometimes merely callous ; 
but in many cases it has raised teeth in both valves, those in 
one valve entering into corresponding cavities in the other. 
Those which are placed immediately below the umbones, and 
seem to take their rise from beneath them, are called cardinal 
teeth ; those at a distance from the umbones, which are seen 
to lie along the upper margin of the shell are named lateral 
teeth . 

When the cardinal teeth terminate in a double point, which 
is not unfrequently the case, they are said to be bifid. The 
lateral teeth, in various species, are distinguished as termi- 
nating near to, or at a distance from the umbones. In the 
Nuculae and Arcse there is a row of teeth placed across the 
hinge lamina. In which case, the lateral cannot be distin- 
guished from the cardinal teeth. 

Muscular Impression. 




Fig. 74. a, anterior ; p, posterior ; m i, muscular impressions. 

Lamarck divides the Bivalve shells into two general orders ; 

d2 



36 INTRODUCTION. 

the first is named " Dimyaria," having two adductor muscles ; 
and the second, " Monomyaria," having but one. These 
adductor muscles are used for the purpose of drawing the 
valves together, being composed of contractile fibrous gristle, 
fastened firmly to the inner surface of each valve. The place 
where they are thus fixed may be seen when the animal is 
removed, by depressed areas, which are generally pretty well 
defined, and are named muscular impressions. Where there 
is but one adductor muscle, there will be but one of these im- 
pressions near the centre of each valve, but in the Dimyaria, 
where there are two, the impressions are seen, one on the ante- 
rior, and one on the posterior of each valve, just below the 
hinge lamina. They are sometimes complex, that is composed 
of several portions in a group; but in general, they are simple 
and well defined. 

They are also described as large or small, in proportion 
to the size of the shell ; regular or irregular in form. The 
animal is attached to the inner surface by the fibrous 
portions of the mantle, which creates a linear impression 
or cicatrix, commonly described as the palleal impression, or 
muscular impression of the mantle. It runs near the ven- 
tral margin from one muscular impression to the other, some- 
times in a smooth continuous line or band, and sometimes in 
an interrupted series of small impressions. Near the point of 
union with the posterior muscular impression, there is some- 
times a more or less considerable winding inwards towards the 
centre of the shell, and back again towards the point of union. 
This is named the sinus, and is distinguished as being angular 
or rounded, large or small, according to the species. When 
it enters towards the centre of the shell in a tongue-shaped 
outline it is said to be ligulate. Where it exists it affords a 
certain index to the posterior side of the shell; as it is the 
region through which the excretory tubes pass. 



INTRODUCTION. 



37 



Umbones. 

These are the prominent points of the dorsal edge, where 
the growth of the shell commenced, and are called beaks, by 
some English writers. In some instances they are close to 
each other; in others they are rendered distant from each 
other by the intervention of areas in the hinge, as in Spondyli, 
&c. In Pectunculus they are straight; in Venus curved 
towards the anterior margin ; in Isocardia, spiral ; in Chama, 
decumbent ; in Diceras, free. In shells subject to external 
corrosion, the process commences at the umbones. 




Fig. 75, distant ; 76, straight ; 77, curved; 78, spiral; 79, decumbent ; 
80, free; 81, close. 

GENERAL CHARACTER OF BIVALVES. 

When the breadth is spoken of, the distance between the 
most convex parts of both valves, when closed, is intended ; 
but when an expression implying thickness is used, it refers to 
the substance of each valve : it is important to bear this in 
mind, as many persons have been misled by descriptions in 
which the distinction has not been attended to. Glycimeris 
(fig. 67 in the plates) is a thick shell, but Anatina (fig. 69 in 
the plates) is a broad one. 



38 INTRODUCTION. 

Regularity . 

A great number of Bivalves are extremely regular in their 
form. These are generally locomotive, and consequently free 
from those obstructions in growth occurring to stationary shells, 
which being confined in a particular position, or to a parti- 
cular spot, modify their shape according to the substance with 
which they come in contact, and thus become irregular. This 
is generally the case with shells which are attached to sub- 
marine substances, such as Spondyli, Oysters, &c. ; and 
the degree of irregularity will depend upon the extent of 
surface involved in the attachment. In the case of fixed 
shells, the attached valve is usually termed the under valve, 
and the other which moves freely upon the hinge, is termed 
the upper valve. 

Form and Proportions. 

Bivalves are said to be equivalve when the two valves cor- 
respond in extent, breadth, and thickness ; and of course 
inequivalve in the contrary case. They are equilateral when 
a line drawn from the umbones to the ventral margin would 
divide the shell into two nearly equal parts ; and of course 
inequilateral in the opposite case, which occurs in the great 
majority of instances. 

A Bivalve is said to be compressed, when the distance is 
small from the most prominent part of one valve to that of the 
other. It is cylindrical when lengthened, and more or less 
rounded in its breadth, as in Lithodomus (fig. 161 in the 
plates). It is cordiform when the shape presents a resem- 
blance to an imaginary heart, as in Cardium cardissa (fig. 122 
in the plates), and in the Isocardia (fig. 126 in the plates). It 
is linguiform when it resembles a tongue in shape, as in 
Vulsella (fig. 185 in the plates) ; rostrated when it protrudes 



INTRODUCTION. 39 

at either extremity, and terminates in a kind of point, as in 
Sanguinolaria Diphos (fig 99 in the plates) ; truncated when 
it ends in a square or angle, as if cut off; an example of 
which may be seen in Solen (fig. 60 in the plates). 

Other Bivalves are distinguished as being auriculated, 
having processes flattened and expanded on either side of the 
umbones, as in Pecten (cut, fig. 82). When there is one of 
these on each side of the umbones, it is bi-auriculated ; when 
only on one side, it is uni- auriculated. When the expansion 
is very broad, as in Unio alatus (fig. 142 in the plates), and 
in the Hammer Oyster (cut. fig, 83), the term alated is used. 




Fig. 82, auriculated ; 83, auriculated, alated. 

With regard to these alated species of Uniones, it is neces- 
sary to observe that they are also " adnate? as it is termed ; 
the two valves being joined to each other by the dorsal edge 
of the expanded parts, and united so completely in substance 
with each other, that they cannot be separated without being 
broken. Many other terms are used to express difference in 
Bivalves, but being generally applicable to Univalves and 
Multivalves, as well as to them, they will be found explained 
at large in the alphabetical part of the work. 

MULTIVALVE SHELLS. 

These are of three different kinds; first, the "dorsal" as 
they are termed by Linnaeus, because they form a ridge in the 
back of the animal. They are composed of eight pieces, or 



40 



INTRODUCTION. 



separate valves, placed in a longitudinal series, being joined to 
each other by inserted lamina, and named Articulata by De 
Blainville, on that account. The genus Chiton is the only 
example of this kind of Multivalves. 




Fig. 84, 85, Chiton. «, anterior ; p, posterior ; d, dorsal ridge ; I U lateral 
areas of the valves ; c c, central areas ; i i, inserted lamina ; m, margin. 

The second kind, M. De Blainville terms the lateral 
bivalves, the pieces being placed in pairs on each side of the 
animal; these compose the " Pedunculated Cirripedes." 




Fig. 86, Anatina. 



They differ considerably in the number and arrangement of 
the valves ; the small ones, which are found near the peduncle 
in some species, are sometimes termed accessary valves ; those 
which form the edge through which the bunch of Cilia pro- 
trude, are termed ventral, and those on the opposite side 
dorsal. The extremity joining the peduncle is the basal, or 
anterior ; and the upper extremity is the apsiral, or posterior. 
The peduncle is the medium of attachment to submarine sub- 
stances, to which this well known tribe of shells adhere. 

The third kind are termed coromdar by De Blainville, and 



INTRODUCTION. 



41 



compose the order Sessile Cirripedes of Lamarck ; they consist 
of a number of valves placed against each other side by side 
in a circle, supported on a plate, or tube, or cup, and closed by 
an operculum composed of two or more valves. 

The basal support is sometimes thick and flat, sometimes 
forming an elongated tube, and sometimes hollowed out into 
a cup. In other species it is altogether wanting. The oper- 
culum always consists of more than one piece, generally of 
two pairs: they are either articulated to each other by serrated 
edges, and placed against each other conically, as in Balanus, 
or they lie flat in two pairs against each other. Through the 
ventral pair the cirrhi protrude. 

The parietal valves, composing the principal part of the 
shell, vary in number, form and position. The anterior valves 
are placed on the same side with the cirrhi; the posterior, 
those on the opposite side ; and those which remain between 
on each side are the lateral valves. In many cases, parti- 
cularly in Balanus, each valve is separated into the prominent 
and depressed areas, and the inserted lamina. In some 
instances, the parietal portion is formed by a single rounded 
piece. 

In the accompanying cut (87), the prominent areas are dis- 




42 INTRODUCTION. 

tinguished by the letters pr, and the depressed areas by r ; 
the posterior valves of the operculum are marked p. o., and 
the anterior a. o. The basal valve (fig. 88) belongs to a 
Balanus. Fig. 89 is an Acasta, the cup-shaped base of which 
is represented at fig. 90 . 

In the foregoing explanations we have omitted many of 
those general terms which, relating to external characters, are 
applicable to shells in almost every division of the system. It 
may be as well, however, to enumerate a few of them in this 
place, although they are explained under their respective 
letters in the alphabetical part of the work. 

When bars or ribs, or large striae are crossed by others 
radiating from the umbones, shells are said to be cancellated, 
as represented in cut, fig. 91. When there is a series of 
nodules or spines on the upper part of the whorls, they are 
coronated, as shewn in cut, fig. 92. When a series of pro- 
jecting parts overlay each other, in the manner of tiles, as in 
the cut, fig. 93, the word imbricated is applied. When marked 
by a regular series of ridges, radiating from the apex, they are 
pectinated ; the species of Chiton, a single valve of which is 
represented in cut, fig. 94, has received the specific name of 
pectinatus, in consequence of this character. Shells are said 
to be plicated when characterized by angular bendings or fold- 
ings in their surface, as shewn in cut, fig. 95. A strong 
instance of this is seen in the Ostraea Crista-Galli. When the 
margin of any shell has a series of minute notches, resembling 
the teeth of a saw, it is said to be serrated; when covered 
with raised points or spines it is aculeated ; and when striated 
in both directions, it is decussated ; when covered with a num- 
ber of raised rounded points, it is granulated ; and having a 
series of these points placed in a row, near or upon the edge, 
it is denticulated, as already explained in reference to the 
outer lips of Spiral Univalves. When the external surface is 



INTRODUCTION. 



43 



rendered uneven by raised knobs, it is said to be tuberculated ; 
and if rendered rough and prickly by sharp points it is muri- 
cated, as in the cut, fig. 97. The term reticulated is applied 
to fine raised lines, crossing each other, and resembling fine 
net- work. 




External surface. Fig. 91, cancellated; 92, coronated; 93, imbricated ; 
94, pectinated; 95, plicated; 96, decussated; 97, muricated ; 
98, foliated. 

By the foregoing general observations and explanations, it 
is trusted that the reader will be prepared for the following 
exposition of the general arrangement of Lamarck, and the 
principles upon which it is founded. 



GENERAL ARRANGEMENT 

ACCORDING TO LAMARCK. 

In Lamarck's " Histoire Naturelle des Animaux sans Ver- 
tebres," he divides the invertebrata into classes, the 9th, 10th, 
and 11th of which include animals possessed of shells properly 
so called. These are the Annelides, the Cirripedes, the 
Conchifera, and the Mollusca. 

The class Annelides constitutes the 9th, and is divided 
into three orders, namely, the " Apodes," " Antennees," and 
" Sedentaires ;" the last of which, Sedentaria, alone contains 
testaceous animals. This order includes tubular shells, which, 



44 INTRODUCTION. 

with the exception of Dentalium, are irregularly twisted, and 
attached to each other, or to extraneous substances. The first 
family Dorsalia, contains the genus Siliquaria (plates, fig. 1), 
known from the Serpulae, by the slit which passes through the 
whole length of the shell on the upper surface of the tube. 
The second family, Maldania, has the genus Dentalium 
(plates, fig. 2), a species of which are commonly known by the 
name of " tooth shells;" these are regularly formed, curved 
conical tubes, open at both extremities. The third family, 
Serpulacea, includes the genera Serpula, Spirorbis, Galeolaria, 
Vermilia, Spiroglyphus, and Magilus. The only shell that 
a learner would be likely to place among these incorrectly, 
according to the system, is the Vermetus (plates, fig. 345), 
which being regularly spiral at the apicial extremity, has been 
placed among the Mollusca ; to which situation the whole of 
the shells under consideration have a better title than is gene- 
rally supposed. It should be mentioned that the Serpulacea 
are provided with opercula. 

Class Cirripedes. 

This class constitutes the tenth of invertebrated animals, 
and receives its name from the jointed and ciliated branchia 
which protrude between the opercular valves. They are Mul- 
tivalve shells, and were all included in the single genus Lepas 
in the system of Linneeus, and are commonly known by the 
name " Barnacles." Lamarck has, however, divided them 
into two distinct orders. First, the Sessile Cirripedes, or those 
which being composed of several valves, joined to each other, 
side by side in a circle, are attached to each other, or to sub- 
marine bodies by the basal portion of their own substance, 
and form a hollow, irregular cone, with the aperture above 
closed by an operculum consisting of two or more valves. 
Secondly, the Pedunculated Cirripedes, which are composed of 



INTRODUCTION. 45 

valves placed in pairs against each other, so as to form a 
flattened disc attached by means of a tendinous tube called a 
peduncle. The first of these orders includes the genera 
Tubicinella, Coronula, Platylepas, Clitia, Conia, Elmineus, 
Catophragmus, Octomeris, Balanus, Creusia, Nobia, Savig- 
nium, Pyrgoma, Adna, Megatrema. The second contains 
the genera Pentelasmis, Scalpellum, Smilium, Pollicipes, 
Bisnaeus, Lithotrya, Ibla, Octolasmis, Cineras, Otion. 

Conchological writers are not agreed as to the propriety of 
allowing the above to enter into the present science. 

ClaSS CONCHIFERA. 

The shell of a conchiferous animal is always bivalve, com- 
posed of two pieces placed opposite to each other ? joined at 
the dorsal margins by an elastic hinge. All true bivalve shells 
belong to animals of this class ; and the correspondence 
between the shell and the animal is so true that on examining 
an empty bivalve shell we can not only determine that its 
inhabitant belonged to this class, but also decide on the par- 
ticular order and family in which it should be placed, without 
seeing the soft parts. 

The first general division of Conchifera is that which results 
from observing the muscular impressions, or marks made on 
the inner surface of the valve by the insertion of the adductor 
muscles. All Conchifera are divided into two orders, as fol- 
lows: 

First Order, Conchifera Dimyaria. 

Having two adductor muscles, and consequently two im- 
pressions in each valve. They are separated into the follow- 
ing families : 
1. TubicolcB (plates, fig. 44 to 54), having shelly tubes be- 
sides the valves. This family contains the genera Asper- 



46 INTRODUCTION, 

gillum, Clavagella, Teredina, Teredo, Xylophaga, Fis- 
tulana, and Gastrochsena. 

2. Pholadaria (plates, fig. 55 to 59), cylindrical, living in 

holes in rocks pierced by the animals. Lamarck places 
in this family the genera Pholas and Gastrochsena, the 
last of which belongs more properly to the family Tubi- 
colse, as placed above. 

3. Solenacea (plates, fig. 60 to 68), longitudinally (trans- 

versely, Lam.) elongated, open at the anterior and pos- 
terior extremities. This family contains the genera 
Solen, Pholadomya, Panopsea, Glycimeris (Solecurtus) 
and Solenimya. 

4. Myaria (plates, fig. 69 to 76), ligament internal. A 

spoon-shaped ligamentary pit in one or both valves. 
Shell generally gaping at one or both extremities. This 
family includes the genera Anatina, Mya, Anatinella, 
Lyonsia, Myochama, Cleidotherus. 

5. Mactracea (plates, fig. 77 to 88), the cartilage placed in 

a trigonal pit, with a small external ligament. The 
genera Lutraria, Mactra, Crassatella, Erycina, Ungu- 
ium, Amphidesma, and Solenimya belong to this family, 
the last of which ought to have been placed among the 
Solenacea, as above. 

6. Corbalacea (plates, fig. 89, 90), inequivalve, with an in- 

ternal ligament resembling the Mactracea, but differing 
in having one valve deeper than the other, although 
regular shells. This small family contains only the 
genera Corbula and Pandora. 

7. Lithophagidce (plates, fig. 91 to 97), irregular, terebrating, 

living in holes of rocks. The genera are Saxicava, 
Petricola, and Venerirupis. 

8. Nymphacea (plates, fig. 98 to 110), ligament external, 

generally placed upon a prominent fulcrum, which 



INTRODUCTION. 47 

passes from the inside to the outside of the hinge; 
valves generally gaping at the extremities. This family 
contains the genera Sanguinolaria, Psammobia, Psam- 
motoea, Tellinides, Corbis, Lucina, Donax, Capsa, and 
Crassina. 
9. Conchacea (plates, fig. Ill to 121), regular, having 
several cardinal teeth and sometimes lateral teeth. The 
Conchacea constitute one of the most beautiful and 
numerous families of the class ; they present equivalve 
shells, which are always regular, unattached, and in 
general closed, especially at the sides ; they are always 
more or less inequilateral. They are divided into the 
fiuviatile and marine Conchacea, the first containing the 
genera Cyclas, Cyrena, and Galathaea, found in rivers ; 
and the second, Cyprina, Cytherea, Venus, and Vene- 
ricardia. 

10. Cardiacea (plates, fig. 122 to 130). This family, which 

resembles the last in some general characters, are also 
regular and equivalve, and are generally provided with 
radiating ribs, which are seldom seen in the Conchacea. 
The genera enumerated in this family are Cardium, 
Cardita, Cypricardia, Hiatella, and Isocardia. 

11. Arcacea (plates, fig. 131 to 138). These are known by 

having a row of numerous small teeth on the cardinal 
hinge in each valve. The genera included are, Cucullsea, 
Area, Pectunculus, Nucula. 

12. Trigonacea (plates, fig. 139 and 140). It is doubtful 

whether this family should remain distinct. As of the 
two genera placed in it, the first, Trigonia, is thought by 
some naturalists to have strong affinities with Nucula, 
in the family of Arcacea ; and the latter, Castalia, cer- 
tainly belongs to the Nayades. 

13. Nayades (plates, fig. 141 to 152). These are fresh water 



48 INTRODUCTION. 

shells, covered on the outside by a thick horny epidermis, 
and pearly within. They include the genera Unio, 
Hyria, Anodon, Iridina. 
14. Chamacea (plates, fig. 153 to 155), inequivalve, irregular, 
foliaceous, attached; containing the genera Diceras, 
Chama, and Etheria. 

Second Order, Concliifera Monomyaria. 

Having one adductor muscle, and therefore only one im- 
pression in each valve. They are separated into the following 
families : — 

1 . Tridacnacea (plates, fig. 156 & 157), transverse, equivalve, 
with an elongated muscular impression, near the centre 
of the ventral margin ; margin undulated at the termi- 
nation of the radiated large ribs. The genera Tridacna 
and Hippopus are included. 

2. Mytilacea (plates, fig. 158 to 162), generally regular, with 

the hinge linear, without teeth, occupying the greater 
part of the dorsal margin. This family includes the 
genera Modiola, Mytilus, Pinna. 

3. Malleacea (plates, fig. 163 to 170), shell generally thin, 

inequivalve, irregular, foliaceous, with the hinge linear. 
This family contains the genera Crenatula, Perna, Mal- 
leus, Avicula, Meleagrina. 

4. Pectinides (plates, fig. 171 to 178). The Pectinides are 

generally regular or nearly so, with the shell solid ; the 
greater part of them are auriculated at the dorsal mar- 
gin, and generally characterized by ribs radiating from 
the umbones. The genera are Pedum, Lima, Plagio- 
stoma, Pecten, Plicatula, Spondylus, Podopsis. 

5. Ostracea (plates, fig. 180 to 192). The shells of this 

family are irregular, generally attached and foliaceous. 



INTRODUCTION. 49 

They compose the genera Gryphaea, Ostrsea, Vulsella, 
Placuna, Anomia. 

6. Rudistes (plates 193 to 200). This family is composed 

of a particular association of shells, which appear on one 
side to be connected with the Ostracea ; and on the 
other to approach the Brachiopoda. They differ from 
Ostracea in having no hinge or ligament, and only re- 
semble them in their irregularity and foliaceous struc- 
ture. The following six genera are placed by Lamarck 
in this family: — Sphaerulites, Radiolites, Calceola, 
Birostrites, Discina, Crania. Of these, Calceola, Dis- 
cina, and Crania are shewn to belong to the Brachio- 
poda. 

7. Brachiopoda (plates, fig. 201 to 219). The shells of 

this family are inequi valve, equilateral, and attached 
to marine bodies by a tendon passing through one of the 
valves. The animals have, near their mouth, two elon- 
gated, ciliated arms, which are spirally rolled when at 
rest. The following genera are enumerated by Lamarck, 
Orbicula, Terebratula, Lingula. 



MOLLUSCA. 

Lamarck applies, or rather restricts, this name to those in- 
vertebrated animals, which while they are inarticulate in all 
their parts, have the head sufficiently advanced at the anterior 
part of the body to be distinguished ; which is not the case 
with the Conchifera. All the shells are univalve, and are 
divided into six orders, namely, the Pteropoda, which have 
wing-shaped natatory organs or fins, and have light, thin 
transparent, nearly symmetrical shells ; the Gasteropoda, 
with the foot not distinguishable from the rest of the body, 

E 



50 INTRODUCTION. 

have patelliform, open, and scarcely spiral shells ; the Trache- 
lipoda with the foot distinct and attached to the neck of the 
animal, have spiral, non-symmetrical shells. The Cephalo- 
poda, with arms covered by suckers surrounding the head of 
the animal, have generally symmetrical convolute shells. The 
Cephalopoda are divided into C. poly thalamia, which have 
the internal cavity divided into chambers by septa, as in the 
Nautilus ; and the C. Monothalamia, which are not so divided, 
as the Argonauta. The order Heteropoda contains the genus 
Carinaria alone. 

Order Pteropoda. 

This order, containing hyaline, symmetrical, non-spiral shells, 
as above described, is not divided into families, but contains 
the following genera, Hyaleea, Cleodora, Limacina, Cymbulia ; 
the first of which, although composed of a single piece, resem- 
bles a bivalve so nearly, that Linnaeus actually placed it in his 
genus Anomia. 

Order Gasteropoda. 

With the exception of the genus Bulla and Vitrina, the last 
of which forms a passage into the next order, the shells con- 
tained in this order are patelliform, open, and scarcely spiral. 
They are divided into the following families : — 

1. Phyllidiana (plates, fig. 227 to 231), containing the 

genera Chiton, Chitonellus, and Patella, the two former 
of which present the only exception to the statement 
above made, that all the shells of Mollusca were uni- 
valve. 

2. Semiphyllidiana (plates, fig. 232 and 233). Of the two 

genera contained in this family, Pleurobranchus is broad, 
thin, and slightly spiral at the apex, and Umbrella is 
flat, circular, with a central apex. 



INTRODUCTION. 51 

3. Calyptracea (plates, fig. 234 to 246). The patelliform 

shells of this family, although united by no other general 
characters, are brought together by the characters of the 
animals which produce them. The genera are Parmo- 
phorus, Emarginula, Siphonaria, Fissurella, Pileopsis, 
Calyptraea, Crepidula, Ancylus. 

4. Bulleana (plates, fig. 247 to 253), contains the genera 

Bulla and Bullsea. 

5. Aplysiacea (plates, fig. 254 and 255). The genera 

Aplysia and Dolabella are both expanded, somewhat 
flattened shells, with the apex placed at one extremity, 
and slightly spiral. 

6. Limacinea (fig. 256 to 263). Many of the animals (slugs) 

are without shells ; some, as the Limax, or common 
garden slug, have a slightly developed calcareous piece, 
hidden beneath the mantle, and of others the shells are 
scarcely spiral. The genera included in this family are, 
Parmacella, Limax, Testacella, Vitrina. 

Order Trachelipoda . 

All the remaining spiral non-symmetrical shells are arranged 
in this order, which is divided into the following families: — 
1. Colimacea (plates, fig. 264 to 307). With the exception 
of the few contained in the family of Limacina, which 
ought not to be separated from this order, the whole of 
the land- shells are contained in this family, and although 
it is difficult to notice any one character by which terres- 
trial shells may be distinguished from others, few at all 
conversant with the subject are liable to mistake them. 
There is a general lightness and simplicity of form, 
which, though not clearly definable, is generally under- 
stood. The following distribution of genera by Lamarck, 
is generally acknowledged to require numerous modifi- 

e 2 



52 INTRODUCTION. 

cations ; the genera are Helix, Carocolla, Anostoma, 
Helicina, Pupa, Clausilia, Bulinus, Achatina, Succinea, 
Auricula, Cyclostoma. 

2. Lymneana (plates, fig. 308 to 312). The shells of this 

family are found in fresh water, wells, ditches, and 
ponds. They are of a light horny structure, and simple 
form. The genera Planorbis, Physa, and Lymnea are 
placed in this family by Lamarck. 

3. Melaniana (plates, fig. 313 to 317). These are also 

found in fresh water, principally in rivers; they are 
thicker than those of the last family ; and the greater 
part of them have elevated spires composed of numerous 
whorls. This family contains the genera Melania, 
Melanopsis, Pirena. 

4. Peristomata (plates, fig 318 to 322). These are also 

fresh-water shells, having opercula, and covered by a 
smooth green, or greenish-brown epidermis. They differ 
from the last family in having the peritreme entire. 
The genera are Valvata, Paludina, and Ampullaria. 

5. Neritacea (plates, fig. 323 to 333). The peculiarity of 

the shells of this family consists in the inner lip being 
flattened and rather straight at the inner edge. The 
genera are Navicella, Neritina, Nerita, Natica, and Jan- 
thina, the last of which forms an exception to the general 
character, and is placed by De Blainville in a family by 
itself. 

6. Macrostomata (plates, fig. 334 to 341), so named, on 

account of the large open aperture which they present 
in comparison to the spire. The shells of this family, 
which contains the genera Stomatia, Stomatella, and 
Haliotis, are pearly within. 

7. Plicacea (plates, fig. 342 to 344), contains the genera 

Tornatella and Pyramidella. 

8. Scalariana (plates, fig. 345 to 352). The genera Ver- 



INTRODUCTION. 



53 



metus, Scalaria and Delphinula, seem to have been 
placed in this family by Lamarck, on account of the 
whorls being distinct from each other. 
9. Turbinacea (plates, 353 to 371). The shells contained 
in this family are all more or less globose, or angular, 
thickened and pearly within. The following genera are 
included in this division by Lamarck, Solarium, Rotella, 
Trochus, Monodonta, Turbo, Planaxis, Phasianella, 
and Turritella. 

10. Canalifera (plates, fig. 372 to 401). The numerous 

genera of which this family is formed, namely, Ceri- 
thium, Pleurotoma, Turbinella, Cancellaria, Fasciolaria, 
Fusus, Pyrula, Ranella, Murex, Triton, are distin- 
guished by having at the anterior termination of the 
aperture, a more or less elongated canal. 

11. Alatce (plates, fig. 402 to 406). These are known by 

having the outer lip more or less expanded and gene- 
rally a posterior canal leaning towards the spire. The 
genera are Rostellaria, Strombus, and Pteroceras. 

12. Purpurifera (plates, fig. 407 to 429). In these, the 

canal, if such it may be called, is extremely short, and 
turning abruptly backwards, produces a kind of varix at 
the lower part of the whorl. The genera enumerated 
in this family are Cassidaria, Cassis, Ricinula, Purpura, 
Monoceras, Concholepas, Harpa, Dolium, Buccinum, 
Eburna, Terebra. 

13. Columellata (plates, fig. 430 to 433). The shells of this 

family are emarginated at the anterior extremity of the 
aperture, and the inner lip is characterized by plates or 
folds, which, with the exception of those on Columbella, 
are distinct. The genera are Mitra, Voluta, Margi- 
nella, Volvaria, Columbella, the latter of which would 
be better placed among the Purpurifera. 



54 INTRODUCTION. 

14. Convolutce (plates, fig. 444 to 462). The well-known 
shells contained in this family are distinguished for the 
small proportion of the spire, if any, which remains un- 
covered by the last whorl. They might be well divided 
into two groups, the first containing the genera Ovulum 
and Cyprsea, under the name of Cyprseadse, which are 
truly convolute, having the spire entirely hidden ; and 
the second containing the genera Oliva, Ancillaria, and 
Conus. 

Order Polythalamous, or Chambered Cephalopoda. 

The greater part of the shells belonging to this order are 
symmetrical, and the internal cavity is divided into separate 
compartments, by plates called Septa. It is divided into the 
following families : — 

1. Orthocerata (plates, fig. 463 to 470), containing the 

genera Belemnites, Orthoceras, Nodosaria, Hippurites, 
and Conilites. Hippurites certainly has no affinity with 
the Cephalopoda, but is ascertained to be a bivalve 
shell, properly belonging to the family Rudistes; the 
other genera are straight, elongated, and conical. 

2. Lituacea (plates, fig. 471), containing the genera Spirula, 

Spirulina, and Lituola, the two latter of which are 
microscopic. 

3. Cristacea, containing the microscopic genera Renulina, 

Orbiculina, and Cristellaria. 

4. Spheridacea, containing the microscopic genera Miliola, 

Gyrogona, and Melonia. 

5. Radiolacea, containing the microscopic genera Rotalites, 

Lenticulina, Placentula. 

6. Nautilacea (plates, fig. 472 to 476). This family con- 

tains the following genera — Discorbites, Siderolites, 
Polystomella, Vorticialis, Nummulites, and Nautilus ; 



INTRODUCTION. 55 

the two latter of which alone are now received in cabinets 
of shells, the four former belonging to that class of 
microscopic fossils, now termed Foraminifera ; the genus 
Nummulites, although large, may probably belong to 
the same class, and perhaps it would have been better 
to have included the remaining genus, Nautilus, in the 
next family, from which it differs in having the septa 
which divides the chambers simple at their edges. 
7 , Ammonacea (plates, fig. 477 to 484). The edges of the 
septa of these are all more or less sinuous and com- 
plicated. This family contains the following genera, 
Ammonites, Ammonoceras, Baculites, and Turrilites, 
the latter of which presents a singular anomaly in 
having an oblique spire, like that of the order Tracheli- 
poda, while it is divided into chambers by sinuous septa. 

Order Monothalamous Cephalopoda. 

The only shells included in this order belong to the genera 
Argonauta (plates, fig. 485), placed here by Lamarck, and 
Bellerophon (plates, fig. 486 and 487), a fossil genus subse- 
quently added. 

Order Heteropoda. 

The singular and beautiful transparent shell contained in 
this order, under the generic name Carinaria, forms a cover- 
ing to a small portion of an animal, equally remarkable and 
equally distinct from those of all other orders. 

The above arrangement, although far from perfect, and 
requiring numerous modifications, is perhaps liable to as few 
objections as any other yet proposed, and will certainly be 
more easily understood by those who have not the opportunity 
of studying the soft parts of the animal. 



CONCHOLOGICAL MANUAL. 



ABIDA. Leach. A genus founded on a species of Pupa, which 
has the peristome slightly reflected, and numerous plaits in the 
aperture. Pupa Juniperi, Pupa secale, Draparnaud. Great Britain; 
also Central and Southern Europe. 

ABRA. Leach. A genus composed of Amphidesma tenue, pris- 
maticum, and other small thin species. British Channel and 
Mediterranean. Fam. Mactracea. 

ABSIA. Leach. Lithotrya, Sowerby. Fam. Pedunculated Cir- 
ripedes. 

ACAMAS. Montfort. Belemnites multiforatus, Blainville. A 
species described as being perforated at the apex, by a stellated 
perforation. No species of Belemnite at present known agreeing 
with the description ; it is supposed to have been taken from a 
broken specimen. 

ACANTHOCHETES. A name given to a species of Chiton having 
bunches of bristles at the sides of the valves. 

ACARDO. Commercon. Described from a pair of bony plates, 
taken from the vertebrae of the Whale, and mistaken for a bivalve 
shell, destitute of a hinge. 

ACARDO. Swainson. A generic term applied by Swainson to the 
nearly toothless species of Cardium, named C. edentulum by some 
authors ; C. Greenlandicum by others: fig. 123*. 

ACASTA. Leach. Order, Sessile Cirripedes, Lamarck. Balanus 
Montagui, Sowerby. A small genus separated from Balanus, on 
account of the cup-shaped base, but re-united by Sowerby, who 
shews, in his Genera of Shells, that this is a merely accidental 
circumstance, resulting from the situations in which the shells ac- 
quire their growth. If, for instance, the Balanus be attached to 



58 ACHATINA. 

a flat surface, in an open situation, the base will be short and flat; 
if it be placed in a hollow among other growing substances, it 
will be lengthened out in order that the aperture of the shell may- 
be even with the outer surface of the surrounding mass ; and if, 
as in the Acastse, it be imbedded in a soft and loose substance, 
the base, being left to itself, will take a regular form. The 
Acastse are found imbedded in sponges. Ex. Balanus Montagui, 
of Great Britain, flg. 26. Also found in the Pacific ocean and 
Philippines. 

ACAVUS. Montfort. Fam. Limacinea, Blainville ; Colimacea, 
Lamarck. A division of the genus Helix, which may be con- 
sidered synonymous with De Ferrusac's sub-genus Helicogena. 
De Montfort has given H. Hsemastoma, as an example. Fig. 26/. 

ACCESSARY VALVES, are the smaller or less important testaceous 
plates, found on the hinge or dorsal margins of the true valves of 
some shells. Example, the small plates on the hinge of Pholas, 
fig. 55, a. The Pholades were placed by Linnseus and Bruguiere 
among multivalve shells. 

ACEPHALOPHORA. Blainville. («, without ; KefaXe, head.) 
The third class of the type Malacozoaria, Bl. including all bivalve 
shells, the animals of which have no distinct head This class 
corresponds with the Conchifera of Lamarck, and is divided into 
the orders Palliobranchiata, Rudistes, Lamellibranchiata, and 
Heterobranchiata, the last of which contains no genera of testa- 
ceous Mollusca. 

ACHATINA, Auctorum. Fam. Colimacea, Lam. (from Achates, 
an agate.) Fam. Limacineee, Bl. Gen. Polyphemus, Montf. — 
Desc?\ Shell oval or oblong, sub-turrited, light, thin ; aperture 
oval, or pyriform ; outer lip sharp ; columella smooth, tortuous, 
truncated, so as to form a notch at its union with the outer lip. 
— Obs. It is from this notch that we are enabled to distinguish 
Achatinee from Bulini, which, moreover, generally have a reflected 
outer lip. The Polyphemi of Montfort have an undulation in 
the centre of the outer lip. Achatina Virginea, fig. 286. Poly- 
phemus Glans, fig 288. These land shells are found in various 



ADESMACEA. 59 

parts of the globe, but attain the greatest size and richness of 
colouring in tropical climates ; particularly in the West India 
Islands. 

ACHATINELLA. Sow. A small group of shells, differing from 
Achatina in having the inner edge of the outer lip thickened, and 
a slight groove near the suture of the spire. Fig. 287. Sand- 
wich Islands. 

ACHELOIS. Montf. Conilites Achelois. Knorr. Supp. T. 4, fig. 1 . 

ACICULA. Nilson. Achatina Acicula, Auct. Cionella, Jeffreys. 

ACIONA. Leach. A genus described by De Blainville as consisting 
of those species of Scalaria, the whorls of which do not touch each 
other. If this account be correct, the genus proposed by Leach 
will include the typical species of Scalaria, such as S. pretiosa. 

ACME. Hartmann. A genus formed of Turbo fuscus, Walker. 
Auricula lineata, Drap.thus described — " Shell sub-cylindrical, 
with a blunt tip; mouth ovate, simple, thin, slightly reflected over 
the pillar, forming a slight perforation." The animal is said to 
resemble a Cyclostoma, but has no operculum. Auricula lineata, 
Drap. Hist. 57, t. 3, fig. 20, 21. Southern Europe. 

ACTEON. Montf. Tornatella, Lam. 

ACTINOCAMAX. Stokes. A genus of Belemnitiform Fossils. 

ACULEATED. Beset with sharp spines, as the margin of Chiton 
aculeatus, fig. 227. 

ACUMINATED. Terminating in a point, as the apex of Melania 
subulata, fig. 313. 

ACUS. Humphrey. Terebra of Lamarck. 

ACUTE. Sharp, pointed, or sharp-edged. 

ADDUCTOR MUSCLE. That which draws the two valves of a 
shell together, and leaves a mark on the inner surface of each, 
called the Muscular Impression. 

ADELOSINA. D'Orb. A genus of microscopic Foraminifera. 

ADESMACEA. Bl. (a, without ; Acer/ioj desma, ligament.) The 
10th family of the order Lamellibranchiata, Bl. composed of 
Mollusca which either bore tubular dwellings in rocks, wood, &c. 
or live in testaceous tubes, their shells being consequently desti- 
tute of the hinge ligament. The action of opening and shutting 



(0 



AKERA. 



the valves being limited to the narrow space to which they are 
confined, or else the valves themselves being soldered into the 
tube, renders it unnecessary for them to have a ligament to keep 
them in their places. The genera Pholas, Teredina, Fistulana, 
and Septaria, belong to this family, which corresponds in part 
with the families Tubicolaria and Pholadaria, of Lamarck. 

ADNA. Leach. One of the genera separated by Leach from 
Pyrgoma, and characterized as consisting of an upper valve, 
supported on a funnel-shaped base, which is not buried in the 
coral to which it is attached, like Pyrgoma, but is seen 
externally. The operculum consists of four valves. Adna, fig. 32. 
British Channel and Mediterranean. 

ADNATE. A term applied by some authors to those shells belong- 
ing to the family of Unionidse, which have the valves joined 
together at the dorsal margin, not like other bivalves, by a 
distinct ligament, but by the substance of the shell itself, the 
valves appearing to grow together in such a manner that they 
cannot be separated without one of them being broken as will be 
seen in our figure of Dipsas plicatus, fig. 142. This circumstance 
has been made the foundation of specific and even generic dis- 
tinctions, for which however it is insufficient, because many 
species which when young are " adnate," when fully grown 
have their valves joined together only by a ligaments 

MGLIA. Say. A division of " Unionidse," described as having the 
tl shell cuncate ; bosses prominent ; cardinal teeth much com- 
pressed, placed on one side of the bosses. iEglia ovata, Say. 
Occidens Lea. Am. Tr. iii. pi. 10." Lardner's Encyclopedia of 
Malacology. 

AGANIDES. Montf. Orbulites, Lam. 

AGATHIRSES. Montf. Siliquaria, Auct. 

AGINA 1 Belongs to Saxicava, Auct.' 

AKERA. BL The fourth family of the order Monopleurobran- 
chiata, Bl. containing the genera Bulla, Bullsea and Bellerophon, 
which, excepting the last, constitutes the family Bullseana, Lam. 

AKERA* A genus of extremely light, horny shells, resembling 
Bulla, from which it differs, in the outer lip being separated 



AMICULA. 61 

from the body whorl, which is elastic. Ex. Bulla fragile, 
fig. 247. 

ALiEA. Jeffrey's. A genus of minute land shells, resembling 
Vertigo, but separated because they are dextral, while Vertigo is 
sinistral. Ex. fig. 292. A. marginata, Pupa marginata, Drap. 
found in marshy ground, roots of trees, moss, &c. Britain and 
Southern and Central Europe. 

ALASMODON. Say. A division of the genus Unio, Auct. con- 
sisting of those species which have cardinal, but no lateral 
teeth. Ex. A. complanatus, fig. 141. North America and Europe. 

ALATiE. Lam. A family of the order Trachelipoda, Lam. con- 
taining the following genera which may be thus distinguished. 

1. Rostellaria. Sinus close to the canal ; including Hip- 
pochrenes, and Aporrhais, Fig. 402 to 404. 

2. Strombtjs. Sinus not close to the canal. Fig. 406. 

3. Pteroceras. Same, digitated. Fig. 405. 

ALATED. (From Ala, a wing.) Winged, a term applied to shells, 
when any portion of them is spread out in any direction, as in 
fig. 403. Hippochrenes, Montf. and fig. 147, Unio Alatus. 

ALCADIA. Gray? (B. M. Syn. p. 134) Helicinee which have a 
notch in the aperture. A distinction which it is impossible to 
maintain. See Helicina. 

ALATUS. Humphrey. Strom bus, Auct. 

ALECTRION. Montf. Buccinum Papillosum, Auct. fig. 422. 

ALEPAS. Rang. A genus of Pedunculated Cirripedes without a shell. 

ALVEOLINA. D'Orbigny. A genus of microscopic Foraminifera. 

AMALTHUS. Montf. A. margaritaceus, Montf. is a species of 
Ammonites described as very flat, keeled, with an angular aper- 
ture- It belongs to the family Ammonacea, Lam. 

AMARULA— ? A genus composed of Melania Amarula, 

Auct. and similar species. 

AMBIGU^E. Lam. The fourth section of the order Conchifera 
Dimyaria, containing the family Chamacea, fig. 153 to 155. 

AMICULA. A genus formed for the reception of Chiton amicu- 
latus, Auct. the valves of which are covered by an integument; so 
as to be completely hidden externally. 



62 AMMONOCERATITES. 

AMIMONUS. Montf. Conilites ungulatus, Knorr. A species 
distinguished only by being slightly curved ; Fam. Orthocerata, 
Lam. 

AMMONACEA. Bl. The fourth family of the order Polythalamia, 
Bl. or chambered shells, described as thin, chambered, discoidal, 
convolute, symmetrical, generally compressed, with visible whorls. 
This last character is used in De Blainville's System to dis- 
tinguish the Ammonacea from the Nautilacea. This family 
contains the genera Discorbites, Scaphites, Ammonites, and 
Simplegas. 

AMMONACEA. Lam. The seventh family of Polythalamous 
Cephalopoda, Lam. containing the genera Ammonites, Orbulites, 
Ammonoceras, Turrilites and Baculites, to which may be added 
Amalthus, Simplegas, Ellipsolites, Nautellipsites, Hamites, Icthy- 
osavcolites, and other genera mentioned in the list of figures 
4/7 to 484. 

AMMONITES. Auct. (from Jupiter Ammon.) Fam. Ammonacea, 
Lam. and Bl. — Descr. Symmetrical, convolute, discoidal, orbicular; 
chambers numerous, divided by lobated, branched or sinuous 
septa, perforated by a Siphon ; aperture generally more or less 
modified by the last whorl. The fossils of the secondary strata 
which compose this genus are numerous and well known ; they 
are vulgarly termed ". snake-stones," and some of them are 
extremely beautiful, particularly when the internal structure is 
exhibited by a section. There is some difficulty in distinguishing 
them from the Fossil Nautili, for although the whorls, being visible 
and the Septa sinuous, may be taken as the characteristics of the 
Ammonites, yet there are several species which partake the 
characters of both. The Orbulites of Lamarck (fig. 479) for 
instance, have sinuous septa like Ammonites, but the last whorl 
covers those which precede it as in Nautilus- Simplegas 
Montf. and Bl (fig. 475) has the whorls visible externally and 
the septa simple. Ammonites is figured in the plates (478). 

AMMONOCERAS, orj ■' ' : 

AMMONOCERATITES. \ W (fr ° m Jmmon & K ^ cera8 ' hom " ) 
The shells described under this Lamarckian genus present an 



AMPLEXUS. 



03 



anomaly which is considered hy Mr. G. B. Sowerby, sen., as merely 
accidental. They resemble the Ammonites in internal structure, 
but instead of being spirally convolute they are merely curved like 
a horn. Ex. fig. 477, copied from De Blainville. 

AMNICOLA. The name of a genus mentioned in the family of 
Melaniana in the conchological part of the Synopsis of the British 
Museum, but unexplained. 

AMPHIBOLA 1 The same as Ampullaria, Auct. 

AMPH1BULIMA. Lam. Succinea Patula, Auct. (fig. 266.) was 
first published in the Ann. du. Mus. D'Hist. Nat. under the name 
Amphibulima cucullata. The generic name was afterwards aban- 
doned by its author, and the species stands in his system as Suc- 
cinea cucullata. West Indies. 

AMPHIDESMA. Lam. (from Afi^o), ampho, ambo, Aeafioc, desmos, 
ligamentuni). Fam. Mactracea, Lam. — Bescr. Equivalve, oval or 
rounded, sub-equilateral, sometimes rather gaping at the sides, with 
slight posterior fold ; hinge with one or two cardinal teeth in 
each valve, and two elongated lateral teeth, distinct in one valve, 
nearly obsolete in the other ; ligament short, separated from the 
cartilage, which is elongated and couched obliquely in an exca- 
vation of the hinge. — Obs. In most bivalve shells, the cartilage 
and ligament are united in one mass, or placed close to each other; 
the contrary in this case gives rise to the name, which signifies 
double ligament. This circumstance distinguishes the genus 
Amphidesma from Tellina, which in other respects it greatly 
resembles. From Lutraria it may be known by its distinct 
lateral teeth, and also by its valves being nearly close all round, 
while the Lutrarise gape anteriorly. The species do not appear 
to be numerous, no fossil species are known. A. Reticidatum, 
fig. 85. West India Islands, Brazil, Coast of Pacific, &c. 

AMPHIPEPLEA. Nilson. The type of this proposed genus is 
Limnea glutinosa, Auct. Gray's edition of Turton, page 243, 
plate 9. fig- 103. The shell is polished and the inner lip expanded. 

AMPHISTEGINA. D'Orb. A genus of microscopic Foraminifera. 

AMPLEXUS. J. Sowerby. A. Corralloides, fig. 463. A singularly 
formed fossil, described as nearly cylindrical, divided into cham- 



64 ANALOGOUS. 

bers by numerous transverse septa, which embrace each other with 
reflected margins. It occurs in the Dublin limestone, and re- 
sembles a coral or madrepore. 

AMPLEXUS. A generic name proposed by Captain Brown for 
Helix pulchella, Drap. 112, tab. 107-134. Zurama, Leach. 

AMPULLARIA. Auct. {Ampulla, a rounded vessel). Fam. < k Peris- 
toiniens," Lam. Ellipsostomata, Bl. — Descr. Spiral, globular, some- 
times discoidal, frequently umbilicated, covered with a rounded, 
horny epidermis ; spire short ; whorls rapidly enlarging ; aper- 
ture elliptical, rounded anteriorly ; peristome nearly or quite 
entire, thickened and slightly reflected ; operculum, testaceous, 
annular, with a subcentral nucleus.— Obs. This genus of fresh- 
water shells of which a few fossil species occur, is easily distin- 
guished from other genera, by obvious characters, particularly by 
a thick, horny, greenish-brown epidermis, and the rotundity in 
form. One species, the A. Cornu-arietis which forms the type 
of Lamarck's genus Planorbis, requires notice on account of its 
flatness, but may be known by the aperture which in the Ampul- 
laria is longer than wide, and in Planorbis the contrary. Lanistes, 
Montf. is described from a reversed species of Ampullaria. The 
Ampullaria is vulgarly called the Idol Shell, and is said to be held 
in great veneration by the South American Savages. The animal 
has a large bag, opening beneath, placed on the side of the res- 
piratory cavity. It is supposed that the animal has the power 
of filling this bag with water, and that it is thus enabled to live a 
long time out of water. They have been brought as far as from 
Egypt to Paris alive, packed in saw-dust. Ex. fig. 318. East 
and West Indies, North Africa, South America, &c. 

AMPULLAMNA ? A genus formed for the reception of 

Ampullaria avellana. Fig. 538. From Australia. 

AMPULLINA ? Part of the genus Helicina, Auct. 

ANALOGOUS. A term applied to certain species of fossil shells, 
which present a certain degree of resemblance to recent species; 
but which are not sufficiently similar to warrant the use of the 
term * identical,' or any other implying that they are of the same 
species. 



ANATINA. 65 

ANASTOMA or ANOSTOMA. Fischer, (from Ava, ana, back- 
wards ; 2ro/xa, stoma, mouth) Fam. Colimacea, Lamark. A genus 
of land shells so named from the singular circumstance of the 
last whorl taking a sudden turn and reflecting the aperture up- 
wards, so as to present it on the same plane with the spire ; so 
that the animal walks with the spire of the shell downwards 
resting on the foot. In other respects, the two species of which 
this genus is composed, resemble other Helices ; and belong to 
De Ferrusac's division " Helicodonta." Tomogerus is De Mont- 
fort's name for this genus. A. depressum is represented in the 
plates figs. 271, 272. The nearest approach to this genus will be 
found in the fossil shell named Strophostoma, by Deshayes, 
which, however, has no teeth in the aperture and is provided with 
an operculum like Cyclostoma. South America. 

ANATIFER. Brug. ANATiFA ? Lam This name, which signifies 
Duckbearing, has been given to the shells commonly called Bar- 
nacles, on account of an absurd notion entertained among the 
ancients, that they inclose the young of the Barnacle duck, in 
an embryo state. The beautiful bunch of jointed arms, the cilise 
of which serve the purpose of agitating the water, so as to draw 
in food by the current, were supposed to be the feathers of 
the future bird. For a description of these shells, see Pente- 
lasmis ; and fig. 34. 

ANATINA. Lam. {That which belongs to a duck) Fam. Myaria, 
Lam. Pyloridea, Bl. — Bescr. Thin, transparent, generally equi- 
valve, inequilateral, transverse, marine ; hinge with a spoon- 
shaped process in each valve, containing the cartilage. — Obs. 
Some species included in the genus Anatina of authors, A. striata, 
for instance, have not the spoon-shaped prominence, but in its 
place a small, testaceous, moving appendage, connected with the 
interior of the hinge. These are now separated, and form the 
genus Lyonsia. The genus Nseara, Gray, is composed of Anatina 
longirostrum, and similar species, which have neither the bony 
appendage nor the spoon-shaped prominence. Mya is distin- 
guished from Anatina, by the thickness of the shell, and also by 
having the prominence only in the hinge of one valve. Fig. 69. 

F 



66 ANCULOSA. 

A. rostrata. The Anatinae are found in the East Indies and 
South Sea Islands. 

ANATINELLA. G. B. Sowerby. (Dimunition of Anatina). A 
genus so named from its resemblance to Anatina, from which it 
differs in being destitute of the internal appendage, and having 
no sinus in the palleal impression. One species having been 
brought from Ceylon, received the name of Anatinella Sibbaldii. 
Another has lately been found in the Philippine Islands. Fig. 70. 

ANATOMUS. Montf. Tom. 2, plate 279. A microscopic shell, 
appearing from the figure to resemble Scissurella. 

ANAULAX. Brogn. Ancillaria, Auct. 

ANCILLA. Lam. Ancillaria, Auct. 

ANCILLARIA. Auct. Ancilla, Lam. {A handmaid.) Fam. 
convolutce, Lam. Angyostomata, Bl. — Descr. Smooth, oblong, 
subcylindrical. Spire short, sutures hidden by enamel. Aper- 
ture long, anteriorly emarginated and somewhat effuse. Colu- 
mella tortuous, oblique, tumid, truncated. — Obs. The Ancillarise 
are pretty shining shells, enveloped almost entirely by the soft 
parts of the animal. They resemble Oliva, from which they are 
distinguished by the suture of the spire being filled up with shelly 
enamel, nearly covering the surface. The whorls in Oliva being 
separated by a distinct canal. Ancillaria may be known from 
Terebellum by the tumid varix at the base of the columella. 
The well known Ivory shell, Eburna glabrata, Lam. belongs to 
this genus, of which a few fossil species are found in the London 
clay, Calcaire grossier and green sand, Turin. The recent species 
are found in the Islands of the Indian Ocean and Australian 
Seas. A. glabrata is represented in the plates fig. 455 ; A. cin- 
namonea, fig. 456. 

ANCULOSA. Say. Fam. Melaniana, Lam. Ellipsostomata, Bl. 
A genus proposed to include some fresh-water shells resembling 
those of the genus Melania, the difference between them being 
that the spire of Anculosa is more depressed, and the anterior of 
the outer lip more angulated than in Melania. On an examina- 
tion of the different species, however, it will be found that this 
is quite unsatisfactory, as a generic distinction ; because some of 



ANNULUR OPERCULUM. 67 

the species with short flattened spires, have rounded, and others 
angulated apertures. North America. An example of each is 
represented, fig. 314. 

ANCYLUS. Geoffroy. Fam. Calyptracea, Lam. Otides, Bl. — Descr. 
Thin, obliquely conical, patelliform ; apex acute, turned sidewise 
and backwards ; aperture oval ; margin simple. — Obs, Although 
the little fresh-water shells described under this name, resemble 
those of the genus Patella, the animals which produce them are 
nearly allied to the Lymneanse. And, it may also be observed, 
that the shells themselves differ from Patella in not being quite 
symmetrical, having the apex turned on one side. A. fluviatilis, 
fig. 246. Found in Great Britain, and in Southern and Central 
Europe, West Indies, &c. 

ANDROMEDES. Montf. Vorticialis, Lam. Fam. Nautilacea, 
Lam. A genus of microscopic Foraminifera. 

ANGULATED. (Angulatus.) Having an angle, or corner, as the 
anterior of the aperture of Eulima, fig. 348 ; the posterior side 
of Castalia, fig. 140 ; the whorls of Carocolla, fig. 277. 

ANGULITES. Montf. A genus composed of species of fossil 
Nautili, described by De Blainville as not umbilicated, with a 
dorsal keel and angular aperture. Nautilus triangularis Buffon. 

ANGIOSTOMATA. Bl. The third family of Siphonobranchiata, 
Bl. described as differing little from the family of Entomostomata, 
but having long, narrow, straight apertures, and the columellar 
lips straight or nearly so. Were it not for the admission of the 
genus Strombus into this family, it would correspond with 
Columellaria and Convolute of Lamarck. 

ANNELIDES. The ninth class of invertebrated animals, divided 
into three orders, namely, A. Apodes, A. Antennes, and A. Seden- 
taires. The last only contains families of testaceous Mollusca. 
The animals are vermicular, some naked, others inhabiting shelly 
tubes. See Sedentary Annelides. 

ANNULAR OPERCULUM is one which has the nucleus central, 
or nearly so, the other layers surrounding it in flattened rings. 
The term concentric is also applied. See Introduction. 

f2 



68 ANTERIOR. 

ANNULATED. (Annus, a ring.) Composed of, or surrounded by 
rings, as in the case of Tubicinella, fig. 14. 

ANODON. Brug. Fam. Submytilacea, Bl. Nayades, Lam. A genus 
composed of such species of Nayades as are destitute of teeth 
on the hinge. Europe, North America, &c. An example is given 
in A. Cataractus, fig. 152. 

ANOMALINA. D'Orb. A genus of microscopic Foraminifera. 

ANOMIA. Fam. Ostracea, Lam. and Bl. — Descr. Irregular, in- 
equivalve, sub-equilaternal, foliaceous, pearly within ; adhering 
to marine substances by means of a bony appendage, which passes 
through a large circular opening in the lower valve ; muscular 
impression divided into three irregular portions ; hinge destitute 
of teeth with a short cartilage. — Obs. The Linnsean genus in- 
cluded not only the shells to which the description above given 
would apply, but also many other genera, such as Crania, Orbicula, 
Terebratula, &c. which belong to the Brachiopoda, and are per- 
fectly distinct. The Anomise are found in Europe, N. America, 
Moluccas, Philippine Islands, &c. Fig. 186, in the plates, is a 
somewhat reduced representation of a full grown specimen of 
A. Ephippium. Fig. 187, the hinge of the under valve, with the 
bony process. Fig. 1S8, the hinge showing the opening through 
which it passes. 

ANOSTOMA. See Anastoma. 

ANSATES. Klein. A genus formed of those species of Patella 
which have a produced, recurved beak. Helcion, Montf. Ex. 
Patella pellucida, fig. 230. 

ANSULUS or ANSYLUS. Mr. Gray conjectures that the name of 
the genus Ancyius, should be so written. 

ANTENOR. Montf. A genus of microscopic Foraminifera. 

ANTERIOR. In Bivalves is the side on which the head, or part 
analogous to the head of the animal lies ; it is known in the 
shell by the umbones, which if turned at all, are turned towards 
that part. If there be a sinus in the impression of the mantle, 
it is always on the posterior part of the shell. Jf the ligament 
be placed only on one side of the umbones, it is only on the 



APERTURE. 69 

posterior side. The anterior of a spiral univalve is that part of 
the outer lip which is at the greatest distance from the apex. Of 
a symmetrical conical univalve such as Patella, it is that part 
where the head of the animal lies, indicated by the interruption 
of the muscular impression. Of cirripedes> that part where the 
ciliae protrude are anterior ; of Brachiopoda, that part which 
is farthest from the umbones and which corresponds with the 
ventral margin in other Bivalves. The anterior of symmetrical, 
convolute univalves, is the outer or dorsal part of the aperture, or 
that part which is farthest from the spire. Lamarck and other 
Conchological writers have occasioned much confusion by their 
errors on this subject ; describing the same part of a shell at 
one time anterior, at another posterior ; but generally the reverse 
of the above arrangement, which is founded upon the natural 
position of the animal, and generally adopted. The anterior will 
be indicated by the letter a, in figs. 119, 421, 229, 34, 202. 
ANTIGONA. Schum. A genus composed of Venus cancellata, 

Lam. (fig. 119.) and similar species. 
ANTIQUATED. This word, signifying out of date, is occasionally 
used to express that species of composition which constantly 
occurs in shells, by each fresh deposit or layer of calcareous 
matter, forming a new margin, which being replaced by its suc- 
cessor, is no longer used as the margin, and is consequently said 
to be out of date. 
APEX. This term does not apply to the natural position of a 
shell, but is used in a mathematical sense, to indicate the nucleus 
or first formed part ; which may be considered as the point of 
the spiral cone. From this point, the shell enlarging rapidly or 
slowly as it descends, takes a spiral, arched, straight, oblique, 
convolute, or irregularly spiral course. The apex will be in- 
dicated by the letter a, in fig. 282 and 466. 
APERTURE or MOUTH. The entrance to the spiral cavity of 
univalve shells. The parts of the aperture are separately de- 
scribed, as follows : The inner lip or labium is that part which 
lies over the preceding whorl of the shell. It terminates an- 
teriorly, or towards the lower part in what is termed the columella, 



70 APLYSIA. 

so called because it forms a kind of axis on which the volutions 
turn. The outer lip, sometimes called the labrum, is on the 
opposite side, or the farthest from the axis. If the edges of the 
inner and outer lips unite all round, they are described as com- 
posing theperitreme. In fig. 318, the aperture is marked by the 
letter a. 

APHRODITA. Lea. (from A(j>pohrfj, Greek name of Venus.) 
A genus composed of Cardium Groenlandicum, Auct. fig. 123*, 
and other similar species of Cardium, the teeth of which are 
either wholly wanting, or very indistinct. Northern Ocean. 

APICIAL. Belonging to the apex. The apicial extremity of the 
aperture of a univalve shell, is that which is nearest to the apex 
of the spire. 

APICULUM. Humph. Trochus, Lam. 

APLEUROTIS. Rafinesque. A genus unfigured and imperfectly 
described as differing in some respects from Terebratula and other 
Brachiopodse. 

APLEXUS. Fleming. A genus composed of Physa Hypnorum, 
Drap. &c. and described as having the inner lip simple, and not 
spread over the body whorl. 

APLODON. Rafinesque. A genus proposed to be established at 
the expense of the genus Helix, but upon what grounds does 
not appear from the imperfect description which is unaccompanied 
by a figure. 

APLUSTRE. Schum. A genus formed for the reception of those 
species of Bulla which have the spire uncovered. Ex. Bulla 
Aplustre, (aplustre, a flag.) Auct. fig. 289. 

APLYSIA. Linn. («, without ; U\vo>, to wash.) Fam. Laplysiens, 
Lam. Aplysiana, Bl. — Descr. Horny, transparent, clypeiform, or 
shield- shaped, placed horizontally on the back of the animal, with 
its convex side uppermost ; apex slightly incurved. — Obs. The 
animal producing this shell has derived its name from the purplish 
liquor which it exudes, when disturbed. In contour, it has been 
fancied to present a certain likeness to a hare crouching, and on 
this account was called Lepus marinus, or sea hare, by the ancients. 
The shell bears a strong resemblance to Dolabella, which, however, 



ARCA. / ! 

is much thicker, and more testaceous. The species are found in 
the Mediterranean, European, and West Indian Seas. A. Peter- 
soni, fig. 254. 

APLYSIACEA. Bl. The second family of the order Monopleuro- 
branchiata, Bl. The animals composing this family are either 
destitute of shells, or are provided with internal ones, which are 
flat, open, oblique, with the apex or nucleus slightly incurved, 
not distinctly spiral. This family contains the genera, Aplysia 
and Dolabella. The first sub-spiral, with the apex terminal; 
shell thin, horny. Fig. 254. The second the same, but thick 
and shelly. Fig. 255. 

APOLLON. Montf. Ranella Ranina, Auct. Placed by De 
Blainville in that division of Ranella, which is characterized as 
being umbilicated. Fig. 393. 

APOROBRANCHIATA. Bl. The first order of the second section 
of Paracephalophora Monoica, Bl. The Thecosmata is the only 
family of this order containing any approach to shells, these are 
Hyalsea and Cymbulia. 

APORRHAIS. Petiver. A genus formed of Rostellaria Pes- 
pelicani, Auct, (fig. 404) and similar species. Although the shell 
presents no characters to distinguish it generically from Rostel- 
laria, those who have examined the soft parts are convinced that 
it is distinct. Of the three species now known and figured in 
part I. of Thesaurus Conchyliorum, by the Author, one is com- 
mon on our own coast, and in the Mediterranean ; also North 
America. See Rostellaria. 

AQUATIC. A term applied by some authors to those species of 
Molluscous animals, which inhabit fresh water, either in rivers, or 
salt water standing pools, as distinguished from the marine or 
Mollusca. See Fresh-water. 

AQUILLUS. Montf. Triton Lampas, Cutaceus, &c. Auct. 
Placed by De Blainville in the division of the genus Triton, 
which is described as having a short spire, being covered with 
tubercles and umbilicated. Triton Cutaceus, fig. 399. 

ARCA. At 't. (Anglice, a boat.) Fam. Arcacea, Lam. — Bescr. 
Obliquely transverse, subquadrate, equi valve, or nearly so, 



72 ARCINELLA. * 

inequilateral, thick, ventricose, longitudinally ribbed, dentated 
near the inner margins ; hinge rectilinear, forming a flat, external 
area, upon which the ligament is spread in cross rows, and 
having a series of small, regular teeth, extending on both sides of 
the umbones in each valve ; muscular impressions distant. — 
Obs. The shells composing this genus are easily distinguished 
from those of all other bivalve shells, by the straight, linear row 
of small, notched teeth, and by the area between the umbones. 
The genus Cucullcea makes the nearest approach to it in this 
respect, but it may easily be known from it by the outermost 
teeth on each side of the row being oblique, and lengthened out; 
and also by the prominent edge of the muscular impression. 
These shells are found recent, in various marine localities ; fossil, 
in the tertiary deposits. The Area Nose, formerly regarded as 
the type of this genus, has, with several other species, been 
separated from it under the name of Bysso-arca, by Swainson, 
on account of an hiatus in the ventral margin, to admit the 
passage of a byssus ; this is not found in the true Arcse. The 
true Arcse are mostly tropical. Area Antiquata, fig. 131 . Bysso- 
arca Nose, 132. 
ARCACEA. Lam. A family of the order Conchifera Dimyaria, 
characterized by a series of teeth placed on the hinge in a line. 
The genera may be distinguished as follows, 

1. Arc a. Hinge straight ; valves close. Fig. 131. 

2. Bysso-arca. Valves gaping. Fig. 132. 

3. CucuLLiEA. Distant teeth oblique ; posterior muscular 

impression prominent. Fig. 133. 

4. Pectunculus, Hinge curved. Fig. 134. 

5. Nucula. The same, with a pit in the centre of the hinge, 

including Myopara and Crenella. Figs. 135 to 137- 

6. Solenella. Fresh water, oval ; a series of teeth on one 
side of the hinge, only two or three on the other. 
Fig. 138. 

ARCHAIAS. Montf. A genus of microscopic Foraminifera. 
ARCHONTE. Montf. Hyal^a, Auct. 
ARCINELLA. Schum, Chama Arcinella, Auct. 



ARGONAUTA. / 6 

ARCTICA. Schum. Cyprina Icelandica, Auct. 

ARCUATED. (Arcus, an arch.) Bent, in the form of an arch, as 

Dentalium, fig. 2« 
AREA. A flat space or disc, on any part of a shell. As for instance, 
the triangular space on the hinge of Area, fig. 132, and 
Spondylus. 
ARENACEOUS. (Arena, sand.) Of a sandy texture, as the sand 
tubes surrounding the bodies of some of the Annellides, named 
Arenaria on this account. But the word is more commonly 
used to intimate the habits of the animal, burrowing with its 
shell in the sand. 
ARETHUSA Montf. A genus of microscopic Foraminifera. 
ARGONAUTA. Auct. Commonly called the " Paper Sailor/' 
Fam Pteropoda, Bl. Order Cepholopoda Monothalamia, Lam. 
— Descr. Light, thin, transparent or nearly so, symmetrically 
convolute, carinated by a double row of tubercles,- terminating 
smooth or tuberculated ribs radiating towards the centre; 
aperture large, elongated ; peritreme acute, interrupted by the 
body whorl. — Obs. The exquisitely beautiful, light and delicate 
fabrics included under the above name are inhabited by a mollus- 
cous animal named the Ocythoe, which is provided with tubercu- 
lated arms. These, hanging over the sides of the aperture, give 
to the whole the appearance of a vessel propelled by oars : a 
poetical illusion further heightened by the broad, flat membranes 
of the two arms, which, when vertically expanded, present an idea 
of sails. Pliny has described the Nautilus (the name has been 
changed by the moderns) as sailing gracefully on the Mediter- 
ranean waters ; and Pope has versified the idea in the well known 
lines 

" Learn of the little Nautilus to sail, 

Spread the thin oar and catch the driving gale.'' 

Scientific men have long been engaged in the interesting dis- 
cussion, whether the animal really belongs to the shell in which 
it is found, or whether, having destroyed the rightful owner, it 
has possessed itself of the " frail bark." It is now, however, 
proved beyond the shadow of a doubt that the Agonaut is the 



74 ASIPHONJBRANCHIATA. 

testaceous part of the Ocythbe, and that the broad membranes 
which in some representations have been artificially placed as 
sails, are naturally bent backwards over the shell like the mantle 
of some other molluscs. The interesting experiments of Madame 
Power, in the Mediterranean, have contributed very materially 
to lead the investigations of Naturalists to a satisfactory con- 
clusion. This lady kept a cage under water, in which Argonautse 
were bred in great numbers, giving her an opportunity of tracing 
the gradual development of the shell in all its stages, from the 
elastic and transparent nucleus to the full grown " Paper Sailor." 
Fig. 485. 

ARIANTA. Leach. A sub-genus of land shells, containing Helix 
arbustorum, Auct. (Gray, Turton, p. 137.) 

ARION. A genus of slugs which have no shells. 

ARROW-HEADS. One of the names by which fossils of the genus 
Belemnites were formerly known. 

ARTEMIS. A genus of bivalve shells, distinguished from those of 
the genus Venus, by having a rounded, denticular form, and a 
deep, angular sinus in the palleal impression. This does not 
appear to me to be a sufficient ground of generic distinction, the 
palleal impressions of the Veneres being subject to great varia- 
tions. British, also from West Indies, South America, Australia, 
&c. A. lincta, fig. 118. 

ARTICULATED. (Jointed.) Applied to distinct parts of shells, 
which are fitted or jointed into each other, as the valves of 
Chitones and those of Balani. The operculum of Nerita is said to 
be articulated to the columella, having a small process by which 
it is as it were locked under the edge. See Introduction. The 
word is also applied to the Cirri, which protrude from the oral 
openings of Cirripedes. 

ARTICULINA. D'Orb. A genus of microscopic Foraminifera. 

ASIPHONIBRANCHIATA. Bl. The second order of Paracephalo- 
phora Dioica, Bl. Consisting of spiral univalves, which have no 
notch or canal at the anterior part of the aperture. This order is 
divided into the families Goniosomata, Cricosomata, Ellipsosto- 
mata, Hemicyclostomata, and Oxystomata. 






ASTARTE. JO 

ASPERGILLUM. Lam. (From Jspergo, to sprinkle.) Fam. 
Tubicolse, Lam. Pyloridea, Bl. — Descr. The small, equal, equi- 
lateral valves are cemented into, so as to form part of, a large 
tube ; the umbones are slightly prominent outside. The tube is 
elongated, rather irregular, granulated with sandy particles, and 
terminated at the base by a convex disc, which is perforated by 
small pores, elongated into tubes round the edge, presenting a 
resemblance to the spout of a watering pot, whence the name is 
derived. Loc. New Holland, Java, New Zealand, Red Sea. Fig. 
44. Aspergillum Vaginiferum. 

ASSIMINEA. Leach. Fam. Turbinacea, Lam.— Descr. Inclining 
to oval, light, thin, covered with a horny epidermis, spire pro- 
duced into an acute pyramid ; whorls slightly angulated in the 
centre, rounded beneath ; aperture elliptical, slightly modified by 
the last whorl ; inner lip planed ; outer lip thin ; operculum 
horny, subspiral. Found in brackish water ; one species may be 
procured abundantly on the muddy shores of the Thames, in 
Kent. There are also species from Calcutta, China, Tahiti, and 
Australia. Without comparing the animals, it is difficult to 
distinguish this genus from some species of Littorina. Fig. 
363. A. Grayana. 

ASTACOLUS. Montf. A genus of microscopic Foraminifera. 
Cristellaria Crepidula, Lam. 

ASTARTE J. Sowerby. (Name of a Sidonian Goddess, Ashtaroth in 
Scripture.) Fam. Nymphacea, Lam. Genus Crassina, Lam. — Descr. 
Suborbicular, equivalve, inequilateral, thick, compressed; hinge 
with two solid diverging teeth in the right valve, one tooth and a 
slight posterior elevation in the left ; muscular impressions, two 
in each valve, uniform, united by a simple palleal impression ; 
ligament external. — Obs. This genus differs from Venus, Cythe- 
rsea, &c in not having a posterior sinus in the impression of the 
mantle. The hinge also differs in having but two cardinal teeth. 
Astarte differs from Crassatella in having no internal cartilage in 
the hinge. Some of the species are British, others are from 
America, and one from Sicily. The fossils occur in Crag, Lower 
Oolite, &c. Fig. 110 A. Danmoniensis. 



76 ATTACHED. 

ASTROLEPAS. Klein. Coronula Testudinaria, Auct. Chelo- 
nobia, Leach. Fig. 15. 

ATLANTA. Lesueur. Fam. Pteropoda, Lam. and Bl. — Descr. 
Spiral, convolute, transparent, fragile, compressed, with a broad, 
fimbriated, dorsal keel, and a narrow aperture. This shell, 
which is called " come cfammon vivant," is found in the 
Atlantic. The small Pteropod, figured in Sowerby's Genera as 
Limacina, belongs to this genus. Atlanta Helicialis, fig. 220. 

ATRACTODON. Charlesworth. (Mag. Nat. Hist. 2nd series, Vol. 
1. p. 218.) A genus proposed for the admission of a singular 
fossil shell, found on the beach at Felix-stone, of which the 
following are the characters ; — fusiform, aperture equalling the 
spire in length, terminating anteriorly in a slightly recurved 
canal; columellar lip smooth, curved, thickened posteriorly into 
a blunt tooth ; spire obtuse. — Obs. This shell would be a Fusus 
were it not for the tooth on the posterior extremity of the colu~ 
mellar lip. The only species known is regularly striated in a 
spiral direction, and named A. Elegans. 

ATRYPA, Dalman. A genus of brachiopodous bivalves, dis- 
tinguished by the valves being nearly equal, and the umbones 
not separated by an intermediate area. A. reticulata, fig 302. 

ATTACHED. Shells are attached to marine substances by various 
means ; in some cases by a byssus, or a bunch of tendinous 
fibres passing through an opening between the valves, which gape 
at their margins to admit a free passage, as in the genera Bysso- 
arca and Mytilus. In other cases the byssus is of a more compact 
substance, and passes through a perforation in the shell itself. 
This is the case with many of the brachiopodous shells, in some 
species of which the perforation is in the point of the umbones, 
a specimen of which is represented in the Introduction. This 
species of attachment does not keep the animal motionless, 
although it is confined to a particular spot. Other shells are 
attached by a portion of their own substance, as in Chama, 
Spondylus, Serpula, &c. in which instances, the attached valve is 
motionless, and is termed the under valve. The Pedunculated 
Cirripedes are attached by a tubular tendinous process, called 
a peduncle. 



AURICULACEA. 77 

ATTENUATED. Drawn out, long, thin, tapering, as the extre- 
mities of Ovulum Volva, fig. 442. 
ATYS. Montf. A generic name including those species of Bulla, 
which are described as "convolute, with the last whorl covering 
the rest and hiding the spire, the apex rounded at both ends." 
Bulla Naucum, Auct. fig. 250. 
AURICLE. (A little ear.) See Auriculated. 
AURICULA. Lam. (Dim. from Juris an ear.) Fam. Auriculacea. 
Bl. Colimacea, Lam. — Descr. Oval or oblong, cylindrical or conical; 
aperture long, narrow, generally narrowest in the centre ; rounded 
anteriorly, with two or three strong folds on the inner lip, and 
the outer lip thickened, reflected or denticulated ; spire short, 
obtuse, epidermis horny, brown. — Obs. The above description 
includes the A. coniformis, f. 298. and several other conical spe- 
cies with narrow apertures which formed the genus Melampus, 
Montf. and Conovidus, Lam. The latter author suppressed his 
genus on ascertaining the Conovuli to be land shells. We ex- 
clude, however, the A. Dombeyana, Lam. f. 300. and several 
similar species, which being more rounded, having thin outer lips 
and but one fold on the columella, are described under the generic 
name Chilina, Gray. It appears rather doubtful whether the 
Auriculae are marine or fluviatile, but the animals appear to be 
amphibious. The Auriculae are principally found in Salt Marshes 
of Tropical climates, some small species are found on the Southern 
European Coasts, as far north as Britain and south as Tierra del 
Fuego. The Auriculae formed a part of the genus Voluta of 
Linnaeus, f. 297. A. Judae, f. 298. A. Coniformis. 
AURICULATED. Some bivalve shells, such as Pecten, fig. 171, 
172, have a flat, broad, somewhat triangular appendage on one 
or both sides of the umbones, called an auricle, or little ear. If 
on one side only, they are said to be uni- auriculated ; if on both, 
they are said to be bi-auriculated. 
AURICULACEA. Bl. The second family of the order Pulmobran- 
chiata, thus described ; " shell thick, solid ; aperture more or 
less oval, always large, rounded anteriorly, and contracted by 
teeth or folds on the columella." This family is included in the 



78 AXINUS. 

genus Voluta of Linnaeus, on account of the plaited columellar 
lip, a character by which that heterogeneous assemblage of shells 
is distinguished. It forms part of the family of Colimacea, Lam. 
from which they differ not only in general form, but also in the 
fact of the animals being partly amphibious, always living (accord- 
ing to De Blainville) on the sea shore, and being occasionally 
covered with water for a short time. It contains the genera 
Pedipes, Auricula, Pyramidella. 

AURIFERA. Bl. Otion, Auct. 

AURIFORM. (From Auris, an ear ; forma, shape.) Ex. Haliotis, 
fig. 338. 

AURISCALPIUM. Megerle. Anatina, Lam. 

AVICULA. Lam. (From Avis, a bird). Fam. Malleacea, Lam. 
Margaritacea, BL— Descr. Inequivalve, inequilateral, foliaceous, 
subquadrate, oblique, pearly; hinge rectilinear, lengthened into 
auricular appendages, with a small indistinct tooth in each valve, 
an elongated, marginal, ligamentiferous area, and an hiatus in 
the left valve, for the passage of a byssus ; one circular muscular 
impression, near the centre of each valve, with a series of smaller 
ones arranged in a line towards the umbones. — Obs. The Melea- 
grinse of Lamarck, Margaritiferse, Schum. included in this de- 
scription, consist of the more rounded species, and do not present 
the elegant obliquity of form, nor the wing-like auricles from 
which the genus Avicula receives its name. The Aviculse are 
pearly within. From A. margaritifera, a young specimen of 
which is figured in the plates, fig. 164, is obtained oriental 
pearls- This is an example of Meleagrina. A. Hirundo, fig. 
163, belongs to the genus Avicula of Lamarck. It is, however, 
needless to continue the separation. Aviculse are from E. and 
W. Indies, Mexico, Coasts of the Pacific, Mediterranean, British 
Islands, &c. Fossil species occur in the London clay, &c. 

AXINUS. J. Sowerby. — Descr. Equivalve, transverse ; posterior 
side very short, rounded, with a long ligament, placed in a furrow, 
extending along the whole edge ; anterior side produced, angu- 
lated, truncated, with a flattish lunule near^the beaks. The late 
Mr. James Sowerby, who described this shell in the Mineral 



BALANUS. 79 

Conchology, did not consider his genus as established, not having 
seen the hinge. 

AXIS. The imaginary line, round which the whorls of a spiral 
shell revolve. The extremities of the axis are pointed out in fig. 
379, by the letters, a. a. See "Columella." 

AZECA. Leach. Fam. Colimacea, Lam. —Deser. " Animal like Bu- 
linus, with subcylindrical, rather obtuse shell, covered with a 
polished periostraca (epidermis) ; aperture pear-shaped, curved 
and pointed at the top ; the margin thick, obtuse, united all 
round and toothed ; the axis imperforated." Gray's edition of 
Turton's British Shells, page 189.— Obs. The Turbo Tridens of 
Montagu, upon which this genus is founded, resembles Bulinus 
lubricus in general form and character. Both these shells differ 
from the true Bulini in having the peritreme entire, and in being 
pellucid and glossy. Azeca differs from Bulinus lubricus in 
having three teeth in the aperture, two on the inner lip and one 
on the outer. Not seeing the necessity for creating a genus on 
grounds so slight, I have simply transcribed the description given 
above, leaving others to form their own conclusions as to the pro- 
priety of separating this shell from the genus Bulinus. Britain, 
Central and Southern Europe. Azeca Tridens, fig. 290. 

AZEMUS. Ranzani. Conia, Leach. 

BACULITES. Lam. Fam. Orthocerata, Bl. Ammonacea, Lam. — 
JDescr. Straight, conical, tubular, laterally compressed ; chambers 
divided by very sinuous lobed septa, the last elongated ; aperture 
elliptical; siphon dorsal. — Obs. This genus differs from Ortho- 
ceras in the same manner in which Ammonites differs from Nau- 
tilus, having its septa sinuated and branched. A Baculite might 
be described as a straight Ammonite. This genus is known only in 
a fossil state. It is found in the Cretaceous Limestone of Maa- 
stricht and Valognes. Fig. 484. B. Faujasii. 

BALANUS. Brug. (an Acorn ; " gland de Mer." Fr.) Order 
Sessile Cirripedes, Lam. Fam. Balanidea, BL— Descr. Shell com- 
posed of six valves articulated to each other side by side in a circle, 
by the insertion of lamina ; closed at the base by a flat, cylin- 
drical or cup-shaped valve, by which it is generally attached ; and 



80 BALEA* 

at the apex by a conical operculum, consisting of four valves in 
anterior and posterior pairs. Each valve of the shell is divided 
into a rough triangular portion pointed towards the apex, and a 
flat area on each side. — Obs. This description includes the Acasta 
of Leach, which growing in sponges, has the base cup-shaped ; 
Conoplcea of Say, which being attached to the stems of Gorgonia 
and sea-weeds has the base elongated and lanceolate, and Chirona, 
Gray. Balanus is the only genus of Sessile Cirripedes the shells 
of which consist of six parietal valves, except coronula, which has 
no shelly base, is flatter, and has the valves of the operculum 
placed horizontally. The Balani are common in all seas, ad- 
hering to rocks, corals, floating timber, and to each other. The 
fossil species are found in the newest strata, at Bordeaux, Paris, 
&c. Fig. 25. B. Tintinnabulum; 26. Acasta Montagui ; 27. Balanus 
galeatus, Conoplcea, Say. 

BALANIDEA. Bl. The second family of the class Nematopoda, 
Bl. corresponding with Sessile Cirripedes, Lam., and consisting of 
Coronular Multivalves, which are fixed, and in a manner soldered 
to submarine substances, by the base of the shell ; as distinguished 
from the Lepadicea, Bl., Pedunculated Cirripedes, Lam., which are 
attached by a fleshy stalk. The Balanidea are composed of two 
sets of valves, besides the shelly plate or base on which they rest. 
The first, called the Parietal valves, are arranged so as to surround 
the body of the animal ; the second, called the Opercular valves, 
are placed horizontally, so as to cover the aperture. 

BALEA. Gray. Fam. Colimacea, Lam. — Descr. Spiral, turrited, 
concentrically striated, sinistral, and covered with a thin brown 
epidermis ; spire composed of numerous whorls, gradually in- 
creasing in size ; aperture small, sub-quadrate ; peritreme entire, 
slightly thickened, with a very slight fold on the columella ; axis 
perforated. — Obs. A genus of small land shells, found in moss at 
the roots of trees in Britain, not very nearly resembling any other 
land shells, except Clausilia, from which they differ in not having 
the clausium. They have been placed in Helix by De Ferrusac, 
and in Pupa by Draparnaud. B. fragilis, fig. 296. Helix perversa, 
Fer. Pupa perversa, Drap. 



BELLEROPHON 81 

BARBATA Humphrey. Unio. Lam. 

BARNACLES. Pentelasmis, Auct. (fig. 34.) Called Anatifa, 
by Linnaeus and Lamarck, from the ancient notion that they were 
the eggs or embryo of the Barnacle Duck. See Anatifer. 

BASE. In all shells which are attached to sub-marine substances, 
the base is that part of the shell which forms the point of attach- 
ment—as for instance, the attached valve of Spondylus, the basal 
plate of Balanus, the lower part of the peduncle of Pentelasmis ; 
in Unattached Bivalves, the margin opposite to the umbones, 
where the foot of the animal, or the part analogous to it, pro- 
trudes ; in spiral univalves, the aperture, which rests on the back 
of the animal when walking. Lamarck and some other authors 
have used the term base as simply opposed to apex, and apply 
it to the anterior of the aperture. 

BATOLITES. Montf. Hippurites, Auct. 

BEAK. The Apices, or points of the valves of a bivalve shell, gene- 
rally termed Umbones, in descriptions. Also any part which is 
rostrated or drawn out like a beak. 

BEAKED. See Beak and Rostrated. 

BEAR'S-PAW-CLAM. The common name for Hippopus maculatus, 
a representation of which is given in the plates, fig. 156. 

BELEMNITES. Auct (BeXsfivov, belemnon, a dart, or arrow.) 
Fam. Orthocerata, Bl. and Lam. — Descr. Straight, conical, con- 
sisting of two parts; the external portion forming a thick solid 
sheath, with a cavity at the base to admit the internal portion or 
nucleus, which is mathematically conical, and is divided into 
chambers by smooth simple septa perforated by a lateral siphon. — 
Obs. These singular fossils, which are found in most secondary 
beds, have long attracted the attention of philosophers as well 
as of the ignorant, from whom they have received the various 
appellations of Thunder-Stones, Petrified Arrows, Petrified Fingers, 
Devil's Fingers, Spectre Candles, &c. The above description is 
framed to include the genera Hibolithes, Porodragus, Cetocis, 
Acamas, and Paclites of De Montfort, and Actinocamax, Stokes. 
Fig. 466 to 468. 

BELLEROPHON. Montf. (or Belleroph'us). —Descr. Convolute, 

G 



82 BTLABIATED. 

symmetrical, umbilicated, with a double dorsal ridge ; aperture 
wide, semilunar. — Obs. The fossils composing this genus re- 
semble Nautilus in general appearance, but not being chambered 
shells they approach very near to Argonauta, from which they 
diifer only in the thickness of their shell and in roundness of 
their external form. This genus is erroneously placed by De 
Montfort among chambered shells, and by De Blainville next to 
Bulla. It belongs to the Monothalamous Cephalopoda of La- 
marck. This fossil is found principally in the Carboniferous 
Limestone. Fig. 486, 487, represent B. tenuifasciata. 
BELOPTERA. The bony support of a species of Cuttlefish, partly 

resembling Sepia. 
BIAPHOLIUS. Leach. A genus believed tobe identical with Hiatella. 
BI-AURICULATED. Having two auricles placed at the sides of 

the umbones, as in Pecten, fig. 171. See Auriculated. 
BICATILLUS. Sw. A sub-genus of " Calyptrsedse," including 
those species, which have cup- shaped internal septa, as for ex' 
ample, Calyptrsea extinctorium, fig. 235. 
BICONIA. Sw. A sub-genus of " Calyptrsedee," including those 

species in which the septum is partly spiral. 
BIFID. Divided, double. 

BIFRONTIA. Deshayes. Also Omalaxis, Desh. Fam Turbina- 
cea, Lam.— Bescr. Discoidal, planorbicular, with whorls sometimes 
not contiguous ; umbilicus deep, keeled at the margin ; aperture 
subtriangular, somewhat dilated ; outer lip acute, separated by a 
deep notch at both extremities. — Obs. We do not see any reason 
for separating this genus from Solarium, except the last men- 
tioned character. The few fossil species which this genus con- 
tains (Solarium disjunctum, Bifrons, &c.) are found principally 
in the Paris basin. Fig. 354. Solarium Bifrons. 
BI -FURCATE. Double pronged, or having two points. Ex. the 

internal appendage of Calyptrsea Equestris, fig. 234. 
BIGENERINA. D'Orb. A genus of microscopic Foraminifera. 
BILABIATED. Having the edge of the outer lip as it were 
doubled, by one part of the lip being more thickened and reflected 
than the other, so as to form a ledge, or second lip. 



BOAtl's TUSK. 83 

BILOBATE. Having two prominent parts, as the outer lip of 
Rostellaria Pes-Peleeani, fig. 404. 

BIPARTITE. Composed of or divided into two parts ; double ; as 
the valves of Platylepas, fig. 19, each of which has a septiform 
division in the centre ; also the area on the hinge of Spondylus. 
See Frontispiece. 

BIROSTRA. Sw. A genus composed of species of Ovulum, 
which have elongated extremities, as, for instance, Ovulum Volva, 
fig. 442. 

BIROSTRITES. Lam. (Double Beak.) A fossil formerly con- 
sidered as a distinct bivalve shell, with conical umbones, and 
placed in the family of Rudistes by Lamarck, but now known to 
be an internal cast of Sphserulites, fig. 196. 

BISIPHYTES, Described by De Montfort as resembling a Nautilus, 
but having two distinct siphons. As no such fossil species is now 
known to Naturalists, it appears probable that De Montfort 
having a specimen of some Nautilus, with an accidental depression, 
took it for a second siphon. 

BITHINIA. Gray. A genus described as differing from Paludina, 
in having the operculum shelly, and the mouth of the shell 
thickened internally. Paludina impura, Auct. Fig. 537. 

BITOMUS. Montf. A microscopic shell, deriving this general 
appellation, from the appearance of a double aperture. 

BIVALVE. A shell composed of two equal, or nearly equal principal 
parts, each part having a separate nucleus, turning upon each 
other by means of a hinge. The class Conchifera of Lamarck, 
Acephalophora of De Blainville severally include the whole of 
the bivalve shells ; the latter name being derived from the fact 
that the animals have not distinct heads, and neither eyes nor 
tentacula. All bivalve shells are marine or fresh-water. They 
form the class Dithyra of Aristotle. It may be observed that 
some of the Acephalophora, the Pholades, for example, have small 
testaceous pieces fixed on the hinge, which are called accessary 
valves. These are still fairly bivalve shells, although the genus 
* Pholas has been placed by some writers among the multivalves. 

BOAR'S TUSK. A common name given to shells of the genus 

g 2 



84 



BORER, 



Dentalium. One particular species has received a specific name 
in accordance with a supposed resemblance, namely, Dentalium 
Aprinum, (of a Boar.) 

BONELLIA. Desh. A genus formed, in the first instance, for 
the reception of Bulinus terebellatus, Lam. which Mr. G. B. 
Sowerby, in his Genera of Shells, united with the genus Pyra- 
midella. M. Deshayes, however, in his new edition of Lamarck, 
makes the genus Bonellia include several species which I have 
arranged in the genus Eulima. From the remarks of M. Deshayes, 
torn. 8, p. 286, 287, we are led to suppose that the estimated 
difference between Eulima and Bonellia consists in the latter 
having the axis perforated ; or in other words, umbilicated. 
After remarking " que Mr. Sowerby, junr. confond deux choses 
bien distinctes, sous le nomme d'Eulima," M. Deshayes gives the 
following description of his genus, (translated) " shell turri- 
culated, smooth, polished, with the apex acute and laterally 
inclined ; axis perforated throughout its length ; aperture small, 
entire, angular at the extremities ; columella simple and without 
folds ; outer lip thin, simple, nearly parallel with the longitudinal 
axis." That author further remarks, " Mr. Sowerby, junr. a 
signale cinque especes vivant, que nous rapportons a notre genre." 
(Sowerby, junr. Conchological Illustrations, parts 52 and 53 ; 
50, Great Russell Street, Bloomsbury.) The species thus selected 
are E. splendidula, E. marmorata, E interrupta, E. imbricata, 
E. brunnea ; the two last of which have the umbilicus so incon- 
siderable, as to be scarcely distinguishable from other species, 
which M. Deshayes has left in the genus Eulima, and which 
have a slight hollow, almost approaching to a perforation, behind 
the columella. Eulima marmorata, (Bonellia, Desh.) is figured 
in the plates, fig. 348. 

BODY WHORL. The last whorl, constituting the bulk of the shell. 

BORELIS. Montf. Melonia, Bl. A genus of microscopic 
Foraminifera. 

BORER or PIERCER. A term applied to those species of Acepha- 
lopodous Mollusca, which bore holes as dwellings in the rocks, 
as the Pholades, and some others. 



BRACHIOPODA. 85 

BRACHIOPODA. Lam. A family of symmetrical bivalves be- 
longing to the third section of Lamarck's order " Conchifera 
Monomyaria," described as bivalve (generally symmetrical) ad- 
hering to marine bodies, by a tendon passing through the shell, 
having no true ligament. What most distinguishes this family and 
renders it remarkable is the structure of the animal. It has two 
elongated, tendril-shaped arms. When the animal is in a state of 
repose these arms are coiled up spirally and enclosed in the shell, 
but when required for use, are unfolded and extended, This 
family contains the genera Orbicula, Terebratula and Lingula, in 
the system of Lamarck, to which may be added Thecidium, Pro- 
ductus, Spirifer, Magas, Pentamerus, Crania, Strigocephalus, 
Strophomena, and some others enumerated in the explanation 
of figures 201 to 219. The above genera may be thus dis- 
tinguished. 

1. Orbicula. Umbones central ; byssus passing through a 

hole in the flat valve. Fig. 201. 

2. Atrypa. Without foramen or space between the valves. 
Fig. 203. 

3. Producta. The same, valves produced, overwrapping ; 

including Leptsena. Fig. 206, 206*. 

4. Terebratula. Hinge of the upper valve produced be- 

yond that of the other, with a pit or foramen ; including 
Delthyris, Orthis, Trigonosemus y Magas, Strophomena. Fig. 
202, 205, 207, 208, 209. 

5. Spirifer. The same, with deep triangular area ; spiral 
folds in the interior ; including Trigonotreta and Cyrtia. 
Fig. 204, 214, 215. 

6. Thecidium. Large valve attached ; curved ridges in 

the inner surface ; two jutting points or teeth on the hinge. 
Fig. 216. 

7. Crania. Attached by the surface of the valve ; muscular 
impressions four, forming a face. Fig. 197, «, b. 

8. Pycnodonta. Irregular; hinge with raised pointed teeth. 

Fig. 217, 218. 



86 BUCCINUM. 

9. Pentamerus. Valves divided by septa ; including Gy- 

pidia. Fig. 210 to 213. 
10. Lingula. Valves equal, gaping, with a peduncle. 
Fig. 219. 

BRACHITOMA. Swainson. A genus composed of Pleurotoma 
strombiformis and similar species, described as " sub-fusiform ; 
resembling a small Strombus or Fusus ; spire and aperture of 
equal length ; canal short ; outer lip slightly ascending, and 
forming a short canal ; sinus very small and nearly semi- 
circular; inner lip thickened above. B. Strombiformis, Sow. 
Man. fig. 381." Europe, East and West Indies, China, &c. 

BRANCHIFERA. Bl. The second family of the order Cervico- 
branchiata, containing the following genera of symmetrical uni- 
valves : — Fissurella, Emarginula, and Parmophorus. 

BRISMiEUS. Leach. Order. Pedunculated Cirripedes. Lam. 
— Descr. Seven plates, three pairs lateral, one dorsal ; form 
cylindrically conical ; pedicle not described. Hab. Holes in 
corals. B. Rhophodius, fig. 38. — Obs. This minute shell most 
nearly resembles Pollicipes Mitellus, fig. 37*> but the difference 
may be seen at once by comparing the figures. 

BRONTES. Montf. This generic name is given to such species 
of Murex as have a very long, closed canal ; with a short spire> 
circular aperture, and are destitute of spires and ramifications. 
Brontes (Murex) Haustellum, fig. 396. 

BUCARDIA. Schum. Isocardia, Auct. 

BUCCINUM. Linn. Fam. Purpurifera, Lam. Entomostomata, 
Bl. — Descr. Subovate or oblong, covered with an epidermis; 
spire turrited, consisting of few whorls ; aperture wide, subovate, 
terminating anteriorly in a very short canal, reflected over the 
back ; outer lip simple, slightly reflected ; inner lip spread over 
a portion of the body whorl, terminating in a thick, smooth 
columella ; operculum horny. Hab. British Seas, Northern 
Ocean, and Coast of Africa. Most of the fossil species occur in 
Crag, some in upper marine formation and London clay.— Obs. 
There are considerable difficulties in keeping this genus distinct 



BULINUS. 87 

from others nearly related to it, into which many of the species 
run by imperceptible gradations. The genus Nassa has been 
separated on account of the little notch, which terminates the 
columella. Some species of Terebra come so close upon the 
Buccina, that it is difficult to say where one genus ends and the 
other begins. T. Buccinoides, fig. 427. Buccinum Undatum, 
the common Whelk, fig. 421. 
BUFO. Montf. A generic division of the species composing Ra- 
nella, characterized as having the shell not umbilicated. Ex. R. 
ranina, fig. 394. The above character is scarcely sufficient in 
some cases, even as a specific distinction. 
BULBUS. Humph. Rapella, Swainson. A genus formed for 
the reception of Pyrula papyracea, Auct. (fig. 389), and similar 
species. Rapantjs, Montf. 
BULIMIMA. Montf. A genus of microscopic Foraminifera. 
BULIMULUS. Leach. Fam Colimacea, Lam. The author is 
unacquainted with the characters by which the two or three 
species included in this genus are to be distinguished from Bu- 
linus. We have represented, fig. 283, Bulimulus trifasciatus, 
Leach, (Bulinus Guadaloupensis, Auct.) This occurs in the same 
limestone which encloses the half fossilized human remains from 
the Grand Terre of Guadaloup. Several species are described by 
the Rev. L. Guilding in the Zoological Journal, namely, the B. 
Undulatus, Antiguensis, and Proteus ; but neither from the shells 
themselves, nor from the figures of the animal, can we draw any 
information as to the generic character ; the difference alleged by 
Mr. Swainson and Mr. Gray being a comparative thinness in the 
outer lip. 
BULINUS. Brug. (Bulinus, Lam.) Fam. Colimacea, Lam. Li- 
maciuea, Bl. — Bescr. Oval or oblong, light, covered with a thin 
epidermis ; spire obtuse, variable in length and in the number of 
whorls, which are generally few ; aperture wide, oval, rounded 
anteriorly ; outer lip simple, usually reflected, joining the colu- 
mella without a sinus ; inner lip reflected over part of the body- 
whorl. The Bulini are land shells, found in many parts of the 
world.— Obs. The genus Bulinus can only be distinguished from 



88 



BULLIA. 



Helix by its oval form ; it forms part of the genus Helix of De 
Ferrusac, under the sub-generic designation of Cochlostyla. It 
is known from Achatina by the absence of the notch at the point 
of union between the inner and the outer lips. The young are 
produced from eggs, which are as firm and opaque as those of 
birds. (See Introduction.) Bulinus rosaceus, fig. 282. B. Guada- 
loupensis, fig. 283. B. Lionetianus, fig. 284. B. lubricus, fig. 
285 . Many new species were brought to this country by Mr. 
Cuming, and are represented in the Conchological Illustrations, 
published by the Author at 50, Great Russell Street, Bloomsbury, 
(in parts 21,22, 23, 26, 27, 30, 31, 34, 35, 137 to 146, 185, 186.) 
Species occur in Europe, West Indies, Brazil, and South America 
generally. Some small species are British. 

BULLA. Auct. Fam. " Bulleens," Lam. Akera, Bl.— Descr. Gene- 
rally thin, smooth, oval, oblong or cylindrical, more or less convo- 
lute ; spire short, depressed, or hidden by the last whorl ; aperture 
long, wide in front, gradually narrowing towards the spire ; outer 
lip thin ; inner lip spread over a part of the last whorl. — Obs. 
The shells composing this genus are very variable in form. The 
light horny species with an elastic lip is called Akera, fig. 247. 
The more decidedly convolute species with hidden spires are the 
Atys, Montf. B. Naucum, fig. 250. B. Lignaria, fig. 251, is Sca- 
phander of Leach. The light, thin species, with extremely wide 
aperture, fig. 248, is Bullaea aperta, Lam. The genus Bullinula of 
Dr. Beck, consists of those species which have more produced 
spines, fig. 253. The Bullae are marine, and inhabit all climates. 
The fossil species occur in tertiary beds. 

BULLiEA. Lam. Bulla aperta, Auct. fig. 248. 

BULLAE ANA. (" Bulleens, Lam.") A family belonging to the first 
section of Lamarck's order, Gasteropoda, containing the genus 
Bulla. The genera Bullaea, Akera, Aplustra, Atys, Scaphander, 
Bullinula, into which it has been divided, may all be fairly included 
under the name Bulla. 

BULLIA. Gray. A genus of shells partly resembling Buccinum, 
and Terebra in general form, being more elongated than the 
former and more ventricose than the latter. Mr. Gray remarks 



CALCAR. 89 

in the Synopsis of the British Museum, page 114, that the Bulliae 
resemble the Nassse in most characters, u but they have a very 
large, broad foot, and the hinder part of the inner lip of the shell 
being extended beyond the mouth, forms a raised enamelled band 
round the suture of the whorls, as is also the case with the Ancil- 
lariae and some Volutes." Bullia vittata, fig. 427, is an example 
of the genus. The name Subula is given by De Blainville to the 
other species of Terebra, so that if both these genera were ad- 
mitted, the old genus Terebra must be expunged. 

BULLINULA. Beck. Species of Bulla, with produced conical 
spires, fig. 253. 

BYSSOARCA. Sw. (Byssus and Area.) Fam. Arcacea, Lam. A 
genus of bivalve shells, composed of the Area Now, and several 
other species, separated from the genus Area on account of their 
shells being attached by means of a byssus passing through an 
hiatus in the ventral margins. B. Now, fig. 132. The species 
occur in Southern Europe, East and West Indies, China; also, 
on the coasts of Great Britain. 

BYSSOMYA. Cuvier. ( Byssus and Mya.) De Blainville states that 
although the shell of this proposed genus resembles Saxicava, 
the animal is sufficiently different to justify the separation. 

BYSSUS. (Bvavog, byssus, ancient name for linen.) The ten- 
dinous fibres by which some Bivalves are as it were anchored or 
moored to sub -marine substances. A fine example of this is to 
be seen in the Pinnse which bear some resemblance to large 
Muscle Shells and have an hiatus in the margins of the valves 
through which a bunch of silken fibres passes. In the British 
Museum there is preserved a pair of gloves which have been 
woven of these fibres. The Byssus is peculiar to some bivalve 
shells such as Muscles, Hammer Oysters, Area Nose, &c. 

CALCAR. Montf. (a spur.) A genus composed of Trochus 
stellaris, Lam. and other depressed species of Trochus which 
are characterized by a stellated keel round the angle of the last 
whorl ; but not including T. Imperialis, which is the genus Impe- 
rator, Montf. The difference consists in the latter being umbili- 
cated and the former not. T. stellaris, fig. 358. 



90 CALLITHEA. 

CALCAREOUS, {calx, lime.) A term applied to a shell or to its oper- 
culum which is composed principally of lime or shelly matter, as is 
usually the case, in distinction from one which is of an horny, mem- 
branaceous texture. The greater number of shells are calcareous, 
but it forms an important point of distinction with regard to the 
operculum. The only difference between the genera Trochus and 
Turbo, as at present established, depends upon the calcareous 
or shelly, and the corneus or horny texture of the operculum. 

CALCEOLA. Fam. Rudistes, Lam. and Bl. — Bescr. Equilateral, 
inequivalve, triangular ; umbones separated by a large triangular 
disc in the lower valve ; cardinal margin straight, linear, dentated ; 
lower valve large, deep; upper valve flat, semi- orbicular, forming 
a kind of operculum to the lower. — Obs. This singular shell, 
known only in a fossil state, in the Palaeozoic beds, is placed by 
Linnaeus in the genus Anomia. Lamarck places it among his 
Rudistes, but Mr. Sowerby in his genera of Shells, states that it 
should be added to the family of Brachiopoda Fig. 194, 195. 
C. Sandalina. 

CALLANTICA. Gray. Pollicipes hispidus, Leach. 

CALLIA. Gray? A genus described as having a peculiarly polished 
shell like Pupina, but wanting the notch. 

CALLISOSTOMA. Sw. A genus of shells separated from Trochus, 
and thus described, " Imperforate ; spire elevated, acute ; aper- 
ture broader than high, transversely ovate, hardly sinuated at the 
base, and slightly oblique ; shells always smooth, and often po- 
lished." C. zizyphina is mentioned as an example. 

CALLIRHOE. Montf. p. 362, vol. 2. Appears to be figured from 
the nut or inner portion of a large Belemnite. 

CALL1SCAPHA. Gray? Iridina Nilotica, Sow. Zool. Journ. 1. 
pi. 2. Separated from Iridina on account of the hinge margin 
being smooth. 

CALLITHEA. Sw. A sub-genus of Mitrae, consisting of those 
species, which like M. sanguisuga, have the " spire and aperture 
of nearly equal length ; internal channel nearly obsolete ; shell 
with longitudinal linear ribs, crossed by transverse striae and 
bands ; base contracted." Swainson Mallac. Lard. Cyclop. 



CALYPTR^EA. 91 

CALLOSITY. A term used in general zoology to express those hard 
horny tumidities formed in the skin of some animals, (such as 
the Dromedary, for instance) in those parts which are most fre- 
quently used. It is not used in this sense by Conchologists, who 
apply it to those undefined tumidities or bumps which appear on 
the inner surface and hinge of some bivalve shells, and to the 
thickening over the umbilicus of Naticse. Glycimeris, fig. 67. 
Natica, fig. 327, 328. 

CALPURNUS. Montf. Ovulum verrucosam, Auct. Distinguished 
by the small circular tubercle at the back of each extremity 
of the shell. Fig. 441. 

CALYPTRACEA. Lam. A family belonging to the first section of 
the order Gasteropoda, Lam., the shells of which are described 
as always external, covering the animal, and having no oper- 
culum. The genera contained in this family may be thus distin- 
guished. 

1. Calyptr^a. Conical; apex central, septum spiral, cup- 

shaped, or forked; including Infundibulum. Fig. 234 to 238. 

2. Crepidula. Apex terminal; septum flat, reaching half 

across the aperture. Fig, 239. 

3. Capulus. Conical ; apex obliquely curved, no septum. 

Fig. 240. 

4. .Emarginula. Apex curved backwards ; a notch in the 

anterior margin ; including Parmophorus. Fig. 241, 242. 

5. Cemoria. A slit near the apex. Fig. 244. 

6. Fissurella. A slit upon the apex. fc Fig. 245. 

7. Rimula. A slit near the margin. Fig. 243. 

8. Ancylus. Apex curved sidewise. Fig. 246. 
CALYPTRACEA. Bl. The second family of the order Scutibran^ 

chiata. Bl. thus described: "Shell more or less conical, not 
spiral, or very slightly so ; aperture large and entire." The ge- 
nera included in this family are Crepidula, Calyptrsea, Capulus, 
Hipponyx, and Notrema. 
CALYPTRiEA. Lam. Fam. Calyptracea, Lam. and BL— Descr. 
Conical, patelliform, irregular, with an internal, lateral, salient 
plate or septum, varying in form. — Obs. The internal appendage 



1)2 CANALIFERA. 

is in some species cup-shaped, in some it juts out of the centre in 
a double point ; in others it is only a small flap ; and in others 
a spiral disc. These last, which are shaped like Trochus, are 
separated by De Montfort under the appellation Infundibulum ; 
Trochatella, Sw. The Calyptrsea may be known from Crepi- 
dula by the septum, which in the latter is a flat plate reaching 
half way across the cavity. Fig. 234, 5, 6. 

CAMERINA. Brug. Nummulites, Auct. 

CAMILLUS. Montf. A genus founded upon a minute spiral 
shell, with a triangular aperture, turned over the back of the 
last whorl. It is figured in Soldani's Testacea Microscopica. 

CAMPULOTUS. Guettard. Magilus, Auct. 

CANAL. A" groove which characterizes some spiral univalves, 
where the inner and outer lips unite at the front part of the aper- 
ture. This canal is drawn out in some shells to a considerable 
length , in others it is turned abruptly over the back. The family 
Canaliferae, Lam. (fig. 372 to 401), are all provided with this 
canal. 

CANALICULATED. Applied generally to any distinct groove or 
canal. 

CANALIFERA. (Canaliferes, Lam.) A family belonging to the 
order Trachelipoda, Lam. nearly corresponding with the family 
Entomostomata in De Blainville's system, and described as having 
a canal of greater or less extent at the anterior part of the aper- 
ture. This canal is sometimes straight, sometimes tortuous, and 
in some genera it is recurved over the back of the shell. All the 
shells have an operculum, and the thickness of the perfectly 
formed outer lip does not increase with age. The Canalifera are 
characterized by having a canal, in distinction from the Pur- 
purifera, which have only a notch. This family contains the 
following genera, 

1. Cerithium. Club-shaped. Fig 372. 

2. Potamis. The same, fresh water. Fig. 377. 

3. Nerinea. The same, with internal folds. Fig. 374. 

4. Trip,hora. Anterior and posterior canals closed so as 
to present three openings. Fig. 375, 376. 



CANCELLARIA 93 

5. Telescopium Pyramidal, trochiform. Fig. 3/8. 

6. Pleurotoma. A slit on the upper part of the outer lip; 
including Clavatula. Fig. 379, 381. 

7. Tu rbi nell a. Three horizontal folds on the columella, 
Fig. 382, 383 

8. Spirillus. Spire papillary; one fold on the columella, 
Fig. 384. 

9. Cancellaria. Three folds, and internal costse. Fig, 

385. 

10. Fasciolaria. Oblique folds, the lowest the largest. 

Fig. 386. 

11. Fusus. Fusiform ; no folds on the columella. Fig. 387, 

12. Pyrula. Pear-shaped. Fig. 388 to 390. 

13. Struthiolaria. Outer lip thickened ; sinuated. Fig, 

391. 

14. Ranella. Two rows of varices; a canal at each extre- 
mity of the aperture. Fig. 393, 394 . 

15. Murex. Three or more rows of varices; only one distinct 
canal. Fig. 395, 396. 

16. Typhis. A tubular perforation between each varix. Fig. 
397. 

17. Triton. Varices not in rows. Fig. 398 to 401. 
CANCELLARIA. Auct. (From Cancellatus, cross-barred, like win- 
dow frames or net work.) Fam. Canalifera, Lam. Entomosto- 
mata, Bl. — Bescr. Oval, thick, cancellated; spire generally short, 
pointed ; aperture sub-ovate, emarginated anteriorly, pointed at 
the posterior extremity ; outer lip marked within by transverse 
ridges ; inner lip spread over part of the body whorl, terminating 
in a straight, thick, obtuse columella, with several strong oblique 
folds Hah. Indian Ocean, Coast of Africa, America, and West 
Indies. Fossils found in London Clay and Calc-grossier of Paris. 
Differing from Turbinellus in form and in the transversely ribbed 
inside of the outer lip. Fig. 315. C. reticulata. — Obs. The latest 
enumeration of the species of this genus is contained in a cata- 
logue published by Mr. G. B. Sowerby, senior, accompanying the 
author's figures of the new species, amounting to 38, in parts 9 to 



94 CAPRELLA. 

13 of the Conchological Illustrations. The greater part of these 
new species were brought to this country by Mr. Cuming. 

CANCELLATED. (From Cancellatus> cross-barred) Applied gene- 
rally to any shells which are marked by ridges crossing each other 
as Cancellaria, fig. 385. 

CANCILLA. Sw. A sub-genus of Mitrae, described as having "the 
whorls crossed by transverse linear ribs ; inner canal wanting, 
plates very oblique ; form slender ; outer lip thin." Ex. M. 
Isabella, M. sulcata. 

CANCRIS. Montf. Crepidulina, Bl. A genus of microscopic 
Foraminifera. 

CANOPUS. Montf. A genus of microscopic Foraminifera. 

CANTHAPLEURA. Guild. A genus composed of those species 
of Chiton, which have the mantle rough, with moveable spines, 
prickles, or hairs. Ex. C. spinosus, fig. 227. 

CANTHARIDUS. Montf. Trochus Iris, Auct. and analogous 
species. Elenchus, Humph. 

CANTHARUS. Montf. A genus of microscopic Foraminifera. 

CANTHIDOMUS. Sw. A sub-genus of Melanopsis, thus described : 
" spire generally short; whorls coronated with spines, or 
marked with longitudinal ribs; base obtuse. C. costata, Sow. Gen. 
f. 3." Melanopsis costata, plates, fig. 315. 

CANTHORB1S. Sw. A sub-genus of the sub-family Trochinee, Sw. 
Described as being " nearly disc- shaped : spire but slightly 
raised; the margin of the body-whorl flattened, and serrated 
with flat spines ; inner lip united to the outer ; pillar and aper- 
ture as in the last. (Tubicanthus) C. imperialis. Mart. 173. f. 
1 714." This sub-genus appears to include those species of which 
De Montfort's genera Imperator and Calcar are formed. 

CANTHROPES. Montf. Described as resembling a Nautilus, 
with the whorls increasing so gradually, that the dorsal edge 
of the aperture advances but little beyond the last whorl. 
This genus is not mentioned by Blainville or Lamarck. 

CAPITULUM. Klein. Pollicipes Mitellus, Lam. fig. 37*. 

CAPRELLA. ? Plekocheilus, Guild. Auricula Caprella, 

Lam. 



CARDIACEA. 95 

CAPRINA. D'Orb. Diceras. Auct. ? 

CAPRINUS. Montf. (Conch. Syst. t. 2. p. 143.) The figure 
appears to be intended to represent Helix Nux-denticulata. 

CAPSA. Brug. Fam. Nymphacea, Lam. — Descr. Equivalve trans- 
verse, subequilateral, subtrigonal; cardinal teeth, two in one 
valve, one notched in the other ; lateral teeth remote, obsolete ; 
an external ligament; two muscular impressions in each valve ; a 
large sinus in the muscular impression of the mantle. — Obs. 
This genus is so nearly related to Donax, that it is difficult to 
distinguish it at first sight. The Capsse, however, have not the 
short, plain, straight, posterior side, the distinct lateral teeth, 
nor the crenulated margins which characterize nearly all the 
Donaces. They are found in the British Channel, Brazil, and 
coast of Pacific Ocean. They are known from Erycina by not 
having the pit in the hinge for the ligament. Fig. 109. C. Brazi- 
liensis. 

CAPULUS. Montf. Fam. Calyptracea, Lam.— Descr. Obliquely 
conical, posteriorly recurved ; apex pointed, sub-spiral ; aperture 
large, rounded, oval ; with two muscular impressions, lateral, 
meeting behind ; epidermis horny, rather velvetty. Britain, 
Mediterranean, West Indies, California, Australia. 

CARDIACEA. (Cardiacees, Lam.) A family of the order Conchi- 
fera Dimyaria, Lam. Most of the genera of shells contained in 
this family are included in the very extensive family of Conchacea, 
in the system of De Blainville. They are described as having 
irregularly formed cardinal teeth, generally accompanied by one 
or two elongated lateral teeth. Most of the species are ventricose, 
and have regular radiating ribs. This family contains the genera 
Cardium, Cardita, Cypricardia, Hiatella, Isocardia, and others 
enumerated in the explanation of figures 122 to 130. Their 
characters may be thus explained. 

1. Cardium. Two cardinal and two lateral teeth in each 

valve, including Hemicardium, Papyridea and Aphrodita, 
in the last of which the teeth are nearly obsolete. Fig. 
122, 123, 123*, 123**. 

2. Venericardia. Two oblique cardinal teeth, one elon- 



96 CARDINAL TEETH. 

gated ; including Cardita, which has the umbones nearly 
terminal. Pachymya may probably be included, but the 
hinge is not known. Fig. 121, 124, and 130. 

3. Hippopodium. One elongated cardinal tooth. Fig. 129. 

4. Megalodon. Hinge broad, septiform, with a large tooth 
in the centre of one valve. Fig. 127. 

5. Isocardia. Teeth laminar ; umbones spiral. Fig. 126. 

6. Cardilia. The same, with a septiform posterior laminar 
tooth. 

7. Hippagus. Shaped like Isocardia, without teeth. Fig. 

128. 

CARDILIA. Desh. Fam. Cardiacea, Lam A genus formed for 
the reception of Isocardia semi-sulcata, Lam. and a small fossil 
shell, which Deshayes had formerly named Hemi-cyclonosta 
Michelini; thus described, (translation) " shell oval, oblong, 
longitudinal, white, heart-shaped, ventricose, with large promi- 
nent umbones ; hinge with a small cardinal tooth and a pit at 
the side; a spoon-shaped projection for the reception of the 
internal ligament ; anterior muscular impression rounded, not 
deep ; the posterior being upon a thin, horizontal lamina, pro- 
jecting in the anterior." Deshayes further remarks that although 
the animal is unknown, the relations of the genus may be 
established by means of the shell alone. Two families contain all 
the shells which have the internal ligament inserted in a spoon - 
shaped projection ; in the one, that of the Anatinse, the ligament 
is supported upon a little bone, which is not soldered to the 
hinge ; in the other, that of the Mactraceee, this little bone has 
no existence. In the former, all the shells are inequivalve ; in 
the latter equivalve. And M. Deshayes, considering that the 
valves are equal, and that there is no separate bone to the 
hinge, is of opinion that the genus ought to be placed near the 
Lutrarise, and not far from the Anatinse. C. semisulcata, fig. 
501, 2. " 

CARDINAL MARGIN. The edge of a bivalve shell on which 
the teeth is placed. 

CARDINAL TEETH. The teeth upon the hinge directly beneath 



CARDIUM. 97 

the umbones of a bivalve shell, as distinguished from the 
lateral teeth, which are placed at a distance on each side. 
In Venus, fig. 119, the cardinal teeth, are marked by the 
letter c. 

CARDIOCARDITES. Bl. A genus separated from Cardita, Auct. 
Thus described (translation) "oval species, with the inferior mar- 
gin nearly straight, or a very little inflated, crenulated and 
completely closed. Ex. La C. Ajar, Adans Seneg. pi. 16. fig. 2." 

CARDISSA. Sw. A genus composed of those species of Cardium 
Auct. which are heart-shaped. Ex. C, dionaeum, fig. 122. And 
C. Cardissa. v 

CARDITA, Brug. Fam. Cardiacea, Lam. Submytilacea, BL — 
Descr. Equivalve, inequilateral, ovate, subquadrate or oblong, 
marked externally by ribs radiating from the umbones and termi- 
nating in a crenulated margin on the inner surface ; cardinal 
teeth in one valve, one long, thick, oblique ; another short, more 
straight ; in the other valve one long, oblique, thick. Muscular 
impressions two in each valve, rather oval; palleal impression 
not sinuated, — Obs. This description includes Lamarck's genus 
Venericardia, which, although consisting of the more oblong 
species, is not considered sufficiently distinct to justify the 
separation. Cypricardia is distinguished from this genus by a 
remote lateral tooth. Mediterranean, Africa, East Indies, &c 
Cardita calyculata, fig. 124. 

CARDIUM. Auct. Fam. Cardiacea, Lam. Conchacea, Bl. — Descr. 
Equivalve, sub-equilateral, sometimes gaping posteriorly, orna- 
mented on the outside by ribs radiating from the umbones ; 
cardinal teeth, two in each valve, locked into each other cross- 
wise, lateral teeth, two in each valve, remote; muscular im- 
pressions, two in each valve ; palleal impression entire. Liga- 
ment external, inflated. — Obs. Although this genus includes 
many remarkable forms, the characters are so easily defined that 
there is no difficulty in distinguishing it from any other genus. 
C.angulatum,fig. 123. C. Grcenlandicum, fig. 123*. Aphrodita, 
Lea. C. Hemicardium, fig. 123**. fig. 122. C. Dionseum. It is 

H 



98 CAROCOLLA. 

somewhat surprising that this genus, which contains some of the 
most beautiful forms of bivalve Testacea, should have been left 
till quite lately without any attempt to revise the species and 
settle the synonyms. The author of this Manual has endeavoured 
to remedy this defect by publishing a catalogue of all the species 
hitherto known, which amount to 97, including many new species 
described by him in the " Proceedings of the Zoological Society," 
in 1840. Parts 46 to 51, 149 and 150, and 177 to 184 of his 
Conchological Illustrations contain figures of 60 species. Cardia 
are frequent in all climates. 

CARINARIA. Auct. Class, Cephalopoda. Division, Monotha- 
lamia, Lam. Fam. Nectopoda, Bl. — Descr. Symmetrical or nearly 
so, conical, thin, glassy, fragile, patelliform; with a fimbriated 
dorsal keel; apex convolute, bent forwards; aperture oval, pointed 
at the dorsal extremity. Hab. Amboyna, Indian Ocean, and Medi- 
terranean Sea. — Obs. A most singular and beautiful shell, re- 
markable for its transparency, its fragile structure, and the 
dorsal keel, whence it derives its name. It was once so rare that 
a single specimen was known to realize one hundred guineas. 
Fig. 488. C. Mediterranea. 

CAMNATED. (From Carina, a keel.) Applied to any shell having 
a raised, thin ledge, passing round a whorl or any other part of a 
shell, as in Carinaria, fig. 488. 

CARINEA. Sw. A genus formed for the reception of Ovulum 
gibbosum, Auct. and similar species, fig. 443. 

CARINELLA. Adanson. Lutraria papyracea, Lam. Ligula, 
Leach. Fam. Mactracea, Lam. Fig. 77. 

CARINIDEA. Sw. A sub-genus of the genus Canthorbis, Sw. 
(Turbo.) thus described, "Imperforate ; spire pyramidal, acute ; 
basal whorl concave beneath, and carinated round its circum 
ference ; aperture oval, entire, slightly angulated at the base of 
the pillar, which turns inwards. C. concavus, Martini, 168, fig. 
1620, brevispinosus ? Sow. Gen. (Turbo,) fig. 1." 

CAROCOLLA. Auct. Fam. Colimacea, Lam. — Descr. Orbicular, 
depressed, with the outer sides of the whorls angulated or keeled, 






CASSIDEA. 99 

whorls few ; peritreme reflected ; columella contiguous to the 
axis; epidermis thin. — Obs* This genus differing from Helix only 
in the whorls being angulated, is hardly distinct enough from the 
latter to justify the separation In De Ferrusac's system these 
species constitute the division Helicigona, of the genus Helix. 
C. Lamarckii, fig. 277. East and West Indies, Philippines, South 
America and Europe. 

CARTILAGE. See Ligament. 

CARYCHIUM. Mull. Fam. Auriculacea, Bl. Colimacea, Lam. — 
Descr. Oblong or cylindrical, with gradually increasing whorls, 
few in number ; aperture straight, short, with a fold on the 
columella.— Ohs. This genus of minute land shells differs from 
Auricula chiefly in the soft parts. De Furrusac enumerates three 
species, C. Lineatum, C. Corticaria, (Odostomia, Flem.) and C. 
Minimum, fig. 301. De Blainville places it in his genus Auricula, 
as " species with two folds and a posterior tooth on the columella," 
giving a figure of A. Mysotis as his example, and quoting the 
name Phitia, Gray. Europe. 

CASSIDARIA. Lam. (From Cassis) Fam. Purpurifera, Lam 
Entomostomata, Bl. — Descr. Oval, ventricose, spirally grooved 
and tuberculated, with a short turrited spire and a large aperture, 
terminating anteriorly in a recurved canal ; outer lip thickened, 
reflected, undulated or denticulated ; inner lip expanded over a 
part of the body whorl and the columella, with part of its lower 
edge free. — Obs. The recent species of this genus are not nume- 
rous; the few fossil species occur in the tertiary strata. C. 
carinata is found in Calc-grossier and London Clay. In general 
form this resembles Cassis, but is at once distinguished by the 
canal, which does not turn abruptly back, but is slightly curved 
upwards. Oniscia(C. Oniscus, &c. Lam.) is distinguished by the 
shortness of the canal, and the granulated surface of the inner lip. 
Fig. 407* C. Echinophora. Mediterranean. 

CASSIDEA. Sw. (from Cassis.) A genus composed of those 
species of the genus Cassis, Auct. which have the "aperture 
wide ; outer lip never broad or flattened, but sometimes slightly 
inflected ; inner lip spreading, but never dilated or detached 

h 2 



100 CATOPHRAGMUS. 

beyond the base into a prominent rim." East Indies. Ex. C. 
Glauca, fig. 411. 

CASSIDULA. Humph. Pyrula, Auct. 

CASSIDULINA. D'Orbigny. A genus of microscopic Foraminifera. 

CASSIS. (A helmet.) Fam. Purpurifera, Lam. Entomostomata, 
Bl. — Descr. Oval or triangular, ventricose, thick, generally tu- 
berculated, with a short varicose spire ; aperture long, sometimes 
narrow, with the outer lip thickened and reflected, generally den- 
ticulated; the inner lip spread over the surface of the body 
whorl, indented and incrassated at its inner edge ; canal turned 
suddenly over the back of the shell. Hab. Seas of tropical 
climates. The fossil species are rare, occurring in the tertiary 
strata. — Obs. The large, common species of this well known 
genus are used for shell cameos and as ornaments on chimney 
pieces, grottos, &c. and are remarkable for the triangular disc, 
presented by the inner lip, which, in many species, is thickened 
and spread over the front of the body whorl and the angulated 
outer lip. The smaller, more rounded species, which have widened 
apertures, have been separated by Swainson, under the generic 
name Cassidea. The C. rufa, coarctata, &c. are formed by Mr. 
Stutchbury into a new genus under the name Cypr^cassis, for 
reasons which will be stated under the word. Cassidariais distin- 
guished by the gradual curve of the canal. Fig. 410 is Cassis 
tuberosa, diminished. 

CASTALIA. Lam. Fam. Trigonees, Lam. — Descr. Fluviatile, 
equivalve, inequilateral, trigonal, with corroded umbones ; hinge 
with two laminar, transversely striated teeth, one of which is 
posterior, remote from the umbones, short, divided, the other 
anterior, elongated ; epidermis thick ; internal surface pearly. 
Lamarck, in describing this shell, states, that he regards it as 
intermediate between Trigonia and Unio. It should, however, 
certainly have been placed in the family of " Nayades," and per- 
haps should form a part of the genus Unio itself. C. ambigua, 
Lam. fig. 140. South America. 

CATILLUS. Brong. (A little dish.) Inoce ramus, Sow. 

CATOPHRAGMUS. Sow. (From Karw, beneath ; ^pay/tog, a place 



CEPHALOPHORA. 101 

paled in.) Order, Sessile Cirripedes, Lam. — Descr. Light prin- 
cipal valves, cemented side by side in a circle ; eight small 
pointed valves beneath, covering the joints of the upper circle, 
and numerous still smaller valves forming the base of the shell ; 
operculum, four valves. — Obs. This is the only genus of Sessile 
Cirripedes, consisting of eight principal valves, excepting Octo- 
meris, which is destitute of the accessary pieces from which the 
genus derives its name. Fig. 23. C. imbricatus. South Africa. 

CAUDAL CANAL. The elongated hollow process which terminates 
the aperture anteriorly of some univalve shells. For instance, 
Murex Haustellum, fig. 396, has an elongated caudal canal. 

CELLANTHUS. Montf. Vorttcialis, BI. A genus of mi- 
croscopic Foraminifera. 

CELLULACEA. Bi. The second order of Cephalophora, Bl. 
consisting of doubtful microscopic bodies, with a number of 
variously arranged shells, as distinguished from the true Poly- 
thalamia, BL or chambered shells. See Foraminifera. 

CEMORIA Flemingii. Leach. A small patelliform shell, dif- 
fering from Fissurella, in having the fissure placed behind the 
apex, which is produced, pointed and incurved. It is the Patella 
Fissurella, Mull. Patella Noachina, Chemn. F. Noachina, Sow. 
Puncturella, Lowe. Fig. 244. Cemoria Flemingii. Scotland and 
Tierra del Fuego. 

CENTRAL. A term used to indicate the position of the muscular 
impression of a bivalve shell when it is near the centre of the 
inner surface. It is also applied to the siphon perforating the 
septum of a chambered shell when it is placed near the centre of 
the plate, >Sw5-central is also used as a comparative term, to 
indicate the position of the siphon, or of the muscular impres- 
sion, is near the centre. Thus in Placuna (fig. 184), the muscular 
impression is central : in Exogyra (fig. 183), it is sw6-central. 

CEPA. Humph. Anomia, Linn. 

CEPHALOPHORA. Bl. The first class of Malacozose, Bl. Di- 
vided into: Order 1. Cryptodibranchiata ; 2. Cellulacea ; 3. 
Polythalamacea. The first consisting of Cuttle-fish, &c. which 



102 CERITHIUM. 

are destitute of shells ; the second composed of those microscopic 
cellular bodies, which are regarded as shells by some authors ; 
and the third containing the true chambered shells. 
CEPHALOPODA. Lam. (Cephalopodes.) (Ke^aX^, kephale, head ; 
kovq, ttqSog, podos, foot.) The fourth order of the class Mol- 
lusca, Lam. containing molluscs, which are characterized by 
having a series of arms snrrounding the head, which is placed 
above a sack-shaped body. This order is divided into Poly- 
thalamia, or many-chambered shells ; Monothalamia, or single- 
chambered cephalopods ; and Sepiaria, or cuttlefish. Fig. 4G3 
to 488. 
CEPOLIS. Montf. Belonging to the genus Helix, Auct. 
CERATODES. Guild. (Kepar^rjg, like a horn.) A genus com- 
posed of the flat, orbicular species of Ampullaria, Auct. 
which present so near a resemblance to the Planorbes, as to have 
been considered as belonging to them. Planorbis has, however, 
a horny texture, and no operculum, and it is always reversed, 
which may be observed by placing the spire upwards . Fig. 320, 
represents Ampullaria (Ceratodes) Cornu-arietis. 
CERIPHASIA. Sw. A sub-genus of Melanianse, thus described, 
" Cerithiform ; outer lip thin, dilated at the base ; aperture 
small, slightly emarginate, without any internal groove ; inner 
lip thin. C. sulcata, Sw. fig. 38. p. 204." (Sw. Lard. Cyclop. 
Malac. p. 342.) 
CERITHIUM. Brug. Fam. Canalifera, Lam. Entomostomata, 
Bl. — Desc. Elongated, ribbed, tuberculated, or rarely smooth, 
with a lengthened, turrited, pointed, pyramidal spire, consisting 
of numerous whorls ; aperture sub-quadrate, terminated ante- 
riorly by a tortuous canal ; outer lip thickened, sometimes re- 
flected, expanded ; inner lip thickened posteriorly ; operculum 
horny, spiral, with numerous whorls. — Obs. The fresh-water 
shells described as Cerithia by Lamarck, are separated under the 
name Potamis, and may be known by the thick, horny epider- 
mis. Triphora, Desh. has the canal closed, except at the ex- 
tremities. Cerithium Telescopium, does not appear to present 



CHAMACEA. 103 

the same characters as the other Cerithia, and has been separated 
by some writers under the generic name Telescopium. Cerithium 
Aluco, fig. 372. Mediterranean, East and West Indies, Coasts of 
the Pacific, Gallapagos, Australia, &c. Some small species are 
British. Fossils are numerous in the tertiary beds. 

CERVICOBRANCHIATA. Bl. The second order of Paracephalo- 
phora Hermaphrodita, Bl. containing symmetrical patelliform 
shells, divided into the families Retifera and Branchifera. 

CETOCIS. Montf. Fam. Orthocerata, Lam. and Bl. Placed by 
De Blainville in his section of Belemnites, characterized as having 
small folds at the apex. Ex. B. Penicillatus. 

CETOPIRUS. Ranz. Coronula Bal^naris, Auct. fig. 16. 

CHAM A. Auct. Fam. Chamacea, Lam. and Bl. — Descr. Ine- 
quivalve, irregular, thick, foliaceous, attached by the umbo of the 
lower and larger valve. External ligament placed in a groove, 
following the curve of the umbones. Umbones spiral, coiled 
round on the back of the valves ; hinge with a thick, crenated, 
lengthened tooth, in one valve, entering a corresponding cavity in 
the hinge margin of the other ; muscular impressions, two in each 
valve, distinct, lateral. — Obs. The Linnsean genus Chama, in- 
cluded the beautiful shells now called Tridacna. These are ex- 
ceedingly different from the true Chama, being regular and 
unattached. The Chama (Tridacna) gigas, when at its full age 
and development, is the largest shell known. Specimens have 
occurred weighing upwards of 500 lbs., and measuring two feet 
across. Diceras may be known from Chama by the spiral horns 
into which the umbones are produced ; Isocardia, by the regu- 
larity of the shells, and it is hardly necessary to mention Spon- 
dylus, which may be known by the triangular disc between the 
umbones ; Cleidothserus, Stutch. which resembles Chama in 
general form, has a separate bony appendage attached to the 
hinge, and may, moreover, be distinguished by its elongated 
muscular impression. Fig. 153, C. Lazarus. E. and W. Indies. 

CHAMACEA. Bl. The seventh family of the order Lamellibran- 
chiata, Bl. containing the genera Chama, Diceras, Etheria, Tri- 
dacna, Isocardia and Trigonia. 



m 



CHILINA. 



CHAM ACE A. Lam. A family belonging to the order Conchifera 
Dimyaria, Lam. described as inequivalve, attached, irregular ; 
with or without a single rough tooth on the hinge ; with two 
lateral muscular impressions in each valve. This family contains 
the genera— 

1. Chama. Leafy; umbones spiral. Fig. 153. 

2. Etheria. Very irregular, pearly, without teeth. Fig. 155. 

3. Diceras. Like Chama, but the umbones free, produced. 

Fig. 154. 

CHAMBERED. When the cavity of a shell is not continuous, but 
is divided by shelly diaphragms or septa, it is said to be cham- 
bered. This is the case with the shells of the Polythalamous 
Cephalopoda, as in the Nautilus (see Introduction). The character 
is not confined to these, as it occurs in some species of Spoil- 
dyli, and in several turrited univalves. 

CHAMOSTR^A. DeRoissy. Cleidoth^rus. Stutch. 

CHARYBS. Montf. A genus of microscopic Foraminifera. 

CHELIBS. Montf. A genus of microscopic Foraminifera. 

CHELINOTUS. Sw. A genus of " Haliotid^e/' Sw. including 
Velutina, Lam. a species of Sigaretus from Tonga, and Coriocella, 
Bl. Thus described, "Animal cheloniform, broad ; depressed; 
the mantle larger than the shell, lobed in front ; tentacula two, 
short, obtuse ; eyes basal ; mouth circular ; shell ear-shaped, thin, 
fragile, imperforate ; pillar none." 

CHELONOBIA. Leach. Coronula Testudinaria, Auct. Fig. 15. 

CHERSINA. Humph. Achatina, Lam. 

CHICOREUS. Montf. A generic division of the genus Murex, 
consisting of such species as have three ramified varices. Ex- M. 
inflatus, fig. 395. 

CHILINA. Gray Fam. Auriculacea, Bl. Colimacea, Lam. — 
Descr. Oval, thin, covered with an olive green epidermis ; spire 
rather short, consisting of few whorls ; aperture large, oval, 
rounded anteriorly ; outer lip thin, joining the inner lip without 
a sinus ; inner lip spread over part of the body whorl, termi- 
nating in a thick columella with one or two folds. — Obs. These 



CHITON. 105 

shells differ from the true Auriculae in the thinness of the outer 
lip. C. Dombeyana (Auricula Dombeyana, Auct.) Fig. 300. The 
illustrated catalogue published by the author (Sow. Conch, illustr. 
parts 135, 136) contains 13 species. Rivers of South America. 

CHILOTREMA. Leach. A sub-genus of Helix, containing Helix 
lapicida, Auct. Gray, Turton, p. 140. 

CHIMOTREMA. — ? Belongs to Helix. 

CHIONE. Megerle. Cyther^a maculosa, (fig. 117, c.) sulcata, 
circinata, &c. Auct. and other similar species. 

CHIRON A. Gray. A genus of Balanidse, the shells consisting 
of six parietal valves and two opercular valves ; the upper edges 
of the parietal valves are sloped and the structure is not tubular. 

CHISMOBRANCHIATA. Bl. The second order of the first 
section of Paracephalophora Monoica, Bl. Those Mollusca be- 
longing to this order which have shells, have them either internal 
or external, but always scutiform, with depressed spires and 
wide, haliotoid, oblique apertures, without a columellar lip pro- 
perly so called. This order partly answers to the family Macros- 
tomata, in the system of Lamarck. It contains the genera 
Coriocella, Sigaretus, Cryptostoma, Oxinoe, Stomatella and 
Velutina. 

CHITON. Auct. (x iT0V > an integument.) Fam. Phyllidiana, 
Lam. Class, Polyplaniphora, Bl. — Descr. Oval, consisting of 
eight arched valves arranged in a series across the body of the 
animal and fixed in the skin which forms a rim around them, 
sometimes scaly, spinose, or rugose, sometimes smooth. — Obs. 
The genus Chiton, commonly called "Coat of Mail," from its re- 
semblance to jointed armour, remains to the present day in exactly 
the same state with regard to its boundaries as that in which 
Linnaeus found it, and in which he left it. That illustrious 
Naturalist placed it among the multivalves in his purely Concho- 
logical system, although the animal is totally different from the 
Cirripedes. The shells are prettily marked, and are found attached 
to the rocks in all seas of Tropical and Southern climates, but fossil 
species are almost unknown. Fig. 227, C. Spinosus. The genus 



106 CHRYSOSTOMA. 

is divided by Guilding into Chiton, Canthopleura, Phakellopleura, 
Chitonellus and Cryptoconchus. Zool. Journ. xvn. p. 27. The 
author of this manual has lately attempted a revision of this inter- 
esting but neglected genus, and has given a catalogue of all the 
species hitherto known, as far as they could be identified among 
the confused mass of synonyms and descriptions to be found in 
the works of various Conchological writers. This catalogue is to 
be found in his Conchological Illustrations, and refers to figures 
of 102 species, 92 of which are contained in parts 38 to 45, 
and 159 to 176. 

CHITONELLUS, Lam. (From Chiton ) Separated by Lamarck 
from Chiton, on account of the valves being placed at a greater 
distance from each other, the soft integument of the animal in- 
tervening. Fig. 228, C. striatus. Philippines. 

CHLOROSTOMA. Sw. A sub-genus of " Troch^ee/' Sw. 
(Trochus) of which C. argyrostoma is given as an example. 
Sw. Lard. Cyclop, p. 350. 

CHONDRUS. Hartmann. Abida, Leach. A genus formed for 
the reception of Pupa secale, Drap. Pupa Juniperi, Montague, 
which have plaits in the aperture. 

CHRYSOAR. Montf. Probably a species of Orthoceras. 

CHRYSODOMUS. Swains. "Distinguished from Fusus, by the com- 
parative shortness of the basal channel, and the ventricose or en- 
larged shape of the body whorl. The beautiful orange-mouthed 
Whelk of England is a typical example ; and the few others now 
known are all of a very large size, and chiefly found in Northern 
Seas, where they represent the more elegant Fusi of tropical lati- 
tudes; the outer lip is always thin and smooth," Sw. page 90, 
paragraph 78, described at page 308. 

CHRYSOLUS. Montf. Polystomella, Bl. A genus of micro- 
scopic Foraminifera. 

CHRYSOSTOMA. Sw. A genus of the family " Rotellinse," Sw. 
Thus described " Shell turbinate ; the whorls few and convex ; 
aperture effuse, round ; inner lip thickened just over, and almost 
concealing the umbilicus. Nicobaricus, Martini, 182 fig. 1822 — 
5." Sw. Lard. Cyclop. Malac. p. 327. 



CIONELLA. 107 

CHTHALAMUS. Ranz. Fam. Balanidea, Bl. Order, Sessile 
Cirripedes, Lam. — Bescr. " Shell much depressed, valves thick, 
thickened at the base, with prominent areas ; operculum nearly 
horizontal, composed of four valves." — Obs. This description 
would apply generically to the shell called Platylepas in the 
British Museum, only nothing is said about the prominent plates 
jutting from the internal surface of the valves. The difference 
between this genus and Balanus consists principally in the hori- 
zontal position of the operculum, and general flatness of the shell. 
C. stellatus, fig. 18. 

CIBICIDES. Montf. A genus of microscopic Foraminifera. 

CIDARIS. Swains. A genus composed of Turbo Smaragdus, pe- 
tholatus, and other similar species. The word Cidaris is, how- 
ever, already in use for a genus of Echinae. 

CIDAROLLUS. Montf. A genus of microscopic Foraminifera. 

CILIATED, (ciliae, hairs.) Having minute hairs as in Orbicula, 
Lingula, &c. and the jointed feelers of the Cirripedes. 

CIMBER. Montf. Navicella, Auct. 

CINERAS. Leach. (Cinereus, ash-coloured.) Order, Peduncu- 
lated Cirripedes, Lam. — Bescr. Animal with a quadrilateral 
body, supported on a fleshy peduncle, with an opening in front 
of the upper part for the passage of a bunch of ciliated tentacula. 
Immediately above this aperture is a pair of small elongated 
valves, placed in a nearly horizontal position ; at the lower part 
is another tripartite pair placed perpendicularly, one on each side, 
and a narrow, angulated, keel-shaped piece placed at the back. — 
Obs. The nearest approach to this genus is Otion. (C. Vittatus, 
fig. 42.) Found upon substances floating in the sea. 

CINEREOUS. (Cinereus) Ash-coloured. 

CINGULA. Fleming. Rissoa, Leach. 

CIONELLA. Jeffreys. Fam. Colimacea, Lam. — Bescr. Oblong 
or elongated; last whorl large; apex rather acute; columella, 
sub-interrupted; aperture canaliculated, sub-effuse at the base; 
margins very unequal; no umbilicus. Bulinus octonus, lubri- 
cus, acicula, &c. Auct. C. lubrica, fig. 285. 



108 CLAUSILIA. 

CIRCE. Schum. Venus castrensis, fig. 117 d. V. sulcatipa, ara- 
bica, pectinata, Auct. and other similar species. 

CIRRIPEDES. Lam. The tenth class of invertebrated animals, 
so named from the curled and ciliated branchia which protrude 
from the oval aperture of the shells. The class Cirripedes of 
Lamarck constitutes the entire genus Lepas of Linnaeus. They 
are divided into two sections; first, Sessile Cirr. attached by the 
basal portion of the shell; second, Pedunculated Cirr. supported 
upon a Peduncle. Figs. 14 to 45. 

CIRROBRANCHIATA. Bl. The first order of Paracephalophora 
Hermaphrodita, Bl. This order has been formed for the pur- 
pose of giving a place in the system to the genus Dentalium. 
The animal of which has lungs, consisting of numerous filaments, 
having their basal origin in two radical lobes under the neck. 

CIRRUS. J. Sowerby (cirrus, a tendril.) Fam. Turbinacea, Bl. 
and Lam. — Descr. Spiral, conical, with a hollow axis ; whorls 
contiguous, numerous, rounded, or slightly angulated. — Ofo. 
This fossil genus resembles Trochus, from which it is known by 
the deep funnel-shaped umbilicus. Fig. 349, C. nodosus. 

CISTULA. Humph. Cyclostoma, Lam. 

CLANCULUS. Montf. Trochus Pharaonis, Lam.— Obs. This, 
with several other species, belong more properly to Monodonta, 
Lam. Odontis, Sow. Fig. 361. 

CLATHODON. Conrad. Gnathodon, Gray. 

CLAUSILIA. Drap. (Clausium, a valve or folding door.) Fam. 
Colimacea, Lam. Limacinea, Bl. — Descr. Spire elongated, 
consisting of many volutions; aperture small, sub quadrate, hav- 
ing several tooth-shaped folds on the columella. A small, elastic, 
shelly plate, attached to the columella within, called the Clau- 
sium, its office being to enclose the aperture when the animal 
has retired within the shell. — Obs. This last character distin- 
guishes it from the Pupse, to some of which it bears a very 
near resemblance. Hab. Land, in the central and southern 
parts of Europe, several British species. Fig. 295, C, Macas- 
carensis. 



CLAVATULA. 109 

CLAUSIUM. A name applied to the beautiful contrivance whence 
the genus Clausilia derives its name, consisting of a little bony 
tortuous plate, placed in a groove on the columella. Here it 
serves the purpose of a door, which, when not prevented by 
counteracting pressure, springs forward on its elastic ligament, 
and encloses the animal in his retirement. The aperture is 
opened by pushing back the clausium into the groove. 

CLAUSULUS. Montf. Conch. Syst. 1, 179. A genus of micro- 
scopic Foraminifera. 

CLAVA. Humph. Cerithium, Lam. 

CLAVAGELLA Lam. (Clava, a club.) Fam. Tubieolse, Lam. 
Pyloridea, Bl. — Descr. Two irregular flattish valves, one fixed 
or soldered, so as to form part of the side of an irregular shelly 
tube; the other free within the tube near the base. — Ohs. The 
shells composing this genus are found in stones, madrepores, 
&c. and appear to form the connecting link between Aspergillum, 
which has both valves cemented into the tube; and Fistulana, in 
which both are free. Fig. 45, a fossil Clavagella. Found recent 
on the Coast of Malta and New South Wales. 

CLAVA LITHES. Sw. A genus composed of some fossil shells, 
separated from the genus Fusus, which, having the general form 
of Turbinella Rapa, &c. are considered by Swainson, as holding 
an intermediate station between Fusus and the Turbinellidse. — 
Descr. " Unequally sub-fusiform ; the body whorl, and spire, 
being conic ; and the canal suddenly contracted and attenuated ; 
terminal whorls papillary ; inner lip thick; pillar smooth, C. 
longaevus, clavellatus, Nose, ponderosus, Sw." — Obs. The papil- 
lary spire may form a sufficient reason for separating this genus 
from Fusus, while the absence of plates on the columella places 
them at a still greater distance from Turbinella. 

CLAVATE. When one extremity of the shell is attenuated, and 
the other becomes suddenly ventricose or globular, it is said to 
be Clavate. Ex. Murex Haustellum, fig. 396. 

CLAVATULA. Lam. The generic name by which Lamarck ori- 
ginally distinguished those species of Pleurotoma which were 



110 CLITIA. 

remarkable for the shortness of their canals. In his system, 
however, they are re-united to Pleurotoma. Fig. 381, P. Strom- 
biformis. 
CLAVICANTHA. Sw. A genus separated from Pleurotoma, 
Lam. consisting of species, which are described as "thick, 
sub-fusiform ; the surface rugose, and the whorls sub-coronated ; 
channel short ; slit assuming the form of a short, broad sinus. 
C. imperialis, E. M. 440, spirata, E. M. 440, fig. 5, conica, E. M. 
439, fig. 9, echinata, E. M. 439, fig. 8, Auriculifera, E. M. 439, 
fig. 10." 

CLAVICLE, (clavis, a key.) A little key. This term is applied 
to the bony appendage in the hinge of some species of Anatina, 
(those included in the generic term Lyonsia) Cleidothserus, Myo- 
chama, &c. 

CLAVULINA. D'Orb. A genus of microscopic Foraminifera. 

CLAVUS. Montf. A genus of microscopic Foraminifera. 

CLEIDOTHiERUS. Hutch. (Qaipog, hinge, KXelg, clavicle.) 
Fam. Chamacejfi or Myarise, Lam. — Bescr, Inequivalve, irregular, 
solid, attached ; with one cardinal, conical tooth in the free 
valve, entering a corresponding indenture in the other ; and an 
oblong shelly appendage, fixed by an internal cartilage in a 
groove under the umbones ; muscular impressions, two in each 
valve, one elongated, the other uniform — Obs. This shell is like 
Chama in general form, but is distinguished by the clavicle or 
shelly appendage from which its name is derived. Fig. 75. New 
South Wales. 

CLEODORA. Per. et Les. Fam. Pteropoda, Lam Thecosomata, 
Bl. — Bescr. Thin, transparent, pyramidal, with flat alate sides, 
and oval aperture. Fig. 221, C. cuspidata. 

CLISIPHONITES. Montf. Microscopic. Lenticulina, Bl. 

CLITHON. Montf. Neritina Corona, spinosa, &c. Auct. fig. 325. 

CLITIA. Leach. Fam. Balanidea, Bl. Order, Sessile Cirripedes, 
Lam. — Bescr. Sub conical, compressed, consisting of four un- 
equal valves, two larger and two smaller, joined together side by 
side, by the interlocking of their dentated edges, a process some- 



COCHLITOMA. Ill 

what like that which joiners call dove-tailing. Operculum, 
consisting of two unequal pointed valves. — Obs. Clitia is known 
from Creusia, by the articulations of the valves, and by the 
operculum, which in Creusia consists of four valves. Fig. 
20. C. Verruca, (Lepas Verruca, Gmelin.) Britain and Peru. 

CLOSE. The margins of a bivalve shell are described as being 
close, when there is no hiatus between them in any part, other- 
wise they are described as gaping. 

CLOTHO. Faujas. Fam. Conchacea, Bl. More properly belong- 
ing to the Pyloridea, Bl. ; and the Lithophagidse, Lam.— Descr. 
"Oval, nearly regular, longitudinally striated, equivalve, sub- 
equilateral ; hinge consisting of a bifid tooth, curved like a 
crochet, larger in one valve than in the other." This descrip- 
tion is translated from Blainville, who states that he has never 
seen the shell. Annales du Museum D'Histoire Naturelle, torn. 
9, pi. 17, fig. 4—6. 

CLYPEIFORM. (Clypeus, a shield.) Open, flat, shaped like a 
shield or buckler, as Umbrella, fig. 233, and Parmophorus, fig. 
242. 

CLYPIDELLA. Sw. A sub-genus of Fissurella, described as hav- 
ing one extremity of the shell slightly raised. C. pustula. Sow. 
Gen. fig. 3. 

COAT OF MAIL. A common name given to shells of the genus 
Chiton, on account of their resemblance to jointed armour. 

COBRESIA. Hiibner. Vitrina, Auct. 

COCHLIATE. {Cochleare, a spoon). Applied to any shell or part 
which is hollow and oval, as Patellae, &c. The cavity containing 
the cartilage in Mya, fig. 71, is Cochleate. 

COCHLICELLA. One of the sub-genera into which De Ferrusac 
has divided the genus Helix, consisting of Bulinus decollatus, 
fig. 279, and similar species. See Helix. 

COCHLICOPA. Fer. A sub -genus of Helix, partly correspond- 
ing with Polyphemus of De Montfort, and consisting of species 
of Achatina, which have the outer lip undulated. 

COCHLITOMA. Fer. A sub -genus of Helix, corresponding with 



112 COLIMACEA. 

the genus Achatina, Auct. not including those with undulated 

outer lips. 
COCHLODINA. Fer. A sub-genus of Helix, including the genus 

Clausilia, Auct. 
COCHLODONTA. Fer. A sub-genus of Helix, containing Pupa 

Uva, Auct. &c. 
COCHLOGENA. Fer. A sub-genus of Helix, containing pupi- 

form shells, such as Azeca tridens, fig. 290. 
COCHLOHYDRA. Fer. A sub-genus of Helix, composed of the 

genus Succinea, Auct. 
COCHLOSTYLA. Fer. A sub-genus of Helix, composed of the 

genus Bulinus, Auct. 
COLIMACEA. Lam. This Family, of the order Trachelipoda, 

Lam. includes all land shells, which might with propriety be 

divided into three sections, the first of which contain the follow- 
ing well-known genera : — 

1. Succinea. Oval, transparent, oblique ; animal amphi- 
bious. Fig. 265, 266. 

2. Helix. The type of which is the common snail shell. 
The separation of Carocolla, on account of the angulated 
whorls, or that of Geotrochus, on account of the turbinated 
shape, cannot be well maintained. Fig. 264, 267, 268, 
273 to 276, 278 to 281, 294. 

3. Anostoma. The aperture turned up towards the spire. 
Fig. 271, 272. 

4. Streptaxis. Whorls excentric. Fig. 269, 270. 

5. Bulinus. Oval; aperture entire, including Bulimulus, 
Balea, Cionella, Azeca. Fig. 282 to 285, 289, 290, 296. 

6. Achatina. A notch terminating the columella. Fig. 286 
to 288. 

7. Pupa. Cylindrical ; including Vertigo, Alcea, &c. Fig. 
291 to 293. 

8. Clausilia. Cylindrical, with a clausium. Fig. 295. 
Obs. The above are united in the system of De Ferrusac under 

the generic name Helix, and divided into sub-genera as 
explained under that word. 



COLUMBELLA. 113 

The next section, included in the family Auriculacea, Bl.. con- 
tains the genera Auricula, Chilina, Carychium, Marinula, 
Scarabseus, and Partula. Fig. 297 to 302. 

The third section contains the following genera of land shells 
with opercula. 

1. Cyclostoma- Aperture round; operculum spiral. Fig. 
303, 304. 

2 Nematura. Last whorl contracted; operculum spiral. 
Fig. 305. 

3. Helicina. Aperture semilunar or angulated ; operculum 
concentric. Fig. 306, 307. 

4. Pupina. Shell polished; operculum concentric; aperture 
round. Fig. 

5. Strophostoma. Aperture turned up towards the spire, 
like Anostoma, but said to have an operculum. Only 
known fossil. Fig. 97. 

COLUMBELLA. Auct. (Columba, a dove.) Fam. Columel- 
lata, Lam. — Bescr. Thick, oval, or angular ; with short spire, 
and long narrow aperture, contracted in the centre, and termi- 
nating in a short canal ; outer lip thickened and dentated ; 
inner lip irregularly crenated. Epidermis thin, brown. Oper- 
culum very small, horny. — Obs. Those species of Mitra, which 
resemble Columbella in shape, may easily be distinguished by the 
plaits on the columella. The Columbelloe are marine, and few 
fossil species are known. Fig. 430, C. Mercatoria. Swainson 
has divided this genus into the following : Columbella, consisting 
of C. Mercatoria, &c. ; Pusiostoma, consisting of the Strombiform 
species ; Ci'assispira, which is most probably a Cerithium ; Ni ■ 
tidella, consisting of the smooth species ; Conidea, consisting of 
the more conical species ; another set of the more conical species 
has been removed from this family, and placed in that of the 
" Coninee," but as they are separated by no essential character, 
'we suppose this has merely been done for the purpose of com- 
pleting the ' ' circle" of the last mentioned family, which other- 
wise would not have reached the required number of five. Medi- 

i 



114 COLUS. 

terranean, East and West Indies, South America, Coast of Cali- 
fornia, Gallapagos, &c. 

COLUMELLA. A solid column formed by the inner sides of the 
volutions of a spiral univalve. It is sometimes described as the 
inner lip of the aperture, of which it forms a part ; but the term 
would be more properly confined to that portion of the inner lip 
which is seen below the body whorl, over which the remainder of 
the lip is frequently spread. All the inner edge of the aperture, 
including that part of it which covers the body whorl, is called 
the columellar lip. In fig. 431, the anterior termination of the 
columella is indicated by the letter c. The axis, is an imaginary 
line drawn strictly through the centre of the whorls, whether their 
inner edges form a solid column or not. 

COLUMELLAR LIP. The inner lip. See Columella. 

COLUMELLATA. Lam. A family of the order Trachelipoda, 
Lam. containing the following genera : — 

1. Mitra. Elongated; aperture narrow ; strong folds on the 

columella ; including Mitrella, Mitreola, Tiwa, and Co- 
nohelix. Fig. 431, 432. 

2. Marginella. Outer lip reflected ; including Volutella, 
Persicula, Gibberula, and Glabella. Fig. 437. 

3. Columbella. Outer and inner lips denticulated or granu- 
lated. Fig. 430. 

4. Voluta. Outer lip thickened ; folds on the columella ; 

aperture generally wide ; apex papillary ; including Sca- 
phella, Harpula, Volutilithes, Cymbiola. Fig. 433, 436. 

5. Melo. Shell comparatively light ; spire short, sometimes 
hidden ; apex round, spiral ; folds on the columella la- 
minar. Fig. 435. 

6. Cymba. Upper edge of the aperture separated from the 
body whorl by a flat disc ; apex mammillated, irregular ; 
folds on the columella. Fig. 434. 

7. Volvaria. Cylindrical ; aperture long, narrow ; folds on 
the columella ; spire hidden. Fig. 439. 

COLUS. Humphrey. Fusus, Lam. 



CONCHACEA. 115 

COMPLANARIA. Sw. A subgenus of Alasmodon (Unio), 
thus described, " shell winged ; the valves connate; the bosses 
very small and depressed ; cardinal teeth two or three ; lateral 
teeth represented by irregular grooves. C. gigas (Unio), Sow. 
Man. fig. 141. Alasmodon complanatus, Say) C. rugosa, Sw." 

COMPRESSED. Pressed together, or flattened. The application 
is the same as in common use. A Patella may be described as a 
vertically compressed cone. A Ranella, on account of the two 
rows of varices skirting the whorls, appears, as it were, laterally 
compressed. A bivalve shell is said to be compressed when it is 
flat, that is, when but a small cavity is left in the deepest part 
when the valves are closed. Perhaps the Placuna placenta, fig. 
184, is the most remarkable instance of this. 

CONCAMERATIONS. (Con, with, camera, a chamber.) A series 
of Chambers joining each other, as in Nautilus, Spirula, &c. 

CONCENTRIC. A term applied to the direction taken by the lines 
of growth in spiral and other shells, {longitudinal of some 
authors.) Every fresh layer of shelly matter forms a new circle 
round an imaginary line, drawn through the centre of the spiral 
cone, down from the nucleus. When the edges of the successive 
layers are marked by any external characters, the shell is said to 
be concentrically striated, banded, grooved, costated, &c. A fine 
illustration of the latter is to be seen in the Scalaria or Wentle- 
trap, fig. 351, Lines, bands, ribs, &c. in the opposite direction, 
(transverse of some authors,) are "radiating" in bivalves, as the 
ribs of Cardium, fig. 123, and "spiral" in univalves, that is, 
following the direction of the whorls, as the bands of colour in 
Pyramidella, fig. 342. 

CONCHACEA. Bl. The eighth family of the order Lamellibran- 
chiata, Bl. The shells are described as follows : nearly always 
regular, valves closed all round ; apices curved towards the an- 
terior ; dorsal hinge complete, with teeth and ligament ; the 
latter external or internal, short and thick; two distinct mus- 
cular impressions, united at the lower part by a parallel impres- 
sion, which is frequently sinuated at the posterior. The genera 

i 2 



116 CONCHACEA. 

described in this family are divided into three seetions. First, 
those which are regular, and have distant lateral teeth, Cardiuni, 
Donax, Tellina, Lucina, Cyclas, Cyprina, Mactra, and Erycina. 
Second, those which are regular, and have no distant lateral 
teeth, Crassatella and Venus. Third, those which are irregular, 
Venerupis, Coralliophaga, Clotho, Corbula, Sphsenia, and Un- 
gulina. 
CONCHACEA. Lam. A family of Lamarck's order Conchifera 
Dimyaria. Regular, unattached in general, closed at the sides. 
They are always more or less inequilateral. The Marine Con- 
chacea are those which inhabit the sea. The fluviatile Conchacea 
are those which are found in rivers, ponds, &c. Each of these 
contain various genera, which may be arranged as follows : — 

Fluviatile. 

1 . Cyrenella. Three cardinal teeth ; ligament long ; shell 
thin. Fig. 114. 

2. Cyclas. Thin, oval ; cardinal and lateral teeth ; anterior 
side shortest, including Per a. 

3. Pisidium. The same, with the posterior side shortest. 

Fig. 112. 

4. Cyrena. Thick; cardinal and lateral teeth. Fig. 113. 

5. Potamophila. Two thick cardinal teeth. Fig 115. 

Marine. 

1. Cyprina. Two cardinal teeth, and one remote lateral 
tooth. Fig. 116. 

2 Venus. Three cardinal, no lateral teeth ; including Ar- 
temis. Fig. 118, 119, 11 9a. 

3. Cytherea. Several cardinal teeth ; one very short lateral 

tooth. Fig. 117, 117a, 1176, M7c, 117 d. 

4. Pull astra. Cardinal teeth notched, otherwise like Venus. 

Fig. 120. 

5. Astarte. Three cardinal teeth ; ligament short. Fig. 

110. 
Venericardia belongs to the Cardiacea. 






CONE. 117 

C0NCH1FERA. Lam. The 11th class of Invertebrata, consisting 
of all those animals which have bivalve shells. Lamarck divides 
theclass into Dimyaria, which have two adductor muscles ; and 
Monomyaria, which have but one. 

CONCHOLEPAS. Montf. (Concha, a shell ; lepas, a stone or 
rock.) Fam. Purpurifera, Lam. Entomostomata, Bl. — Descr. 
Oval, imbricated, thick ; with a very short spire and large oval 
patelliform aperture, terminating anteriorly in a slight emargi- 
nation ; outer lip crenated, with two produced points or teeth 
towards the anterior , inner lip smooth, nearly flat, reflected over 
the last whorl, so as nearly or entirely to cover it ; operculum 
horny. Marine, only one species known, from Peru. — Obs. This 
shell is placed near Patella by Lamarck, on account of its large 
open aperture ; but having a horny operculum, and resembling 
Purpurea in other respects. Fig. 418. Concholepas Peruviana. 

CONCHOTRYA. Gray. (Concha, a shell ; Tpvo, (tryo) to bore.) 
Order, Pedunculated Cirripedes, Lam. — Descr. Five pieces, two 
pairs ventral, one single ; shaped like Pentelasmis. Found in 
holes. 

CONCHYLIOMORPHITE. A term used by De Blainville to desig- 
nate the cast or model of a fossil shell, formed by a siliceous sub- 
stance which has entered or surrounded it when in a liquid state, 
and subsequently become hardened into flint. The shell has 
afterwards decomposed or fallen off by accident, leaving its ex- 
ternal or internal characters to be conjectured from the monu- 
mental impressions that remain. 

CONCHYTA Hupsch Mus. Calceola, Lam. 

CONE. A common name for shells of the genus Conus. 

CONE. This mathematical term is used by conchologists in its 
utmost latitude of signification to express a body, which in its 
formation, commences in a small point, called the apex, and in- 
creases in width towards the conclusion or base. It is applied to 
all shells, whether the increase in width be gradual or sudden ; 
or whether in its growth, its takes a straight, oblique, curved, or 
spirally-twisted course In this sense, a bivalve would be de- 



118 CONILITES. 

scribed as a pair of rapidly enlarging, oblique cones, and the 
aperture of every spiral shell would be its base. But this phra- 
seology being in disuse, it is only mentioned here that it may be 
understood when occasionally met with. 

CONELLA. Sw. A genus composed of species of the genus Co- 
lumbella, Lam. which have a conical form, and which, on that 
account, are considered by Swainson as belonging to his family 
of Coninae. Swains. Lardner. Cyclop. Malac. described at p. 312. 
C. picata, Sw. fig. 17, a. p. 151. 

CONFLUENT. A term applied to two parts of a shell when they 
gradually flow into each other, as, for instance, the inner and 
outer lips of Univalves when they pass into each other at the 
anterior extremity, without the intervention of a notch or angle. 

CONIA. Leach. Fam. Balanidea. Order, Sessile Cirripede's, 
Lam. — Descr. Four rather irregular valves, of porous struc- 
ture, placed side by side, so as to form a circular cone, sup- 
ported at the base on a shelly plate, and closed at the aperture by 
an operculum consisting of four valves in pairs. Distinguished 
from Creusia by its porous structure and by its flat support ; that 
of Creusia being cup-shaped. Fig. 21, Conia porosa. 

CONICAL. A term applied in the ordinary sense, and not as ex- 
plained above, under the word Cone. 

CONIDEA. Sw. A genus separated from Columbella, Lam. thus 
described, " Mitra shaped, fusiform ; spire equal or longer than 
the aperture ; the whorls tumid ; outer lip slightly gibbous above, 
contracted below ; margin not inflected ; striated within ; inner 
lip terminating in an elevated ridge, but with the teeth obsolete. 
C. semipunctata, (Columbella, Lam..) Mart. 44. fig. 465, 466." 
Africa. 

CONILITES. Fam. Orthocerata, Lam. & Bl.— Descr. "Conical, 
straight or slightly curved ; having a thin external covering, in- 
dependent of the nut or alveole, which it contains. Alveole 
transversely chambered, sub-separable.' ' ( Translated from Lam.) 
— Obs. The difference between Belemnites and Conilites is that 
the external sheath of the latter is thin, and not filled up with 
solid matter, from the point of the alveole to the apex, as in the 






CONULARIA. 119 

former. De Blainville places in this genus the genera Thalamulus, 
Achelois and Antimomus, Montf. two of which are figured, 
Knor. Sup. Fab. iv. fig. 1. 1. 8. 9. Conilites Pyramidatus, fig. 470. 

CONILITHES. Sw. A sub-genus of Coronaxis, Sw. (Coni, with 
coronated whorls) thus described, i( Conic; spire considerably- 
elevated ; the aperture linear, C. antediluvianus, Sow. Gen. f. 1." 

CONOHELIX. Sw. (Conus and Helix.) The generic name given 
to those species of Mitra which are conical in form. Fig. 432, 
C. marmorata. 

CONOPLiEA. Say. Order, Sessile Cirripedes, Lam. A genus 
composed of Balani, attached to the stems of Gorgonia, having 
their bases elongated. Ex. fig. 27, Balanus Galeatus. 

CONORBIS. Sw. A genus composed of species of Conus 3 such 
as C. dormitor, (Sowerby, gen. fig. 8) which have elevated spires 
and the upper part of the outer lip deeply sinuated. Mr. Swain- 
son considers these fossil species as analogous to the Pleurotomee. 
Sw. Lard. Cyclop. Malac. p. 312. 

CONOVULUM. A genus proposed by Lamarck, to include the 
small, conical species of Auricula, which have the outer lip simple. 
This genus was afterwards abandoned by the author. Ex. fig. 
298, Auricula coniformis. 

CONTIGUOUS. (Contingo, to touch.) A term applied to the 
whorls of spiral shells when they rest upon, or touch each other. 
This is the case in a great majority of instances. When, on the 
contrary, there is a space between the whorls, they are said to be 
non-contiguous, detached, or free. Examples of non-contiguous 
whorls are to be seen in Scalaria, fig. 351 (in this case, the distance 
between the whorls is small), and in Crioceratites, fig. 482. A 
"Columella contiguous to the axis" is when in the centre of the 
shell and takes the place of the imaginary line which forms its 
axis. 

CONTINUOUS. Carried on without interruption, as the siphon in 
Spirula, the varices in Ranella, fig. 394, which, occurring in a 
corresponding part of each whorl, form a continuous ridge. 

CONULARIA. Miller. A genus of Orthocerata, described as coni- 
cal, straight, or nearly so, divided into chambers by imperforate 



120 CONVOLUTE. 

septa ; aperture half closed ; apex solid, obtuse ; external surface 
finely striated. Resembling Orthoceras, but wanting the siphon. 
Fig. 449. 

CONUS. Auct. (Kwvog, a cone.) Fam. Enroulees, Lam. Angy- 
ostomata, Bl. — Descr. Conical, convolute, with a short spire, 
consisting of numerous whorls ; and narrow lengthened aperture, 
terminating in a slight emargination at each extremity ; outer lip 
thin; epidermis thin ; operculum small, pointed, horny. — Obs. 
This well-known genus of shells is easily distinguished from any 
other, by its conical form, its smooth columella, its narrow aper- 
ture, and thin outer lip. The form of the spire varies from flat 
and even partially concave, to a regular pyramidal cone ; and 
the upper edges of the whorls are rounded in some species, an- 
gulated in others, and in some are waved or coronated. The 
variety of marking and the numerous delicate tints of these shells 
have caused them to be highly appreciated by amateur collectors ; 
and many species, as the C. Ammiralis, or admiral ; the C. Gloria 
Maris, or Glory of the Sea; the C. Cedonulli (" I yield to none"), 
and others, have always produced good prices in the markets. We 
give figures of the principal forms, as expressed in the genera 
proposed by De Montfort, of Rhombus, Hermes, Rollus and 
Cylinder, in figures 459 to 462. Many new species were brought 
to this country by Mr. Cuming, and are represented in parts 24, 
25, 28, 29 ; 32, 33, 36, 37 ; 54, 55, 56, 57 ; 147, 148 ; 15 1 to 
158 of the Conchological Illustrations, by G. B. Sowerby, jun. 
See Coronaxis, Swainson. The cones are mostly tropical, some 
are found as far north as the Mediterranean, and south as the 
Cape of Good Hope. The most beautiful species are from the 
East and West Indies. 

CONVOLUTE. (Enroulees, Lam.) A family of the 2nd section 
of the order Trachelipoda, Lam. the genera of which may be dis- 
tinguished as follows : — 

1. Cypr^ea. Lips thickened, inflected, with teeth ; spire 
hidden, including Cyprceovulum, Luponia, Trivia. Fig. 444 
to 450. 



CORBIS. 



121 



2. Ovulum. Lips thickened, inflected, with slight crenula- 

tions ; spire hidden. Fig. 440 to 443. 

3. Erato. Lips thickened, inflected ; spire visible ; a groove 
down the back. Fig. 454. 

4. Terebellum. Cylindrical, open at the anterior extremity ; 
columella smooth ; suture of the spire canaliculated. 
Fig. 451, 452. 

5. Oliva. Columella plaited, swelled into a varix at the ante- 

rior. Fig. 457, 458. 

6. Ancillaria. The same, but the suture of the spire covered 
with enamel. Fig. 455, 456. 

7. Conus. Turbinated, numerous whorls ; spire flat or short, 
conical ; columella smooth. Fig 459 to 462. 

CONVOLUTE. (Con, together ; volvo, to revolve). This term can 
be strictly applied only to symmetrical shells, signifying that the 
volutions are parallel to each other in a horizontal direction, as in 
the Ammonites, &c. ; but the term is also commonly used in de- 
scribing such shells as Conus, in which, the direction of the 
whorls being scarcely oblique, the last whorl almost entirely covers 
those which precede it. This is the case with Lamarck's family 
of Enroulees. Fig. 440 to 462. 

CORALLIOPHAGA. Bl. Cypricardta Coralliophaga, Lam. — 
Descr. Oval, elongated, finely striated from the apex to the base, 
cylindrical, equivalve, very inequilateral ; umbones slightly raised 
and quite anterior ; hinge nearly the same in both valves ; two 
small cardinal teeth, one of which is bifid, placed before a kind 
of lammellated tooth, beneath a very slender external ligament ; 
two small, distant, muscular impressions, united by a striated 
palleal impression, which is strongly striated posteriorly.— Obs. 
This shell, which is found in the empty holes of dead Lithodomi, 
in some instances conforming its shape to its situation, differs 
from Cypricardia of Lamarck, principally in its cylindrical form. 
C. Carditoidea, fig. 92. Mediterranean and East Indies. 

CORBICULA. Megerle. Cyrena, Lam. 

CORBIS. Cuv. (A basket.) Fam. Nymphacea, Lam. — Descr, 
Transverse, oval, thick, ventricose, equivalve, sub-equilateral, free, 



122 CORDIFORM. 

cancellated, with denticulated internal margins ; hinge with two 
cardinal and two lateral teeth in each valve ; of the latter, one near 
and one remote from the umbones ; muscular impressions lunu- 
late, two in each valve, united by an entire palleal impression, with- 
out a sinus. — Obs. This genus, of which only two or three recent 
species are known, resembles many species of Venus and Cytherea 
in general form ; but differs in having lateral teeth, and in the 
palleal impressions which in all the Veneres, &c. is sinuated. 
From Lucina it may be known, not only by its oval form, but 
also by the muscular impressions, which, in Lucina are produced 
into an elongated point ; it will also be distinguished from Tellina, 
by the want of a posterior fold in the valve, for which that genus 
is remarkable, C. Fimbriata, fig. 101, is an inhabitant of the 
Indian Ocean. Several fossil species are found in the recent for- 
mations, above the chalk, at Grignon and Hauteville. 

CORBULA. Brug. (A little basket,) Fam. Corbulacea, Lam. 
Conchacea, Bl. — Descr. Inequivalve, sub -equilateral, transverse, 
gibbose, not gaping ; cardinal tooth in each valve, conical, curved, 
prominent, inserting its extremity into a pit in the opposite hinge; 
cartilage attached to the tooth of the smaller valve, and the pit 
in the larger; muscular impressions, two in each valve, distant, 
rather irregular ; palleal impression posteriorly angulated. — Obs. 
The shells composing this genus were placed in Mya by Linnseus, 
but differ from the true Myae in having a sinus in the palleal im- 
pression, and a prominent ligamentiferous tooth in each valve, 
whereas the Myse have but one. The Corbulse are marine, some 
species inhabiting the British coasts. Fossil species occur abun 
dantly in green sand, London clay, crag, and corresponding for- 
mations. Fig. 89. C. Nucleus. 

CORBULACEA. (Corbulees, Lam.) A family of the order Con- 
chifera Dimyaria, Lam., containing the genera — 

1. Corbula, with a prominent curved tooth. The Fresh- 
water species has been separated under the name Potamo- 
mya. Fig, 89. 

2. Pandora. Thin, pearly, no teeth. Fig. 90. 
CORDIFORM. (Cor, a heart.) Heart-shaped, a term applied ge- 



CORONULA. 123 

nerally to any shell which may be fancied to resemble a heart in 
shape, as Isocardia, fig. 126, and Cardium Dioneeum, fig. 122. 

CORIACEOUS. (Corium, leather.) Of the substance of leather. 
Ex., the integument into which the valves of Chitones are in- 
serted. 

CORIOCELLA. Bl. The animal designated by this name is de- 
scribed by De Blainville as being without any traces of shell, 
either internal or external. This must have arisen from the 
imperfection of the specimen described, probably deprived by 
accident of its shell. The testaceous appendage of the Coriocella 
is now well known to naturalists. It is a milky white, transpa- 
rent shell, shaped like Sigaretus. 

CORNEA, and Pisum, Megerle. Cyclas, Lam. 

CORNEO-CALCAREOUS. A term used to express the mixture of 
horny and shelly matter which enters into the composition of 
some shells, Aplysia, for instance. It is also applied to those 
Opercula, which are horny on one side, and testaceous on the 
other, as that of Turbo. 

CORNEUS. Horny. A species of Patella has had the specific 
name corneus given to it, because its texture more nearly re- 
sembles that of a horn than that of a shell. The epidermis of 
fresh-water shells is of a similar composition. 

CORNUCOPIA. Humph. Lepas, Linn. 

CORONALES. See Coronular Multivalves. 

CORONATED. (Corona, a crown.) Applied to shells when orna- 
mented with a series of points, tubercles, &c, round the upper 
edges of the volutions. Ex. Conus Nocturnus, fig. 459. 

CORONAXIS. One of the two genera into which Swainson divides 
the genus Conus, consisting of those species which have a row 
of tubercles on the upper edge of the whorls, an arrangement by 
which he would in many instances, not only separate between 
two individuals of the same species, but also between two parts 
of the same shell; for instances occur in which the earlier whorls 
are coronated, while the body whorl and the penultimate are per- 
fectly plain. 

CORONULA. {Corona, a crown, dim.) Order, Sessile Cirripedes, 



124 COWRY. 

Lam. Fam* Balanidea, Bl. — Descr. Six radiated valves, joined 
side by side in a circle, forming a depressed cone ; internal struc- 
ture of the valves, porous or chambered; thickened at the base; 
operculum consisting of four valves in pairs; imbedded horizon- 
tally in a cartilaginous substance. — Obs. The shells composing 
this genus are found partly imbedded in the skin of whales, and 
the shells of tortoises, and are therefore destitute of the shelly 
foundation on which the Balani and other Coronular Multivalves 
are supported. C. Testudinaria, (Chelonobia, Leach,) fig. 15. 
C. Baleenarum, (Cetopirus, Ranz.) fig. 16. C. Diadema, (Dia- 
dema, Ranz.) fig. 17. 

CORONULAR MULTIVALVES are those which have their pa- 
rietal valves joined together side by side in a circle, surrounding 
the body of the animal, so as to form a sort of coronet. This is 
the characteristic of the Sessile Cirripedes of Lamarck's system, 
the Balanidea of De Blainville. 

CORRODED. (Corrodo, eat away, consume.) The umbones, apices, 
and other thick parts of shells, are frequently worn away or 
consumed by the action of the element in which they exist. As 
the thickest parts of some shells are the most subject to this 
operation; it appears to the author to arise from the outer surface 
of the shell, being less under the influence of the animal juices 
than the other parts; and therefore, more exposed to the influ- 
ence of the surrounding element. This, however, is not the 
case with respect to the Nayades and other fresh-water shells ; 
with these, corrosion does not take place until after the thick 
epidermis which covers them, becomes wounded by some means 
or other, and then the animal thickens its shell within as fast as 
it is corroded without. 

CORTALUS. Montf. (Conch. Syst. 1. 115.) A genus of mi- 
croscopic Foraminifera, placed by De Blainville in a division of 
the genus Rotalites. 

COSTATED. Ribbed, as Cardium Angulatum, fig. 123. 

COSTELLARTA. A sub-genus of the genus Tiara, Sw. (Mitra.) 
C. rigida. Swainson, Zool. 111. 1st series, pi 29. 

COWRY. A common name for shells of the genus Cypraea. 






CRASSIPEDES. \2. r > 

CRANIA. (Cranium, a skull.) Fain. Rudistes, Lam. Order, 
Pallio-branchiata, Bl. — Descr. Inequivalve, equilateral, irregular, 
sab-quadrate j upper valve patelliform, conical, with the umbo 
near the centre; lower valve attached by its outer surface; mus- 
cular impressions, 4 in each valve; two large, posterior, dis- 
tant; two small, near to each other, central. No hinge teeth; 
no ligament. — Ohs. This genus properly belongs to the Brachio- 
poda, Lam. It differs from Orbicula in the mode of attachment, 
which in the latter, is by a byssus passing through the lower 
valve, and not by the valve itself. Hipponyx has only two mus- 
cular impressions in each valve. The name of this genus is de- 
rived from the inner surface of the attached valve, which presents 
a remarkable resemblance to the facial portion of a human skull. 
This appearance is caused by the situation and elevated edges of 
the muscular impressions. Fig. 197- Coasts of Britain and 
Mediterranean. 

CRASSATED. (Crassus, thick.) Used to express a thickness in 
the substance of a shell. Ex. Glycimeris, fig. 67. 

CRASSATELLA. Lam. (Crassus, thick.) Fam. Mactracea, Lam. 
Conchacea, Bl. — Descr. Equivalve, inequilateral, close, thick, 
rounded anteriorly, rostrated posteriorly, with denticulated mar- 
gins, smooth, or ribbed transversely ; hinge with a triangular pit 
containing the cartilage, two anterior cardinal teeth, and a pos- 
terior depression in one valve ; one anterior tooth and a slight 
anterior marginal elevation, and a posterior elevation in the other 
valve. Muscular impressions distant, strongly marked. Palleal 
impression not sinuated. — Obs. The few recent species known 
are marine, several being brought from the coasts of New Holland. 
Fossil species are found in Calcaire-grossier and London clay. 
The Crassatella are known from the Veneres, &c, by the liga- 
mentary pit in the hinge, and from Lutraria and Mactra by the 
thickness and closeness of the shell. Fig. 84, C. rostrata. 

CRASSINA. Lam. Astarte, Sow. 

CRASSIPEDES. Lam. [Crassus, thick ; pes, foot.) The first 
section of the order Conchifera Dimyaria, Lam. In this section 
the foot of the animal is thick, and the shell gapes considerably. 



126 CREPIDULA. 

It is divided into the families Tubicolae, Pholadidse, Solenidae, 
and Myaria. Fig. 44 to 76. 

CRASSISPIRA. Sw. A genus separated from Coltjmbella, 
Auct. for which Mr. Swainson quotes " Pleurotoma Bottse, 
Auct." Crassispira fasciata, Sw. Lardn. Cyclop. Malac. p. 313. 

CRENATED. (Crena, a notch.) Applied to small notches, not 
sufficiently raised or defined, to be compared to teeth. Ex. The 
hinge of Iridina, fig. 150. 

CRENATULA. Lam. Fam. Malleacea, Lam. Margaritacea, Bl. 
— Descr. Compressed, foliated, irregular, sub-equivalve, inequi- 
lateral, oblique; umbones terminal; hinge linear, nearly straight, 
with a series of excavations, containing the cartilage, while the 
intervening ridges are covered with the ligament, properly so 
called. Muscular impression oblong, indistinct. — Obs. This 
genus is known from Perna by the hinge, which in the latter is 
composed of a series of regular, straight, ligamentary grooves 
placed across it. In Crenatula also there is no passage for the 
byssus, as in Perna. C. Mytiloides, fig. 168. Coasts of the Red 
Sea. 

CRENULATED. Finely crenated or notched. 

CREPIDULA. Lam. (Crepidula, a little slipper.) Fam. Calyp- 
tracea, Lam. and Bl. — Descr. Oval, irregular, patelliform; apex 
lateral, incurved, or sub-spiral; external surface convex, smooth, 
ribbed, waved, or covered with spines; interior concave, smooth, 
with a flattish septum reaching nearly half across the cavity ; 
epidermis light brown. — Obs. The difference between this genus 
and Calyptraea is that in the latter, the septum is more free from 
the sides of the shell, so that, instead of forming a regular plate, 
covering half the aperture, it assumes a variety of shapes, and 
in some is cup-shaped, in others forked, and in some forms a 
little angular shelf. Indeed, the variations are so numerous that 
I think it would be better to throw the two genera into one, and 
then divide them into smaller groups. Some species of Calyp- 
trsea are farther removed from each other with respect to the 
characters of the septum and general form of the shell, than 






CRISTACEA. 127 

they are from the Crepidulae. Fig. 239. Mediterranean, North 
and South America, East and West Indies, New South Wales, &c. 

CREPEDULINA. Bl. Cristellaria, Lam. Microscopic. 

CRESEIS. Ranz. Order, Pteropoda, Lam —Descr. Thin, fra- 
gile, transparent, pyramidal, pointed ; with a dorsal ridge pro- 
duced into a point at the edge of the aperture. — Obs. The species 
found in the Mediterranean is named C. Spinifera (fig. 222), 
from its resemblance to a thorn. 

CREUSIA. Leach. (Creux, se. Fr. a cavity.) Fam. Balanidea, 
Bl. Order, Sessile Cirripedes, Lam. — Descr. A depressed cone, 
consisting of four valves, supported upon, and jointed to, a cup- 
shaped cavity formed in the Madrepores, in which it resides. 
Aperture quadrilateral, closed by an operculum of four valves. — 
Obs. This genus is distinguished from Pyrgoma, which is sup- 
ported on the edge of a similar cup-shaped cavity, by the paries 
being composed of four valves, whereas in Pyrgoma, it consists 
of a single piece. Fig. 28, C. Gregaria. East Indies. 

CRICOSTOMATA. Bl. The second family of A siphonibranchiata, 
Bl. It is thus described : " shell equally (with the animal) va- 
riable in general form, but of which the aperture, always nearly 
round, is completely closed by the shelly or horny operculum ; 
whorls few, and apex sublateral." This family agrees in some 
measure with the family Turbinacea of Lamarck, and with the 
genus Turbo in the system of Linnseus. It contains the genera 
Pleurotomaria, Delphinula, Turritella, Proto, Scalaria, Vermetus, 
Siliquaria, Magilus, Valvata, Cyclostoma, and Paludina. 

CRIOCERATITES. A genus composed of species of Ammonites, 
with disconnected whorls. C. Duvallii, fig. 482. 

CRIOPUS. Poli. Crania, Auct. 

CRISTACEA. Lam. The third family of Polythalamous Cephalo- 
poda, Lam. This family is described as including shells of the 
following characters : — " Multilocular, flattened, nearly ren if orm ; 
the chambers gradually increasing in length, as they approach 
the outer arched margin, and appearing to revolve round an ec- 
centric, more or less marginal axis. The Cristacea contain the 
genera Renulina, Cristellaria, and Orbiculiria." 



128 



CUCULLiEA 



CRISTACEA. Bl. The third family of Polythalamia, Bl. con- 
taining the genera Crepidulina, (Cristellaria, Lam.) Oreas and 
Linthuris. 

CRISTARIA. Schum. Dipsas Plicatus, Leach. Anodon tuber- 
culatus, Fer. 

CRISTELLARIA. Lam. Crepidulina, Bl. Fam. Cristacea, 
Lam. and BL — Descr. Semidiscoidal, chambered; whorls con- 
tiguous, enlarging progressively ; spire eccentric, sublateral ; 
septa imperforate. Microscopic. 

CRYPTA. Humph. Crepidula, Lam. 

CRYPTELLA. Webb. (Kpwr™, to conceal.) Testacellus Am- 
biguus of Ferrusac. Published in Sowerby's Genera of Shells as 
Parmacella calyculata. — Descr. A small patelliform shell, with 
a very short papillary spire ; and the aperture irregularly ex- 
panded. Fig. 256. Canary Islands. 

CRYPTOCONCHUS. BL A genus composed of species of Chiton, 
the valves of which are covered by the integument, as Chiton 
porosus of Burrows Ch. amiculatus of Pallas. 

CRYPTODIBRANCHIATA. Bl. The first order of the class Ce- 
phalophora, Bl. containing families of molluscous animals des- 
titute of shells. 

CRYPTOSTOMA. Bl. Differs from Sigaretus, Lam. principally 
in the soft parts of the animal. De Blainville remarks that he is 
acquainted with only two species (from the Indies), which he 
can with decision refer to the genus, but he thinks that many of 
the Lamarckian Sigareti may very probably be found to belong 
to it, as soon as the soft parts shall be known. The species which 
he figures is Cryptostoma Leachii. (Manuel de Malacologie, pi. 42. 
fig. 3.) 
CTENOCONCHA. Gray. Described as having many characters in 
common with the Solens, the teeth like Nucula, but the cartilage 
entirely external. Solenella, Sow. ? 
CUCULLiEA. Lam. (Cucullus, a hood.) Fam. Arcacea, Lam. — 
Descr. Sub-quadrate, nearly equivalve, sub-equilateral, deep ; 
hinge rectilinear, with a series of angular teeth, small near the 
umbones, larger and more oblique towards the extremities ; um- 



CURVULA. 129 

bones separated by a flat external area, on which the ligament is 
spread. Anterior muscular impression produced into a sharp- 
edged plate or ledge, projecting from the side of the shell. 
Posterior muscular impression flat and indistinct. — Obs. This 
genus very much resembles Area in general form, but differs in 
the oblique, lengthened character of the remote teeth, and in the 
singularly prominent edge of the muscular impression. China. 
Fig. 133, C. Auriculifera. 

CUCUMIS. Klein. Marginella, Auct. 

CULTELLUS. Species of Lutraria, Lam. which have the urn- 
bones placed near the extremity of the shell. Ex. L. Solenoides, 
fig. 7S. 

CUMA. Humph. Fusus and Fasciolaria, Lam. 

CUMINGIA, Sow. Fam. Mactracea, Lam. — Descr. Equivalve, in- 
equilateral, transverse, rounded anteriorly, subrostrated posteriorly. 
Hinge with a central spoon- shaped cavity in each valve, contain- 
ing the cartilage; a very small anterior cardinal tooth in each 
valve; two lateral teeth in one valve, none in the other : muscular 
impressions two in each valve, distant ; palleal impression with a 
very large posterior sinus. — Obs. The species known at [present 
are found in sand, in the fissures of rocks in Tropical climates. 
They resemble Erycina in general form and character, but differ 
in having the internal cartilage placed in a prominent spoon- 
shaped process, while that of Erycina is contained in a hollow 
which sinks under the umbones. This genus should be placed 
near Amphidesma. Cumingia mutica, fig. 87. 

CUNEIFORM. (Cuneus, a wedge.) Wedge-shaped, as Donax, 
fig. 108. 

CUNEUS. Megerle. Venus Meroe, Linn, and similar species. 

CUNICULA. Sw. A sub-genus of Uniones, thus described : — 
" Ovate, oblong; bosses thick, but depressed; cardinal teeth mode- 
rate. C. planulata, patula, rubiginosa, secura, purpurascens." 

CURVED. Arched or bent. Ex. Dentalium, fig. 2. 

CURVULA. Rafinesque. A fossil imperfectly described as dif- 
fering from Pinna, in being inequivalve. 



130 CYCLOSTOMA. 

CUV1ERIA. Ranz. (Baron Cuvier.) Class, Pteropoda, Lam. 
— Descr. Thin, transparent, glassy, cylindrical, rounded and in- 
flated at the closed extremity, compressed towards the opening, 
so as to render it oval. This genus differs from Vaginula in being 
rounded, instead of pointed, at the lower extremity. Mediter- 
ranean. Fig. 223, C. Columella. 

CYCLAS. Brug. Fam, Conques Fluviatiles, Lam. Conchacea, 
Bl. — Descr. Orbicular, thin, subovate, ventricose, sub -equilateral, 
equivalve ; cardinal teeth minute, one more or less complicated in 
the left valve, two diverging in the right ; lateral teeth elongated, 
compressed, laminar, acute, doubled in the left valve ; ligament 
external ; epidermis thin, horny. — Ohs. The Cyclades are vivi- 
parous, and abound in ditches, ponds, slow streams, &c. in 
Europe and North America. The genus Pisidium has been sepa- 
rated on account of a difference in the animal, and may be known 
from Cyclas by being less equilateral, and the anterior side being 
the longest. Fig. Ill, C. Rivicola. 

CYCLOBRANCHIATA. Bl. The third order of the second sec- 
tion of Paracephalophora Monoica, Bl. containing no genera of 
Testaceous Mollusca. 

CYCLOCANTHA. Sw. A genus of "Trochidse," consisting of 
Turbo stellaris and T. Calcar, and corresponding with the genus 
Calcar, Montf. 

CYCLONASSA. Sw. A genus of "Nassinse," Sw. consisting of 
Nassa Neritoidea, and corresponding with the genus Cyclops, 
Montf. 

CYCLOPHORUS. Montf. A generic name proposed for those 
species of Cyclostoma, Auct. which have an umbilicus. C. In- 
volvulus, fig. 304, would be the type of this genus. 

CYCLOPS. Montf. Nassa Neritoidea, Auct. fig. 424. 

CYCLOSTOMA. Auct. (kvkKoq, cyclos, round ; orcyia, stoma, 
mouth.) Fam. Colimacea, Lam. Cricostomata, Bl. A genus 
of land shells varying in shape from that of Pupa to that of a 
flat orb ; the aperture is generally circular and the peritreme un- 
interrupted, thickened and sometimes reflected, the operculum is 



CYMBA. 131 

shelly and spiral. Two other genera of land shells are provided 
with opercula, and consequently might he confounded with this 
genus. In Ilelicina, the operculum is concentric and the peri- 
treme is not continuous ; while in the small genus hitherto almost 
unknown of Pupina, the peritreme is not continuous and there is 
a glassy enamel over the whole of the external surface. In the 
plates we have represented, C. ferrugineum, fig. 303 ; C. invol- 
vulus, fig. 304. 

CYCLOTUS. Guild. A sub-genus of Cyclostoma, consisting of 
those species which are discoidal, as C. Planorbulum. Fig. 

CYLINDER. Montf. Conus textile, Auct. (fig. 461) and other 
species having a cylindrical form. 

CYLINDRELLA. Sw. A genus of the family "Ovular," Sw. 
composed of cylindrical species of Ovulum ? The wood-cut 
illustrating this genus has the appearance of a Bulla. 

CYLINDRICAL. (KvXivtyog, a cylinder.) This like other ma- 
thematical terms is used with great latitude by Conchologists, and 
applied to any shell the sides of which are nearly parallel, with 
the extremities either rounded, flat, or conical. Ex. Oliva, fig. 457. 

CYLLENE. Gray. Fam. Purpurifera, Lam. — -Deser. Oval, thick, 
with a short acute spire ; an oval aperture terminating anteriorly 
in a slight emargination, posteriorly in a short canal ; a fold at 
the lower end of the body whorl ; outer lip thick, striated within ; 
angle of the whorls tuberculated. — Obs. This genus of small 
marine shel/s resembles Voluta in general character, but differs 
in having a smooth columella without folds. Recent, Pacific 
Ocean ; Fosil, London clay. Fig. 425. 

CYMBA. Brod. (Cymba, a boat or skiff.) Fam. Columellaria, 
Lam. — Bescr. Smooth, ventricose, with a very short, mammillated, 
rude spire ; and a very large, wide aperture, terminated anteriorly 
in a deep emargination ; posteriorly in a flat ledge, which sepa- 
rates the outer lip from the body whorl ; columella with three or 
four oblique, laminar, projecting folds, terminating in a point ; 
outer lip thin, with its edge sharp; epidermis smooth, brown, 
covered partly or entirely by the glassy enamel, which, com- 
ic 2 



132 CYPR/EA. 

mencing with the outer lip, spreads over the body of the shell. — 
Obs. These very elegant shells, found in Africa, are distinguished 
from the true Volutes by the shapeless, mammillated apex of the 
short spire, by the large size of the aperture, and by the horizontal 
ledge which separates the outer lip from the body whorl. The 
genus Melo, also separated by Mr. Broderip from the Volutes, 
agrees with Cymba in some respects, but differs in the regularity 
of the spire. Fig. 434, C. Porcina. 

CYMBIOLA. Sw. The generic name for a group of Volutes, de- 
scribed as " armed with spinous tubercules, sometimes smooth, 
but never ribbed ; spiral whorls gradually diminishing in size, but 
not distorted ; apex thick and obtuse ; pillar with four plaits." 
Mr. Swainson remarks that this genus is chiefly distinguished by 
the obtuse, but not irregular spire. The typical species are stated 
to be V. Rutila and V. Vespertilio, fig. 433. Tropical. 

CYMBULIA (Dim. from Cymba.) Fam. Pteropoda, Lam. An 
extremely light, cartilaginous covering of a molluscous animal, so 
named from its similarity in shape to a boat. We mention it 
here on account of its similarity to the shelly or glassy covering 
of other Pteropods, to which, although membranaceous, it is evi- 
dantly analogous. The Cymbulise are found in the Mediterranean. 

CYPRiEA. Auct. Fam. Enroulees, Lam. Angyostomata, Bl. — 
Bescr. Oval or oblong, ventricose, convolute, covered by an 
enamel, generally smooth and shining. Spire short, nearly 
hid. Aperture long, narrow, terminating in a short canal at both 
extremities. Outer lip dentated, thickened, inflected. Inner lip 
dentated, thickened, reflected over part of the body whorl. — Obs. 
These shells are so distinguished by the two rows of teeth ar- 
ranged on each side of the aperture ; the thickened front formed 
by the inner and outer lips ; and the enamel deposited over the 
back of the shell from the mantle of the animal which envelopes 
it, that there is no danger of confounding them with any other 
genus, except in a young state. Before they have arrived at the 
full growth, the front is not thickened, and the outer lip is thin, 
not inflected, nor are the teeth formed. In this state the shell 



CYPRiECASSIS. 133 

resembles, in some degree, an Oliva. Some species are striated, 
ribbed, or tuberculated, but the generality are smooth. Most 
species belong to tropical climates, only one to Great Britain. 
The C. Moneta is current as money in some parts of Africa, and 
many species are worn as ornaments by the South Sea Islanders. 
The colouring in most species is exceedingly rich, and arranged in 
every variety of spots, patches, rings, lines, bands and clouds. 
The species most esteemed by collectors are C. Mappa, C. Testu- 
dinaria, C. Pustulata, C. Aurora, C. Princeps, of which only two 
specimens are known, C. Leucodon, &c. See also Cyprseovulum, 
Trivea and Luponia. The fossil species are principally from the 
Calc-grossier, the London Clay, Crag, &c. Fig. 445 to 450. 
The latest revision of this genus has been effected by Mr. G. B. 
Sowerby, sen., who has published a complete catalogue in his son's 
Conchological Illustrations. This catalogue enumerates 130 
species, the whole of which are figured in parts 1 to 8, 101 to 
131 of the above mentioned work. 
CYPR^ECASSIS. Stutch. (Cypreea and Cassis.)— Descr. Shell, 
when young, striated, reticulated, or tuberculated ; outer lip 
simple : when mature, outer lip involute and toothed ; columella!- 
lip also toothed ; aperture straight, anteriorly terminated by a 
recurved canal, posteriorly by a shallow channel. Animal with 
the mantle bilobed ; operculum none. — Obs. The reasons given 
for separating this genus from Cassis, are, 1st, That the shells of 
the latter have an operculum, while those of the proposed genus 
have none. 2nd, That the Cyprsecassides do not form a com- 
plete, thickened lip, before the full period of their growth, like 
the Cassides. 3rd, That the Cypreecassides have no epidermis. 
The species mentioned as probably belonging to Cyprsecassis are 
C. rufa, the type ; C. coarctata, and C. Testiculus, Auct. The 
establishment of this genus has been opposed on the ground that 
indications of epidermis are discoverable in some specimens of C. 
rufa ; that some specimens of the same species and Testiculus 
have been examined, and found to have formed slightly thickened 
and dentulated outer lips at very early periods of growth, while 
many of the other Cassides are destitute of varices, and that an 



134 CYPRINA. 

operculum of C. coarctata was brought to this country by Mr. 
Cuming. It is probable, however, that an increased knowledge 
of facts might go far to establish the separation. C. Testiculus, 
fig. 412. 

CYPR^EADIA. Sw. A genus of the family " Cyprseidse," Sw. 
thus described :— " Cyprseform ; the base contracted ; the body 
whorl not flattened beneath ; shell cancellated ; aperture of equal 
breadth throughout ; a few thickened, short teeth on the pillar ; 
lip at the base, which is not internally concave. C. cancellata, 
Sw. Fossil only, differing from Trivea in its contracted base, in 
the inequality of its aperture, and the equal convexity of the 
inner lip within." (Sw. Lardn. Cyclop. Malac. p. 325.) Cyprse- 
dia, fig. 564. 

CYPRiELA. Sw. A genus formed for the reception of Ovulum 
verrucosum, Auct. which has a circular depression at each ex- 
tremity. It is the same as the genus Calpurnus of De Montfort. 
Ovulum verrucosum, fig. 441. 

CYPRM)VULUM. Gray. A genus of Cyprseidee thus described, 
" shell like a cowry, but front end of columella covered with 
regular cross-ribs, like the rest of the base, internally produced 
into an acute toothed ridge. Shell pear-shaped, cross-ridged.' ' 
C. capense, fig. 444. South Africa. 

CYPRICAKDIA. Lam. Fam. Cardiacea, Lam. — Bescr. Equi- 
valve, inequilateral, subquadrate, transversely elongated, with 
the anterior side very short ; hinge with three cardinal teeth and 
one remote lateral tooth in each valve ; muscular impressions 
two in each valve ; ligament external. — Obs. This genus is 
distinguished from Cardita by the three cardinal teeth. The 
mollusca of this genus are marine. C. angulata, fig. 125. Pacific 
Ocean. 

CYPRINA. Lam. Fam. " Conques Marines," or Marine Con- 
chacea. — Descr. Equivalve, inequilateral, sub -orbicular; umbones 
curved obliquely ; hinge with three diverging cardinal and one 
remote lateral teeth in each valve ; ligament external ; muscular 
impressions two in each valve ; palleal impression having a slight 
posterior sinus j epidermis thick, rough brown.— Obs. The Cy- 



CYTHEREA. 135 

prinae belong to the Northern hemisphere. The recent ispecies 
are not numerous. Fossil species are found in the tertiary de- 
posits. Cyprinamay be known from Venus by the remote lateral 
tooth and the thick epidermis. C. vulgaris, fig. 116. 

CYRENA. Auct. Fam. Fluviatile Conchacese, Lam. Conchacea, 
Bl. — Descr. Suborbicular, equivalve, inequilateral, ventricose, 
corroded at the umbones, thick, covered with a thick epidermis ; 
hinge with three cardinal and two remote lateral teeth in each 
valve. Muscular impressions two in each valve ; palleal impres- 
sion not sinuated. — Obs. This genus is distinguished from Venus, 
Cytherea and Cyprina, by having two remote lateral teeth ; and 
from Cyclas by the thickness of the shell. This genus is mostly 
fluviatile; the recent species are tropical, and the fossil are found 
in the newest formations. Fig. 113, C. fuscata. 

CYRENELLA. Desh. See Cyrenoides. 

CYRENOIDES. Joannis. Cyrenella, Desh. Fam. Conques 
Fluviatiles, Lam. — Descr. Equivalve, subequilateral, ventricose, 
thin, covered with a reddish brown epidermis, corroded at the 
umbones, with a slight posterior fold. Hinge thin, with three 
diverging cardinal teeth in each valve, and a very slight posterior 
fold in the right valve. Ligament not very tumid.' — Obs. This 
fresh-water shell differs from Cyclas and Cyrena in the want of 
lateral teeth, and from the latter in the thinness of the shell. 
Fig. 114. 

CYRTIA. Dalman. (Kvprog, curtos, gibbose.) Fam. Brachiopoda, 
Lam. — Descr. " Hinge rectilinear ; with the back elevated into 
a semicone or half-pyramid, the cardinal side perpendicularly 
plane" — Obs. This genus of fossil Brachiopoda forms part of 
the genus Spirifer, Sow. C. exporrecta, (Anomites exporrecta, 
Nonnull.) fig. 204. 

CYTHEREA. Lam. Fam. " Conques Marines," Lam.— Descr. 
Equivalve, inaequilateral, oval, lenticular, or sub-trigonal ; hinge 
with two or more short, diverging cardinal teeth, and one an- 
terior approximate lateral tooth in each valve. — Obs. The Cy- 
therese are distinguished from the Veneres by the lateral tooth. 
C Meretrix, fig. 11/, and 117, a. b. c. d. 



136 DELPHINULA. 

DACTYLUS. Humph. Marginella, Auct. 

DARACIA. Gray. A subgenus of Pyrgoma, including a species 
which is remarkable for the irregularity of its form. It grows 
upon a species of Monticularia, and the margin takes the shape 
of the lobes by which it is surrounded. The aperture is large, 
and completely closed by the operculum. Daracia (Pyrgoma) 
Monticulariee, fig. 489, 490. 

DATE. A common name given to shells of the genus Pholas, on 
account of their cylindrical form and consequent resemblance to 
the fruit. For the same reason the name Pholas Dactylus has 
been given by Naturalists to the species which we represent, fig. 66. 

DEAD SHELL. A term used among collectors to signify that the 
shell has been exposed on the sea- shore after the animal has 
ceased to live. A shell in this condition is worn down by at- 
trition, and loses its beauty and brilliancy of colouring by being 
subject to the action of salt water. A dead shell may be known 
by a certain hoary whiteness spread over its surface. 

DECACERA. Bl. The second family of the order Cryptodibran- 
chiata, Bl. containing the genera Calmar and Sepia, which have 
no shells. 

DECADOPECTEN. Ruppell. Pecten Plica, Linn. Fig. 172, 
having a plicated hinge. 

DECOLLATED. (Decollari, to be beheaded.) The apex or nu- 
cleus of some shells being composed of a more fragile substance 
than the rest, has a tendency to fall off. The reason of this pro- 
bably is that the animal withdrawing from that part, leaves it 
unprotected. When it falls off, the hole is stopped up by a 
septum filling the cavity of the volution, so as to exclude the 
air : the shell is then said to be decollated. Ex, Bulinus decol- 
late, fig. 289. 

DECUSSATED. Intersected by striae crossing each other. +Ex. 
Rissoa, fig. 346. 

DELPHINULA. Montf. (Delphinus, a dolphin.) Fam. Scalariens, 
Lam. Cricostomata, Bl. — Descr. Orbicular, depressed, thick, 
rugose ; whorls few, angulated, branched at the angles ; aperture 
pearly, rounded or sub-quadrate ; peritreme continuous, thick- 



DEXTRAL. 137 

ened ; operculum horny, composed of numerous whorls. — Obs. 
Several fossil species are found in the tertiary deposits. D. 
laciniata, fig. 352. Recent species belong to tropical climates. 

DELTHYRIS, Dalman. Fam. Brachiopoda, Lam. — Descr. Hinge 
more or less rounded, with distant umbones ; both valves convex ; 
with the umbo of the largest rostrated and deltoid, with a hollow. 
This genus forms part of the genus Spirifer, Sow. Fig. 205. D. 
Plycotes, Dalman. 

DELTOID. (A, delta.) Triangular. 

DENDOSTREA. Sw. (Aevdpov, dendron, tree ; oarpsov, ostreon, 
oyster.) Ostrea Crista-galli, and other species which are attached 
to stems of sea-weed and corallines, by means of arms thrown out 
from the inner surface of the lower valve. Fig. 181, Ostrea 
Folium. 

DENTALIUM. Auct. {Dens, a tooth.) Fam. Maldania, Lam. 
Order, Cirrobranchiata, Bl. — Descr. Tubular, arched, increasing 
in size towards the anterior extremity, open at both ends ; small 
aperture sometimes having a lateral fissure ; large aperture round ; 
external surface ribbed, striated or smooth. — Obs. The well 
known shells composing this genus are shaped very much like an 
elephant's tusk, and are not liable to be confounded with any other 
genus. The fossil species are sometimes termed Dentalithes, 
from dens, a tooth, and lithos, a stone. The Dentalia, being true 
molluscs, are not rightly placed among the Annelides. Fig. 2, 
D. octogonum. Found on sandy shores in most climates. 

DENTATED. Having teeth or raised points. 

DENTICULATED. (Denticulatus, Lat.) Having little teeth or 
raised points. 

DEPRESSED. Flattened, pressed down, as the spires of some 
shells. 

DEXTRAL Spiral Shells. Place the point of a spiral shell towards 
the eye, with its mouth downwards ; if, as in most instances, the 
aperture be on the right side of the axis, it is a dextral shell, if 
otherwise, it is sinistral or reversed. Balea (fig. 296), and 
Clausilia (fig. 295), are examples of reversed shells. 

DEXTRAL Valve. Take a bivalve shell closed, place it before the 



138 DIFFUSE. 

eye, with the umbones uppermost, and the posterior side, which 
may be known by the ligament towards the observer, whose right 
side will then correspond with the right valve of the shell. 

DIADEMA. Ranz. Coronula Diadema, Auct. fig. 17. 

DIANCHORA. Sow. Fam. Pectinides, Lam. Order, Pallio- 
branchiata, Bl. — Bescr. Inequivalve, attached, oblique, sub- 
triangular ; attached valve, having an opening in the place of the 
umbo ; the other valve auriculated, with an obtuse umbo ; hinge 
without teeth. — Obs. The green sand fossils contained in this 
genus differ from Plagiostoma in being attached. Fig. 175, D. 
striata. 

DIAPHANOUS. (Am, dia, through ; <pairo), phaino, to shine.) 
Transparent. 

DIAPHRAGM. (Eiacppayfia, a partition.) This term is applied 
to the septa, by which the chambers of multilocular and other 
shells are divided from each other. 

DICERAS. Lam. (Ave, dis, double ; Kepag, ceras, horn.) 
Fam. Chamacea, Bl. and Lam. — Bescr. Inequilateral, inequi- 
valve, attached by the point of the umbo of the larger valve ; 
umbones prominent, spirally twisted and grooved ; hinge with 
one large thick tooth in the larger valve ; muscular impressions, 
two in each valve. — Obs. The prominent spiral umbones, which 
give rise to the name of this genus, with the circumstance of its 
being attached by the point of one of them, is sufficient to 
distinguish it from any other, although it appears to approach 
Isocardia in some characters. In others it will be found still 
more nearly to resemble Chama. In fact, from being attached 
and irregular, the shells composing this genus have been consi- 
dered as Chamse with produced umbones. The singular fossil 
shells composing this genus, are found in granular limestone, 
near Geneva and in Normandy. Fig. 154, D. perversum. 

DIDONTA. Schum. Saxicava. Auct. 

DIFFUSE. (Difundo, to spread out, to dilate.) A term applied 
to the aperture of a univalve shell, when it is spread out or 
widened into a flat surface, or digitations. Alated is another 
term used to express the same character. Thus, the shells be- 



DISCONTINUOUS. 139 

longing to the family of Alatge, in the system of Lamarck, are 
diffuse in the outer lip. Fig. 402 to 40G. 

DIGITATED. (Digitus, finger.) Branched out in long points, as 
Ricinula, fig. 413. 

DILATED. Expanded, spread. This term has the same applica- 
tion as diffuse and alated, explained above. The outer lip of 
Rostellaria Columbaria, fig. 403 (Hippochrenes, Montf.), will 
serve as an example. 

DIMORPHINA. D'Orb. A genus of microscopic Foraminifera. 

DIMYABJA. (Ate, dis, double ; pvov, my on, muscle.) The first 
order of Conchifera, Lam. including those molluscs which have 
two adductor muscles, and consequently two muscular impressions 
in each valve. The Conchifera Dimyaria are divided into Cras- 
sipedes, Tenuipedes, Lamellipedes, and Ambiguee, fig. 44 to 
155. 

DIOICA. Bl. The first division of the class Paracephalophora, 
Bl. It is divided into the orders Siphonobranchiata and Asiphoni- 
branchiata, Bl. 

DIPLODON. Spix. Hyria Syrmatophora, Lam. fig. 144, and 
Unio multistriatus, Lea, are doubtfully quoted by Lea as belong- 
ing to this apparently ill-defined genus of Nayades. 

DIPSAS, Leach. A genus or sub-genus of Nayades, the distinc- 
tive character of which is " having a linear tooth under the dorsal 
edge." D. plicatus, fig. 142. 

DISCINA. Lam. Orbicula, Auct. 

DISCODOMA. Sw. A sub-genus of Lucerninse, Sw. (Helix), thus 
described, ' ' teeth none ; aperture angulated ; the inner lip nearly 
obsolete ; the outer only slightly thickened ; margin carinated." 

DISCOIDAL. (Discus, a circular plane.) A spiral shell is said to 
be discoidal, when the whorls are so horizontally convolute as to 
form a flattened spire. Ex. Planorbis, fig. 311. Orbulites 
Discus, fig. 4/9. 

DISCOLITES. Montf. A genus of microscopic Foraminifera. 

DISCONTINUOUS. Interrupted. Ex. The siphon of Nautilus 
is discontinuous, i. e. its termination in one chamber does not 
reach to its commencement in the next. The varices of Triton, 



140 DONAX. 

occurring in different parts of the whorls, do not form the con- 
tinuous ridges which characterize the generality of the Ranellse. 

DISCORBITES. Lam. A genus of microscopic Foraminifera. 

DISTANT. The teeth on the hinge of a bivalve shell are said to be 
distant when they are remote from the umbones. 

DIVARICATED. Diverging, meeting in a point, as the teeth on 
the hinge of Placuna, fig. 184. 

DOLABELLA. Lam. (Dim. from Dolabra, a hatchet.) Fam. 
Aplysiacea, Lam. and Bl. — Descr. Hatchet-shaped, arched, 
covered with a horny epidermis ; posteriorly attenuated, thick- 
ened, sub-spiral, anteriorly plane, broad, thin ; posterior margin 
reflected. — Obs. The two or three species of Dolabella known are 
inhabitants of the Indian Ocean. They were placed by Linnseus 
in his very convenient genus Bulla, under the name B. dubia. 
Fig. 255, Dolabella Rumphii. 

DOLIUM. D'Argenville. (a tun.) Fam. Purpurifera, Lam. En- 
tomostomata, Bl. — Descr. Thin, ventricose, oval, or globular, 
with a short spire ; large aperture terminating in a reflected canal, 
and spirally ribbed or grooved external surface ; outer lip cre- 
nated ; inner lip reflected over part of the body whorl, which 
terminates in a tumid varix ; epidermis light, horny. Mediter- 
ranean and East Indian. — Obs. This genus is distinguished from 
Cassis by the outer lip, which is not reflected. The species which 
are not so rotund as the others, as D. Perdix, Auct. have been 
separated under the name Perdix, as generic. Fig. 420, Dolium 
Maculatum. 

DONAX. Auct. Fam. Nymphacea, Lam. Conchacea, Bl. — Descr. 
Equivalve, inequilateral, trigonal, with the anterior side short, 
straight, plane ; the posterior side elongated, drawn to a narrow, 
rounded termination ; hinge with two cardinal teeth in one valve, 
one in the other, and one or two, more or less remote lateral teeth ; 
ligament external ; muscular impressions two in each valve ; pal- 
leal impression sinuated posteriorly. — Obs. The Capsoe have not 
the crenated margins, the short anterior side, and the distinct late- 
ral teeth, which characterize the Donaces. Some species of Erycina 
resemble Donax in general form, but are at once distinguished 



EBURNA. 



141 



by the ligamentary pit in the hinge. Sandy shores in all climates. 
Fig. 108, D. cuneatus. 

DORSAL. A dorsal shell is one placed upon the back of the ani- 
mal. The dorsal margin of a bivalve shell is that on which the 
hinge is placed ; the opposite margins are termed ventral. The 
dorsal surface of a spiral univalve is that which is seen when the 
aperture is turned from the observer. The dorsal valve is the 
uppermost in Brachiopodous bivalves. The dorsal part of a 
symmetrical convolute univalve, such as the Nautilus and Am- 
monite is that part of the whorls which is at the greatest dis- 
tance from the spire, that is, the outer part of the whorls Thus 
the situation of the siphon is said to be dorsal when it pierces the 
septum near the outer edge of the whorls, The dorsal part of 
symmetrical conical univalves, such as Patella, is the upper part, 
on which the apex is placed. 

DORSALIA. Lam. (Dorsum, the back ) The first family of the 
order Annelides Sedentaria, Lam. containing the genera Areni- 
cola, not a shell, and Siliquaria, fig. 1, which is now considered 
as a true mollusc, and placed next to Vermetus. 

DOSINA. Schum. Venus Verrucosa, Casina, and similar spe- 
cies. Fig. 119, a. 

DREISSINA. Mytilus Polymorphs. Auct. fig. 159. This 
genus differs from Mytilus principally in the characters of the 
animal. The shell is characterized by a small septiform plate 
under the hinge within. Fluviatile, Europe and Africa. 

EBURNA. Lam. (Eburneus, ivory.) Fam. Purpurifera, Lam. 
Entomostomata, Bl. — Descr. Oval, thick, smooth, turrited, um- 
bilicated ; spire angulated, acute, nearly as long as the aperture ; 
aperture oval, terminating anteriorly in a canal, posteriorly in a 
groove ; outer lip slightly thickened with an anterior notch, 
which terminates in a spiral fold surrounding the body whorl ; 
umbilicus generally covered by the thickened columellar lip. — 
Obs. The beautiful shells called ivory shells, which originally 
constituted part of this genus, are now placed in the genus An- 
cillaria by authors. They differ from the present genus Eburna, 
in having the sutures of the spire covered with a polished enamel. 



142 ELEVATED. 

(A. glabrata, fig. 455,), The Eburnse resemble in some respects 
the genus Buccinum, but a glance at the figure will enable the 
reader to distinguish a true Eburna from all other shells. Fig. 
426 is Eburna Zeylanica. A catalogue of 9 species is given in 
part 20 of the Conchological Illustrations published by the 
Author, accompanied by figures of several species. 

ECHIDNIS. Montf. Described as a straight, chambered, annulated, 
fossil shell, computed from the extremely gradual increase in 
diameter of the fragments to be at least sixteen feet long. Found 
in marble from the Pyrenees. 

ECIIINELLA. Sw. A sub-genus of Monodonta. Sw. Malac. 
page 352. 

EFFUSE, (effiundo, to pour out.) The aperture of an univalve 
shell is said to be effuse when there is a notch in the margin 
which would suffer a liquid to escape, and thus prevent it being 
filled to the brim. 

EGEON. Montf. A genus of microscopic Foraminifera. 

EGERIA. Lea. (Contrib. to Geol. p. 49, pi. 1.) A genus of 
fossil bivalves, described as very variable in form, with or without 
lateral teeth, sometimes a crenated margin, &c. The only certain 
characters appear to be that they have two diverging cardinal 
teeth in each valve, one of which is bifid ; and an external liga- 
ment. Lea states that the Egerise should be placed between the 
Sanguinolarise and the Psammobige, which two latter genera have 
been united by Sowerby. Fig. 103, E. Triangulata, from the 
tertiary formation of Alabama. 

ELENCHUS. Humph. A genus composed of Trochus Iris, 
Auct. and other similarly formed species. It is the same as 
Cantharidus of Montfort. 

ELEPHANT'S TUSK. The common name given by dealers to 
shells of the genus Dentalium. Ex. D» octogonum, fig. 2. 

ELEVATED. A term which is applied by some conchological 
writers to the spire of an univalve shell when it consists of nu- 
merous whorls drawn out into a telescopic form. Other authors 
use the term elongated, or the more simple one ' long* to express 
the degree of elevation. 



EMARGINUIA. 143 

ELISMA. Lcacli. A sub-genus of Bulinus. B. acutus, Auct. Gray, 
Turton, p. 185. 

ELLIPSOLITHES. Montf. (EXke^tg, ellipsis, oval ; Xidog, Uthos, 
stone.) A genus composed of Ammonites, which instead of being 
regularly orbicular, take an elliptical or oval form. This cha- 
racter appears to be accidental, as some individuals of the same 
species, both of Nautilus and Ammonites, are round, while others 
are compressed into an oval form. 

ELLIPSOSTOMATA. Bl. (E\\ £ i^i £ , ellipsis, oyhI; areola, mouth.) 
The third family of the class Asiphonibranchiata, Bl. The shells 
of this family are described as of various forms, generally smooth ; 
the aperture longitudinally or transversely oval, completely closed 
by a horny or shelly operculum. This family contains the genera 
Rissoa, Phasianella, Ampullaria, Helicina, and Pleuroceras. 

ELLIPTICAL. (EMa+ts, ellipsis.) Oval. Applied to any shell 
or part of a shell, having that form. 

ELMINEUS. Leach. Order, Sessile Cirripedes, Lam. — Descr. 
Four unequal valves, arranged circularly side by side, forming a 
quadrate cone ; aperture large, sub-quadrate, irregular ; oper- 
culum composed of four valves, in pairs. — Obs. This genus differs 
from Conia in the structure of the shell, the latter being porous. 
Fig. 22, Elmineus Leachii. 

ELPHIDIUM. Montf. (Conch. Syst. t. 1. p. 15.) A genus of 
microscopic Foraminifera. 

EMARGINATED. (e, out ; margo, border.) Notched or hollowed 
out. Applied to the edges or margins of shells, when instead of 
being level they are hollowed out, as the outer lip of Oliva, fig. 
457, at the base, and the ventral margins of some bivalves. 

EMARGINULA. Lam. (e, out ; margo, border.) Fam. Calyp- 
tracea, Lam. Branchifera, Bl. — Descr. Patelliform, oblong or 
oval ; anterior margin notched or emarginated ; apex posteriorly 
inclined; muscular impressions wide. — Obs. Emarginula elon- 
gata, of some Authors, Parmophortjs of De Blainville is com- 
monly called the Duck's bill limpet, from its shape. The 
Emarginulae may be known from Patellae and other neighbouring 



144 ENTOMOSTOMATA. 

genera, by the notch or slit in the anterior edge. In the genus 
Rimula, Defr. fig. 243, this slit is near the apex, and does not 
reach the margin. Recent species occur in all climates, but are 
not numerous. Fossil species are still more rare, occurring in 
the Cale-grossier, Crag and Oolite. E. fissurata, fig. 241. 

ENA. Leach. A sub-genus of Bulinus. B. Lackhamensis. Mont. 

ENDOSIPHONITES. A genus composed of Ammonites, having 
the siphon close to the body whorl, fig. 476. 

ENDOTOMA. Rafinesque. A genus of microscopic Foraminifera. 

ENROULEES. Lam. See Convolute. 

ENSATELLA. Sw. A genus consisting of Solen ensis, Auct. 
fig. 60, and other species similarly curved. Genus Ensis, Schum. 

ENSIS. Schum. Solen ensis, Auct. and similar species. 

ENTALIS. Defr. Dentalium duplicatum, Bl. Pharetrium, 
Konig. This genus is described as a small tube, within a larger 
one, the smaller extremity of the inner tube projecting beyond 
that of the outer one. Deshayes, who describes this genus, ex- 
presses a conviction that the soft parts of the animal must be 
entirely different from those of the animal of Dentalium. The 
genus Pharetrium, as described by Konig in his "Icones Fos- 
silium Sectiles/' is evidently identical with Entalis. It is placed 
by him in the family of Pteropoda, but being a fossil shell, there 
is some difficulty in finding its place in the system. See plates, 
fig. 3. 

ENTELLITES. Fischer. A genus composed of species of Tere- 
bratula, Spirifer, and Productus, Auct. having the hinge 
large and the umbones short. Orthis ? Dalman. 

ENTIRE. (Integra.) Not interrupted, not emarginated. The peri- 
treme of a univalve shell is said to be entire when not interrupted 
by canals or by the body whorl. Ex. Cyclostoma, fig. 304. The 
palleal impression is entire, when continued without interrup- 
tion, or without a sinus. 

ENTOMOSTOMATA. Bl. The second family of the order Siphoni- 
branchiata, Bl. The shells of this family are described as dif- 
fering but little from those contained in the family of Siphono- 



EaUIVALVE. 145 

stomata of the same author, both with regard to the soft parts, 
and their testaceous covering. This family partly answers to 
the Purpuriferse in the system of Lamarck, and contains the 
genera Subula, Cerithium, Melanopsis, Planaxis, Terebra, Eburna, 
Buccinum, Harpa, Dolium, Cassidaria, Cassis, Ricinula, Cancel- 
laria, Purpura, Concholepas. 

EOLIDES. Montf. A genus of microscopic Foraminifera. 

EPIDERMIS. (E-riy epi, over or upon ; deppa, derma, skin.) The 
fibrous, horny, external coating of shells, called by the French, 
"Drop marin" or marine cloth. Lamarck objects to the name 
Epidermis because he does not consider the substance as answer- 
ing to the cuticle or scarf skin of the human body, but more 
analogous to the nails and hair. Gray calls it the Periostracum, 
from the membranous skin covering the bones of quadrupeds. 

EPIPHRAGM. The membranaceous or calcareous substance by 
which some species of molluscs close the aperture of the shell, 
when they retire within it to hibernate. When the animal 
wishes to come forth from his hiding-place, again to breathe the 
air, the edges of the Epiphragm are detached by a chemical pro- 
cess, so that it drops off. The name Hibernaculum has also been 
given to this covering. It must not be confounded with the 
operculum, which is a permanent portion of the shell, and is 
used as a door, fitted to the foot of the animal and moved at will 
to pen or close the aperture of the shell, whereas the Epiphragm 
is produced for the occasion from a mucous secretion of the ani- 
mal and dissolved at the edges when no longer wanted, when it 
drops off. . % 

EPISTYLA. Sw. A subgenus of the genus Helix. E. conical. 
Sw. Helix Epistylium, fig. 281. 

EPONLDES. Montf. A genus of microscopic Foraminifera. 

EQUILATERAL. (^Equus, equal ; latus, side.) Equal-sided." A term 
applied to bivalve shells, when a line drawn down perpendicularly 
from the apex would divide the shell into two equal parts. Ex. 
Pectunculus pilosus, fig. 134. 

EQUIVALVE. (iEquus, equal ; valva, a valve.) A term applied 



146 ETHERIA. 

to a bivalve shell when the valves are equal to each other in 
dimensions. 

ERATO. Risso. Fam. Convoluted Lam. — Descr. Ovate, more or 
less angulated, smooth or granulated, with a dorsal scar ; 
spire short ; aperture large, angulated, emarginated ; columella 
slightly crenated ; outer lip reflected, denticulated on the inner 
edge. Suture of the whorls covered with enamel. — Obs. This 
genus of shells resembles Marginella in form, but has no folds 
on the columella. Having a scar or groove down the back it may- 
be considered intermediate between Marginella and Cypraea. Fig. 
454, E. Maugerise. In the Author's Conchological Illustrations, 
seven species are enumerated and figured. 

ERUCA. Sw. A subgenus of Clausilia. Sw. Malac. p. 334. 

ERVILIA. Turt. A genus described as " oval, equivalve, equila- 
teral, closed. Hinge with a single erect tooth closing between two 
small diverging ones in the opposite valve : lateral teeth none. 
Ligament internal. E. nitens. Turt. Mya. nitens, Auct." 

ERYCINA. Lam. Fam. Mactracea, Lam. Conchacea, Bl. — Descr. 
Ovate or triangular, transverse, equivalve, inequilateral, smooth ; 
hinge with a ligamentary pit, two diverging cardinal and two lateral 
teeth in each valve ; muscular impressions two in each valve ; pal- 
leal impressions sinuated. East and West Indies and Mediterranean. 
— Obs. This genus is distinguished from Mactra and Lutraria by 
the cardinal teeth being placed one on each side of the ligamenti- 
ferous pit ; whereas in the last named genera they are both placed 
on the anterior side. Fig. 86, E. Plebeja. 

ERYTHR^IA. The ancient name for Cypr^a. 

ESCUTCHEON. The impression on the posterior dorsal margin 
of some bivalve shells. That on the anterior margin is named 
the lunule. The escutcheon is pointed out by the letter e in 
some of the figures of Cythereae. Fig. 1 17, a. b. c. 

ETHERIA. Lam. (JEther, air.) Fam. Chamacea, Lam. and 
Bl. — Descr. Irregular, inequivalve, inequilateral, foliaceous, 
pearly within, covered by an olive green epidermis without ; hinge 
callous,- undulated, destitute of teeth ; ligament partly external, 



FASCICULATED. 147 

partly internal, passing through the hinge on a somewhat raised, 
callous area in the lower valve. Muscular impressions elongated, 
two in each valve, united by a slender palleal impression. Rivers 
of Africa. — Obs. The irregular, unequal air-bubbles of the inner 
surface, whence this genus derives its name, are very brilliant in 
some species, and atone, in some measure, for the rugged 
ugliness of the exterior. In its irregular form, foliated structure, 
and toothless hinge, it resembles Ostrea, from which it differs in 
having two muscular impressions. Fig. 155, E. semilunata. 

EULIMA. Risso. Fam. Scalariens, Lam. — Descr. Elongated, 
smooth, pyramidal ; spire long, composed of numerous whorls ; 
apex acute, slightly tortuous ; aperture oval, rounded anteriorly, 
acute at the posterior union with the body whorl ; outer lip 
slightly thickened ; columella smooth. Fig. 347, E. labiosa, 
fig. 348, E. splendidula. A complete illustrated monograph of 
this genus of pretty shining little shells, consisting of 15 known 
species, is given in parts 52 and 53 of the Conchological Illustra- 
tions by the author. 

EUOMPHALUS. Sow. Fam. Scalariens, Lam,— Descr. Orbi- 
cular, planorbular spire, with three or four volutions, imbricated 
above ; smooth below ; aperture of a round polygonal form ; 
umbilicus large, penetrating to the apex of the shell. — Obs. 
This genus of fossils very nearly resembles Delphinula. The 
main difference appears to be that the whorls do not increase so 
rapidly in size in the former as in the latter. Fossil, in the Car- 
boniferous Limestone. Fig. 350. 

EXOGYRA. Sow. A genus of fossil bivalves, resembling Chama 
in shape and Ostrsea in structure, having but one muscular 
impression in each valve. Fig. 183. 

EXSERTED. Standing out, protruding. 

EXTERNAL. An external shell is one which contains the animal, 
and is not covered by the mantle. 

FASCIATED. (fascia, a band.) Banded or striped. Ex. Carocolla 
marginata, fig. 277. 

FASCICULATED, (from fasciculam) A little bunch of hairs or 

l 2 



148 FISTULANA. 

bristles against each end of each valve, characterizes some 
species of the genus Chiton, which are termed fasciculated species. 
FASCIOLARIA. Lam. Fam. Canalifera, Lam. Siphonosto- 
mata, Bl.— Descr. Elongated, fusiform, ventricose ; spire conical, 
consisting of few rounded or angulated whorls ; aperture wide, 
terminating in a long straight open canal : columella lip with 
several oblique folds, the lower of which is larger than the rest ; 
operculum horny, pyriform. — Obs. This genus is known from 
Fusus by the folds on the columella ; from Turbinella, by their 
obliquity and the last being larger than the rest. Fig. 386, F. 
Trapezium. East and West Indies and Australia. 
FAUNUS. Montf. Melanopsis, Auct. 
FERRUGINEOUS. Of an iron rust colour. 
FERUSSTNA. Grateloup. Strophostoma, Deshayes. 
FIBROUS. A shell is said to be of a fibrous structure when a 

fracture would present a series of perpendicular fibres, as Pinna. 
FICULA. Sw. A generic group of shells, consisting of those 
species of Pyrula, Auct. which have the true pear-shaped 
character. Fig. 390, P. Ficus. Sowerby confines the name 
Pyrula to these species. 
FIMBRIA. Megerle. Corbis, Lam. 
FIMBRIATED. Fringed ; as Murex fimbriatus, a delicate white 

species, with broad fringed varices. 
FISSURE {Fissura, a slit.) A slit or cut, a narrow perforation, as 

in Emarginula and Fissurella. 
FISSURELLA. Brug. (Fissura, a fissure) Fam. Calyptracia, 
Lam. Branchifera, Bl. — Descr . Patelliform, oval or oblong, 
radiated ; apex anterior, perforated. — Obs. The Fissurellse are 
known from Patellae by the perforation in the apex. Fig. 245. 
The catalogue published by the author in the Conchological Illus- 
trations, enumerates 68 species. 
FISTULANA. Lam. (Fistula, a pipe.) Fam. Tubicolae, Lam. 
Adesmacea, Bl. — Descr. A transversely elongated, equivalve, in- 
equilateral bivalve, enclosed by a septum within the widest, closed 
extremity of a straight calcareous tube. Fistulana is known 



FOSSIL SHELL. 149 

from Gastrochaena by the straightness of the tubes, and the oblong 
state of the valves. Fig. 54, Fistulana Clava. 

FLEXUOUS. Having windings or bendings. Ex, The Tellinse 
are known by the twist or flexuosity in the posterior ventral mar- 
gin of the shell. 

FLORILLUS. Montf. A genus of microscopic Foraminifera. 

FLU V1ATILE. (Fluviatilis.) Belonging to a river or running stream. 
Ex. Limneea fluviatilis. 

FLUVIATILE CONCHACEA. See Conchacea. 

FOLIATED, or FOLIACEOUS. (From folium, a leaf) When the 
edges of the successive layers of which a shell is composed are 
not compacted but placed apart from each other, projecting like 
tiles, the shell is said to be of a foliated structure. The common 
Oyster, fig. ISO, presents a familiar example. 

FORAMINIFERA. D'Orb. (Foramen, a hole or pit) An order 
established for minute many chambered internal shells, which 
have no open chamber beyond the last partition. Lamarck, 
D'Orbigny, and other writers have placed them among the 
Cephalopoda in their systems, but Du Jardin, on comparing the 
fossils with some recent species of the same class, arrived at the 
conclusion, now generally adopted, that they constitute a distinct 
class, much lower in degree of organization than even the Radiata. 
Not recognizing these microscopic bodies as shells, properly so 
called, but considering them sufficiently numerous and inter- 
esting to form a distinct branch of study, I do not think it desi- 
rable to describe the genera, or to present any arrangement of them 
in this work. 

FORNICATED. Arched or vaulted, as the exfoliations on the 
costse of Tridacna Elongata, fig. 157. 

FOSSIL SHELL. A shell is considered to be in a fossil state when, 
the soft parts having ceased to exist, it is deprived of all its animal 
juices, has lost all, or nearly all its natural colour, and is thus changed 
in its chemical composition, when little or nothing is left but a mere 
bone, which is embedded in a sedimentary deposit. In this state, it 
is fragile, prehensile to the tongue, and either destitute of colour or 
tinged with the diluted mineral matters which pervade the stratum 



150 FRESH-WATER SHELLS. 

in which it lies. In some cases, the mineral composition of the shell 
is so completely changed as no longer to present its proper structure, 
consistingof successive oblique layers of shelly matter; but is altered 
into a fibrous structure, composed of rhomboidal particles. An exam- 
ple of this will be found in the Belemnites, which if broken, shew 
the perpendicular fibres. In other cases, the matter which has 
entered and filled up the cavities of the shell has become silicified, 
or changed into flint, and the shell itself has been decomposed 
and fallen off, so as to leave nothing but an external or internal 
cast of its form, in flint. This is called a Conchyliomorphite by 
continental writers. Some of the most important of Geological 
data are obtained by a minute comparison of fossil shells, found 
in various beds, with recent ones presenting the nearest resem- 
blance to them. Some species of fossil shells are considered as 
identical with recent species. And many Geologists seek to fix 
the chronology of the different strata by the number of species 
which they inclose bearing a resemblance to the recent species. 
Indeed, all who would study Geology with success, will find it 
indispensably necessary to obtain a thorough knowledge of 
Conchology. 

FRAGELLA. Sw. A sub-genus of Monodonta, corresponding 
with the genus Clanculus, Montf. consisting of M. Pharaonis 
(fig. 361), and similar species. Sw. p. 352. 

FRAGILE. (Fragilis.) Tender, easily broken. 

FREE SHELL. One that is not attached. 

FREE VALVE. In attached bivalve shells, one only is fixed ; 
the other is then free, as far as to the action of opening and 
shutting. 

FRESH-WATER SHELLS, (sometimes described as aquatic) are 
those which either inhabit rivers, running pools and ditches, in 
which case they are fluviatile ; or wells and ponds of standing 
water, &c. Fresh-water shells are either thin and horny in their 
texture, as the Limneana of Lamarck ; or are covered with a 
compact, smooth, horny epidermis. They are generally simple 
in form, subject to corrosion where the epidermis is wounded or 
broken, and are circumscribed with regard to the classes and 



GALEOMMA. 151 

genera to which they belong. The family of Nayades includes 
nearly all the fresh-water bivalves ; and the Melaniana and Lim- 
neana are the principal among univalves. 

FRONDICULARIA. Defr. A genus of microscopic Foraminifera. 

FRONT. The surface of a shell on which the aperture appears. 

FULCRUM. That part of a shell on which any other part rests 
or turns. The term is applied more particularly to the tumid 
part in the hinge of bivalve shells on which the ligament is 
fixed. 

FULGUR. Montf. Pyrula perversa, Auct. and such other 
species as have an angulated spire. Fig. 388. 

FUSIFORM. (Fusus, a spindle.) Shaped like a spindle, swelling 
in the centre and tapering at the extremities. Ex, Fusus, fig. 387. 

FUSUS. Brug. (A spindle.) Fam. Canalifera, Lam. Siphono- 
stomata, Bl. — Bescr. Fusiform, turrited, with many rounded 
whorls ; aperture generally oval, terminating in a long straight 
canal ; operculum horny, pyriform. — Obs. The Fusi are subject 
to considerable variations in form. The recent species are 
numerous and do not appear to be confined to any climate. The 
fossil species are also numerous, chiefly abounding in the tertiary 
formations. The recent species are mostly tropical. Fig. 387, 
F. Colus. 

GALATHiEA. Brug. Potamophila, Sow. Megadesma, Bowd. 

GALEA. Klein. Purpura, Auct. 

GALEOLARIA. Lam. (From Galea, a helmet or crest.) A genus 
composed of species of Serpula, Auct. Distinguished as being 
fixed by the side of the shell, and having the anterior extremity 
erect, the aperture terminating in a tongue- shaped projection. — 
Obs, This genus is said by Lamarck to resemble Vermilia in 
other respects, but to differ in having the anterior part raised. 
Fig. 6, G. decumbens. Africa and Australia. 

GALEOMMA. Turt. Fam. Pholadaria, Lam.— Descr. Thin, 
oval, equivalve, equilateral, with the ventral margin gaping ; 
hinge with one cardinal tooth in each valve; muscular impressions 
two, approximate ; palleal impression interrupted, not sinuated ; 
ligament small, partly internal, partly external, fixed on a promi- 



152 GEOMITRA. 

nent fulcrum. — Obs. The wide hiatus in the ventral margins of 
this equilateral shell prevents the possibility of confounding 
it with any other. Four or five recent species are known, one of 
which is found on the coast of Sicily, and also in the British 
Channel. G. Turtoni, fig. 58. 

GALERICULUS. (Galericulum, a little cap or bonnet.) Velutina, 
Auct. fig. 337. 

GALERUS. Humph. Calyptr^ea, Lam. 

GAPING. (Hians.) Bivalve shells are said to gape when the 
margins do not meet all round. Ex. Gastrochsena, fig. 52. 

GABI. Schum. Psammobia, Lam. 

GASTEROPODA. Lam. (Taar^p, gaster, belly ; Trove, koSoq, 
pus, podos, a foot.) The second order of the class Mollusca, Lam. 
containing those molluscous animals whose organs of locomotion 
are ventral. Most of the shells belonging to this order are 
patelliform, placed upon the back of the animals, which rest or 
crawl upon the belly. This order is divided into Pneumonobran- 
chiata, that is, those which breath air, or land molluscs ; and Hy- 
drobranchiata, or those which breath water, marine or fresh-water 
molluscs. Fig. 227 to 263. 

GASTRANEA. Schum.? Coubula, Auct. 

GASTROCHiENA. Speng. (Taarrjp, gaster, belly ; x alvti) > ckcrino, 
gape.) Fam. Pholadaria, Lam. Pyloridea, Bl. — Bescr. Equi- 
valve, regular, inequilateral, with a wide, oblique, ventral hiatus, 
enclosed in a curved pyriform tube. Differing from Galeomma in 
being a free, oblique shell ; from Fistulana, in the oval shape of 
the valves, and the curve of the tube; from Aspergillum and Clava- 
gella, in both valves being free. — Obs. The Gastrochsenoe are 
found in the hollows of massive shells or other marine substances. 
Fig. 62, G. Modiolina. 

GASTROPLAX. Bl. Umbrella, Lam. De Blainville described 
this genus from a specimen in which the shell had been, proba- 
bly by accident, placed upon the under part of the animal, and 
not discovering his error until afterwards, gave it the above name. 

GEOMITRA. Sw. A sub-genus of Geotrochus, Sw. founded on 
a trochiform species of Helix, with coronated nodules on the 






GLAUCONOME. 153 

whorls. Helix bicarinata, Sow. Zool. Journ. 1, pi. 3, fig. 7. 
Sw. page 166 and 332. 

GEOPHONUS. Montf. Conch. Syst. t. 1, p. 19. A genus of 
microscopic Foraminifera. 

GEOTROCHUS. Sw. Helix pileus, Auct. (fig. 278,) and other 
trochiform species. Divided into the sub-genera Pithohelix, 
Geotrochus, Hemitrochus, Gonidormus, and Geomitra. Sw. p. 
165 and 166, described at page 331. 

GEOVULA. Sw. A sub-genus of Melampus (Auricula), con- 
sisting of oval species, resembling Auricula Midse, fig. 297. 

GERVILLIA. Defr. Fam. Margaritacea, Bl. Malleacea, Lam. 
—Descr. Equivalve, oblong, oblique ; hinge long, straight, 
having small, irregular, transverse ligamentary pits. — Obs. This 
genus of fossil shells, found at various geological periods, from 
the Lias to the Baculite limestone in Normandy, is now extinct. 
In general form it resembles Avicula, but in the hinge it ap- 
proaches Perna. Fig. 169, G. Avicularis. 

GIBERULA. Sw. A genus separated from Marginella, Auct. 
and thus described, " sub-oval ; spire slightly prominent ; top 
of the outer lip dilated and gibbous ; base of the inner lip 
with plaits ; inner lip broad, spreading. G. Zonata. Enc. Meth. 
374, f. 6." 

GIBBOSE or GIBBOUS. (Gibbosus.) Bunched out, embossed, 
having a lump or swelling of any kind. Ex. Bulinus Lyone- 
tianus, (fig. 284.) named Gibbus by De Montfort. Ovulum 
gibbosum. 

GIBBUS. Montf. Bulinus Lyonetianus, Lam. Pupa, Bl. fig. 
284. 

GIOENIA. A name given in the Encyclopedic Methodique, to the 
plates of the stomach of Bulla Lignaria. 

GLABELLA. Sw. Marginella Glabella (fig. 437), Goodallii, 
Auct. and similar species. 

GLANDINA. Schum. Polyphemus, Montf. 

GLANDIOLUS. Montf. A genus of microscopic Foraminifera. 

GLAUCONOME. Gray. Fam. Solenacea, Lam.— .Descr. Oblong 



154 GNATHODON. 

or oval, transverse, slightly ventricose, equi valve, inequilateral ; 
margins close, rounded anteriorly, somewhat acuminated poste- 
riorly ; hinge teeth, three in each valve, of which the central 
in one, and the posterior in the other, are bifid ; muscular im- 
pressions anterior, elongated, marginal ; posterior sub -quadrate ; 
palleal impression, having a long sinus ; ligament oblong, ex- 
ternal ; epidermis thin, horny, green, folded over the margins. 
— Obs. This shell, of which only one species is known, inhabits 
some of the rivers in China. C. Chinensis, fig. 64. 

GLOBIGENERA. D'Orb. A genus of microscopic Foraminifera. 

GLOBOSE. (Globosus.) Rounded like a globe or ball, as the 
species of Helix, represented in fig. 268. 

GLOBULARIA. Sw. A sub-genus of Natica, consisting of 
globose species. (Sw. p. 345.) Ex. N. Lineata, fig. 328. 

GLOBULUS. Sow. Min. Con. Ampullaria, Auct. 

GLYCIMERIS. Lam. Farn. Solenacea, Lam. Pyloridea, Bl. — 
Descr. Equivalve, transverse, oblong, thick, compressed, gaping 
at both extremities ; hinge callous, without teeth ; ligament 
large, external, prominent; epidermis thick, black, horny, folded 
over the margins ; muscular impressions two, distant, running 
into the irregular palleal impression which unites them. — Obs. 
But few species of this singular genus are known ; Lamarck 
describes two species from the Northern Seas. Blainville is of 
opinion that they belong to the family of the Nayades. Fig. 
67, G. Siliqua. 

GNATHODON. Gray. (YvclQoq, gnathos, jaw-bone ; oSog, oSovtoq 
odontos, tooth.) Fam. Mactracea, Lam. — Descr- Ovate, poste 
riorly angulated, equivalve, thick, ventricose, inequilateral 
covered with a greenish brown epidermis ; umbo distant, pro 
minent ; hinge having in one valve a sharp, angular, notched, 
cardinal tooth, and two lateral teeth, the posterior of which is 
elongated, and the anterior angulated, tortuous, shaped like 
a jaw-bone ; in the other valve, two cardinal and two lateral 
teeth, the anterior of which is wedge-shaped ; ligament internal, 
cuneiform, placed in a deep cardinal pit, proceeding from 



GRYPH^EA. 155 

the umbones ; muscular impressions two ; palleal impression 
having a slight sinus. — Obs. Only one species is known, G. 
cuneatus, fig. 83, from New Orleans. It is known from all 
other shells by the character of the hinge. 

GONIATITES. De Haan. A genus composed of species of 
Ammonites, Auct. in which the last whorl covers the spire and 
the sinuations of the septa are angulated. Fig. 480, G. striatus. 

GONIDOMUS. Sw. A sub-genus of Geotrochus, Sw. Pupa 
pagodus, Auct. Sw. p. 332. 

GONIOSTOMA. Sw. A sub-genus of Bulimus, thus described, 
"spire elongated, of few whorls ; aperture contracted at each 
end ; lips margined ; the pillar curving inwards ; the base 
slightly notched. G. erubescens, Sw. Zool. Journ. i. pi. 5, f. 2." 
Sw.p. 335. 

GONIOSTOMATJE. Bl. A family belonging to the order Asi- 
phonibranchiata, Bl. containing the genera Solarium and 
Trochus. 

GONOSPIRA. Sw. A sub-genus of Pupa, thus described, " spire 
perfectly cylindrical, of equal thickness, the tip obtuse, with the 
whorls large ; aperture oval ; lips thickened ; pillar with or 
without a plait. G. polanga, Desk. Lesson, Voy. pi. 8, f. 8." 
Sw. p. 333. 

GRANULATED. (Granum, a grain.) Covered with minute grains, 
rough. The granulated lip of Oniscia, (fig. 409) will serve as 
an example. 

GRATELOUPIA. Moulins. Fam. Nymphacea, Lam.— Dewcr. 
Equivalve, inequilateral, sub -cuneiform, rounded anteriorly, sub- 
rostrated posteriorly ; hinge with three cardinal teeth, a series 
of five or six irregular, small, diverging teeth behind the um- 
bones, and one lateral anterior tooth in each valve ; ligament 
external ; muscular impressions two ; palleal impression sinuated 
posteriorly. — Obs. This genus (Donax irregularis, Bast.) is only 
known in a fossil state. Fig. 102, G. Moulinsii. 

GRYPHiEA. Lam. (Prom Gryps, a griffin.) Fam. Ostracea, 
Lam. — Descr. Inequivalve, free ; lower valve large, concave ; 



156 HAMITES. 

with the umho prominent, incurved ; upper valve small, flat, 
opercular ; hinge toothless, with a curved, depressed area ; one 
muscular impression. — Obs. These shells, which approach the 
Oysters, are of a more regular form, and are remarkable for the 
curved, produced beak of the lower valve. They are only known 
in a fossil state, belonging to the more ancient strata. Fig. 182, 
G. incurva. The recent species mentioned by Lamarck is not a 
true Gryphsea. 

GYMNOLEPAS. A generic name used by De Blainville to include 
Otion and Cineras, Leach. 

GYMNOSOMATA. Bl. The second family of the order Aporo- 
branchiata, in the system of De Blainville. The animals belonging 
to this family are destitute of shells. 

GYPIDEA. Dalman. A genus of Brachiopoda, thus described, 
" Larger valve with the umbo rostrated, remote from the hinge ; 
with the canal large, deltoid ; bilocular within." Pentamerus, 
Sow. Fig. 210. 211, G. Conchidium, copied from Dalman. 

GYROGONA . Lam. A genus of microscopic Foraminifera. 

GYROIDINA. D'Orb. A genus of microscopic Foraminifera. 

HALIOTlDiE. Sw. A sub-genus of Calyptrsea. Calyptr^ea 
dilatata. Sowerby's Genera of Shells, fig. 9. 

HALIOTIS. Auct. (a\c, ah, sea ; ovg, wrog, otos, ear.) Fam. 
Macrostomata, Lam. Otides, Bl. — Descr. Auriform, broad, de- 
pressed, pearly within, rough, costated, tuberculated without; 
spire short, flat, consisting of one or two whorls ; aperture wide ; 
ovate ; columella laminar, flat, obilque ; a spiral series of perfo- 
rations running along the dorsal margin. — Obs. The splendid 
shells belonging to this genus are remarkable for the pearly 
iridescence of the inner surface, and the row of holes following 
the course of the spire. The soft parts are eaten in Guernsey 
and Jersey, and reckoned delicious. They belong to temperate 
and tropical climates. Fig. 338, H. rubra. 339, Padollus, Montf. 

HALIOTOID. (Haliotis and eihoq, eidos, form.) Ear-shaped. 

HAMIFORM. (Hamus, a hook.) Curved at the extremity. 

HAMITES. Parkinson. (Hamus, a hook.) Fam. Ammonacea, 



HELCION. 157 

Lam. — Descr. Elongated, cylindrical, chambered, recurved at 
the smaller extremity, annulated ; septa lobed and sinuated. — 
Obs. This remarkable fossil from the Baculite limestone in 
Normandy, differs from Baculites in being curved at one extremity, 
a circumstance from which its name is derived. Some small 
species are found in Chalk-Marie, Folkstone. Fig. 484*. H. 
cylindricus. 

HARPA. Brug. (Harpa, a harp.) Fam. Purpurifera, Lam. 
Entomostomata, Bl. — Descr. Oval, ventricose, longitudinally 
and regularly costated ; spire short, with rounded, dome-like 
whorls ; aperture wide, emarginated ; outer lip thickened, re- 
flected, composing the last costa or rib ; inner lip polished, spread 
over part of the body whorl, terminating in a point. — Obs. 
This beautiful genus of shells is so clearly defined by the regular, 
longitudinal ribs that adorn the external surface, suggesting the 
idea of a stringed instrument, that there is no danger of con- 
founding it with any other. H. multicostata, (Buccinum cos- 
tatum, Linn.) and H. ventricosa, are among the most elegant of 
the testaceous productions of the sea both in form and colouring ; 
the former is rare. The recent species are not numerous, they 
inhabit the Indian Ocean. A fossil species occurs at Grignon, 
near Paris. Fig. 419, H. ventricosa. 

HARPAX. Parkinson. Part of Plicatula, Auct. 

HARPULA. Sw. A group of shells separated from Voluta, 
Auct. thus described, " shell generally tuberculated or longitu- 
dinally ribbed ; apex of the spire papillary, smooth, and in general 
distorted ; pillar with numerous distinct plaits ; the upper, 
small and slender, the lower, thickest and shortest." — Type, H. 
Vexillum. (Voluta, Auct.) 

HAUSTATOR. Montf. A genus proposed to include those species 
of Turritella, Auct. which have angulated whorls. 

HAUSTELLARIA. Sw. A sub-genus of Murex, consisting of 
species with long canal and no spines. Murex Haustellum, fig. 396. 

HAUSTRUM. Humph. Purpura, Lamarck. 

HELCION. Montfort. A genus composed of species of Patella, 



158 HELICOLIMAX. 

which have the apex distinctly and prominently bent forwards. 
Ex. P. pellucida, fig. 230. 

HELENIS. Montf. A genus of microscopic Foraminifera. 

HELICELLA. Fer. One of the sub-genera into which De 
Ferussac has divided the genus Helix, consisting of depressed 
species with large umbilicus, such as Helix Algira, fig. 279. 
Gonites Montf. 

HELICIFORM. Shaped like shells of the genus Helix. 

HELICIGONA. One of De Ferussac's sub-genera of the genus 
Helix, consisting of angulated species, such as Carocolla 
Lamarckii, fig. 277. 

HELICINA. Lam. Fam. Colimacea, Lam. Ellipsostomata, Bl. 
— Descr. Globose, compressed, or angulated, generally light and 
thin ; aperture trigonal or semilunar ; outer lip thickened and 
generally more or less reflected ; inner lip spread over the body 
whorl, frequently callous near the columella, which is short, and 
terminates in a notch, angle, or slight callosity.— Obs. This genus 
of land shells, distinguished from the genus Helix, by having an 
operculum and a thickened columellar lip, differs also from 
Cyclostoma in having the aperture semicircular or angular, the 
peritreme discontinuous and the operculum concentric. These 
shells are generally small in size, and simple in form. Lamarck 
describes only three or four species. Mr. Gray described some 
others in the Zoological Journal, and in a work shortly to be 
published by the author, a monograph of the genus will contain 
descriptions and figures of at least 60 distinct species ; some of 
which have been lately brought to this country by Mr. Cuming 
from the Philippine Islands. They mostly belong to tropical 
climates. 

HELICITES. Bl. Part of the genus Nummtjlites, Lam. Rota- 
lites and Egeon, Montf. 

HELICOGENA. Fer. A sub-genus of Helix, consisting of species, 
which, like the common garden snail, fig. 268, are globose and 
simple in form. 

HELICOLIMAX. Fer. Vitrina, Drap. H. Pellucida, fig. 263. 






HELIX. 159 

HELICOPIIANTA. Fer. A sub-genus of Helix, consisting of ear- 
shaped species with large open apertures. 

HELICOSTYLA. Fer. A sub-genus of Helix, consisting of species 
with numerous whorls, as H. Epistylium, fig. 281. 

HELISOMA. Sw. A sub-genus of Planorbis. Sw. p. 337. 

HELIX. Auct. Fam. Colimacea, Lam. — Descr. Orbicular, light, 
generally globular; spire short, last whorl ventricose, aperture 
oblique, peritreme reflected, interrupted by the most prominent 
part of the body whorl; columella confluent with the outer lip, 
and contiguous to the axis of the shell. No operculum ; a thin 
epidermis. — Obs. The land shells composing this genus are 
found in all parts of the world; the common snail, H. Aspersa, 
is well known as a destructive animal in our gardens. The 
genera Helix, Achatina, Bulinus, Clausilia, Anostoma, &c, have 
been united under one generic name by De Ferussac, and again 
divided under the following sub- generic names, each of which we 
shall illustrate by a figure. Genus Helix : Sub-genus 1 , Helico- 
phanta, consisting of species with large apertures, like Vitrina ; 
Helix brevipes. S. gen 2, Cochlohydra, Succinea Amphibia, 
Drap. S. gen. 3, Helicogena, consisting of the common species 
with the last whorl large; Helix Hsemastoma, II. Contusa, (Strep- 
taxis, Gray,) H. Aspersa. S. gen. 4, Helicodonta, consisting of 
species with teeth or folds on the columella; Polydonta, Montf. 
Anostoma, Helix Nux-denticulata. S. gen. 5, Helicigona, Caro- 
colla, Geotrochus. S. gen. 6, Helicella, consisting of depressed 
species with a large umbilicus ; H. Citrina (Naninia, Gray.) 
S. gen. 7, Helicostyla, consisting of species with a simple aper- 
ture, like the Helicogense, but with the whorls increasing very 
gradually; H. epistylium. S. gen. 8, Cochlostyla, Bulinus. S. 
gen. 9, Cochlitoma, Achatina. S. gen. 10, Cochlicopa, Poly- 
phemus Glans. S. gen. 11, CocJilicella, Bulinus decollatus. »S. 
gen. 12, Cochlogena, Azeca tridens. S. gen. 13, Cochlodonta, 
Pupa Uva. S. gen. 14, Cochlodina, Clausilia macascarensis, 
Balea fragilis. The last three sub-genera are included in the 
genus Odostomia of Fleming. We give an example of each of 



160 HEMITOMA. 

these sub-divisions, for the sake of presenting the reader with 
the principal variations to which the genus is subject. The 
established genera will be characterized in their places. Fig. 254 
to 281. 

HELIXARION. Fer. Vitrina, Drap. Differing from Helico- 
limax in the structure of the animal. Fig. 262. 

HEMICARDIUM. Cuv. (r/juiaue, hemisus, half, Kapc)ta, cardia, 
heart.) Cardium Hemicardium, fig. 123**, and several similar 
species. 

HEMICYCLA. Sw. A sub-genus of Helix. 

HEMICYCLONOSTA— see Cardilia. 

HEMICYCLOSTOMATA. Bl. The fourth family of Asiphonibran- 
chiata, Bl. described as " more or less globular, thick, flattened 
on the under side; spire very short; aperture large, semilunar, 
entire; its outer edge hollowed; its inner or columellar edge 
straight, sharp and septiform.' , This family answers to the 
genus Nerita of Linnaeus, and to the family Neritacea of 
Lamarck. It contains the genera Natica, Nerita, Neritina, and 
Navicella. 

IIEMIMACTRA. Sw. A sub-genus of Mactra, thus described : 
" General form of Mactra ; but the cardinal teeth entirely want- 
ing; cartilage internal, central, in a large triangular cavity; 
lateral teeth 2, distinct, lateral, striated: connected to the Gly- 
cimeri. H. gigantea, Lam. v. 472. No. 1. grandis, Su>. Sp. 
Nov." Sw. p. 369. 

HEMIMITRA. Sw. A sub-genus of Paludomus, Sw. (Melanianse.) 

HEMIODON. Sw. A sub-genus of Anodon, described as having 
" Tubercles or undulations on the hinge margin. H. undulatus, 
purpurascens and areolata." 

HEMISINUS. Sw. A sub-genus of Melania, thus described : 
" General shape of Melania ; but the base of the aperture is con- 
tracted and emarginate ; outer lip crenated. H. lineolata, Griff. 
Cuv. xii.pl. 13. fig. 4." 

HEMITOMA. Sw. A sub-genus of Emarginula, thus described : 
" Patelliform; the fissure not cut through the shell, but merely 



HIATULA. 161 

forming an internal groove. H. tricostata, Sw. Sow. Gen. 
fig. 6." 

HEMITROCHUS. Sw. A sub-genus of Geotrochus, Sw. H. 
haemastoma. Sw. p. 331. 

HEPTALASMIS. Leach. ('ETrra, hepta, seven ; ekacr/ia, elasma, 
plate.) A small shell resembling Pentelasmis, from which it 
differs in the number of valves, being composed of seven valves 
according to Leach, and of eight according to Gray, who counts 
the dorsal valve, which is jointed, as two, and names his genus 
Octolasmis. Fig. 41, H. Warwickii. 

HERCOLES. Montf. A microscope shell, appearing from De 
Montfort's figure to resemble Trochus Imperialis in shape. 

HERION. Montf. Lenticulina, Bl. Microscopic. 

HERMAPHRODITA. Bl. The third sub-class of Paracephalo- 
phora, Bl. divided into, Sect. 1, symmetrical, containing the 
orders Cirrobranchiata and Cervicobranchiata ; Sect. 2, non-sym- 
metrical, order, Scutibranchiata. 

HERMES. Montf. A genus composed of Conus Nussatella, 
Auct. and other elongated, cylindrical, striated species. Fig. 
460. 

HETEROBRANCHIATA. Bl. The fourth order of the class Ace- 
phalophora, Bl. containing no testaceous mollusca. 

HETEROPODA. Lam. The fifth order of the class Mollusca, 
Lam. This order contains but one genus of shells, viz. Carinaria, 
fig. 488. 

HETEROSTEGINA. D'Orb. A genus of microscopic Foramini- 
fera. 

HIATELLA. Daud. Fam. Lithophagidse, Lam. A genus com- 
posed of species of Saxicava, Auct. which have sharp, angulated, 
posterior ridges, a circumstance which occurs to many species 
in a young state, which afterwards become rounded off. Fig. 95, 
Hiatella biaperta. 

HIATULA. Sw. A genus proposed to include those species of 
Oliva, Auct. which have widened apertures. Ex. 0. Subulata, 
fig. 458. 

M 



162 HIPPOPODIUM. 

HIBOLITHES. Montf. A genus composed of species of Belem- 
nites, Auct. which are swelled towards the apex, and contracted 
near the centre. B. Hastatus, Auct. fig. 468. 

HIMANTOPODA. Schum. Malleus, Auct. 

HINGE. The edge of the bivalve shells near the umbones, in- 
cluding the teeth and ligament. 

HINNITES. Defr. A generic name proposed for Pecten Pusio, 
Auct. remarkable for the irregularity of the outer surface, which 
would almost lead to the belief of its being an attached shell. 
Fig. 173, H. Pusio. 

HIPPAGUS. Lea. {Horse boat.) A minute fossil shell, re- 
sembling Isocardia in form, but destitute of hinge teeth. H. Iso- 
cardioides, fig. 128. 

HIPPOCHRENES. Montf. Species of Rostellaria, Auct. with 
the outer lip spread. Fig. 403. R. Columbaria. 

HIPPONYX. (I-mrog, hippos, horse ; owl;, onyx, nail or hoof.) 
Fam. Rudistes, Lam. — Bescr. Inequivalve, sub-equilateral, rather 
irregular, destitute of ligament and hinge teeth ; lower valve 
attached, flat, sub -orbicular, with a muscular impression, com- 
posed of two lunulate portions, meeting at one extremity, and 
presenting the form of a horse- shoe ; upper valve conical, with 
the apex inclined backwards, and the muscular impression mar- 
ginal. — Obs. The earlier naturalists having only met with the 
upper valve of these shells, placed them among the patelliform 
univalves ; to some of which, particularly Pileopsis, they bear a 
very strong resemblance. The species of Hipponyx are nume- 
rous, and till lately only known in a fossil state. The recent 
species belong to tropical climates : the fossil species are found in 
the tertiary beds. Fig. 199, H. Cornucopia. 

HIPPOPODIUM. Conybeare. Fam. Cardiacea, Lam. — Bescr. 
Equivalve, obliquely transverse, heavy, deep, inequilateral, um- 
bones incurved ; ventral margin sinuated, so as to give a bilobed 
appearance to the shell ; hinge incrassated, with one rugged 
oblique tooth. — Obs. These fossils are found in the upper beds of 
Lias. Fig. 129, H. Ponderosum. 






HYALvEA. 163 

HIPPOPUS. Lam. ('Ittttoc, hippus ; ttovg, pons, foot.) Fam. 
Tridacnacea, Lam. — Descr. Equivalve, inequilateral, regular, sub- 
quadrate ; lunule closed, flat, with crenulated edges ; ventral 
margin deeply undulated ; external surface fluted, with radiating 
ribs, which are transversely fringed with rows of tubular spines ; 
hinge margin thick, with two long, compressed posterior lateral 
teeth in one valve, three in the other ; ligament marginal, exter- 
nal. — Obs. The shell thus described is rightly separated from 
Tridacna, on account of the anterior dorsal margins being closed ; 
whereas in Tridacna there is a wide hiatus. Only one species of 
this genus is known, which receives its name from its resemblance 
in form to a horse's foot, when held with the flat anterior dorsal 
margin downwards. Few shells are found to concentrate so many 
beauties as the Hippopus Maculatus, commonly called the Bear's - 
paw- clam ; the delicate whiteness of the interior, the undulating 
edge, the radiated fluted columns, adorned at intervals by crisped 
fringes, and the richness of the variegated colouring, are such as 
to secure the admiration of the most superficial observer. From 
the Indian Archipelago. Fig. 156, H. Maculatus. 

HIPPURITES. Montf. Fam. Orthocerata, Lam. Rudistes, Bl. 
— Descr. Tubular, rude, irregular, attached ; lower valve cylindri- 
cal, more or less lengthened, apparently divided into sections by 
septa (considered by some authors as merely projecting layers of 
growth) having one or two lateral tubes within; upper valve 
round, flat, fixed on the aperture of the tubular valve like an oper- 
culum. — Obs. This genus is known only in a fossil state, and but 
very imperfectly. Lamarck places it among his chambered Cepha- 
lopoda, &c. De Blainville, considering it a true Bivalve, enume- 
rates it among his Rudistes. Cretaceous group. Fig. 198, H. 
Cornucopia. 

HORTOLUS. Montf. Spirolina, Lam. Microscopic. 

HYALiEA. Auct. (Hyalus, glass.) Fam. Pteropoda, Lam. 
Thecosomata, Bl. — Descr. Globose, glassy, transparent, with a 
triangular opening at the upper part where the dorsal portion 
advances beyond the ventral ; ventral portion vaulted ; dorsal 

m 2 



164 JANTHINA. 

more flat ; lower extremity tridentate. — Obs. The singular struc- 
tures composing this genus were formerly taken for bivalves, and 
named Anomia Tricuspidata, &c. They are now known to belong 
to the class of molluscous animals, called Pteropoda, from the 
wing-shaped organs of locomotion. A species of Hyalsea occurs 
in Sicily in a fossil state. Recent species are found in the Medi- 
terranean, Atlantic, and Indian Oceans. Fig. 226, H. Tridentata. 

HYALINA, Studer. Vitrina, Drap. 

HYALINE. (Hyalus, glass.) Glassy, thin, transparent — Zfo. 
Carinaria Mediterranea, fig. 488. 

HYDROBRANCHIATA. Bl. The first section of the order Gas- 
teropoda, Lam. containing Molluscs which breathe water only ; 
divided into the families Tritoniana, Phyllidiana, Semi-phyllidiana, 
Calyptracea, Bullseana, and Aplysiana. 

HYGROMANES. Fer. A sub-division of Helix, containing H. 
limbata, Auct. &c. Gray's Turton, p. 143. 

HYRIA. Lam. A genus composed of species of Nayades, dis- 
tinguished by their alated dorsal margins, and lamellated lateral 
teeth. South America. Hyria corrugata, fig. 143, Hyria Syr- 
matophora, fig. 144. 

HYRIDELLA. Sw. A genus of " Hyrianse," Sw. described as 
differing from Hyria, Auct. in having a cardinal as well as a 
lateral tooth in each valve. Sw. p. 380. 

HISTRIX. Humph. Ricinula, Auct. 

JANERA. Schum. A genus composed of species of Pecten, 
Auct. having oblique plicae or calli on each side of the ligamen- 
tary pit. Ex. P. plica, fig. 172. Decadopecten, Ruppell, 

JANTHINA. Auct. {Janthum, a violet.) Fam. Neritacea, Lam. 
Oxystomata, Bl. — Descr. Sub-globose, thin, fragile ; spire short, 
consisting of few whorls; aperture angulated, at the anterior 
junction of the inner and outer lips ; columella tortuous, con- 
tiguous to the axis ; outer lip thin, sinuated in the centre. — Obs. 
The shells composing this genus are celebrated for their beautiful 
purple colour. The animal possesses a small vesicular process, 
which keeps it floating on the surface of the water ; it exudes a 
purple secretion when irritated. It is occasionally floated on to 






INDENTED. 165 

the shores of most temperate and tropical countries. Fig. 333, 
J. Fragilis. 

JATARONUS. Adanson. Chama, Auct. 

IBERUS. Montf. Carocolla, Lam. 

IBLA. Leach. Fam. Pedunculated Cirripedes, Lam. — Descr. 
Four valves, posterior pair elongated, anterior pair short, trian- 
gular ; pedicle cylindrical, contracted at the base, hairy. — 
Obs. I. Cuveriana (fig. 40) is brought from Kangaroo Island. 

ICTHYOSARCOLITES. Desmarest. Fam. Ammonacea, Lam.— 
Descr. Chambered, slightly arcuate, laterally compressed; septa 
simple, leaving triangular articulations imbricated like the thick 
muscles of a fish. 

JESITES. Montf. A minute fossil resembling Galeolaria. 

ILOTES. Montf. Orbiculina, Bl. A genus of microscopic 
Foraminifera. 

IMBRICARIA. Schum. Conohelix, Sw. 

IMBRICATED. {Imbrex, a tile.) A shell is said to be imbricated 
when the superficial laminae are arranged over each other in the 
manner of tiles. 

IMPERATOR. Montf. A genus composed of species of the genus 
Trochus, Auct. with whorls angulated and stellated^ having an 
umbilicus. Ex. T. Imperialis. Some of the shells named Impe- 
rator in the British Museum belong to the genus Calcar, Montf. 
having no umbilicus. 

IMPRESSION. See Muscular Impression. 

INCRASSATED. (Crassus, thick.) Thickened, as the hinge of 
Glycimeris, fig. 67- 

INCURVED. Turned inwards or bent forwards. Applied to sym- 
metrical shells, when the point of the apex turns towards the 
anterior extremity, as in Patella. The apex of a shell is said to 
be incurved when it is bent inwards, but not sufficiently so to be 
described as spiral. Ex. Ammonoceras, Lam. fig. 477. 

INDENTED. (In, in ; dens, a tooth.) Exactly the reverse of 
Dentated; meaning a series of small cavities, such as might be 
produced by the entrance of teeth. The cast of a dentated surface 
would be indented. 



166 INTERNAL CAST. 

INEQUILATERAL, (JEquus, equal; latus, a side.) A term ap- 
plied to a bivalve shell when its extent on one side of the umbones 
is greater than that on the other. When the sides are nearly 
equal, the term sub-equilateral is used. 

INEQUIVALVE. (in ; cequus, equal ; valva, valve.) The two 
principal valves differing from each other in diameter or con- 
vexity. 

INFERIOR VALVE is that which is attached to sub-marine bodies. 
Only applied to attached bivalves. 

INFEROBRANCHIATA. Bl. The fourth family of the second 
section of Paracephalophora Monoica, Bl. containing no tes- 
taceous mollusca. 

INFLATED. Swelled, as Bulla, fig. 250, 252. This term can 
only be applied to rotund shells of a light, thin texture. In other 
cases we should use the word Ventricose. 

INFLECTED. Turned inwards. This term is applied to the outer 
lip of a spiral shell when it turns towards the body whorl. This 
is the case in Cypreea, fig. 446. See Reflected. 

INFUNDIBULUM. Montf. (A funnel.) A genus formed of those 
species of Calyptr^a, Lam. which, having a spiral septum, so 
nearly resemble Trochus that some authors have placed them in 
that genus. One species named Patella Trochiformis. Recent 
from South America, fossil from the tertiary beds. Fig. 237, 238, 
Calyptrsea (Infundibulum) Pileus. 

INNER LIP. That edge of the aperture of an univalve shell which 
is near to the imaginary axis, as distinguished from the outer lip, 
or that which is on the opposite side. 

INOCERAMUS. Sow. Fam. Malleacea, Lam. Margaritacea, Bl. 
— Descr. Thick, inequivalve, sub-equilateral, triangular, deep, 
with the umbones incurved ; hinge formed of a series of trans- 
verse grooves. — Obs. The larger valves of these fossil shells re- 
semble the larger valve of Gryphsea ; but the hinge is quite 
distinct. The species described in Mineral Conchology are found 
in the blue marl, at Folkstone, and in the chalk. I. Lamarckii, 
(Catillus, Brong.) fig.167 . 

INTERNAL CAST. The mould of a fossil shell, composed of 



IRIDINA. 167 

matter which entered the shell in a soft state, and has subse- 
quently hardened, when, the shell dropping off, the hardened 
substance which filled it is left to represent its internal form. 

INTERNAL LIGAMENT. A term used by some conchological 
writers signifying that the ligament of a bivalve shell is placed 
within the closed part of the hinge, so as not to be seen when 
the valves are shut. But the substance, formerly called the in- 
ternal ligament, is now distinguished from the true ligament 
both in structure and use ; and is now more properly called the 
cartilage, so that when the ligament is said to be internal, it 
must be understood that the internal cartilage is unaccompanied 
by any ligament properly so called, and when a shell is described 
as having two ligaments, as in the case of Amphidesma, it means 
that the two substances are so far removed from each other in the 
hinge that they are no longer confounded together. 

INTERNAL SHELL is one which is enclosed in the soft parts of 
the animal, as a bone is enclosed in the flesh of a human body. 
The Limax, or common garden slug, which has a testaceous 
shield beneath its mantle, is an instance of this. 

10. Lea. A genus composed of several species of fresh-water 
shells which are considered as differing from Melaniae in having 
the anterior termination of the aperture produced into a point in 
some degree resembling the caudal canals of shells belonging to 
the family of Canalifera, which are marine. Io fusiformis and 
spinosus are described and figured in Lea's work on the genus 
Unio. 

JODAMIA. Defr. A genus resembling Birostrites, except that in 
Jodamia one valve overwraps the other, while in Birostrites the 
circumference of the valves is equal. 

IPHIGENIA. Gray. A sub-genus of Clausilia, C. biplicata, &c. 
Auct. Gray's Turton, p. 214. 

IRIDEA. Sw. A genus of " Hyrianoe," Sw. thus described : — 
" Oblong ovate ; bosses small, depressed, sulcated ; inner car- 
dinal tooth placed beneath the outer. I. granosa, Lam. En. 
Meth. 248. fig. 9." 

IRIDINA. Auct. A genus belonging to the Nayadcs, and re- 



168 LACUNA. 

sembling the Anodont^e, Auct. but its peculiar characteristic 
is that the hinge lamina is tuberculated or crenulaated in its 
whole length. Sowerby unites all the genera of the family into 
the genus Unio. Fig. 150, I. Elongata. 

IRREGULAR SHELLS, are those which, being attached to, or 
imbedded in other marine bodies, have no constant form, but are 
modified in shape according to the substances to which they are 
fixed, as the Chamacea, fig. 153 to 155. 

IRUS. Oken. Comprehending Pandora, Petricola, Saxicava, 
&c. 

ISOCARDIA. Lam. (laog, isos, similar ; Kap&a, cardia, heart.) 
Fam. Cardiacea, Lam. Chamacea, Bl. — Descr. Cordiform, regular, 
equivalve, ventricose, with distant, diverging, involute, free urn- 
bones ; hinge with two compressed cardinal, and one distant, 
compressed lateral teeth in each valve ; ligament external, bifid, 
diverging in the direction of the umbones. — Obs. The shells com- 
posing this genus are remarkable for the beautiful curvature of 
the diverging umbones. European and Chinese Seas. Fig. 126, 
I. Moltkiana. 

KEEL. A flattened ridge, resembling the keel of a ship. As that 
on the back of Carinaria vitrea, fig. 488, and those on the whorls 
of some spiral shells. A shell characterized by a keel or keels is 
said to be carinated. 

KELLIA. Turton. Mya Suborbicularis, Montague. 

LABIS. Oken. Monodonta, Lam. 

LABIUM, or inner lip, — -is used to express that side of the 
aperture which is nearest to the axis and generally contiguous to 
the body whorl. The lower part of this, when sufficiently dis- 
tinct from that part which overwraps the body whorl, is called the 
Columella. 

LAB RUM, or outer lip, — is the edge of the aperture at the greatest 
distance from the axis. 

LACINEA. Humph. Chama, Lam. 

LACUNA. Turt. Fam. Turbinacea, Lam.— Descr. Globose, 
thin, covered with a smooth epidermis ; spire short, consisting of 
few rapidly increasing whorls ; aperture semilunar, rounded at the 



LANISTES. 169 

extremities ; columella oblique, reflected over part of the umbilicus ; 
umbilicus forming a lengthened areabehind the columella. Northern 
shores. Fig 364, L. Pallidula. 
LAGENULA. Montf. A genus of microscopic Foraminifera. 
LAMELLATED. {Lamella, a thin plate.) When the layers of 
which a shell is composed, instead of being compacted into a 
solid mass, are separated, overlying each other in the manner of 
tiles, with the edges prominent, the structure is said to be lamel- 
lated or foliaceous. 
LAMELLIBRANCHIATA. Bl. The third order of the class 
Acephalophora, Bl. consisting of bivalve shells, divided into the 
families Ostracea, Subostracea, Margaritacea, Mytilacea, Polydon- 
tes, Submytilacea, Chamacea, Conchacea, Pylorides, Adesmacea. 
LAMELLIPEDES. Lam. {Lamella, a thin plate, pes, a foot.) 
The third section of the order Conchifera Dimyaria, containing 
bivalves, with the foot of the animal broad and thin ; divided into 
the families Conchacea, Cardiacea, Arcacea, Trigonacea, Nayades. 
Fig. 111. to 152. 
LAMPAS. Montf. Lenticulina, Bl. A genus of microscopic 

Foraminifera. 
LAMPRODOMA. Sw. A genus of " Olivinee," Sw. thus described : 
— " Mitriform ; spire produced, conic ; resembling Mitrella in 
shape, but the suture is channelled ; the aperture effuse at 
the base, contracted above ; lower half of the pillar with 6 to 7 
plaits. Volutella, Zool. 111. ii. series, pi. 40. f. 1. (fig. 86.)" 
Sw.p.321. 
LAMPROSCAPHA. Sw. A sub-genus of " Anodontime," Sw. 
thus described : —" Shell not winged, elongate, pod-shaped ; teeth 
none ; bosses near the anterior extremity. Tropical America 
only? L. ? elongata. Sw. Zool. 111. i. 176. ensiforme, Spix. 
Braz. Test, siliquosa. Braz. Test, pygmeea. lb." Sw. p. 381. 
LAMPROSTOMA. Sw. A sub-genus of Canthorbis (Trochus), 

described at p. 350, Lardn. Cyclop. Malac. 
LAMPUS. Humph. Terebratula, Lam. 
LANCEOLATE. Lengthened like a lance. 
LANISTES. Montf. Reversed species of Ampullaria, fig. 319. 



170 LENGTH. 

LAPLYSIA. See Aplysia. 

LAPLYSIACEA. Lam. (properly Aplysiacea ) A family belonging 
to the first section of the order Gasteropoda, Lam. containing the 
genera Aplysia and Dolabella. Fig. 254, 255. 

LARVA. Humph. Fissurella, Lam. 

LATERAL. (Latus, a side.) The lateral teeth are those which, 
taking their rise near the umbones, proceed to some distance 
towards the sides of the shell ; as distinguished from the cardinal 
teeth, which receive their full developement close to the um- 
bones. Lateral muscular impressions are those which are placed 
at a distance from each other, on the opposite sides of the 
shell. 

LATIAXIS. Sw. A genus of " Eburninse/' Sw. corresponding 
with the genus Trichotropis. Sow. (Sw. Malac. p. 306.) 

LATIRUS. Montf. A genus composed of species of Fusus, 
Auct. which have an umbilicus and are turriculated. 

LAURTA. Gray. A sub-genus of Pupa, containing P. umbilicata, 
&c. (Gray's Turton, p. 193.) 

LEGUMINARIA. Schum. A genus composed of species of 
Solen, Auct. which have an internal longitudinal bar or rib. 
Fig. 61. S. Radiatus, Lam. 

LEILA. Gray ? Described as having the hinge edge smooth 
like Iridina, but having a u sharp siphonal inflexion." (Syn. 
B. M. p. 142.) 

LEIODOMUS. Sw. A genus of " Buccinin8e, ,, Sw. consisting 
of Terebra vittata and other similar species. This genus corres- 
ponds with Bullia, Gray. 

LEIOSTOMA. Sw. A genus of "Fusinse," Sw. thus described, 
"Equally fusiform," (with Fusus) "but ventricose in the 
middle ; shell entirely smooth , almost polished ; inner lip 
thickened, and vitreous ; base of the pillar very straight. Fossil 
only. (fig. 75.) L. bulbiformis. En. Meth. 428. f. 1." 

LEMBULUS. Leach. A genus composed of oval species of 
Nucula, resembling N. margaritacea, fig. 137. 

LENDIX. Humph. Pupa, Lam. 

LENGTH. See Measurement. 



LEPTON. 171 

LENTICULAR. (Lens.) Of a circular, convex form, as Pectun- 
cuius, fig. 134. 

LENTICULINA. Lam. A genus of microscopic Foraminifera. — 
Descr. Lenticular, sub-discoidal, compressed, convolute, sym- 
metrical ; aperture notched ; chambers few in number ; visible 
on the exterior, radiating from the centre of the disk. 

LEPADICEA. Bl. The first family of the class Nemantopoda, 
Bl. This family consists of the same animals which constitute 
the Pedunculated Cirripedes of Lamarck, and part of the genus 
Lepas in the system of Linnaeus. It contains the genera 
Gymnolepas, Pentalepas, Polylepas and Litholepas. 

LEPAS. (Af7rae, lepas, a rock.) The Linnsean name Lepas 
contains all the Cirripedes or Multivalves, the different kinds of 
which are not distinguished in the accounts given by early 
writers of the habits of the animals. (Fig. 14 to 43.) It was 
formerly applied to the Limpets or Patella. In fact, the ancient 
definition was ** Concha petrae adhserens," and would apply to 
any shells attached to rocks. 

LEPTJENA. Dalman. A genus belonging to the Brachiopoda ; 
and thus described : — ' ' Hinge compressed, rectilinear, frequently 
exceeding the width of the shell.' ' It forms part of the genus 
Producta, Sow. Fig. 206, L. depressa. 

LEPTOCONCHUS. Ruppell. (Aevtos, leptus, thin ; Koy X oc, 
conchos, shell.) This shell resembles a young Magilus in general 
appearance, although the animal is said to differ. In the young 
Magilus also, the inner lip is reflected over the body whorl, which 
is not the case in Leptoconchus. Red Sea. Fig. 11. 

LEPTOCONUS. Sw. A sub-genus of Conus, consisting of Conus 
grandis, amadis, duplicatus, Australis, &c. Sw. p. 312. 

LEPTOLIMNEA. Sw. A sub-genus of Limnea, described as being 
nearly cylindrical. Limnea elongata, Sow. Gen. fig. 6. 

LEPTON. Turton. Solen Squamosus, Montague, and other species 
described as "flat, nearly orbicular, equivalve, inequilateral, a 
little open at the sides. Hinge of one valve with a single tooth, 
and a transverse linear lateral one on each side ; of the other 
valve, with a cavity in the middle and a transverse deeply cloven 



172 LIGULA. 

lateral tooth each side, the segments of which divaricate from the 
beak." To represent this genus we have figured L. Squamosum 
in the plates, fig. 62. British. 

LEPTOSPIRA. Sw. A sub-genus of Bulinus, thus described : 
(i Spire excessively long, sub-cylindrical ; body whorl largest ; 
outer lip thickened; aperture oval ; no teeth, striata, Sw. Chem. 
135. f. 1226. signata Sw.' y Sw. p. 335. 

LEUCOSTOMA. Sw. A genus of " Achatina," Sw. described as 
resembling Achatinella, but having a " thick pad" at the top of 
the iS upper lip," and another over the base. L. variegata, Sw. 
Lardn. Cyclop. Malac. fig. 24. p. 172. 

LEUCOTUS. Sw. A sub-genus of Natica, described as interme- 
diate between Sigaretus and Lacuna. Sigaretus cancellatus, 
Lam. (Sw. Malac. p. 346.) 

LICTUM. Humph. Ovula, Lam. (Ovulum.) 

LIGAMENT. (From Ligo, to bind.) The true ligament is always 
external, and serves the purpose of binding the two valves of a 
shell together externally by the posterior dorsal margins. There 
is another substance, called by Gray the Cartilage, which is 
elastic and of a condensed fibrous structure, placed within the 
ligament, either close to it, or at a more interior part of the shell ; 
it is sometimes contained in a pit, formed for its reception, in 
the centre of the hinge. This substance, being elastic, keeps the 
valves open, unless drawn together by the counteracting force of 
the adductor muscles. When conchologists speak of a shell as 
having the ligament external, the real meaning is that these two 
substances are so close together as in appearance to constitute one 
body placed outside the shell so as to be seen when the valves are 
closed. When two ligaments are spoken of, as in Amphidesma, 
the meaning is that the cartilage occupies a separate place on the 
hinge. 

LIGAMENT1FEROUS. (Ligamentum, a ligament, fero, to bear.) 
Having or containing the ligament, as the cardinal pit in Mya, 
fig. 71. 

LIGULA. Leach. A genus containing the more rounded and less 
gaping species of Lutraria, Auct. Fig. 77, Lutraria Papyracea. 



LIMACINEA. 173 

LIGULATE. (Ligula, a slip, a shoe-latchet.) Thin, slender, like 
a slip, or neck of any thing, as the anterior muscular impression 
of Lucina, fig. 104. 

LIGUMIA. Sw. A sub-genus of Unio, thus described : — " Very 
long and pod -shaped ; bosses depressed; cardinal teeth mode- 
rate. S. recta. Lam. vi. 1. p. 74." Sw. p. 378. 

LTGUUS. Montf. A genus containing species of Achatina, 
Auct. which have rounded apertures and lengthened spires, dif- 
fering from his Polyphemi, which have lengthened apertures. 
A. virginea, Auct. fig. 286, is the type of this genus. 

LIMA. Brug. (Lima, a file.) Fam. Pectinides, Lam. Subos- 
tracea, Bl. — Descr. Equivalve, inequilateral, compressed, oblique- 
auriculated, oval, radiately ribbed or striated, imbricated, covered 
with a light brown epidermis ; hinge with a triangular disc between 
the umbones, divided in the centre by a triangular ligamentary pit 
without teeth ; muscular impression one, sublateral, sub-orbi- 
cular. — Obs. The shells thus described are marine, two or three 
species being found on our coasts, and fossil species occurring in 
Lias, inferior Oolite, Calcaire-grossier, &c. They differ from 
Pecten in having a wide hiatus for the passage of a byssus, by 
which they are occasionally attached, and also in the triangular 
disc, which separates the umbones. The animal makes use of 
the valves of his shell as natatory organs, working them like fins 
or paddles, and by this means proceeding at a rapid rate through 
the waters. L. Squamosa, fig. 174. 

LIMACINA. Cuv. (Limax, a snail.) Fam. Pteropoda, Lam.— 
Descr. Papyraceous, fragile, planorbicular, sub-carinated, ob- 
liquely convolute ; spiral side rather prominent, the other side 
umbilicated ; aperture large, entire, not modified, peristome 
sharp. — Obs. This is Spiratella, Bl. The shell figured as 
Limacina in Sowerby's Genera, under " pteropoda," is an Atlanta. 
Our representation of Spiratella Limacinea, fig. 224. is copied 
from Blainville. 

LIMACINEA. Lam. A family of the order Gasteropoda, Lam. 
including the following genera: — 



174 LIMNEA. 

1. Cryptella. Spire mammillated ; a septum. Fig. 256. 

2. Parmacella. Flat, haliotoid, spiral. Fig. 257, 258. 

3. Testacellus. Sub-spiral. Fig. 261. 

4. Li max. Incomplete. Fig. 259. 

5. Plectrophortjs. Conical. Fig. 260. 

6. Vitrina. Heliciform, hyaline. Fig. 262, 263. 
LIMACINE A. Bl. The third family of the order Pulmobranchiata, 

Bl. Described as containing shells very variable in form, most 
frequently incliniDgto globular or oval ; the apex always obtuse ; 
aperture variable, but never emarginated. All the Limacinea 
are phytophagous and terrestrial. This family answers to the 
genus Helix of Linnaeus and to the Colimacea of Lamarck, leaving 
out the Auriculacea. It contains the genera Succinea, Bulinus, 
Achatina, Clausilia, Pupa, Partula, Helix, Vitrina, Testacella, 
Limacella, Limax. 

LIMAX. Lam. Limacinea, Lam. and Bl. — Descr. Internal irre- 
gular, sub-quadrate, scutiform, crystalline ; apex rounded, in- 
distinct ; epidermis, light brown, thin, extending beyond the 
margin. — Obs. The shell is placed under the scutellum of the 
common garden slug. Fig. 25, L. Antiquorum. 

LIMNACEA. Bl. The first family of the order Pulmobranchiata, 
Bl. The shells of this family are described as thin, with the 
outer lip always sharp. It contains the genera Limnea, Physa, 
Planorbis. 

LIMNEANA. Lam. A family of the order Trachelipoda, Lam. 
containing the following genera: — 

1. Limn^ea. Spire produced ; including Physa. Fig. 308 
to 310. 

2. Planorbis. Spire orbicular ; including Planaria. Fig. 
311, 312. 

LIMNEA. Lam. (Aifivag, limnas, lacustrine.) Fam. Limnacea, Lam. 
and Bl. — Descr. Oblong, light, thin; spire variable in length, 
acute ; last whorl large, aperture large, longitudinal, entire ; inner 
lip spread over a portion of the last whorl ; columella forming an 
oblique fold ; outer lip rounded at each extremity, thin. — Obs. 



LITHODOMUS. 175 

These light horn-coloured shells are common in standing pools, 
ponds and ditches, in various parts of Europe. They resemble 
the Amber shell (Succinea) in shape, but the animal of the latter 
is amphibious, and the shell of a bright amber colour. L. 
Stagnalis, fig. 308. L. auricularia, fig. 309. (Radix, Montf.) 
The reversed species have been separated under the name Physa, 
fig. 310. Other generic names have been given to other species. 
LINES OF GROWTH. The concentric striae or lines formed by the 
edges of the successive layers of shelly matter deposited by the 
animal by which it increases the shell. The outer edge of the 
aperture is always the last line of growth. 
LINGUIFORM. {Lingua, tongue ; forma, form.) Tongue-shaped. 
LINGULA. Lam. (Dim. from lingua, tongue.) Fam. Brachio- 
poda, Lam. Palliobranchiata, Bl. — Descr. Equivalve, oblong, 
depressed, thin, equilateral, gaping and pointed at the umbones, 
gaping and truncate or trilobate at the opposite extremities, 
attached by a fleshy pedicule fixed to the umbones. — Obs. This 
is the only bivalve shell which is pedunculated, in which respect 
it constitutes a singular anomaly. The ancient writers, seeing 
the valves separate, placed it in their systems under the name 
Patella Unguis. There are several recent species found in the 
Moluccas, and some fossils in sandy indurated marl, and in 
alluvium of Suffolk. L. Anatina, fig. 219, is so named from its 
resemblance to a duck's bill. 
LINGULINA. D'Orb. A genus of microscopic Foraminifera. 
LINTHURIS. Montf. Conch. Syst. 2. 154. A genus of micro- 
scopic Foraminifera. 
LIP. See Labium and Labrtjm. 

LIPPISTES. Montf. A genus of microscopic Foraminifera. 
LITHODOMUS. Cuv. (At0oe, lithos, stone ; Aw/ki, doma, house.) 
Fam. Mytilacea, Lam. — Descr. Transverse, elongated, cylindri- 
cal, equivalve, with the extremities rounded, and the posterior 
extremity rostrated ; umbones not prominent, terminal ; hinge 
straight, destitute of teeth ; ligament linear, most conspicuous 
within; muscular impressions two. — Obs. The shells composing 



176 LITIOPA. 

this genus differ from Modiola, not only in the cylindrical form, 
but also in the circumstance from which the generic name is 
derived, i. e. of their living in stones. Thus, while the form and 
structure of the shell bring it near the Mytili or Muscle shells, 
the habits of the animal cause it to approach the Lithophagi, or 
rock-eating molluscs of Lamarck. L. Dactylus (fig. 161,) is the 
Mytilus Lithophagus of ancient authors. 

LITHOLEPAS. Bl. (Aidog, Uthos, stone, A£7mc, lepas, rock.) De 
Blainville's name for Lithotrya, Sow. 

LITHOPHAGIDiE. Lam. (Ai0oe, lithos, stone ; 3>ayw, phaga y 
eat or gnaw.) A family of the Conchifera Dimyaria, Lam. 
consisting of terebrating bivalves, gaping anteriorly, having no 
accessary valves ; and containing the genera Saxicava, Petricola, 
Venerupis, to which are added other genera enumerated in 
explanation of figures 91 to 97. Notwithstanding the numerous 
genera which have been created, I think that the most convenient 
arrangement will be to reduce them to two, thus — 

1. Petricola, with distinct cardinal teeth, including, Clothe, 
Venerirupis and Coralliophaga. Fig. 91, 92, 97. 

2. Saxicava, without teeth, including Biapholius, Hiatella, 
Sphsenia, Byssomya, and Thracia. Fig. 93 to 96. 

LITHOTRYA. G. B. Sowerby. (Aidoe, lithos, stone ; rpvw, truo, 
to bore through.) Fam. Pedunculated Cirripedes, Lam. — Descr. 
Eight unequal valves, forming a laterally compressed cone, the 
lower central valves being very minute ; pedicle fleshy, scaly at 
the upper extremity ; fixed at the base in a patelliform shelly 
support. — Obs. This genus derives its name from the power 
possessed by the animal of making dwelling holes in stones or 
pieces of rock. The remarkable shelly cups at the base of the 
pedicle is regarded as analogous to the shelly base of the Balanus, 
so that this genus would form an intermediate link between the 
Sessile and Pedunculated Cirripedes of Lamarck. Fig. 39, L. 
dorsalis. West India Islands. 

LITIOPA. Ranz. Fam. Turbinacea, Lam. — Descr. "Shell not 
very thick, horny, with a slight epidermis, rather transparent, 



LITUACEA. 177 

conical, with whorls somewhat rounded ; the last being larger 
than all the rest together ; with the apex pointed, longitudinally 
grooved ; aperture oval, larger anteriorly than posteriorly, with 
the lips disunited, the right lip simple, separated from the left 
by a rather indistinct notch, or a slight emargination in the 
contour. The left lip slightly reflected backwards, so as to form 
a kind of salient margin with the anterior extremity of the 
columella, which is united, rounded, arcuated and slightly 
truncated at the anterior." — Obs. The Molluscous animals, whose 
shells are thus described, are found in the Mediterranean , and 
are remarkable for the power of suspending themselves from 
the sea-weed on which they live, by a thread resembling a spider's 
web. The general appearance of the shell presents a medium 
between Phasianella and Littorina, but it is apparently destitute 
of an operculum. 

LITTORINA. Fer. (Littus, the sea-shore.) Fam. Turbinacea, 
Lam. — Descr. Turbinated, thick ; spire acuminated, consisting 
of few whorls, about one third of the axis in length ; aperture 
entire, large, rounded anteriorly; outer lip thickened within, 
acute ; columella rather flattened ; operculum horny, spiral, with 
rapidly increasing volutions. — Obs. The shells composing this 
genus are known from Turbo and Phasianella by the horny 
operculum ; and from Trochus, which has also a horny opercu- 
lum, by the small number of the whorls. The Littorinse, among 
which may be enumerated the common Periwinkle, are, as the 
name implies, found on sea shores, feeding upon seaweed, in all 
parts of the world. Fig. 363, L. Vulgaris. 

LITUACEA. Bl. The second family of Polythalamacea. Bl. The 
shells are described as chambered, symmetrical, convolute in part 
of their extent, but constantly straight towards the termination. 
The genus Spirula, which is admitted into this family, does not 
properly belong to it, any more than to the Lituolse of Lamarck, 
in which it is also placed. It does not agree with the descriptions 
of either. This family partly corresponds with the " Lituolees," 



178 LORIPEDES. 

Lam, and contains the genera Lituola, Ichthyosarcolites, Spirula, 
Hamites and Amraonoceras. 

LITUACEA. Lam. A family of the order Polythalamous Cephalo- 
poda, Lam. containing the genus Spirula, fig. 471. 

LITUITUS. Montf. Spirolina, Lam. Microscopic. 

LITUOLA. Lam. A genus of microscopic Foraminifera. 

LITUOLA. Lam. The third family of Polythalamous Cephalo- 
poda, Lam. the shells of which are described as partially spiral, 
the last whorl continuing in a straight line. The transverse septa 
which divide the chambers, are in general pierced by a siphon 
which breaks itself off before it reaches the succeeding septum. 
This family contains the genera of microscopic Foraminifera 
Lituola and Spirolina. The genus Spirula, also placed in this 
family, does not by any means agree with Lamarck's definitions 
"the last whorl continuing in a straight line." 

LITUUS. Humph. Cyclostoma ? Lam. 

LIVID. (From lividus.) Of a pale, dull, blue colour. The adjec- 
tive is sometimes used as a specific name. Ex. Conus lividus, 
Sanguinolaria livida. 

LOBABIA. Schum. Sanguinolaria rosea, Lam. (fig. 98) and 
other similar species. 

LOBATE or LOBED. Divided into parts. 

LOBATULA. Fleming. A genus composed of two very minute 
species of chambered shells. Serpula lobata and S. concamerata, 
Mont. Test. Brit. 515. 

LOMASTOMA. Rafinesque. An imperfectly defined genus, pro- 
bably belonging to the Limnacea. 

LONGITUDINAL. Lengthwise. Longitudinal striae, ribs, &c. 
are those which radiate from the apex and follow the spiral 
direction of the whorls, in spiral shells ; and from the umbo to 
the ventral margin in bivalves. The term " decourantes'' is 
employed by French conch ologists. The bands in Achatina, fig. 
286, are longitudinal or spiral. 

LORIPEDES. Poli. A genus composed of species of Lucina, Auct. 
in which the lunules are not prominent. 



LUPONIA. 1/9 

LOTORIUM. Montf. A genus composed of species of Triton, 
Auct. in which the aperture is effuse. T. Lotorium, fig. 400. 

LOTTIA. Gray. Patelloida, Quoy and Gaimard. 

LUCERNA. Humph. A generic name applied to some species of 
Helix included inDe Ferussac's sub-genus Helicogena. 

LUCERNELLA. Sw. A genus of " Lucerninse," Sw. thus des- 
cribed: i( Teeth on both sides of the aperture; surface regularly 
and distinctly striated. Circumference convex." 

LUCIDULA. Sw. A sub-genus of Lucerna, Humph, thus described: 
" Aperture transverse, both lips much thickened and united; the 
outer with marginal obsolete teeth at the base; umbilicus closed. 
Barbadensis, Lam. No. 49. p. 78. Fer. Moll. pi. 47, 2, 3, 4." 

LUCINA. Brug. Fam. Nymphacea, Lam. Conchacea, Bl. — 
Descr. Equivalve, inequilateral, orbicular, lenticular, radiately 
striated ; hinge with, generally, two minute cardinal teeth, which 
are sometimes nearly obsolete, and two lateral teeth, on each 
side of the umbo in one valve, one in the other ; ligament exter- 
nal, partly hidden by the margins of the valves when closed. 
Muscular impressions two in each valve, the anterior one pro- 
duced into an elongated, ligulate band, the posterior short and 
semi-rotund; impression of the mantle not sinuated. — Obs. The 
shells of this genus resemble Amphidesma in general form, but 
are distinguished by the external ligament, the elongated mus- 
cular impression, and the want of a sinus in the palleal impres- 
sion. East and West Indies, and European shores. Fig. 104, 
L. Tigerina. 

LUNULATE. (Luna, the moon, dim.) Moon-shaped, having 
the form of a crescent. Applied most frequently to muscular 
impressions. Semilunar is sometimes used, perhaps with greater 
accuracy, to express the same shape. 
LUNULE. An impression on the anterior dorsal margin of some 
bivalve shells. The similar impression on the posterior dorsal 
margin is called the escutcheon. 
LUPONIA. Gray. A genus composed of species of Cypr^ea, 
Auct. which are described as having the anterior of the columellar 
n 2 



180 MACRODITUS. 

lip crossed by several irregular ridges, without any distinct mar- 
ginal ones, internally narrow, flat ; the shell pear-shaped, 
smooth, or cross-ribbed. Ex. C. Algoensis, Luponia Algoensis, 
Gray, fig. 447. 

LUTRARIA. Auct. (Lutum? mud.) — Fam. Mactracea, Lam. — 
Descr. Thin, equivalve, inequilateral, transverse, oblong or ovate, 
gaping at both extremities ; hinge with one double and some- 
times one single cardinal tooth in each valve, and a triangular, 
oblique pit with a prominent margin, containing the ligament; 
muscular impressions distant ; palleal impression having a large 
sinus. — Obs. This genus differs from Mactra in the entire absence 
or indistinctness of lateral teeth. Fig. 77, L. Papyracea. (Ligula, 
Leach.) Fig. 78. L. Solenoides. Sandy and muddy shores. 

LUTRICOLA. Bl. Lutraria. Lam. Fig. 77, 78. 

LYCOPHRIS. Montf. A microscopic fossil described as resem- 
bling Nummulites, but having a granulated surface. 

LYMNADEA. Sw. A sub-genus of " Mysca," Turton, in the 
family of Nayades, Lam. thus described : " Posterior hinge margin 
elevated and winged ; the valves connate ; the surface smooth. 
L. alata Sw. Ex. Conch, (fig. 48.) fragilis. Sw. Zool. 111. com- 
pressa, Lea. Am. Tr. iii. pi. 12. f. 22." Sw. p. 379. 

LYMNEA. See Limnea. 

LYMNEUS. Lam. See Limneana. 

LYON SI A. Turt. Inequivalve species of Anatina, Auct. which 
have no spoon-shaped cavity in the hinge, but an accessary piece. 
L. striata, fig. 491, 2. 

LYRODON. Goldf. Trigonia? 

MACLURITES. Lesuour. Journ. des Scienc. Nat. Philad. t. 1. 
p. 312. pi. 13. fig. 2, 3. 

MACOMA. Leach. Venus tenuis, Bl. and similar species, de- 
scribed as " Clothed with an epidermis; striated, compressed, 
oval; the summits not very prominent; two bifid teeth upon 
the right valve and a single undivided one upon the left." 

MACRODITUS. Montf. Lenticulina, Bl. A genus of micros- 
copic Foraminifera. 



MACTRACEA. 181 

MACROSPIRA. Guild. A genus composed of Helix octona, 
Auct. Macrospira aperta, Guild. 

MACROSTOMATA. Lam. (Ma/cpoe, macros, long ; arofxa, stoma, 
mouth.) A family belonging to the first section of the order 
Trachelipoda, the shells belonging to which are described as 
haliotoid or ear shaped, with a very large aperture, destitute of 
an operculum. This family contains the following genera, which 
maybe thus distinguished. 

1. Velutina. Globose, with velvety epidermis. Fig. 337. 

2. Stomatia. Ear-shaped ; pearly within ; including Sto- 

matella. Fig. 335, 336. 

3. Sigaretus. The same, not pearly ; including Cryptostoma. 
Fig. 334. 

4. Coriocella. The same, thin, transparent. 

5. Haliotis. The same, not thin, nor transparent ; with 

holes ; including Padollus. Fig. 338, 339. 

6. Scissurella. Heliciform, with a slit near the aperture. 
Fig. 340. 

7. Pletjrotomaria. Trochiform, with a slit at the edge of 
the aperture. Fig. 341. 

MACTRA. Auct. (Mactra, a kneading trough.) Fam. Mac- 
tracea, Lam. Conchacea, Bl. — Descr. Usually thin, equivalve, 
sub-equilateral, sub-trigonal, slightly gaping at the extremities ; 
hinge with one cardinal tooth, divided into two parts, diverging 
from the umbo, with sometimes a very small laminar tooth close 
to its side ; a deep triangular pit near the centre, containing the 
cartilage ; one long, lateral tooth on each side of the umbo in 
one valve, received between two in the other ; muscular impres- 
sions two, lateral ; palleal impression with a small sinus. — Obs. 
This genus contains many species of beautiful shells found in 
various parts of the world, some are common in Britain. Fossil 
species are not numerous, they occur in the tertiary strata. 
Fig. 79 to 82. 

MACTRACEA. Lam. A family of the order Conchifera Dim yaria, 
Lam. Sect. Tenuipedes. The cartilage placed in a trigonal 



182 MAGILUS. 

pit with a small external ligament. The genera may be ^hus 
distinguished. 

1. Lutraria. No lateral teeth, shell gaping. The short 

species constitute the genus Ligula. Fig. 77, 78. 

2. Mactra. Lateral teeth, shell closed. This genus has 
been divided into Mactra, Mulinia, Schizodesma and Spi- 
sula, by Mr. Gray. Fig. 79 to 82. 

3. Gnathodon. Teeth serrated, thick, one angular. Fig. 83. 

4. Crassatella. Shell thick, lateral teeth. Fig. 84. 

5. Amphidesma. A distinct external ligament, internal liga- 
ment oblique. Fig. 85. 

6. Erycina. A short tooth on each side of the cartilaginous 
pit in each valve. Including Mesodesma. Fig. 86. 

7. Ungulina. Ligament flat, divided. Fig. 88. 
MACULATED. (From Macula, a spot.) Spotted or patched. 

This term is applied by conchological writers, to those shells 
which are coloured in spots or small patches. In the same sense 
it is also used as a specific name. As for instance, Cytherea 
maculata, fig. 167, c and Hippopus maculatus, fig. 156. 

MAGAS. Sow. (Mayas, magas, a board, a deck.) Fam. Brachio- 
poda, Lam. — Descr. Equilateral, inequivalve ; one valve convex, 
with a triangular area, divided by an angular sinus in the centre ; 
the other valve flat, with a straight hinge line and two small 
projections ; a partial longitudinal septum, with appendages 
attached to the hinge within. Differing from Terebratula in 
having a triangular disc, and not a circular perforation. Magas 
pumilus, fig. 299. Fossil in chalk. 

MAGILUS. Montf. Fam. Cricostomata, Bl. Serpulacea, Lam. — 
Descr. Thick, tubular, irregular, contorted ; rounded above, 
keeled beneath, free ; apicial extremity convolute, heliciform, 
ovate or sub-globose; aperture elliptical. — Obs. This shell when 
in a young state presents the characteristics of a regularly formed 
spiral univalve, living in holes in madrepores. As the madrepore 
increases in bulk, the animal gives an eccentric course to the 
shell, in order to have its aperture even with the surface, and 



MALLEUS. 183 

leaving the nucleus or young shell behind, fills it up with calca- 
reous matter to reside in the open extremity of the tube. Fig. 
9, 10. Red Sea and Mauritius. 

MALACOTA. Schum. Otion. Leach. 

MALACOZOA. Bl. (MaXaicog, malacos, soft ; Zuov, zoon, animal.) 
The type or general appellative in De Blainville's system, including 
all molluscous animals, excepting those with multivalve shells. 

MALDANIA. Lam. The second family of the order Annelides 
Sedentaria. The only genus of shells described in this family is 
Dentalium, fig. 2, to which may be added Pharetrium, Konig. 
fig. 3. It is doubtful however whether the latter do not belong 
to an unknown genus of Pteropodous Mollusea. 

MALEA. Valenciennes. A genus composed of Dolium latilabrum, 
Kiener, and other similar species. 

MALENTOZOA. Bl. (MaXctKog, malacos, soft ; zv, in, re/iva), 
t em-no, cut ; Zwov, zoon, animal.) Or articulated mollusea. The 
sub-type in De Blainville's system, comprehending those with 
multivalve shells. 

MALLEACEA. Lam. A family belonging to the order of Conchi- 
fera Monomyaria. Containing the following genera of irregular 
pearly bivalves. 

1. Avicula. Hinge linear, simple, including Meleagrina. 

Fig. 163, 164. 

2. Pern a. Hinge with linear grooves, including Pulvinites. 

Fig. 166, 170. 

3. Gervillia. Shaped like Modiol a, with irregular grooves. 
Fig. 162. 

4. Crenatula. Hinge with a series of pits. Fig. 168. 

5. Catillus. Like Perna, but more regular and convex. 

Fig. 167- 

6. Malleus. A triangular disc on the hinge, and two auricles. 
Fig. 165. 

MALLEUS. Auct. {Malleus, a hammer.) Fam. Malleacea, 
Lam. Margaritacea, Bl. — Descr. Equivalve, inequilateral, folia- 
ceous, trilobate, undulated, irregular, attached by a byssus 



184 MARGINAL. 

passing through a sinus in one valve ; hinge rectilinear, length- 
ened by two auricles ; with a small disc under the umbones, 
containing the ligament, and a groove containing the cartilage ; 
muscular impressions one in each valve, large, uniform, and one 
or two others extremely minute. — Obs. Malleus Vulgaris, the 
type of this genus, is a most singular shell, commonly called the 
" Hammer Oyster," from the peculiarity of its shape. It belongs 
to the Linnsean genus Ostrea, from which it differs in being 
attached by a byssus. Fig. 165, M. Vulgaris. Tropical. 

MAMILLARIA. Sw. A sub genus of Nattca, corresponding with 
Polinices of Montfort, having the spire small and the umbilicus 
filled. Ex. Natica Mamilla, Auct. fig. 327. 

MAMMILLATED. (Mammula, a little teat.) A term applied to 
the apex of a shell when it is rounded like a teat. Ex. Voluta 
Vespertilio, fig. 433. 

MARGARITA. Leach. (Margarita, a pearl.) A genus of small 
shells resembling the genus Trochus, from which it differs in 
having an operculum consisting of few whorls. M. taeniata, fig. 
362. Mr. G. B. Sowerby, sen. has enumerated 15 species in a 
list accompanying the figures published by the author of this 
manual in Nos. 132 to 134 of his Conchological Illustrations. 

MARGARITACEA. Bl. The third family of Lamellibranchiata, Bl. 
The shells belonging to it are described as irregular, inequivalve, 
inequilateral, black or horny without, pearly within ; hinge 
auriculated, scarcely developed, and without teeth. The ligament 
is variable and there is a large sub-central muscular impres- 
sion. This family contains the genera Vulsella, Malleus, Pinna, 
Crenatula, Inoceramus, Catillus, Pulvinites, Gervillia and Avicula. 

MARGARITACEOUS. (Margarita, a pearl.) Pearly. 

MARGARITANA. Schum. A sub -genus of Uniones, composed 
of species having " one cardinal tooth." Alasmodon, Say. Mya 
Margaritifera, Linn. 

MARGARITIFEROUS. (Margarita, pearl ; fero, to bear.) Pearl- 
bearing. Applied to shells which form pearls ; as Meleagrina 
Margaritifera, or Pearl- bearing Oyster. 

MARGINAL. Near the margin or edge. 



MARPESSA. 185 

MARGINATED. (Margo % edge.) Having an edge or border 
thicker than the rest of the shell, from which circumstance the 
litle genus Marginella derives its name. 

MARGINELLA. (A little rim or border.) Fam Columellaria, 
Lam. Angyostomata, Bl.— Bescr. Ovate, smooth, shining, with 
a short, sometimes hidden spire ; aperture narrow, emarginated ; 
columella with several oblique folds ; outer lip neatly reflected. 
— Obs. This genus of pretty little shells differs from Voluta, in 
the reflection of the outer lip. The animal covers the greater 
part of the shell with the mantle, and by continually depositing 
vitreous matter gives it a bright polish, which, together with the 
delicately neat arrangement of colours in most species, renders 
them exceedingly beautiful. The Marginellse are marine and 
tropical. A few fossil species are found in the Calc-grossier. 
Fig. 437. M. Glabella. Glabella, Sw. 

MARGINULINAi D'Orb. A genus of microscopic Foraminifera. 

MARINE CONCHACEA. See Conchacea. 

MARINE TESTACEA. Those sheli-fish which inhabit seas, lakes, 
&c. of salt water, in distinction from the Aquatic Testacea, or 
those which are found in rivers, ponds or stagnant pools of fresh 
water : and also from the Land Testacea, which live on land and 
breathe air. The great proportion of shells belong to the former 
class, those of the latter two classes being limited in their number, 
and in the genera to which they belong. 

MARINULA. King. A genus of small shells resembling Auricula 
and Pedipes, described as " Ovate, sub-solid, with aperture ovate 
entire ; columella bidentate, uniplicated towards the base, with 
large sub-remote teeth ; the largest uppermost ; no operculum." 

MARMAROSTOMA. Sw. A genus of « Trochidae," Sw. thus 
described : " Umbilicus deep ; spire of few whorls, much depres- 
sed, and obtuse ; inner lip obsolete -, base even more produced 
than in Senectus, but never distinctly channeled. M. versicolor. 
Mont. 176. f. 1740, 1741, undulata. Chem. 169. f. 1640, 1641," 
Sw. p 348. 

MARPESSA. Gray. A sub-genus of Clausilia, C. bidens, &c. 
Auct. Gray's Turton, p. 212. 



186 MEGALOMASTOMA. 

MARTESIA. Leach. A genus composed of those species of Pho- 
las, Auct. which are described as short, cuneiform, nearly 
closed at both extremities, having several accessary pieces on the 
middle of the back, and two marginal, lower down. 

MEASUREMENT. The most approved method of stating the 
measurements of various kinds of shells is as follows : symme- 
trical convolute univalves, the length is from anterior to posterior ; 
the depth from ventral to dorsal ; the breadth, from side to side 
of the aperture. Of symmetrical conical univalves, length, from 
front to back ; breadth from side to side ; depth from apex to 
base. Of spiral univalves, length, from apex to anterior of the 
columella or axis of the shell ; breadth, across from the outer lip 
to the opposite side. Of non- symmetrical bivalves, the length is 
from the anterior to the posterior margin ; breadth, from the 
greatest convexity of one valve to the corresponding part of the 
other ; depth, from the ventral to the dorsal margin. 

MEGADESMA. Bowd. (Meyae, megas, great ; Ita^a, desma, 
ligament.) Potamophila, Sow. Galath^a, Lam. 

MEGADOMUS. Sw. A sub-genus of Unio, thus described : 
" Only one lateral tooth in each valve ; cardinal teeth two ; 
posterior hinge margin winged. M. gigas, *SW Sw. p. 3/8. 

MEGALODON. Sow. (Meyac, megas, great ; odog, odos, tooth.) 
Fam. Cardiacea, Lam. — Descr, Equivalve, longitudinal, acumi- 
nated at the umbones, thick ; hinge forming an incrassated septum 
across the cavity of the shell, with a large bifid tooth in the 
right valve, and one irregular and one pointed in the left ; liga- 
ment long, external. — Obs. The general form, the thickened 
hinge reaching across the cavity of the valve and the terminal 
umbones serve to distinguish this genus from Cardita, to which, 
however, it is nearly allied. M. cucullatus, fig. 127. 

MEGALOMASTOMA. Guild. A sub-genus of Cyclostoma, thus 
described : u Cylindrical, resembling Pupa, but has a horny 
operculum ; spire not thickened ; teeth or fold on the pillar none, 
flavulaSw. En. Meth.461. f. 6, brunnea Guild. (Jig.97.g.h. 1.) 
Sw. p. 336. Mr. Gray applies the name to those species which 
have "a groove or ridge in front of the mouth near the pillar/' 






MELANITHES. 18/ 

MEGARIMA. Rafinesque. A genus proposed to include species 
of Terebratula, Auct. which are smooth and nearly equivalve. 
T. lsevis, T. crassa, T. truncula. 

MEGASPIRA. Lea. (Mayas, megas, great, and spire.) M. Ru- 
schenbergiana, (fig. 294) is a pupiform land shell remarkable for 
the length of its spire, which consists of no less than twenty-five 
close set, narrow, gradually increasing whorls. The outer lip is 
simple, slightly thickened ; the inner lip has a tooth on the body- 
whorl, and two folds on the columella. Only one species of this 
singular shell is known. 

MEGATREMA. Leach. A genus composed of those species of 
Pyrgoma, Auct. which have a large aperture. Fig. 33. 

MELACANTHA. Sw. A sub-genus of Melania. Sw. p. 341. 

MELAFUSUS. Sw. A sub-genus of Melanopsis. Sw. p. 34 1 . 

MELAMPUS. Montf. Conovulum, Lam. A genus composed 
of species of Auricula, Auct. of a conical form. A. conoidalis, 
fig. 298. 

MELANIA. Auct. (MeAae, melas, black.) Fam. Melaniens, Lam. 
Ellipsostomata, Bl. — Descr. Turrited ; spire generally elongated, 
acute ; aperture entire, oval or oblong, pointed at the posterior 
extremity, rounded anteriorly, with a kind of indistinct canal or 
sinuosity : epidermis thick, generally black. — Obs. In common 
with other fresh-water shells, the Melaniee are frequently found 
with corroded apices. This genus is known from Melanopsis by 
the absence of the notch at the anterior part of the aperture. 
The Melaniee occur in rivers of warm climates. The fossil species 
are frequent in upper marine formations. Fig. 313, M. subulata. 

MELANIANA. Lam. (Melaniens.) A family belonging to the 
first section of the order Trachelipoda. The genera contained in 
it maybe distinguished as follows. 

1. Melanopsis, Aperture notched ; columellar lip thickened 
above; including Pirena. Fig. 315, 316. 

2. Melania. Aperture not notched ; columellar lip not thick- 
ened ; including Auculosa, Pasithcea, lo. Fig. 313, 314,317. 

MELANITHES. Sw. A sub-genus of Melanopsis. Sw. p. 341. 



188 MELONIA. 

MELANOIDES. Olivier. Melanopsis. Fer. 

MELANOPSIS. Fer. Fam. Melaniana, Lam. Entomostomata, Bl. 
— Descr. Oval or oblong, fusiform; spire acute, sometimes elon- 
gated ; aperture oblong or oval, pyriform, with a distinct notch at 
the anterior extremity ; columella tortuous, callous, thickened at 
the extremity near the spire ; epidermis thick, horny, generally 
black. Subtropical.— Obs. This description includes the two first 
species of the genus Pirena, Lam. The Melanopsides are known 
from the Melanise by the notch in the aperture. Fig. 315. M. 
costata. 

MELAS. Montf. Melania, Auct. 

MELATOMA. Sw. A sub-genus of Melanopsis. Sw. p. 341. 

MELEAGRINA. Lam. Margarita. A genus composed of the 
Pearl Oyster and similar species, separated from Avicula on 
account of the roundness of their general form, but re-united 
by Sowerby. For generic characters, see Avicula. Fig. 164. M. 
margaritifera. 

MELEAGRIS. Montf. Turbo Pica, Auct. and similar species, 
having the aperture oblique, the columella gliding imperceptibly 
into the outer lip, and having an umbilicus. 

MELINA. Schum. Perna, Auet. 

MELO. Brod. (Melo, a melon.) Fam. Columellaria, Lam. — 
Descr. Light, ventricose, oval, with a light greenish brown epi- 
dermis, spire short, papillary, regular, sometimes hidden by the 
last whorl ; aperture large, nearly as long as the whole shell, 
emarginated anteriorly ; outer lip thin ; columella slightly curved, 
with four or five laminar, oblique, prominent plaits. — Obs. The 
genus Melo has been separated from Voluta principally on account 
of the largeness of the aperture, the lightness of the shell and the 
thinness of the outer lip. Melo differs from Cymbain the regula- 
rity of the spiral apex, and in the greater rotundity of the shell. 
The Melons are beautifully coloured large shells, found in the seas 
of the old world. The Melo Indicus has a certain resemblance to 
a Melon. Fig. 435. M .JEthiopicus. 

MELONIA or MELONITES . A genus of microscopic Foraminifera. 



MITRA. 



189 



MERCENARIA. Schum. Venus Mercenaria, Auct. The Money 
shell which passes current for cash, under the name " Wampum," 
among the North American Indians. 

MERETRIX. Lam. Original name for Cytherea, Lam. 

MEROE. Schum. Cytherea Meroe, sulcata, scripta, hians, 
Auct. and similar species. Fig. 1 ] 7, «. 

MESODESMA. Desh. Erycina, Lam. according to G. B. 
Sowerhy. 

MESOMPHYX. Rafinesque. A genus proposed to be separated 
from Helix, Auct. 

MICROTOMA. Sw. A genus of « Purpurinse," Sw. thus de- 
scribed, " Pillar very broad and curving inwards; aperture effuse; 
the notch at the base small and nearly obsolete ; spire very short, 
patula. Mart. 69. f. 758, 759. persica. En. Meth. 397. f. I. 
unicolor. Sw. Chem. f. 1449* Sw. p. 301." Purpura Persica. 
Fig. 414. 

MILIOLA. Lam. A genus of microscopic Foraminifera. 

MISILUS. Montf. A genus of microscopic Foraminifera. 

MITRA. Lam. (Mitre.) Fam. Columellaria, Lam. Angyostomata; 
Bl. — Descr. Oblong, thick, covered with a light brown epidermis; 
spire long, turrited, acute ; aperture emarginated anteriorly; 
outer lip thickened; columella with several oblique, thick plaits. — 
Obs. The pretty small shells composing this genus differ from 
Marginella, not only in general form, but in the outer lip not 
being reflected. Some species of Voluta, of a more elongated 
shape than the rest, present a near approach to the most ven- 
tricose of the Mitree. The apex of Mitra, however, is always 
acute, while that of Voluta is generally papillary. The aperture 
of the former is narrow and the inner lip thickened, the contrary 
being the case with the latter. The shells of this genus are 
varied in colouring which is generally rich ; and also in form, 
some being angulated, some plicated, some coronated and 
others smooth. The species are mostly tropical; very few occur 
so far north as the Mediterranean. Fossil species are numerous 
in the Eocene beds. Fig. 431. M. Plicaria. Fig. 432. Cono- 
helix marmorata, Sw. 



190 MONILEA. 

MITRELLA. Sw. A genus consisting ofMiTRA Fissurella, casta, 
Olivseformis, and similar species, described as " Rather small ; 
olive-shaped; unequally fusiform; always smooth and polished, 
and sometimes covered with an epidermis; base obtuse and effuse; 
spire nearly or quite equal to the aperture; plaits of the pillar 
few, oblique, and extending beyond the aperture, which is 
smooth internally." Sw. p. 321. M. Fissurata, E. M. 371. 
f. 1. Olivarii, f. 2. Dactylus. 372. f. 5. Ex. Mitra bicolor. 

MITREOLA. Sw. A genus of "Mitranse," Sw. thus described : 
u Small; unequally fusiform; the base obtuse; inner lip, typically 
thickened, inflected, and either toothed or tuberculated ; plaits 
on the pillar distinct, the inferior largest ; tip of the spire 
sometimes papillary; aperture without either striae or groove/' 
Sw. p. 320, M. Monodonta, M. Terebellum. Zool. Illustr. II. 
128. f. 1. f.2. 

MODIOLA. Lam. (Modiola, a little measure.) Fam. Mytilacea, 
Lam. — Descr. Equivalve oblique, cuneiform, inequilateral, thin, 
with the anterior side short and narrow, slightly gaping to admit 
the passage of a byssus, and the posterior side elongated, broad, 
sub quadrate; hinge thin, toothless, rectilinear, with a long, 
partly external ligament ; muscular impressions two in each 
valve; palleal impression irregular, not sinuated. — Ohs. This 
genus differs from Mytilus, to which the common muscle belongs, 
in the anterior margin being rounded out beyond the umbo, 
which in Mytilus is terminal. The Lithodomi may be known 
from this genus by their cylindrical form. Fig. 160, M. Tulipa. 

MOLLUSCA. (From Mollis, soft.) The twelfth class of inverte- 
brated animals with univalve shells or none ; divided into the 
following orders: Pteropoda, Gasteropoda, Trachelipoda, Cepha- 
lopoda, Heteropoda, fig. 220 to 488. The term mollusca is 
also used in a general sense to include the classes Conchifera 
and Mollusca of Lamarck, corresponding with the type Malacozoa 
of De Blainville. 

MONEY COWRY. Cyprsea Moneta, which passes current in some 
parts of Africa and the East Indies. 

MONILEA. Sw. A sub-genus of Monodonta. Sw. p. 352. 



MONOPLEUROBRANCHIATA. 191 

MONOCEROS. (Movoq, monos, single; Kepagceras, horn.) Fam. 
Purpurifera, Lam. — Descr. Ovate, thick, covered with a brown 
epidermis ; spire short, consisting of few whorls ; aperture emar- 
ginated anteriorly ; columella rather flat ; outer lip thick, with 
a prominent tooth near the extremity. — Obs. This genus resem 
bles Purpura, in every respect, except in having the tooth 
from which the name is derived. A catalogue of 16 species by 
Mr. Sowerby, sen. is published with figures of 14, in parts 58 to 
67 of the Conchological Illustrations by the author. The species 
belong to the South American coasts of the Pacific Ocean. 

MONOCONDYL^EA. D'Orb. A sub-genus of Uniones, described 
as equivalve, inequilateral, sub-rotund or angulated ; hinge con- 
sisting of a large, obtuse, round cardinal tooth in each valve, with 
no lateral teeth. Monocondylse (Unio) Paraguayana, D'Orb. 
fig. 149. 

MONODONTA. Lam. Odontis, Sow. A genus separated from 
Trochus, Auct. on account of the tooth or notch with which the 
columella abruptly terminates. M. labeo, fig. 366. 

MONOICA. Bl. The second sub-class of the class Paracephalo- 
phora, Bl. divided into the orders Pulmobranchiata, Chismo- 
branchiata, Monopleurobranchiata, in the first section ; and 
Aporobranchiata, Polybranchiata, Cyclobranchiata, Inferobran- 
chiata, and Nucleobranchiata, in the second. 

MONOMYARIA. Lam. (Movog, monos, single; jivov, myon, muscle.) 
The second order of Conchifera, consisting of those bivalve shells 
which have but one principal muscular impression in each valve. 
The Monomyaria are thus divided : First section, containing the 
families Tridacnacea, Mytilacea, Malleacea; second section, con- 
taining the families Pectinides, .Ostracea; third section, con- 
taining the families Rudistes, Brachiopoda. 

MONOPLEUROBRANCHIATA. BL The second order of the 
first section of Paracephalophora Monoica. Bl. The animals are 
described as having the lungs branched, situated at the right side 
of the body and covered more or less completely by the opercu- 
liform mantle, in which there is sometimes enveloped either a flat 



192 MOURETIA. 

or a more or less involute shell, with a large entire aperture. 
They have either rudimentary or auricular tentacula, or none. 
This order, which includes mollusca with haliotoid or patelliform 
shells, is divided into the following families : Fam. 1. Sub- 
aplysiacea ; 2. Aplysiacea ; 3. Patelloidea; 4. Acera. 
MONOPTYGMA. Lea. A genus of small shells resembling Torna- 
tella, but having a strong, oblique fold in the centre of the 
columellar lip. M. Elegans, fig. 344. 
MONOTHALAMIA. (Movoq, monos, single; OaXafiog, thalamos f 
chamber.) The second division of Cephalopoda, Lam. containing 
only one genus, namely Argonauta. 
MONOTHYRA. A term used by Aristotle to designate spiral uni- 
valves. 
MONOTIGMA. Gray. A genus founded on the species represented 
fig. 3/1. It is a turrited shell, but we are unacquainted with the 
characters of the genus. 
MORIO. Montf. Cassidaria, Auct. C. Echinophora, fig. 407. 
MOTHER OF PEARL. This beautiful substance, which is so 
much resorted to for ornamental purposes, constitutes the 
thickened coating of the internal surface of the shell named 
by scientific collectors, Meleagrina Margaritifera, commonly cal- 
led the Pearl Oyster, a young specimen of whieh is figured (164) 
in our plates. The reason why this substance is called mother- 
of-pearl is that the true pearls are produced from its surface. 
They arise principally from accident or disease, and are some- 
times artificially produced by pricking through the outside of 
the shell while the animal is living. The animal is allowed 
to live until it has formed a pearl over the wounded part. 
MOULINSIA. Grateloup. Pupina, Vignard. A genus of small 
land ^shells with enamelled surface and spiral operculum. See 
Pupina. 
MOURETIA. Gray. " Gadin," Adanson. A genus of patelli- 
form shells, described as differing from Siphonaria (the original 
Mouretia of Adanson) in the situation of the siphon, which in 
Mouretia is close to the place where the muscular impression 



MUREX. 193 

is interrupted to leave a space for the head; while in Siphonaria 
it is nearly half way between the anterior and posterior ends of 
the shell. 

MOUTH. The aperture or opening of univalve shells. 

MULINIA. Gray. A genus composed of species of Mactra, 
Auct. described as having the ligament (properly so called) inter- 
nal, and lateral teeth simple. Ex. fig. 82. M. bicolor ; Mactra, 
Auct. 

MULLEMA. Fer. Fam. Ostracea, Lam.— Descr. Irregular, sub- 
quadrate, inequivalve, inequilateral, foliaceous, attached, pearly 
within, green, horny without ; hinge irregular, with a partly 
external ligament, passing to the interior, through a sort of sinus. 
— Obs. This remarkable shell resembles Etheria in general form 
and appearance, but is distinguished by having only one muscular 
impression. It is so rare that, although not very beautiful, a 
specimen has been known to produce £20. at a sale. Fig. 192. 

MULTILOCULAR. Many chambered. 

MULTISPIRAL. (Multus, many, spira, spire.) A term applied to 
a shell when the spire consists of numerous whorls ; or to an 
operculum of numerous volutions. 

MULTIVALVE. (Multus, many ; valva, valve.) Consisting of 
numerous valves. There are three kinds of multivalve shells : 
1st. Those in which the valves are arranged in pairs, and produce 
a flattened figure, as Pedunculated Cirripedes, fig. 34 to 43 ; 
2nd. Those in which the}'' are arranged circularly, as Sessile 
Cirripedes, the valves of which are of two kinds ; the opercular, 
consisting of several valves, which close the aperture, and the 
parietal, consisting of those which surround the body of the 
animal in a circular form, fig. 14 to 33. 3rd. Those in which 
they are arranged in a straight line, as Chiton, fig. 227. 

MUREX. Auct. (A sharp rock.) Fain. Canalifera, Lam. sipho- 
nostoma, Bl.— Descr. Turrited, ventricose, thick, with three or 
more longitudinal, continuous, branched, spinose or fringed 
varices ; spire prominent, acute ; aperture oval, terminating in 
a posterior, partly closed canal, outer lip varicose, inner lip 

o 



194 MUSCULAR IMPRESSIONS. 

smooth, laminar ; operculum horny, concentric, pointed. — Obs. 
This genus contains some of the most exquisitely beautiful shells 
in existence, the richness of their colouring, the ramifications of 
their varices, would render most species the finest possible subject 
for the exercise of the painter's art in still life. The most remark- 
able are the Rosebud Murex, with its pink-tipt fringes, the Venus 
Comb, with its long rows of parallel spines ; the Ducal Murex, 
the Royal Murex, and many others, which are much sought after 
by collectors. Murex may be distinguished from Triton by the 
continuity of the varices, which follow each other in a tortuous 
direction on the spire. The Ranellse have only two rows of varices, 
and have a posterior as well as anterior canal ; while Murices 
have three or more varices, and only one canal. The genus Typhis 
consists of several small species resembling Murex in every respect, 
excepting that of having a tubular opening on the upper part of 
the whorl between each varix. See Typhis. The most beautiful 
Murices are brought from tropical climates. Fig. 395, 396. 

MURICANTHUS. Sw. A sub-genus of Murex, thus described : 
"Varices numerous, foliated; spire short ; margin of the outer 
lip with a prominent tooth near the base ; Radix. Sw. Zool. 111. 
2nd series, pi. 113, Melanomathus. En. Meth. 418. f. 2." Sw. 
p. 296. The latter of the two species quoted, however, does not 
agree with the description, having no prominent tooth on the 
margin of the outer lip. 

MURICATED. (Muricatus.) Having sharp points or prickles. 

MURICIDEA. Sw. A genus of " Muricinse," Sw. thus described, 
"Spire more produced, as long or longer than the body whorl ; 
varices numerous ; no internal channel at the top of the aperture." 
Sw. p. 297, and consisting of the following incongruous species, 
"Lamellosa. Chem. f. 1823, 4. magellanica. En. M. 419. f. 4. 
peruviana. lb. f. 5. senticosa, lb. f. 3. scaber. En. Meth. 419. f. 
6. hexagona. lb. 418. f. 3. erinacea. Mart. f. 1026." Sw. p. 297. 

MUSCULAR IMPRESSIONS are the marks or areas formed on 
the interior surface of shells, by the muscular fibres which 
attach the animals to them. Lamarck has divided his Conchifera 



MYARIA. 195 

into two kinds : 1st. Monomyaria, those which have but one 
adductor muscle, and consequently have but one impression in 
each valve, as the common Oyster, fig. 180 ; 2nd. The Dimy- 
aria, those which have two, and consequently have two impressions 
in each valve. There are other smaller impressions in some shells 
besides the principal. The palleal impression is a mark or scar 
passing near the margin of the shell. See Introduction. 

MYA. Auct. Fam. Myaria, Lam. Pyloridea, Bl. — Descr. Trans- 
verse, oval, thick, gaping at both extremities, rounded anteriorly, 
acuminated posteriorly ; hinge with one large, dilate, compressed 
tooth in one valve, and a suture in the other, containing the 
cartilage ; muscular impressions two, distant, large, irregular ; 
palleal impression with a large sinus. — Obs. Mya may be known 
by the large, prominent, broad tooth in one valve. In Anatina 
there is one in each valve, and, in Lyonsia, accessory pieces. 
Lutraria has cardinal teeth and a ligamentary pit. Few species of 
Mya are known. They belong to the Northern Hemisphere. M. 
truncata, fig. 71. 

MYCETOPODA or MYCETOPUS. D'Orb. Fam. Nayades, Lam, 
— Descr. Shell elongated, soleniform, inequivalve, inequilateral, 
gaping anteriorly; muscular impressions very complex. — Obs. 
These shells are said to terebrate like Fholas. Fig. 151. M. 
solenoides. 

MYARIA. Lam. A family belonging to Lamarck's order Conchi- 
fera Dimyaria. Containing the following genera: 

1. Anatina. Ligament in a spoon-shaped prominence on the 

hinge of each valve, shell thin. Fig. 69. 

2. Mya. Spoon-shaped prominence in one valve ; shell thick. 

Fig. 71. 

3. Anatinella. A spoon-shaped process in both valves. 

Fig. 70. 

4. Lyonsia. An internal bony appendage on the hinge, 

Fig. 491, 492. 

5. Myochama, Flat valve attached, a bony appendage on the 

hinge. Fig. 73. 

o 2 



196 MYRIST1CA. 

6. Cleidoth^rus. Deep valve attached, a bony appendage. 

Fig. 75, 76. 

7. Cumingia. Ligamentary pit in both valves, spoon-shaped. 

Fig. 87. 

MYOCHAMA. Stutch. {Mya and Chama.) Fam. Myaria, Lam. 
— Descr. Inequivalve, irregular, attached, subequilateral; attached 
valve flat, with two marginal, diverging teeth, and one end of a 
little testaceous appendage fixed between them by a horny car- 
tilage ; free valve convex, with umbo incurved and two very 
minute, diverging teeth, between which the other end of the 
testaceous appendage is placed ; external surface of both valves 
conforming to the grooves or undulations of the shell to which the 
specimen is attached ; muscular impressions two in each valve ; 
palleal impressions with a short sinus. — Obs. This new genus, of 
which only one species is known, the M. anomioides from New 
South Wales, differs from Anomia and Anatina in being attached 
by the surface of one of the valves, from which circumstance the 
word Chama is added to its name ; the little testaceous appen- 
dage bringing it near the Myarise. Fig. 73, M. anomioides. 

MYOCONCHA. Sow. {Mya and Concha.) Fam. Cardiacea, 
Lam. — Descr. Oval, equivalve, oblique; umbones terminal; 
ventral margin rounded ; hinge with an external ligament, and 
one oblique, elongated tooth in the left valve ; impression of the 
mantle not sinuated. — Obs. The fossil genus has the general form 
of Mytilus orModiola, but the hinge of the Conchas generally. 

MYOPARA. Lea. {Myoparo, a piratical oar-galley.) Fam. Ar- 
cacea, Lam. A genus founded on a minute fossil bivalve shell, 
somewhat resembling Isocardia in form, but having a series 
of teeth placed on each side of the umbones. M. costatus, 
fig. 135. 

MYRISTICA. Sw. A genus of « Pyrulin^,' ' Sw. thus described : 
" Sub-pyriform ; spire strong, spiny, or tuberculated, nearly as 
long as the base ; umbilicus either partially or entirely concealed ; 
inner lip vitreous, thin ; the outer with an internal and ascending 
canal ; the basal channel wide. Hippocastanea. En. M. 432. f. 4. 



MYTILUS. 197 

lineata, lb. f. 5. melongena. En. Meth. 435. f. 3. nodosa. Chem. 
1564. 5." Sw.p. 307. Ex. P. Melongena, Fig. 

MYRTEA. Turt. Venus spinifera, Auct. Lucina spinifera, Non- 
null. The shells of this genus are described as f« Oval, triangular, 
equivalve, nearly equilateral, closed. Hinge of one valve with 
a single tooth, and lateral one on each side ; of the other valve 
with two teeth, the lateral ones obscure. Ligament external." 
British Channel and Mediterranean. 

MYSCA. Turt. A genus composed of species of Unio, Auct. 
which are distinguished by having "strong, transverse, notched, 
cardinal and long lateral teeth." Unio pictorum. 

MYSIA. Leach. A genus composed of Tellina rotundata, mon- 
tagu and other similar species. 

MYTILACEA. Bl. The fourth family of Lamellibranchiata, Bl. 
The shells are described as regular, equivalve, frequently with a 
thick, horny epidermis. A toothless hinge and a linear ligament. 
This family contains the genera Mytilus and Pinna. 

MYTILACEA. Lam. A family belonging to the first section of 
Conchifera Monomyaria, Lam. described as having the ligament 
partly interior, occupying the greater part of the hinge line, 
which is straight. The shell is rarely foliaceous. The Mytilacese 
cannot easily be confounded with the Malleacese, because the 
former are generally regular and the latter are irregular, and have 
a thick internal coating of pearl, beyond which the external 
coating extends. The genera may be thus distinguished ; 

1. Mytilus. Umbones terminating in a point. Fig. 158. 

2. Dreissina. The same, with a septiform plate. Fig. 159. 

3. Modiola. Anterior margin rounded beyond the umbones. 

Fig. 160. 

4. Pinna. Open at the posterior extremity. Fig. 162. 

5. Lithodomus. Cylindrical, living in holes. Fig. 161. 
MYTILUS. Auct. Fam. Mytilacea. Lam. — Descr. Equivalve, 

cuneiform, oblique, smooth, with umbones terminal, pointed, and 
posterior side broad, rounded ; hinge linear, with a long, partly 
internal ligament ; muscular impressions two in each valve, that 



198 NATICELLA. 

on the posterior side large, irregular ; that on the anterior small ; 
palleal impression irregular. — Obs. The Linnean genus Mytilus 
included the Modiolee, which differ from the Mytili in the rounded 
anterior side ; and the Pinnae, which are large shells, gaping at 
the posterior extremity. M. achatinus, fig. 158. 

NiEARA. Gray. A genus composed of Anatina longirostrum, 
Lam. and other similar species. 

NAIA. Sw. A sub-genus of Castalia, Lam. thus described : 
'*Oval, cardinal teeth beneath the bosses, and deeply sulcated, 
C. corrugata. Lam. En. Meth. 248. f. 8, picta. Sw. En. Meth. 
248. f. 6." Sw. p. 379. 

NANINIA. Gray. A genus composed of the planorbicular species 
of Helix, with large umbilici, and outer lip thin, included in the 
sub-genus Helicella, Fer. Ex. H. citrina, fig. 280. 

NASSA. Lam. A genus of small shells united to Buccinum by 
some authors, but separated by others on account of the little 
tooth-like projection terminating the columella. N. arcularia, 
fig. 423. 

NATICA. Brug. Fam. Neritacea, Lam. Hemicyclostomata, Bl. — 
Bescr. Globose, thick, generally smooth ; spire short, pointed, 
with few volutions ; aperture semilunar, entire ; outer lip thin ; 
columellar lip oblique, nearly straight, callous ; umbilicus with a 
spiral callosity, terminating behind the columella, and sometimes 
filling up the cavity ; operculum shelly in some species, horny in 
others ; epidermis thin, light, semitransparent. — Obs. The 
straight, callous, smooth edge of the columella and the callosity 
serve to distinguish this genus from Nerita, Neritina, Neritopsis 
and Helix. Fig. 327, 328. 

NATICARIA. Sw. A sub-genus of Natica, thus described : "Oval; 
convex above ; umbilicus small, open, placed very near the top of 
the aperture ; inner lip reflected ; small. N. melanostoma, Mart. 
189. f. 1926, 1927. cancellata, Sw. lb. 189. f. 1939. bifasciata, 
Griff. Cuv. l.f. 2." Sw. p. 346. 

NATICELLA. Guild. A sub-genus of Natica, thus described : 
4 ' Operculum horny ; shell globose, but generally depressed; 



NAUTILUS. 199 

umbilicus nearly filled up by a vitreous deposition of the inner 
lip ; spire obtuse. N. aurantia. Mart. 189. f. 1934, 1935." Sw. 
p. 345. 

NAVICELLA. Lam. (A little skip.) Fam. Neritacea, Lam Hemi- 
cyclostomata, Bl. — Descr. Transversely oval, symmetrical, smooth; 
aperture entire, oval ; dorsal surface convex ; outer lip thin ; 
inner lip flat, straight edged ; spread over the front surface of the 
body whorl, and sometimes hiding the apex ; apex incurved ; 
operculum testaceous, flat, sub-quadrate, with a lateral articula- 
tion. — Obs. This well known genus, of which there are several 
species, is named Cimber by Montfort. The shells are brought 
from India, the Isle of France and the Moluccas. Fig. 323, N. 
elliptica. 

NAUTELLIPSITES. Parkinson. A generic name proposed to 
include such species of Nautilus as have been compressed, so as to 
assume an oval instead of a round form. ' The genus Ellipsolites 
of De Montfort consists of species of Ammonites similarly 
deformed. 

NAUTILACEA. Bl. The fifth family of Polythalamacea, Bl, the 
shells of which are described as more or less discoidal, com- 
pressed, symmetrically convolute ; the last whorl much longer 
than the others ; which are entirely hidden beneath it and 
advancing beyond the last but one, so as constantly to form a 
large oval aperture, which is always, however, modified by the 
last whorl. The septa are united in the greater number of 
instances and pierced by one or more (?) siphons. This family 
contains the genera Orbulites, Nautilus, Polystomella and Len- 
ticulina. 

NAUTILACEA. Lam. The sixth family of Polythalamous Cepha- 
lopoda, Lam. containing the genera Discorbites, Siderolites, 
Polystomella, Vorticialis, Nummulites, Nautilus. To these may 
be added Simplegas and Endosiphonites. Fig. 472 to 476. 

NAUTILUS. Auct. {A little boat.) Fam. Nautilacea, Lam. and 
Bl. — Descr. Convolute, discoid, chambered, symmetrical ; spire 
partly or entirely concealed by the last whorl ; aperture modified 



200 NEMATURA. 

by the last whorl, wide, sinuated on the dorsal margin ; interior 
surface pearly ; septa dividing the chambers simple : siphon 
discontinuous. — Obs. The shell named Nautilus by Pliny is the 
Argonauta of modern authors, a thin shell, not chambered. The 
Nautili are known from the Ammonites by the septa being simple, 
not sinuated as in the latter genus, and in general the volutions 
of the spire are not visible. Three or four species are known 
inhabitants of the Pacific Ocean and Australian Ocean. The fossil 
species are found in the tertiary, and also in the secondary strata, 
as low down as the Mountain limestone. N. pompilius, Fron- 
tispiece. 
NAYADES. Lam. A family of the order Conchifera Dimyaria, 
Lam. described as containing fresh-water bivalve shells, with or 
without teeth on the hinge, They are all pearly within, and have 
a thick, rather smooth epidermis without. This family contains 
a great variety of shells, which have been separated into an 
immense number of genera, but which G. B. Sowerby, sen. 
gives very good reasons for uniting under one generic name. 
The most generally received distinctions are as follows : 

1. Castalia. Two cardinal, one lateral, ribbed teeth. This 

genus is removed from the family of Trigonacea. Fig. 140. 

2. Unio. Teeth various. Fig. 142, 145, 149, 148, 147, 

151,141. 

3. Hyria. Trigonal, alated. Fig. 143, 150. 

4. Anodon. No teeth. Fig. 152. 

5. Iridina. Hinge crenated. Fig. 150. 
NECTOPODA. Bl. The first family Nucleobranchiata, Bl. con- 
taining the genera Carinaria and Firola ; the latter is not a shell. 

NEMATOPODA. Bl. The first class of the sub-type Malentozoa, 
Bl. containing all the mollusca with multivalve shells, except 
Chiton, and divided into the families Lepadicea and Balanidea, 
corresponding with Lamarck's sessile and pedunculated Cirripedes, 
and with the Linnsean genus Lepas. 

NEMATURA. Benson. Fam. Turbinacea, Lam.— Descr. Thin, 
nearly oval, somewhat compressed from back to front ; spire 



NERITACEA. 201 

acute, consisting of few rounded whorls ; last whorl large, but 
contracted near the aperture ; aperture small, oblique, rounded 
anteriorly ; peritreme continuous, thin ; operculum spiral, horny, 
with few volutions. — Obs. The distinguishing character of this 
genus is the contraction of the last whorl near the aperture, in 
which respect it is nearly resembled by the shell called Cyclostoma 
lucidum. Two recent and one fossil species, all very minute, are 
described by Sowerby in Loudon's Magazine of Natural History, 
New Series. Fig. 305. 

NERINEA. Defr. Fam. Canalifera, Lam. — Bescr. Turrited, oblong, 
sub-canaliculated, consisting of numerous whorls ; aperture with 
a strong fold on the columella, one on the outer lip, and one on 
the inner lip at the edge of the body whorl.— Obs. This genus is 
only found in a fossil state usually in the Oolitic beds, it is not 
resembled by any other ; the strong, prominent folds on the three 
upper angles of the subquadrate aperture present a singular 
appearance in a section. One species has been named N. Hiero- 
glyphus. We give N. Goodhallii, fig. 374. 

NERITA. Auct. Fam. Neritacea, Lam. Hemicyclostomata, Bl. — 
Bescr. Smooth or ribbed, semiglobose; spire short, sometimes flat, 
consisting of few volutions ; aperture large, semilunar ; outer 
lip thick, entire ; inner lip thickened, dentated at the edge, 
spread over the body whorl, forming a flattened disc ; operculum 
shelly, spiral, with an appendage by which it is locked under the 
sharp edge of the columella. — Obs These marine shells are known 
from Neritina by the thickness of the shell and the want of the 
thick, horny, dark coloured epidermis ; from Natica by the flat 
area produced by the spreading of the thickened columellar lip. 
N. Peloronta, fig. 330. N. polita, fig. 329. 

NERITACEA. Lam. A family of the first order of Trachelipoda, 
Lam. containing the following genera : 

1. Navicella. Apex terminal, not spiral ; inner lip septiform. 

Fig. 323. 

2. Nerita. Columellar lip septiform, edge with distinct teeth ; 

shell thick. Fig. 330. 



202 NICANIA. 

3. Neritina. Shell thin ; columellar lip septiform, edge 

denticulated ; generally a thick, dark coloured epidermis. 
Fig. 324 to 326. 

4. Natica. Having an umbilicus behind the columellar lip, 

with a spiral callosity. Fig. 327, 328. 

5. Neritopsis. Edge of the columellar lip with a deep notch. 

Fig. 331. 

6. Pileolus. Patelliform ; apex central ; columellar lip sep- 

tiform, leaving the aperture small. Fig. 332. 
7. Janthina. Columellar lip linear; aperture angulated. 
Fig. 333. 

NERITINA. Lam. Fam. Neritacea, Lam. — Bescr. Thin, semi- 
globose, obliquely oval, smooth, flattish in front ; spire short, 
sometimes depressed, consisting of few rapidly increasing whorls; 
aperture semicircular; outer lip thin, sharp ; columellar lip broad, 
flat, its inner edge straight, denticulated ; operculum testaceous, 
semicircular, sub-spiral, with an articulating process on the 
inner edge. — Obs. This genus of fresh-water shells differs from 
Nenta in the minuteness of the denticulation of the columella, as 
well as in the characters mentioned in our observations upon the 
latter genus. N. spinosa, (Clithon, Montf.) fig. 325. N. virginea, 
fig. 324. N. perversa, Lam. (Velates, Montf.) fig. 326. All the 
species known up to the present time, with the exception of 
three, are represented in the author's Conchological Illustrations, 
parts 86 , 87, 90, 91, 94 to 100. The catalogue accompanying 
these representations enumerates 59 species. 

NERITOPSIS. Gray. Fam. Neritacea, Lam.— Bescr. Sub-globose, 
thick, cancellated ; spire short, composed of few rapidly increasing 
whorls; aperture transverse, sub-orbicular; outer lip thickened 
within ; columellar lip thick, rather flat, with a large rounded 
notch in the centre of its inner edge. — Obs. This genus most 
nearly resembles Nerita, from which it differs in the peculiar 
notch of the columella. N. granosa, fig. 331. 

NICANIA. Leach. Astarte, Sowerby. The same as CRASsiNAof 
Lamarck. 



NOVACULINA. 203 

NITIDELLA. Sw. Agenusof "Columbellinae,"Sw. thus described: 
" Bucciniform, small, ovate, smooth, glassy; aperture effuse; 
outer lip slightly thickened, faintly inflexed, and generally stria- 
ted internally ; inner lip somewhat flattened above ; base of the 
pillar with one or two slight internal folds, or a single angular pro- 
jection. Columbella nitida, Lam. (fig. 17, C. p. 151.)" Sw. p. 313. 

NOBIA. Leach. Order, Sessile Cirripedes, Lam. This genus 
resembles Pyrgoma, Auct. consisting of a conical paries, supported 
upon a funnel-shaped cavity in the madrepore, but differs in its 
operculum, which consists of two valves, whereas that of Pyrgoma 
has four. N. grandis, fig. 29. 

NODOSARIA. Lam. and Orthocera have been united by 
Sowerby under the name of the first. Fam. Orthocerata, Lam. and 
Bl. — Bescr. Straight, chambered, elongated ; chambers more or 
less ventricose ; septa perforated by a central siphon. — Obs. 
This genus consists only of fossils found in sub-appenine tertiary 
beds. It is placed byDe Blainville in one of his divisions of the 
genus Orthoceras, which is characterized as " species not striated, 
and with chambers very much inflated." N. sequalis, fig. 465. 

NODOSE. Having tubercles or knobs. 

NOGROBS. Montf. A fossil appearing from the figure and de- 
scription to resemble Belemnites. 

NONION. Montf. A genus of microscopic Foraminifera. 

NONIONINA. D'Orb. A genus of microscopic Foraminifera. 

NOTREMA. Rafinesque. A shell described as composed of three 
integral valves, concerning which De Blainville puts the query, 
" ne seroit-ce pas plutot une Balanide mal observee ?" 

NOVACULINA. Benson. {Novacula, a razor.) Fam. Solenacea, 
Lam. — Descr. Equi valve, inequilateral, transversely elongated ; 
external ligament communicating with the interior of the shell by 
an oblique channel; beaks prominent ; hinge line nearly straight, 
with one narrow curved cardinal tooth in one valve, entering 
between two similar teeth in the other ; siphonal scar long ; extre- 
mities of the shell gaping ; epidermis thin, light brown, folding- 
over the edges and connecting the dorsal margins. Hab. Jumna, 
Gooti, and Ganges. Fig. 63. 



204 NUMMULACEA. 

NUCLEOBEANCHIATA. Bl. The fifth order of the second section 
of Paracephalophora Monoica, Bl. the shells of which are described 
as symmetrical, more or less curved, or longitudinally rolled up 
and very thin. This order contains, Fam. 1. Nectopoda, con- 
taining Carinaria ; Fam. 2. Pteropoda, containing Atlanta, 
Spiratella and Argonauta. 

NUCLEUS. (A kernel. ) Anything forming a centre around which 
matter is gathered. The nucleus of shells is the first formed part ; 
the first deposit of shelly matter to which the successive layers 
are added ; the apex of the spiral cone, of which most shells are 
composed. (See Cone.,) The nucleus is formed within the egg 
in oviparous, and within the old shell in viviparous mollusca. It 
is frequently more transparent and light than the remainder of the 
shell, and sometimes falls off ; when this occurs the shell is 
said to be decollated. 

NUCULA. Lam. (A small nut.) Fam. Arcacea, Bl. and Lam. — 
Descr. Equivalve, inequilateral, transverse, covered with an epider- 
mis; hinge linear, with a series of sharp, angulated teeth, arranged 
in a line on each side of the umbones, and a central ligamentary pit; 
muscular impressions two, simple ; palleal impressions not sinu- 
ated. — Obs. The row of teeth on each side of the umbones, and 
the ligamentary pit in the centre of the hinge prevent the pretty 
little shells of this genus from being confounded with any other. 
Thirty-four figures are enumerated in the catalogue by Sowerby, 
sen. which accompanies the Conch ological Illustrations of the 
author. The new species, to the amount of 24, have been figured 
in parts 14 to 16, of the above mentioned work. Recent Nuculse 
are found from the frozen to the torrid zones, and the fossil 
species occur in nearly all the beds from the Pliocene to the 
Carboniferous system. 

NUMMULACEA. Bl. The third family of Cellulacea, Bl, described 
as containing shells or calcareous bodies, which are characterized as 
discoidal, lenticular ; without the slightest traces of whorls to be 
seen externally. The whorls are numerous, internal, and divided 
into a great number of cells, which are separated from each 
other by imperforate septa. This family contains the genera 



OBLiaUE. 205 

Nummulites, Siderolites, Vorticialis, Helicites, Orbiculina, Pla- 
centula. 

NUMMULITES. Lam. (Nummus, money.) Fam. Nautilacea, Lam 
— Descr. Orbicular, convolute, shewing no trace of spire externally; 
interior divided into cells spirally arranged. — 06s. The singular 
fossils composing this genus receive their name from their 
external resemblance to a battered coin. Fig. 4/2. N. lenticulina. 

NUX. Humph. Cyclas, Lam. 

NYMPHACEA. Lam. A family belonging to the order Conchi- 
fera Dimyaria, Lam. Ligament external, placed on a prominent 
fulcrum. This family contains the following genera- 

1. Sangtjinolaria. Rostrated, gaping ; two cardinal teeth in 

each valve, including Soletellina and Lobaria. Fig. 98, 99. 

2. Psammobia. Quadrate; valves closed, including Psam- 

motsea. Fig. 100. 

3. Corbis. Thick, fimbriated ; a cardinal tooth in the centre 

of a pit. Fig. 101. 

4. Grateloupia. A series of small teeth filling a triangular 

area. Fig. 102. 

5. Egeria. One single and one double cardinal tooth. Fig. 

103. 

6. Lucina. Rounded ; anterior muscular impression tongue- 

shaped. Fig. 104. 
7- Tellina. An anterior fold in the ventral margin ; lateral 
teeth. Fig. 105, 106. 

8. Tellinides. No anterior fold ; no lateral teeth. Fig. 107. 

9. Don ax. Margin denticulated; shell wedge-shaped. Fig. 

108. 
10. Capsa. Margin not denticulated, no lateral teeth. Fig. 109. 
OBELISCUS. Humph. Trochus, Lam. 

OBLIQUE, (obliquus. lat.) In a slanting direction. The whorls 
of spiral univalves generally take an oblique direction in reference 
to the imaginary axis of the shell. A bivalve is said to be oblique 
when it slants off from the umbones. An example of this is seen 
in Avicula, fig. 163. 



206 ODOSTOMIA. 

OBSOLETE, (obsoletns, lat.) Worn out, out of use. This 
term is used to express an indistinctness of character, which 
sometimes results from the action of sea- water upon unprotected 
parts of the shell, and sometimes from the deposits of enamel 
formed in age, and covering the early strise, ribs, teeth, &c. 
thereby rendering them less acute. 

OBTUSE, (obtusus, blunt.) The application of this term is not 
peculiar to conchology. It is most frequently used to express 
the character of the spire. Ex. The apex of Megaspira, fig. 294. 

OCEANUS. Montf. (" Come d'ammonvivant," Fr.) Nautilus 
umbilicatus, Auct. 

OCTHOSIA. Ranz. Clitia, Leach. 

OCTOCERA. Bl. The first family of the order Cryptodibranchiata, 
Bl. containing the genus Octopus. A species of which being 
found in the Argonauta, or Paper Sailor, has given rise to the 
long continued controversy as to whether it is really the constructor 
of the shell, or whether it is a mere pirate, and having destroyed 
the true animal of the Argonaut, has possessed itself of the 
habitation. This question is now set at rest. See Argonauta. 

OCTOGONAL. (octogonum.) Having eight angles. For an exam- 
ple, see Dentalium, fig. 2. 

OCTOMERIS. Sow. (ok™, octo, eight ; ^pog, meros, part.) Fam. 
Balanidea, BL Order, Sessile Cirripedes, Lam. — Descr. Eight 
principal valves circularly arranged, forming a compressed cone, 
attached by a jagged base ; aperture enclosed by an operculum, 
consisting of four valves in pairs. — Obs. The only genus of Sessile 
Cirripedes agreeing with this in the number of principal valves is 
Catophragmus, Sow. which is, however, sufficiently distinguished 
by the several rows of smaller valves by which the principals are 
surrounded at the base. 0. angulosus, fig. 24. 

ODONTIS. Sow. Monodonta, Lam. 

ODOSTOMIA. Flem. Descr. " Shell conical ; aperture ovate; 
peristome incomplete, retrally, and furnished with a tooth on the 
pillar." A genus composed of several small species of land 
shells. Turbo plicatus, Spiralis, Unidentatus, &c. Mont. 



ONUSTUS. 207 

OLIVA.' Auct. (An olive.) Fam. Convoluta, Lam. Angyosto- 
mata. Bl. — Descr. Oblong, cylindrical, thick, smooth, shining; 
spire very short, with sutures distinct, aperture elongated, notched 
at both extremities ; outer lip generally thick ; columella thick, 
obliquely striated, terminated by a tumid, oblique, striated varix ; a 
raised band passing round the lower part of the body whorl. — 
Obs. The shells composing this well known genus present a 
great variety of rich markings and brilliant colours. They are 
. marine and tropical. Fossil species are found sparingly in the 
London Clay and Calcaire-grossier. The Ancillarise are dis- 
tinguished from this genus by the sutures of the whorls being 
covered by enamel. 0. maura, fig. 457. 
OLIVELLA. Sw. A genus of " Olivinae," Sw. thus described : 
w Oliviform ; spire (typically) rather produced ; the tip acute ; 
inner lip not thickened ; outer lip straight ; base of the pillar 
curved inwards, and marked by two strong plaits ; upper plaits 
obsolete or wanting ; aperture effused at the base only ; biplicata, 
Tank. Cat. 2332. purpurata. Zool. 111. ii. 58. f. 1. mutabilis. 
Say. eburnea. Zool. 111. ii. 58, f. 2. conoidalis. Lam, No. 57. 
oryza. Lam. No. 62." 
OLYGYRA. Say. Mentioned by Ranz as properly belonging to 

Helicina. H. neritella, Auct. 
OMALAXIS. Desh. Subsequently Bifrontia. Desh. Fig. 354. 
ONISCIA. Sow. (G. B.) Fam. Purpurifera, Lam. Entomosto- 
mata, Bl. — Descr. Oblong, sub-ovate, slightly turbinated, can- 
cellated ; spire short; aperture elongated; terminating anteriorly 
in a very short, recurved canal ; outer lip thickened, denticu- 
lated within ; inner lip spread over a portion of the body whorl, 
granulated.— Obs. The granulated inner lip is the principal 
character by which this genus is distinguished from Cassidaria. 
In Oniscia the canal is not so produced. 0. oniscus, fig. 409. 
ONUSTUS. Humph. A genus proposed by Humphrey and adop- 
ted by Swainson who describes it thus : Si Shell trochiform ; the 
surface irregular, and often covered with extraneous bodies, ce- 
mented and incorporated with the calcareous substance of the 



208 



OPIS. 



shell ; the under part of the body whorl flattened or concave, 
umbilicate. 0. Solaris. Mart. l/3.f. 1/00, 1701. Indicus. lb. 
172. f. 1697. 1698. It is probable, from the above description, 
that Mr. Swainson intended to include Trochus agglutinans of 
authors. (Genus Phorus, Montf.) Fig. 360. 
OPERCULAR. Of, or belonging to, the operculum. A term 
applied to the valves which compose the operculum of multi- 
valve shells, as distinguished from the parietal valves, or those 
which are arranged circularly and form the body of the shell. 
OPERCULINA. D'Orb. A genus of microscopic Foraminifera. 
OPERCULUM. (A cover or lid.) The plate or plates with which 
many molluscous animals enclose the aperture of their shells, 
when retired within them. The operculum is sometimes horny, 
as in Trochus ; testaceous or shelly, as in Turbo. It is spiral 
when from a central or sub-central nucleus, the successive layers 
take a revolving direction, as in Trochus. It is concentric or 
annular when the outside edge of each layer entirely surrounds 
the preceding one. It is unguiculated, when the laminae are 
placed side by side, as in Purpura. The opercula of multivalve 
shells are composed of two or four pieces, which are called the 
opercular valves. The shelly or membranaceous plate with which 
some of the animals enclose the aperture of their shells, during 
the wintry part of the year, for the purpose of protecting them 
while in a torpid state, and which they get rid of by dissolving 
the edges, when preparing to emerge from their temporary re- 
tirement, must not be considered as the operculum, as it does 
not belong to or form part of either the animal or its shell, but 
is produced for the occasion by a secretion of the animal, being 
deposited in a soft state and subsequently hardening. It is 
called the epiphragm, and may easily be distinguished from the 
true operculum by the texture, and by the circumstance of their 
being soldered to the edge of the aperture. The operculum, 
on the contrary, is moveable, and is always composed of a series 
of successive layers, corresponding with the growth of the shell. 
OPIS. Defr. A genus described by De Blainville as consisting 






ORTHIS. 209 

of species of Trigonia which have the umbones sub-spiral, with a 
large, striated tooth on the hinge. Opis cardissoides, Trigonia, 
Lam. Opis similis, Sow. Min. Con. pi. 232. f. 2. 

ORAL. (Os, oris, mouth.) Applied to that part of a shell which 
corresponds with the mouth of the animal, but very seldom used 
in this sense. 

OllBICULA. Lam. (Orbis, an orb.) Fam. Brachiopoda, Lam. 
Palliobranchiata, Bh— Descr. Inequivalve, irregular, sub -orbicular, 
compressed, attached by a fibrous substance passing through a 
fissure near the centre of the lower valve; upper valve patelli- 
form, with the umbo central ; muscular impressions four in each 
valve, semilunar. South America and West Indies. — Obs. Discina, 
Lam. is an Orbicula Crania is known from this genus by 
haying no fissure in the lower valve, but being attached by its 
substance. Hipponyx has only two muscular impressions in 
each valve. 0. lsevis, fig. 201. 

ORBICULAR. (Orbiculus, a little orb.) Of a round or circular 
form. 

ORBICULINA. Lam. A genus of microscopic Foraminifera. 

ORBIS. Lea. A minute fossil, described as " orbicular, with flat 
quadrate whorls and aperture square," in other respects resem- 
bling Solarium. 0. Rotella, fig. 355, 356. 

ORBITINA. Risso. A genus said to be established upon the 



upon 



nuclei of two land shells. 

ORBULITES. Lam. A genus separated from Ammonites on 
account of the last volution covering the spire. This is generally 
considered as characterizing the Nautili, and distinguishing them 
from the Ammonites ; but there are so many gradations that it 
seems impossible to maintain the distinction in this respect. Fig. 
479, O. crassus, fig. 480, 0. discus. 

OREAS. Montf. Part of Cristellaria, Lam. A genus of micro- 
scopic Foraminifera 

ORTHIS. Dalman. {6p0oc, orthos, straight.) Fam. Brachiopoda, 
Lam. One of the generic divisions of Brachiopoda by Dalman, 
thus described: "Hinge rectilinear, with umbones distant ; the 

p 



210 OSTRACEA. 

larger valve with a transverse, basal, smooth area, with a triangular 

pit." 0. basalis, fig. 207. 
ORTHOCERA. Lam. See Nodosaria. 
ORTHOCERATA. Lam. A family of Polythalamous Cephalopoda, 

Lam. containing the following genera: — 

1. Conularia. Conical, externally striated; no siphon. 

Fig. 469. 

2. Amplexus. Cylindrical ; margins of the septa reflected. 

Fig. 463. 

3. Orthoceratites. Straight, gradually conical ;- septa sim- 

ple ; siphon central. Fig. 464. 

4. Nodosaria. Divided externally into lobes. Fig. 465. 

5. Belemnites. Straight, conical; septa simple; siphon 

lateral ; apex solid ; internal cast, or nucleus, pyramidal, 
separable. Fig. 466 to 468. 

6. Conilites. Like Belemnites, but external shell thin at 

the apex. Fig. 470. 

ORTHOCERATA. Bl. The first family of Polythalamacea, Bl. 
containing the genera Belemnites, Conularia, Conilites, Orthoceras 
and Baculites. De Blainville remarks that the genera included in 
this family are all fossils, and known very imperfectly, in conse- 
quence of the greater part of the specimens being only casts. 

ORTHOCERATITES. Auct. Fam. Orthocerata, Lam. and Bl.— 
Descr. Straight, conical, divided into numerous chambers by 
simple septa perforated by a central siphon. 0. annulata, fig. 464. 

OSTEODESMA. Desh. Periploma, Schum. 

OSTRACEA. (Ostracees, Lam.) A family belonging to the second 
section of the order Conchifera Monomyaria, the shells of which 
are described as irregular, foliaceous, sometimes papyraceous, 
with the ligament wholly or partly interior. The principal differ- 
ence between the Ostracea and the Pectinides consists in the 
absence of the auricles and the foliated structure of the shells, 
for, although the Spondylus has ex-foliations or spines upon the 
external surface, the shell itself is compact and firm. This family 
contains the genera Gryphsea, Ostrea, Vulsella, Placuna, Anomia, 
which may be thus distinguished : — 



OSTREA. 211 

1. Pedum. Flat, turned up at the sides, an hiatus for the 

passage of a byssus. A triangular disc on the hinge. Fig. 
179. 

2. Ostrea. Foliaceous, irregular, hinge on a small triangular 

disc. Including Dendostrea, Ostraea, Exogyra, Gryphsea. 
Fig. 180 to 183. 

3. Placuna. Two diverging ribs near the umbones. Fig. 

184. 

4. Placunanomia. The same, but attached by fibres passing 

through a hole in one valve. Fig. 189 to 191. 

5. Anomia. No eostse, attached by a bony substance passing 

through a hole in one valve. Fig. 186 to 188. 

6. Vulsella. Tongue-shaped, a ligamentary pit on the hinge. 

Fig. 185. 

7. Mulleria. Doubtful. Fig. 192. 

OSTRACEA. BL The first family of the order Lamellibranchiata, 
Bl. containing the genera Anomia, Placuna, Harpax, Ostrea 
(including Dendostrea, Sw.) Gryphsea. To these may be added 
Placunanomia, Brod. and Mulleria. 

OSTREA. Auct. (oarptov, ostreon, a bone.) Fam. Ostracea, Lam. 
and Bl. — Descr. Irregular, inequi valve, generally inequilateral, 
foliaceous, attached by part of the lower valve ; hinge sometimes 
slightly crenated ; destitute of teeth ; with the ligament spread 
upon the lower part of a central, triangular area, which is divided 
into three parts ; upper valve much flatter than the lower ; 
muscular impressions one in each valve, large, sub-central, sub- 
orbicular, with one very minute. — Obs. The Linnsean Genus 
Ostrea includes the Pectens and many other genera so different 
from each other that, without any desire to increase the number 
of genera, it was found necessary by subsequent authors to 
separate them. The common Oyster is the type of this genus as 
at present constituted, and is well known to be abundant in 
various parts of the world. Those which depart furthest from 
this type are the Gryphsea, Lam. with a prominent, incurved 
umbo in the lower valve. The Dendostrea, Sw. with margins 

p 2 



212 OVULUM. 

characterized by strongly angulated folds, throws out arms from 
the lower valve, by which they are attached to stems of sea-weed, 
&c. Fig. 180, 0. edulis. Fig. 181, 0. folium. (Dendostrea, 
Sw.) Fig. 182, Grypheea incurva. Fig. 183, Exogyra conica. 

OTIDES. Bl. The first order of Scutibranchiata, Bl. containing 
the genera Haliotis and Ancylus. 

OTION. Leach, (mtlov, a little ear.) Order. Pedunculated Cir- 
ripedes, Lam. — Descr. Body sub-quadrate, supported on a fleshy 
pedicle with a gaping aperture and two posterior auricular tubes; 
valves five, separate, two semilunar, placed at the sides of the 
aperture, two terminal, very small, one dorsal, minute. — Obs. 
Otion differs from Cineras in having two cylindrical posterior 
tubes, and in the extreme minuteness of three out of five of the 
valves. Found on spars floating in the sea, &c. 0. Cuvierii, 
(Lepas aurita, Linn.) Fig. 43, 0. Cuvieri. 

OTIS. Humph. Auricula, Lam. 

OVATE. (Ovatus.) Egg-shaped or oval. 

OVEOLITHES. Montf. A microscopic shell resembling Bulla. 

OVIPAROUS MOLLUSCA. Those which produce their young in 
eggs. Used in distinction from the Viviparous Mollusc a, 
whose young are perfectly formed before they leave the body of 
the parent. 

OUTER LIP. See Labrum. 

OVULUM. Brug. (Ovum, an egg, dim.) Fam. Convoluta, Lam. 
Angyostomata, Bl. — Descr. Ovate or fusiform, smooth, convolute, 
spire covered ; aperture narrow, with a canal at each extremity ; 
outer lip crenulated, inflected ; inner lip smooth, callous towards 
the spiral extremity ; dorsal area wide, sometimes indistinctly 
marked. — Obs. The Ovula were placed by Linnaeus in his genus 
Bulla, from which they are very remote. They differ from Cypreea 
in having the inner lip smooth. We have given representations 
of their different forms as follows: 0. Ovum, fig. 442. 0. ver- 
rucosum, (Calpurnus Montf.) fig. 441. 0. Volva, the weaver's 
shuttle (Radius, Montf.) fig. 442. 0. gibbosum, (Ultimus, 

5 Montf.) fig. 443. 



PAGODELLA. 213 

OXYSTOMATA. Bl. The fifth family of Asiphonibranchiata, Bl. 
This family appears to have been formed for the express purpose 
of providing a place in the system for the genus Janthina, which 
seems to bear so little analogy with other genera of Mollusca, that 
conchological writers have been puzzled to know where to place it. 

PACHYLABRA. Sw. Pachystoma, Guild. A sub-genus of Am- 
pullaria, the outer lip of which is thickened within. Ex. Ampul- 
laria globosa. 

PACHYMYA. Sow. (jraxvc, pachus, thick, and Mya.) Fam. 
Cardiacea ? Lam. — Descr. Obliquely elongated, equivalve, thick, 
sub-bilobed, with beaks near the anterior extremity ; ligament 
partly immersed attached to prominent fulcra. — Obs. This singu- 
lar fossil is shaped like Modiola, but the shell being extremely 
thick, and the ligament attached to a prominent fulcrum, it is 
difficult to know where to place it. Fig. 130, Pachymya Gigas. 

PACHYSTOMA. Guild. (iraxvQ, pachns, thick ; oro/xa, stoma y 
mouth.) A genus composed of such species of Ampullaria, Auct. 
as have the edge of the aperture thickened and grooved within so 
as to form a sort of ledge upon which the operculum rests. Am- 
pullaria globosa and corrugata are examples of this variation. 
The name Pachylabra is given to such species by Swainson, who 
objects to the above name on account of its having been pre- 
viously used to a genus of fishes. Fig. 539. 

PACHYTOMA. Sw. A sub-genus of Helicina, thus described, 
" Aperture entire ; the inner lip very thick ; the spiral whorls 
hardly convex ; P. occidentalis. Zool. J. iii. 15. f. 6-10. viridis, 
Zool. Journ. i. pi. 6. f 7." Sw. p. 337. 

PACLITES. Montf. A genus composed of species of Belemnites, 
Auct. described towards the extremity, with a pore, at the apex, 
and a straight lengthened aperture. Ex. B. ungulatus, Bl. 

PADOLLUS. Montf. A genus composed of species of Haliotis, 
with a strongly marked spiral groove. Ex. H. tricostalis, Lam. 
Fig. 339. 

PAGODELLA. Sw. A sub-genus of Trochus, thus described : 
" Trochiform ; generally thin, and always not pearlaceous ; aper- 
ture and pillar perfectly united and entire; operculum horny. 



214 PALUDOMUS. 

P. major. Mart. 163. f. 1541, 1542. tectum-persicum. lb. f. 
1543, 1544." Sw. p. 351. 

PALLEAL IMPRESSION. {Pallium, a mantle.) The mark or 
groove formed in a bivalve shell by the muscular attachment of 
the mantle, which, being always found near the margin of the 
shell, is sometimes termed the marginal impression. In bivalves 
with two muscular impressions it passes from one to the other. 
If in passing, it takes a bend inwards posteriorly, it is said to be 
sinuated, and that part is called by Mr. Gray, the Siphonal scar. 

PALLIOBRANCHIATA. Bl. The first order of the class Acepha- 
lophora. Bl. The animals of this order are described as more 
or less compressed, included between the two valves of a 
bivalve shell, one inferior, the other superior, joining at the back 
and opening in front. The Palliobranchiata in the system of De 
Blainville correspond with the Brachiopoda in the system of 
Lamarck, and the shells may be known by their being symme- 
trical. This order contains in the first section of symmetrical 
bivalves, Lingula, Terebratula, Thecidium, Strophomena, Plagio- 
stoma, Dianchora and Podopsis : in the second section, Orbicula 
and Crania. 

PALMATED. Flattened like a palm, as the fronds or fringes of 
some Murices. 

PALMINA. Gray. Differing from Otion in having but one 
auricle. 

PALUDINA. Lam, Fam. Peristomata, Lam. Cricostomata, Bl. — 
Descr. Varying in form from oval to globose, in some instances 
oblong, covered with a greenish horny epidermis ; spire acute, 
composed of rounded whorls ; aperture ovate ; peritreme entire, 
slightly modified by the last whorl ; operculum horny, concen- 
tric. Europe, North America, East Indies, China, &c. — Obs. The 
construction of the operculum distinguishes this genus of fresh- 
water shells from Valvata and Cyclostoma. The Paludinse are 
viviparous. Fig. 321. P. Achatina. 

PALUDOMUS. Sw. A genus of the family of " Melanianse," 
Sw. described as differing from Melania in having the spire 
shorter than the aperture. Sw. p. 340. 



PAPYRIDEA. 215 

PANDORA. Brug. Fam. Corbulacea, Lam. Pyloridea, Bl.-— 
Bescr. Thin, inequivalve, pearly within, rounded anteriorly, 
rostrated posteriorly ; right valve flat with a cardinal tooth, 
or short rib, and a slit containing the cartilage with a narrow 
plate on the dorsal edge turned towards the left valve ; left valve 
concave, with a receptacle for the cardinal tooth of the right valve 
and the internal cartilage ; no external ligament. Europe, Ame- 
rica, Ceylon, &c. — Obs. This well known genus is in no danger 
of being confounded with any other shell. Fig. 90. P. rostrata. 

PANOPiEA. Menard. Fam. Solenacea, Lam. Pyloridea, Bl. — 
Bescr. Equivalve, inequilateral, oval, gaping at both extremities; 
hinge with an acute cardinal tooth in each valve, and a large cal- 
losity near the umbones supporting the ligament ; muscular 
impressions two, distant, oval ; palleal impression with a large 
sinus. Britain, North America, Mediterranean, Australia, &c. — 
Obs. This genus resembles Mya in general appearance, but 
differs in having an external ligament and a sharp tooth, in- 
stead of the broad spoon-shaped process in the hinge of the latter 

f genus. Fig. 65. P. Australis. 

PAPER SAILOR. A common name given to the Argonauta. 

PAPILLARY. {Papilla, a teat.) Shaped like a teat. This term 
is applied by conchologists when the apex of the spire of an uni- 
valve shell is rounded like a teat and not spiral up to the extreme 
point ; as the apex of Cymba, fig. 434. 

PAPYRACEOUS. {Papyrus, a kind of paper made of the flags of 
the river Nile in Egypt.) Of a thin, light texture, resembling 
that of paper. An example of this is to be seen in the Argonauta, 
commonly called the " Paper Sailor," fig. 485, and in the Pholas 
papyracea, fig. 56. 

PAPYRIDEA. Sw. A sub-genus of Cardium, thus described ; 
" Shell heart-shaped, or transversely oval ; inequilateral ; the 
anterior side almost always gaping ; representing the Pholidee. P. 
Soleniforme, Wood, Conch, pi. 56. f. 3. — apertum, lb. 56. 
f. 2. — transversum, Sow. Conch, f. 4.— ringens, Wood, pi. 53. 
f. 1, 2. 



216 PATELLA. 

PARACEPH ALOPHORA. Bl. The second class of the type Ma- 
lacozoa, Bl. divided into the sub-classes : P. dioica, P. monoica, 
P. kermaphrodita. 

PARIES. (A wall,) Tke principal part of a multivalve shell, 
forming a circular wall round the body of tke animal, and com- 
posed of one or more valves which are called the parietal 
valves. 

PARIETAL VALVES. The principal valves of multivalve shells 
Burrounding the body like a wall ; as distinguished from the 
opercular valves, or those which compose the operculum. 

PARMACELLA. Cuv. (A little cell.) Fam. Limacinea, Lam. 
and Bl. — Descr, Haliotoid, internal, thin ; spire flat, consisting 
of one or two rapidly increasing whorls ; aperture as large as the 
whole shell, with the dorsal margins inflected. — Obs. This de- 
scription applies to Parmacella of Guvier. The shell figured in 
Sowerby's Genera under that name is Cryptella of Webb. Fig. 
257, P. Olivieri. Fig. 258, P. Pallidum. 

PARMOPHORUS. Bl. A genus composed of Emarginula elon- 
gata, Auct. and other species of a similarly elongated form. Aus- 
tralian. Fig. 242. P. elongatus. 

PARTULA. Fer. Fam. Colimacea, Lam. Auriculacea, Fer. — 
Descr. Conical, smooth ; spire equal to the aperture in length, 
consisting of few whorls ; aperture auriform ; outer lip reflected, 
broad ; inner lip reflected, with a slight prominence on the colu- 
mella. P. austrahs, fig. 302. 

PASITHiEA. Lea. A genus formed of some pyramidal shells, 
described as resembling Melania, but separated from that genus 
on account of being marine fossils. Fig. 317, P. striata. 

PATELLA. Auct. {A dish or platter.) Fam. Phyllidiana, Lam. 
Retifera, BL— -Descr. Symmetrical, compresso-conical, nearly 
regular, oblong or oval ; apex sub-central, inclining towards the 
anterior margin ; aperture oval, forming the base of the shell ; 
internal surface smooth ; with a muscular impression shaped like 
a horse-shoe, with the ends bending forwards, encircling and 
dividing the space all round, except where the interruption occurs 



PECTEN. 21/ 

to receive the head of the animal \ external surface ribbed, 
grooved, striated or banded radiately. On rocks and sea-weeds 
in all climates. — Obs. Patelloida differs from Patella in the con- 
struction of the animal ; Siphonaria, in the lateral siphon ; and 
Ancylus, in the oblique twist of the axis, as well as in the nature 
of the animal. The Patellae are marine. Fig. 229, P. Oculus. 

PATELLIFORM. {Patella, a dish ; forma, shape.) Shaped like 
a dish, or like shells of the genus Patella. 

PATELLOIDA. Quoy and Gaimard. Lottia, Grsy.—Fam. Phyl- 
lidiana, Lam. — Descr. Patelliform, rather flat ; apex obtuse, 
leaning towards the posterior margin ; muscular impression not 
symmetrical, but widest on the right side near the head of the 
animal ; central disc of a variable brown colour. On rocks 
and sea-weeds in all climates.— Obs. The shells of this genus so 
closely resemble Patella that it is almost impossible to make the 
distinction from the shells alone. They are, however, generally 
flatter, and have the apex placed somewhat nearer the posterior 
margin. The animals are very distinct. Fig. 231, P. Antillarum. 

PATELLOIDEA, BL or patelliform shells. The third family of 
the order Monopleurobranchiata, Bl. ; the animals of which are 
described as depressed, flattened, covered by a wide external shell, 
which is patelliform and non-symmetrical. This family contains 
the genera Umbrella and Siphonaria. 

PATROCLES. Montf. A genus of microscopic Foraminifera. 

PATULARIA. Sw. A sub-genus of " Anodontinas," Sw. thus 
described : " Shell nearly equilateral, round or cordate ; no teeth. 
P. ovata, Sw." Ex. Conch, pi. 36. rotundatus, Ib.pl. 137. 

PAVONIA. D'Orb. A genus of microscopic Foraminifera. 

PAXYODON. Schum. Hyria, Lam. 

PECTEN. Brug. {A comb.) Fam. Pectenides, Lam. Subostra- 
cea, Bl. — Descr. Inequivalve, ribbed longitudinally, nearly equi- 
lateral, with a triangular auricle on each side of the umbones ; 
hinge linear, destitute of teeth, having a central pit containing the 
cartilage ; muscular impressions one in each valve, large, sub- 
central. — Obs. This genus of beautiful shells, to which the well 



218 PEDICLE. 

known Scallop belongs, contains numerous species, some of which 
are found in the British Seas. The Hinnites Pusio (P. Pusio of 
some authors) has been separated on account of the irregularity 
of the external surface of one valve. Fig. 171 to 173. 
PECTENIDES. Lam. A family belonging to the second section 
of the order Conchifera Dimyaria, Lam. including the following 
genera. 

1. Pecten. Unattached, including Decatojpecten and Hin- 

nites. Fig. 171, 172, 173. 

2. Lima. Unattached, gaping, Fig. 174. 

3. Plagiostoma. Unattached, with an area between the urn- 

bones. Fig. 176. 
4 Dianchora. Attached by the point of the umbo. Fig. 175. 

5. Spondylus. Attached, irregular, a triangular area in one 

valve, divided by a slit. Fig. 177. 

6. Plicatula. Plicated, a very small area in one valve. Fig. 

178. 

PECTINATED. (Pecten, a comb.) Marked in a regular series of 
ridges. 

PECTUNCULUS. (Pecten, dim.) Fam. Arcacea, Lam. and Bl.— 
Bescr. Equivalve, sub-equilateral, orbicular, thick, covered with 
a velvety epidermis, striated longitudinally ; ventral margin den- 
ticulated within ; hinge semi-circular, with a series of small 
teeth on each side of the umbones, which are separated by a 
small triangular disc in each valve bearing the ligament ; mus- 
cular impressions two in each valve, strongly marked, united by 
an entire palleal impression. — Obs. Linnsean conchologists have 
mixed this genus with Area, from which it is, however, totally 
distinct, not only in the roundness of the general form, but also, 
and principally, in the curve of the hinge line ; in fact the cha- 
racters of this genus are so strongly marked that there is no 
danger of confounding it with any other. It does not contain 
many species ; two or three are British. The fossil species occur 
in London Clay and Calcaire-grossier. Fig. 134, P. pilosus. 

PEDICLE or PEDUNCLE. (Pedunculus, a little foot.) The stem 



PEDUM. 219 

or organ of attachment of the class of shells called in the system 
of Lamarck "Pedunculated Cirripedes," consisting of a fleshy 
tendinous tube, by the lower end of which they are attached to 
sub-marine substances. 

PEDICULARIA, Sw. A genus of " Scutibranchia," thus de- 
scribed: " Shell irregular, sub-patelliform ; a thick, large, obsolete 
apex on one of the longest sides, and an internal callous rim 
within, on one side only ; circumference undulated, irregular. P. 
Sicula, Sw." Sw. p. 357. Sicily. A singular shell of the nature 
of Calyptreea, which is found attached to corals, conforming its 
shape to the irregularity of their surface, and fitting closely. Ex. 
Fig. 513. 

PEDIPES. Adanson. Fam. Auriculacea, Bl. Colimacea, Lam. — 
Descr. Sub-globose, longitudinal, thick, striated ; spire equal to 
the aperture in length ; aperture sub-ovate ; peritreme sharp, 
thickened within, modified by the last whorl ; columella with 
three strong plaits on the inner edge ; outer lip with one fold. 
— Obs. This genus contains but one or two small recent species, 
which in some respects resemble Auricula, from which it is 
known by the thickness of its shell, and its globular form. Fig. 
299, P. Adansoni. Coast of Africa. 

PEDUM. Lam. {A shepherd's crook.) Fam. Pectinides, Lam. 
Sub-ostracea, Bl. — Descr. Irregular, inequivalve, sub-equilateral, 
attached by a byssus passing through a sinus in the lower valve ; 
hinge toothless, with a triangular area in each valve, separating 
the umbones ; ligament contained in a groove running across the 
area ; muscular impressions one in each valve, large, sub-orbicu- 
lar ; both valves flat, narrow at the dorsal, broad at the ventral 
extremities ; lower valve with raised edges overwrapping the 
upper. — Obs. This singular genus, of which only one species is 
known, differs from Ostrea, not only in shape and structure, but 
also in the mode of attachment, which is by means of a byssus 
passing through the lower valve, in Pedum, but by a portion of 
the outer surface of the shell in Ostrea. P. Spondyloideum 
(fig. 179) is the only species at present known. Moluccas. 



220 PENTALEPAS. 

PEDUNCLE. See Pedicle. 

PEDUNCULATED. (Pedunculus, a little foot.) Attached to ex- 
ternal objects by a hollow fleshy tube, called the Peduncle. 

PEDUNCULATED CIRRIPEDES. Lam. An order consisting 
of molluscs which have multivaive shells, supported on a peduncle. 
The genera which it contains are thus distinguished : 

1. Pentelasmis. Five valves. Fig. 34. 

2. Cineras. Five very minute valves distant from each other. 

Fig. 42. 

3. Otion. The same, but the animal has two auricles. Fig. 

43. The genus Palmina, Gray, has but one. 

4. Octolasmis. Shaped like Pentelasmis, but with 7 or 8 

valves. Fig. 41. 

5. Lithotrya. Five valves, peduncle scaly with a plate at 

the base. Fig. 39. 

6. Scalpellum. Shape square, valves 13, peduncle scaly. 

Fig. 35. 

7. Smilium. Same, but the peduncle hairy. Fig. 36. 

8. Ibla. Four valves, one pair long, one pair short, peduncle 

hairy. Fig. 40. 

9. Brismeus. Seven valves, even at the base. Fig. 38. 

10. Pollicipes. Principal valves in pairs, with many smaller 
valves at the base. This genus has been divided into 
Pollicipes, and Capitellum, the latter of which is founded 
upon Pollicipes Mitellus, Auct. Fig. 37 and 37*. 
PELAGUS. Montf. A genus composed of species of Ammonites, 
which have the spire covered by the last whorl, as in Nautilus and 
have an umbilicus. Orbulites. Bl. 
PELLUCID. Transparent. 
PELORUS. Montf. Polystomella, Bl. A genus of microscopic 

Foraminifera. 
PELORONTA. Oken. Nerita Peloronta, Auct. Fig. 330. 
PENEROPLIS. Montf. A genus of microscopic Foraminifera. 
PENICILLUS. Brug. Aspergillum, Auct. 
PENTALEPAS. Bl. Plntelasmis, Auct. 



V E 11 1 O ST R A C U M . 221 

PENTAMERUS. Sow. (Uevte, pente, five ; juepoc, meros, part.) 
Fara. Brachiopoda, Lam. — Descr. Equilateral, inequivalve ; 
one valve divided by a central septum into two parts ; the other 
by two septa, into three parts ; umbones incurved, imperforate. — 
Obs. Dalman remarks upon his genus Gypidia, that it is most 
probably identical with Pen tame rus, Sow. but rejects the name 
for two reasons ; 1st. That it has already been applied to a 
class of insects ; 2nd. He disputes the fact of the shell being 
quinquelocular, i. e. not counting the triangular foramen in the 
hinge of the larger valve as one of the divisions. Fig, 212, 213. 

PENTELASMIS. Leach. (Uevre,pente, five; EXacrjua, elasma, plate.) 
Order. Pedunculated Cirripedes, Lam. — Descr. Compressed, 
conical, composed of five valves ; lower lateral pair sub -trigonal ; 
upper lateral pair elongated, sub-quadrate ; dorsal valve arcuate, 
peduncle elongated, smooth. Found on floating wood in the sea. 
— Obs. This genus is known from all others of the order by the 
number of valves. Pentelasmis is the genus Anatifera of La- 
marck. Lepas anatifer, Linn. Fossil species of this marine 
genus are found in the Calcaire-grossier of Paris, and in other 
similar beds. Fig. 34, P. leevis. 

PENULTIMATE WHORL. The last whorl but one. 

PERA. Leach. A genus composed of Cyclas amnica, and other 

similar species. 
PERDIX. Montf. Dolium Perdix, Auct. 

PERFORATED. (Perforatus.) Bored through, as the apex of 
Fissurella, fig. 245, and Dentalium, fig. 2. 

PERFORATION. (Perforo, to bore, or pierce,) A round opening, 
having the appearance of being bored, as in Haliotis, fig. 338. 
Sometimes the term is applied to an umbilicus which penetrates 
a shell through the axis to the apex, as Eulima splendidula, fig. 348. 

PERIBOLUS. Brug. A genus founded upon young specimens of 
Cyprjsa, with their outer lips not formed. 

PERIOSTRACUM. A name used by Mr. Gray to signify the sub- 
stance which covers the outer surface of many shells, called 
the Epidermis by most conchological writers. <* Drap Marin" is 
the name given to this substance by French Naturalists. 



222 PETRICOLA. 

PERIPLOMA. Schum. Fam. Myarise. A genus thus described : 
" Shell very thin with the left valve more ventricose than the 
right ; hinge toothless, ligament double, the external portion thin, 
the internal part thick, placed upon prominent, sometimes spoon- 
shaped hinge laminae, and supported by a transverse bone ; mus- 
cular impressions two, distant, palleal impression sinuated pos- 
teriorly." Ex. P. inaequivalvis. fig. 72. Genus, Osteodesma, 
Deshayes. 

PERISTOMATA. Lam. A family belonging to the first section of 
the order Trachelipoda, containing the following genera: — 

1 . Ampullaria. Globose or discoidal ; operculum concentric ; 

including Pachystoma^Lanistes, Ceratodes.Fig. 318 to 320. 

2. Paludina. Oval ; operculum concentric. Fig. 321. 

3. Valvata. Globose ; operculum spiral. Fig. 322. 
PERISTOME. The edge of the aperture, including the inner and 

outer lips. 

PERITREME. A term used to express the whole circumference 
of the aperture of a spiral shell. It is said to be notched or 
entire, simple, reflected, round or oval, &c. 

PERLAMATER. Schum. (Mother of Pearl.) Meleagrina 
Margaritifera, Lam. The pearl oyster. 

PERNA. Auct. (" Pernee concharum generis," Plin.) Fam. 
Malleacea, Lam. — Descr. Sub-equivalve, irregular, compressed, 
foliaceous ; hinge straight, linear, composed of a series of trans- 
verse, parallel grooves, containing the cartilage and intermediate 
spaces bearing the ligament ; anterior margin with a sinus for 
the passage of a byssus ; posterior ventral margin oblique, 
attenuated. Obs. This genus is known from Crenatula by the 
straightness, number and regularity of the grooves in the hinge 
and the sinus, for the passage of the byssus. Fig. 166, P, 
Ephippium. Mostly tropical. 

PERSICULA. Schum. A genus formed of Marginella Persicula, 
Auct. and other species having the spire concealed. Fig. 438. 

PERSONA. Montf. (Mask). A genus composed of Triton 
Anus, Auct. and similar species. Fig. 401. 

PETRICOLA. Lam. (Petrus, a stone ; cola, an inhabitant.) Fam. 



PHASIANELLA. 223 

Lithophagidae, Lam. — Descr. Equivalve, inequilateral, transversely 
ovate or oblong, rather irregular, anterior side rounded ; poste- 
rior side more or less attenuated, slightly gaping ; hinge with 
two cardinal teeth in each valve ; muscular impressions two in 
each valve ; palleal impression entire ; ligament external. — Obs. 
The Petricolae are found in holes made by the animals in rocks, 
madrepores, &c. They may be known from Saxicava by the 
regularity of their form and the teeth on the hinge. Fig. 91, 92. 

PETRIFIED FINGERS, CANDLES, SPECTRE CANDLES, &c. 
are vulgar terms by which fossils of the genus Belemnites were 
formerly known. 

PHAKELLOPLEURA. Guild. A genus composed of those 
species of Chiton, Auct. which have bunches of hairs or hyaline 
bristles on each side of each valve on the margin. The Chiton 
fascicularis, found on our own coasts, is a well known example. 
Fig. 506. 

PHARAMUS. Montf. Lenticulina, Bl. A genus of micro- 
scopic Foraminifera. 

PHARETRIUM. Konig. ((f>apETp£<i)i>, pharetrion> a quiver.) — Desc?\ 
A testaceous body composed of two conical sheaths, one within 
the other, perforated at the apex, and joined together near the 
oral margin. P. fragile, fig. 3. In describing this genus, which 
appears to be the same as Entalis of Defrance, Mr. Konig 
expresses the supposition that it may probably belong to the class 
Pteropoda. 

PHASIANELLA. Auct. (Phasianus, a pheasant.) Fam. Tur- 
binacea, Lam.. Ellipsostomata, Bl.— Descr, Smooth, oval, varie- 
gated ; aperture entire, oval ; outer-lip thin ; inner-lip thin, 
spread over a portion of the body whorl ; columella smooth, 
rather thickened towards the base ; operculum horny, spiral 
within ; testaceous, incrassated without. Britain, Mediterra- 
nean, &c. ; the fine large species are Australian. Some fossil 
species are found in the tertiary beds. — Obs. The shells com- 
posing this genus are richly marked with lines and waves of 
various and delicate colours, and if the genus be restricted to 
those species which are smooth, and which have a thick shelly 



224 PHOLAS. 

operculum, we may regard it as well defined ; but there are some 
spirally-grooved species of Turbo, Linn, which, from their oval 
shape, have been considered as belonging to this genus. Such 
species should not, in our opinion, be retained in this genus ; 
they belong to Littorina. P. variegata, fig. 367. 

PHITIA. Gray. Carychium, M tiller. 

PHOLADARIA. Lam. A family of the order Conchifera Dimy- 
aria, Lam. The animals contained in this family live in cavities 
bored by themselves in rocks, wood, &c. They are cylindrical 
in form. Lamarck here places Pholas and Gastroch.ena, the 
last of which belongs more properly to the family of Tubicolaria, 
where we have enumerated it. Pholas has been divided into 
Pholas, fig. 55, Martesia, which has the valves nearly closed ; 
and Pholadidaea, fig. 56, which has the cup -shaped extension. 
The genus Pholadomya, fig. 67, has been added, although of 
doubtful character. The genus Galeomma, fig. 58, 59, has also 
been recently added. 

PHOLADIDiEA. Leach. Pholas papyracea, Auct. Remarkable 
for the cup-shaped process at the posterior extremity. Fig. 56. 

PHOLADOMYA. Sow. (Pholas and My a.) Fam. Pholadaria, 
Lam. — Descr. Thin, rather hyaline, equivalve, inequilateral, 
ventricose, posteriorly gaping, elongated, anteriorly short, round- 
ing ; ventral margin rather gaping ; hinge with an elongated 
pit, and lateral plate in each valve ; ligament external, short, 
muscular impressions two in each valve, rather indistinct ; palleal 
impression with a large sinus. — Obs. The only recent species of 
this genus is from the island of Tortola. Several fossil species 
occur in rocks of the Oolitic series. Fig. 57, P. Candida. 

PHOLAS. Auct. (®(x)\eu), pholeo, to lie hid in a cavity.) Fam. 
Pholadaria, Lam. Adesmacea, Bl. —Descr. Transverse, oblong, 
equivalve, inequilateral, imbricated, gaping on both sides, the 
anterior hiatus being generally the largest, although sometimes 
nearly closed, with the dorsal margin surmounted with one or 
more laminar accessary valves ; hinge callous, reflected, with a 
long curved tooth protruding from beneath the umbones in each 
valve. — Obs. This genus of marine shells, dwelling in holes 



PHYLLONOTUS. 225 

formed in rocks, wood, &c. is easily distinguished from any other 
nearly allied genus by the curved, prominent, rib-like teeth. 
Fig. 55, P. Dactylus ; 56. P. papyracea. 

PHOLEOBIUS. Leach. Part of the genus Saxicava, Auct. 

PHONEMUS. Montf. A genus of microscopic Foraminifera. 

PHORUS. Montf. Trochus agglutinans, Auct. Remarkable for 
the adhesion of little pebbles, dead shells, &c. to the outer edge 
of the whorls, which are taken up in the course of the growth of 
the shell. From this circumstance they are called " Collectors, 
Carriers, &c." Fig. 360. Recent species are brought from the 
East and "West Indies ; fossil species are found in the Tertiary 
beds. 

PHOS. Montf. Fam. Purpurifera? Lam. — Descr. Turrited, thick, 
cancellated, varicose ; spire pointed, generally longer than the 
aperture ; aperture rounded or oval ; outer lip having internal 
ridges, with a sinus near the anterior termination ; columella 
with an oblique fold ; canal short, forming externally a raised 
varix. — Obs. The raised external surface of the canal, brings this 
genus near to Buccinum, while, in general appearance, most of 
the species more nearly resemble Murex. They have, however, 
no true varices on the whorls, but merely raised bars. Fig. 416, 
P. senticosus. 

PHYLLIDIANA. Lam. A family belonging to the first section 
of the order Gasteropoda, Lam. The genera belonging to this 
family may be distinguished as follows : 

1. Chiton. Composed of eight valves; valves contingent. 

Fig. 227. 

2. Chitonellus. The same, with the valves distant. Fig. 228. 

3. Patella. Conical, symmetrical. Fig. 229, 230. 

4. Patelloida Differing from Patella in the animal. Fig. 

231. 

5. Siphonaria. With a siphon on one side. Fig. 231*. 

6. Sctjtella, Siphon close to the side of the head. Fig. 

510, 511. 
PHYLLONOTUS. Sw. A sub-genus of Murex, thus described : 
' ' Canal moderate; varices foliated, laciniated, compressed, or 



226 PINNA. 

resembling leaves; inflatus. Mart. 102. fig. 980, eury stoma. 
Zool. 111. ii. 100. imperialis. lb. pi. 109." Sw. p. 296. 

PHYSA. Drap. A genus formed for reversed species of Limnsea, 
Auct. Fig. 310, P. castanea. 

PHYSETER. Humph. Solarium, Lam. 

PILEOLUS. Cookson. (A little cap.) Fam. Neritacea, Lam. — 
Descr. Patelliform, with the apex sub -central, straight. In the 
lower disc, or under surface, the centre of which is rather raised 
or cushion-shaped, is placed the lateral, narrow, semilunar aper- 
ture, with the outer lip marginated and the inner lip crenulated. 
— Obs. This interesting genus is known only in a fossil state. 
Two species are found in the upper layer of Oolite, above the 
Bradford clay. The spire, although internal, connects this genus 
in some degree with Neritina. Still there is no danger of con- 
founding them. Fig. 332, P. plicatus. 

PILEOPSIS. Lam. Capulus, Montf. 

PILLAR. The usual English name for the column which forms the 
axis of spiral shells, around which the whorls revolve. See 
Columella. 

PINNA. Auct. {The fin of a fish.) Fam. Mytilacea, Lam.— 
Descr. Equivalve, inequilateral, oblique, wedge-shaped, thin, 
horny ; umbones terminal ; hinge rectilinear, without teeth ; 
anterior margin sinuated, to admit the passage of a byssus ; 
posterior margin truncated, gaping ; muscular impressions two 
in each valve ; posterior large, sub-central; anterior small, ter- 
minal, sometimes double. — Obs. The beautiful large shells of 
which this genus is composed, are possessed of a large, flowing, 
silky byssus, of which gloves and hose have been manufactured. 
They have received their name from their resemblance to the 
pectoral fins of some fishes. Some species attain very large 
dimensions, and measure two feet in length. A very improbable 
story is told with regard to animals of this genus, namely that a 
certain small species of crab is in the habit of taking refuge from 
its enemies in the shell of the Pinna, into which it is received 
with great hospitality and kindness by the " blind slug" which in- 
habits it. In return for which kindness, he occasionally goes abroad 



PLACUNA. 227 

to procure food for both. On his return he knocks at the shell, 
which is opened to receive him, and they share the supplies 
together in convivial security ! Some species are smooth, although 
the greater number are imbricated or crisped outside. P. saccata, 
fig. 162. 

PINNATED. (From Pinna, a fin.) When a part of a shell is spread 
out and smooth, as in Rostellaria columbaria, fig. 403, it is said 
to be alated, or winged, but when the part which is spread is 
radiated or ribbed, like the fin of a fish, it is pinnated, as in Mu- 
rex pinnatus, and Murex tripterus. (Conch. Illustr.) 

PIRENA. Lam. A genus of fresh-water shells, rejected by De 
Ferussac and other authors, who place Lamarck's two first species 
with Melanopsis, and his two last with Melania. Fig. 316, P. 
terebralis. 

PISIDIUM. Leach. A genus of river shells separated from Cyclas 
principally on account of a difference in the animal. The species 
of Pisidium, however, are less equilateral than the Cyclades, and 
the posterior or ligamentary side of the latter is the longer, while 
that of the former is the shorter. Fig. 112. 

PISIFORM. (Pisum, a pea ; forma, shape.) Shaped like a pea or 
small globular body. 

PISUM. Megerle. (A pea.) Pisidium, Leach. 

PITHOHELIX. Sw. A sub-genus of " Geotrochus, ,, Sw. Sw. 
p. 332. 

PITONELLUS. Montf. Rotella, Auct. 

PLACENTA. Schum. Placuna, Auct. 

PLACENTULA. Schum. A genus of microscopic Foraminifera. 

PLACUNA. Brug. (ir\a.KovQ,placos, a cake.) Fam. Ostracea, Lam. 
and Bl. — Descr. Compressed, thin, equivalve, nearly equilateral, 
planorbicular, fibrous, foliaceous ; hinge flat, with two diverging 
ribs in one valve, and two corresponding grooves in the other, con- 
taining the cartilage ; muscular impressions one, large, circular, 
central, and one or two smaller in each valve. — Obs. The two best 
known species of this well defined genus are the P. Placenta, 
commonly called the Chinese Window Shell, and the P. Sella, 

Q 2 



228 



PLANAXIS. 



called the Saddle Oyster, from the anterior margin being turned 
up so as to resemble a saddle. The genus may be known from all 
others by the diverging costaon the hinge. Placunanomia is the 
only genus resembling it in this respect, but this is easily dis- 
tinguished by a perforation through the shell. Fig. 184, P. 
Placuna. These shells are used in China to glaze windows. 

PLACUNANOMIA. (Sw. Placuna and Anomia.) Fam. Ostracea, 
Lam. and Bl. — Descr. Thin, foliaceous, compressed, sub-equi- 
valve, sub -equilateral, irregular, flat near the umbones, plicated 
towards the margins, attached by a bony substance passing through 
a fissure in the lower valve ; hinge flat, with two diverging ribs 
in one valve, corresponding with two diverging grooves, con- 
taining the cartilage, in the other ; muscular impressions one in 
each valve, central, sub-orbicular. — Obs. The specimens from 
which Mr. Broderip described this singular genus, were brought 
by Mr. Cuming from the gulf of Dulce in Costa Rico. Another 
species is from one of the Philippine Islands. They partake of 
the characters of several genera, having the hinge of Placuna, and 
being attached by a process passing through the lower valve, like 
Anomia. P. Cumingii, fig. 189. 

PLAGIOSTOMA. Sow. Min. Con. (TrXayiog, plagios, oblique; 
(rro/ja, stoma, mouth.) Fam. Pectenides, Lam. Palliobranchiata, 
Bl. — Descr. Sub-equi valve, inequilateral, oblique, auriculated on 
each side of the umbones, radiately striated ; hinge straight in 
one valve, with a triangular notch in the other. — Obs. This 
genus, one species of which is spinous, and another smooth, is 
only known in a fossil state. It is found in the Lias and chalk. 
Fig. 176, P. spinosum. 

PLAIT or FOLD. A term applied to the prominences on the colu- 
mellar lip of some univalve shells, particularly in the sub-family of 
Volutidse. Ex. Voluta, fig. 433; Cymba,434; and Melo, fig. 435. 

PLANAKIA. Brown. A minute fossil resembling Planorbis in 
appearance, but differing in being a marine shell, and having a 
reflected outer lip. P. nitens, fig. 312, from Lea's Contributions 
to Geology. 

PLANAXIS. Lam. {Plana, flat; and axis.) Fam. Turbinacea, 



PLANULACEA. 229 

Lain. Entomostomata, Bl. — Descr. Sub-ovate, pyramidal, solid ; 
spire measuring J- or ^ of the axis, consisting of few whorls ; co- 
lumella contiguous to the axis, flat, truncated, and separated from 
the outer lip by a short canal ; outer lip thickened and denticu- 
lated within ; operculum horny, thin, with a terminal nucleus, — 
Obs. This is a genus of small marine shells found in the West 
Indies, &c. Fig. 365, P. sulcata. 

PLANE. {Planus.) Flat, planed, as the columellar lip of Pur- 
pura, fig. 414. 

PLANORBICULAR. {Planus, flat ; orbis, an orb.) Flat and cir- 
cular, as Ammonites, fig. 478. 

PLANORBIS. Miill. {Planus, flat; orbis, an orb.) Fam. Lymnacea, 
Lam. and Bl. — Descr. Thin, horny, convolute, planorbicular, 
nearly symmetrical ; spire compressed, concave, consisting of nu- 
merous gradually increasing whorls, which are visible on both sides ; 
aperture transversely oval, or nearly round; peritreme entire; 
outer lip thin ; inner lip distinct, spread over a part of the body 
whorl. — Obs. This is a genus of shells abounding in all climates in 
ditches and stagnant pools, not liable to be confounded with any 
other, excepting the discoidal species of Ampullaria, which may 
be distinguished by the aperture being broadest in the opposite 
direction. It is further to be remarked that the discoidal Ampul- 
larise are dextral shells, and the Pianorbes are sinistral or reversed ; 
and although the latter are sometimes so flat and orbicular that 
it is difficult to know which is the spiral side, it may nevertheless 
always be ascertained by a careful examination. Fossil species are 
found in the fresh-water strata of the Isle of Wight, and the 
neighbourhood of Paris. Fig. 311, P. corneus. 

PLANORBULINA. D'Orb. A genus of microscopic Foraminifera. 

PLANULACEA. Bl. The second family of Cellulacea, Bl. The 
microscopic Foraminifera contained in this family are described 
as very much depressed, not spiral, chambered, cellular, and 
having the septa indicated by grooves on the external surface of 
the shell, which increase in length from the apex to the base : some 
of the small cellular cavities are to be seen on the margins. This 
family contains the genera Renulina and Peneroplis, 



230 PLEUROBRANCHUS. 

PLANULARIA. Defr. Peneroplis, Montf. A genus of micro- 
scopic Foraminifera. 

PLANULINA. D'Orb. A genus of microscopic Foraminifera. 

PLANULITES. Lam. Discorbites of the same author. A genus 
of microscopic Foraminifera. 

PLATIRIS. Lea. (ttWi^, platus, wide ; ipig, iris.) A genus 
including several species of Nayades, referred to Iridina, Lam. 
The genus Platiris is divided into two sub-genera. Iridina, species 
which have crenulated margins ; I. Ovata, I. exotica, Spatha, Lea; 
those with smooth or very slightly crenulated hinges, S. rubeus, 
S. Solenoides, Mycetopus, D'Orb. Fig. 151. 

PLATYLEPAS. {iv\aTVQ,platus, wide ; Xekclq, Upas, rock.) Order. 
Sessile Cirripedes, Lam. Fam. Balanidea, Bl. — Descr. Conical, 
depressed, consisting of six valves, each divided internally by an 
angular plate jutting from the centre (like the buttress of a wall ) ; 
operculum consisting of four valves in pairs. — Obs. This genus 
differs from Balanus, Coronula, &c. in the internal structure of the 
valves. De Blainville's description of Chthalamus partly agrees 
with this. Fig. 19. 

PLECTOPHORUS. Fer. (tzXtikt^ov, plectron, spur ; Qopiu), phoreo, 
to carry.) A genus consisting of small testaceous appendages 
fixed on the posterior extremity of a species of slug. P. corninus, 
fig. 260. 

PLEIODON. Conrad. Iridina, Lam. Fam. Nayades, Lam. 

PLEKOCHEILUS. Guild. Auricula Caprella, Lam. Carychium 
undulatum, Leach. (Caprella, Nonnull.) This proposed genus 
is described as scarcely umbilical, dextral, oval, spiral ; with the 
spire elevated, obtuse ; the two last whorls very large, ventricose ; 
aperture entire, elongated ; columella with a single plait ; the 
plait concave, inflected. Fig. 522, 523. 

PLEUROBRANCHUS. Cuv. (IRe^a, pleura, the side ; Branchia, 
gills.) Fam. Semiphyllidiana, Lam. Subaplysiacea, Bl. — Descr. 
Internal, thin, haliotoid, slightly convex towards the spiral apex ; 
aperture entire. — Obs, This is a very light shell, delicately coloured, 
resembling Aplysia, but differing in the integrity of the margin. 
Fig. 232, P. membranaceus. 



PLEUROTOMA. 231 

PLEUROCERUS. Rafinesque. A genus very imperfectly described in 
the "Journal de Physique'' as "oval, or pyramidal; aperture 
oblong ; outer lip thin; inner lip truncated at the columella, which 
is smooth and tortuous, not umbilicated. Operculum horny or 
membranaceous." De Blainville, in giving this description, re- 
marks that he has neither seen the animal nor the shell of this 
genus, which he imagines to have been formed from the " Paludine 
Coupee de M. Say." 

PLEURORYNCHUS. Phillips, (ttkevpa, pleura, the side ; pvy X oQ, 
rynchus, a beak.) A genus founded upon a very singular species 
of Cardium, distinguished by the short anterior side, and the 
elongation of the hinge line into auricular processes, which are 
truncated at the extremities. C. Hibernicum from the Black Rock 
near Dublin, which is vulgarly called Asses-hoof, and C. elonga- 
tum (Sow. Min. Con. vol. 1. 82.), form part of this genus. 

PLEUROTOMA. Lam. Fam. Canalifera,Lam. Siphonostomata, Bl. — 
Descr. Fusiform, thick, in general ribbed or striated transversely ; 
aperture oval, terminating anteriorly in an elongated canal ; outer 
lip thin, with a fissure near its spiral extremity; columella smooth, 
nearly straight. Found principally in tropical climates. — Obs. 
This genus, which nearly resembles Fusus in other respects, may be 
known by the notch in the outer lip. The species differ in the length 
of the canal. Swainson has designated this genus a family, thus 
divided into genera : Brachytoma, in the description of which he 
says that the spire and aperture are of equal length, including the 
species strombiformis : Pleurotoma, in which the channel is so 
much lengthened, as to be little shorter than the spire : Clava- 
tula, having the long narrow slit of Pleurotoma, but with a very 
short canal : Clavicantha, having the canal equally short, but the 
sinus or notch, instead of being linear and long, is short and 
wide ; the surface is rough, and the whorls either coronated with 
prickles, or with compressed nodules resembling spines : Tomella, 
which has the spire and canal fusiform, but the spire of very few 
whorls, and the inner lip considerably thickened within where it 
joins the outer lip. Fig. 379, 389, P. marmorata ; 381, P. 
Strombiformis, (Clavatula, Sw.) 



232 PLICATULA. 

PLEUROTOMARIA. Defr. Fam. Turbinacea, Lam.— Descr. 
Turbinated, spiral ; aperture sub- quadrate, with rounded angles ; 
outer lip with a deep slit near its union with the spire. — Obs. 
This genus, which is only known in a fossil state, abounds in in- 
ferior Oolite, Oxford clay, and casts are found in a limestone 
bed in Norway. The Scissurellae differ in being very minute 
shells, and are not so trochiform as the species of Pleurotomaria, 
P. reticulata, fig. 34 1 . 

PLICACEA. Lam. A family of the order Trachelipoda, Lam. 
containing the following genera : 

1. Pyramidella. Pyramidal, with numerous whorls. Fig. 

342. 

2. Tornatella. Cylindrical, with few whorls. Fig. 343, 

344. 

3. Ringicula. Margin reflected. Fig. 540, 541. 
PLICADOMUS. Sw. A sub-genus of Pupa, thus described : 

u spire moderate, regular and thick, but gradually conic; the 
tip obtuse ; aperture perpendicular ; inner lip wanting ; outer 
lip semicircular ; the margin dilated and reflected. P. sulcata, 
Chem. 135, f. 1231, 1232." Sw. p. 332. 

PLICATED. {Plicatus, folded.) Applied to spiral plaits on the 
columella of some shells. Ex. Voluta, fig. 433. Also to the 
angular bendings in the margins of some bivalve shells. Ex. 
Dendostrea, fig. 181. 

PLICATULA. Lam. (Plicatus, folded.) Fam. Pectenides, Lam. 
Sub-ostracea, Bl. — Descr. Irregular, sub -e qui valve, sub-equi- 
lateral, attached by a small part of the surface of one valve, 
strongly plicated ; umbones separated by a small, external liga- 
mentary area ; hinge with two cardinal teeth in each valve, two 
approximate in one valve, received between two distant in the 
other ; cartilage placed between the cardinal teeth ; muscular 
impressions one in each valve. — Obs. The cardinal teeth resem- 
bling those of Spondylus, distinguish this genus from others of 
the Lamarckian family Pectenides. Very few species are yet 
known, they are brought from the East and West Indies and the 



POLYGONUM. 



233 



Philippine Islands. Fossil species are found in several of the 
supra-cretaceous beds. Fig. 178, P. gibbosa. 

PNEUMOBRANCHIA. Lam. The second section of the order Gaste- 
ropoda, Lam. containing the family Limacinea, fig. 256 to 263. 

PODOPS1S. Lam. This genus appears to have been described 
from specimens of a species of Spondylus, with the triangular 
disc broken out, so as to present a similarly shaped foramen, 
which was supposed to afford a passage for a large byssus. 

POLINICES. Montf. A genus composed of Natica Mammilla, 
and other similar species, with mammillated spires, and the 
umbilicus filled with enamel. Fig. 327. 

POLLIA. Gray. Tritonidea, Sw. The name given by Gray 
was pre-occupied by a genus of Lepidopterous Insects. 

POLLICIPES. Leach. (Pollex, a thumb's breadth; pes, a foot.) 
Order. Pedunculated Cirripedes, Lam. — Descr. Conical, com- 
pressed, consisting of numerous valves, mostly in pairs, three or 
four pairs forming the principal part of the shell, and surrounded 
at the base by two or three rows of smaller valves, supported on 
a scaly, short pedicle.— Ohs. This description will be found to 
exclude Scalpellum, and Smilium, the valves of which are more 
equal. The P. Mitellus, Auct. (fig. 37*), has been separated as a 
genus under the name of Mitellus by some authors, and it is cer- 
tainly very different from P. polymerus, fig. 37, and P. cornucopia. 

POLLONTES. Montf. Miliola, Bl. A genus of microscopic 
Foraminifera. 

POLYBRANCHIATA. Bl. (IIoXvq, polus, many ; , branchice, gills.) 
The fifth family of the order Lamellibranchiata, Bl. containing 
the genera Area, Pectunculus and Nucula, which have a series of 
small teeth on the hinge. 

POLYDONTES. Montf. ( UoXvq, polus, many ; oSoq, odos, tooth.) 
A species of Helix, shaped like Carocolla, and haying a 
number of teeth in the aperture. 

POLYGONAL . Many-sided. 

POLYGONUM. Schum. (YLoXvc, polus, many ; yoma, gonia, an 
angle.) A genus composed of species of Turbinella, Auct. 



234 POI.YTROPA. 

which have large continuous costse, so as to present the appear- 
ance of many-sided shells. T. polygonus, fig. 383. This generic 
name may be used to include all those species of Turbinella, 
Auct. which have very small folds on the columella. 

POLYGYRA. Say. A genus of Heliciform shells, characterized 
by the large number of close set whorls, constituting the spire. 
Ex. P. Septemvolvus, fig. 275, 276. 

POLYLEPAS. Bl. (IIoXvc, polus, many; \e7rag t lepas, Linn.) 

SCALPELLUM, Auct. 

POLYMORPHINA. D'Orb. A genus of microscopic Forami- 
nifera, 

POLYPHEMUS. Montf. A genus composed of species of Acha- 
tina, Auct which have elongated apertures, short spires, and 
an undulation in the outer lip. P. Glans, fig. 288. 

POLYPLAXIPHORA. Bl. The second class of the sub-type 
Malentozoa, Bl. containing the genus Chiton. 

POLYSTOMELLA. Lam. A genus of microscopic Foraminifera. 

POLYTHALAMACEA. Bl. (IloXve, polus, many ; OaXa/ioe, tha- 
lamos, chambers.) The third order of Cephalophora, Bl. the 
shells of which are described as straight, more or less symmetri- 
cally convolute, divided into several chambers. The septa are 
sometimes, but not always, pierced by one or more siphons. 
This order is divided into the families, Orthocerata, Lituacea, 
Cristacea, Ammonacea, Nautilacea, Turbinacea, Turriculacea, all 
of which contain genera of chambered shells. De Blainville 
arranges these families according to the degree in which the 
spires revolve. The first being straight, as the Orthocerata, and 
the last being so closely coiled up, that the last whorl covers the 
rest, as in the Nautilacea. 

POLYTHALAMIA. Lam. The first division of the order Cepha- 
lopoda, Lam. containing the following families of chambered 
shells, viz. Orthocerata, Lituacea, Cristacea, Sphserulacea, Radio- 
lata, Nautilacea, Ammonacea. Fig. 463 to 484. 

POLYTROPA. Sw. A genus of " Scolyminee," Sw. thus described: 
" Bucciniform ; but the base narrow, and ending in a straight 



POSTERIOR. 235 

and contracted, but rather short, channel ; spire longer, or as 
long as the aperture ; exterior folliculated, or tuberculated ; inner 
lip flattened, as in Purpura ; basal notch small, oblique ; no 
internal channel; crispata. En. Meth. 419, f. 2. Cheni. 187, f. 
1802. Capilla, Pennant, pi. 72, f. 89, imbricata. Mart. 122. f. 
1124. ? rugosa. Chem. f. 1473-4." Sw. p. 305. 

POLYXENES. Montf. A genus of microscopic Foraminifera. 

POMATIA. Gesner. (Gray, Syn. B. M. p. 133.) A genus of the 
family of (i Cyclostomidse," described as having ** an elongated 
shell with reflexed lips, and a horny spiral operculum.' ' Also a 
sub-genus of Snails, containing Helix pomatia, Auct. (Gray's 
Turton, p. 135.) 

PORNUS. Humph. Ampullaria, Lam. 

PORCELLANA. Adanson. Marginella, Auct. 

PORODRAGUS. Montf. A genus composed of species of Belem- 
nites, placed by De Blainville in the section characterized as 
swelled near the apex, and straightened towards the base. 

POSIDONIA. Brong. A genus formed on the cast of a bivalve 
shell, common on schists from Dillemberg. 

POSTERIOR. (After, behind.) The posterior or hinder part of a 
bivalve shell, is that in which the siphonal tube of the animal is 
placed. It is known in the shell, by the direction of the curve 
in the umbones, which is from the posterior towards the anterior ; 
also by the ligament, which is always placed on the posterior part 
of the hinge, when it exists only on one side of the umbones ; 
and by the sinus (when there is one) in the palleal impression, 
which is always near the posterior muscular impression. In 
some shells, however, it is very difficult for a learner to trace 
these marks ; such bivalves, for instance, as have the ligament 
spread out on both sides of the umbones ; such as are nearly 
symmetrical, and have the umbones consequently straight, and a 
single muscular impression near the centre of the valve. The 
Brachiopodous bivalves have a different position, with relation to 
the animal, from the other bivalves, so that the hinge line is the 
posterior extremity, and the part where the valves open, is the 



236 POTAMOPHILA. 

anterior. The posterior extremity of the aperture of a spiral 
univalve shell, is that nearest to the spire. In patelliform shells 
the anterior and posterior extremities are distinguished by the 
muscular impression, which is annular, enclosing a central disc 
in the inner surface of the shell, excepting where it is interrupted 
by the place where the head of the animal lies, which of course 
is anterior. The posterior is marked p. in fig. 119, and 387. 
See Anterior. 

POSTERO-BASAL MARGIN of a bivalve shell is the posterior side 
of the margin opposite the hinge. 

POSTERO-DORSAL MARGIN is the posterior side of the hinge. 

POTAMIS or POTAMIDES. Brong. A genus of fresh-water 
shells resembling Cerithium in the characters of the aperture, 
but which may be known from that genus by the thick, horny 
epidermis with which they are coated. P. muricata, fig. 377. 
(Cerithium, Sow.) We think that these shells should be placed 
near Melania. 

POTAMOMYA. A genus of shells resembling Corbula, in every 
respect except that of being inhabitants of fresh-water. Fig. 
498, 499, represents one of these fresh-water Corbulse. 

POTAMOPHILA. Sow. (UoTajjLiQ, potamis, river ; $i\iog, philios, 
choice.) " Conques fluviatiles," Lam. — Descr: Thick, equivalve, 
inequilateral, trigonal, covered with a greenish brown, smooth, 
horny epidermis ; hinge thickened, broad, with one central, 
notched cardinal tooth in one valve, and two in the other, with 
indistinct lateral teeth ; ligament large, supported on prominent 
fulcra ; muscular impressions two in each valve, sub-orbicular. — 
Obs. The name given to this shell refers to its place of abode, 
being found in rivers. It is the Venus sub-viridis of some 
authors, although being a fresh-water shell, and having an 
incrassated hinge, and a smooth, thick epidermis, it is most 
distinct from that genus. It is described by Bowdich under t e 
name Megadesma, on account of its large ligament, and by 
Lamarck under that of Galathsea, a name previously used by him 
for a genus of Crustacea. P. radiata, fig. 115. Megadesma 



PSAMMOBIA. 



237 



appears to be the preferable name, since it has the right of 
priority over Potamophila. It is found in Africa. 

PRIAMUS. A genus composed of Achatina Priamus, Lam. 
Buccinum Stercus— Pulicum, Chemn. Conch. 9. t. 120. f. 1026-7. 
This shell is ascertained to belong to a marine mollusc, having a 
horny operculum, and therefore is justly considered to form a 
distinct genus, allied to the Buccina and Struthiolariae. Fig. 545. 

PRISODON. Schum. Hyria, &c. Auct. Fig. 144. 

PRODUCED. (Producius, prominent. ) A term applied to the 
spire of univalve shells, or to any other prominent portion . 

PRODUCTA. Sow. (Productus, produced.) Farn. Brachiopoda, 
Lam. — Descr. Equilateral, inequivalve, thick, striated ; one valve 
generally convex, with the margin inflected, produced ; the other 
valve flat, or slightly convex, with the margin reflected ; hinge 
rectilinear, transverse. — Obs. The peculiarity of this genus, from 
which it derives its name, is the manner in which the anterior 
margins of the valves are drawn out and overwrap each other. 
The genus is only known in a fossil state. Species occur in 
Mountain Limestone, and Transition Limestone of older date. 
P. depressa, fig. 206. 

PROSERPINA. Gray? Fig. 274, represents a small shell be- 
longing to the Helix tribe, to which it is believed, Mr. Gray has 
applied the name Proserpina nitida. We do not know how the 
genus is defined. 

PROTO. Defr. A fossil shell resembling Turritella, but 
having a spiral band reaching to the centre of each valve. P. 
terebralis, Bl. 

PSAMMOBIA. Lam. Fam. Nymphacea, Lam. — Descr. Trans- 
verse, oblong, slightly gaping at both ends ; hinge with two 
cardinal teeth in one valve, one in the other ; ligament sup- 
ported upon a prominent fulcrum ; muscular impressions two in 
each valve, sub-orbicular, distant ; palleal impression with a 
large sinus ; epidermis thin. — Obs. The genus thus described 
includes Psammotjla of Lamarck, which, according to him, only 
differs in the number of teeth, and which he says are but " Psam- 
mobies degenerees." The difference appears to be accidental. 



238 PTEROPODA. 

This genus differs from Tellina in not having a posterior fold in 
the margin. Fig. 100. The species are found in temperate and 
tropical climates. 

PSAMMOCOLA. Bl. (xpa/dfiog, psammos, sand ; cola, an in- 
habitant.) A name given by De Blainville to shells of the genus 
Psammobia, including Psammot^ea of Lamarck. 

PSAMMOTiEA. See Lam, Psammobia. 

PSEUDOLIVA. Sw. A genus of " Eburninse," Sw. thus described : 
"Shell thick, oval, oliviform, veDtricose; spire very short, acute ; 
base with two parallel grooves, one of which forms a notch at the 
base of the outer lip ; suture slightly channelled ; inner lip very 
thick, and turning inwards ; aperture with an internal canal. Con- 
nects the Turbinellid^e with the Volutidje. P. plumbea, 
Chem. 188. f. 1806, 1807." Sw. p. 306. 

PSILOSTOMATA. Bl. The third family of Aporobranchiata, Bl. 
containing no genera of shells. 

PTEROCERAS. Auct. (Urepov,pteron } awing ; /cepae, ceras, horn.) 
Fam Ailees, Lam. — Descr. Turrited, oval, ventricose, thick, tuber- 
culated ; spire short ; aperture oval, terminating in a lengthened 
canal at both extremities ; outer lip thickened, expanded, produced 
into horn-shaped, hollow, thickened spires, with an anterior 
sinus apart from the canal. — Obs. This genus, containing the 
shells commonly called Devil's Claws, Gouty Scorpions, Spiders, 
&c. is distinguished from Strombus by the digitations of the outer 
lip. No fossil species are known. Fig. 405, P. aurantiaca. 

PTEROCYCLOS. Benson. Syn. B. M. p. 133. A genus formed of 
species of Cyclostoma, Auct. which have "a groove or hole at the 
hinder part of the mouth." 

PTEROPODA. Lam. (irrepov, pteron, a wing ; ttovq, pons, a foot.) 
The first order of the class Mollusca, Lam. consisting of molluscs 
whose organs of locomotion consist of a pair of wing-shaped fins. 
This order contains the genera Hyalsea, Clio, Cleodora, Spiratella, 
Cymbulia, and Pneumoderma. To which may be added other 
genera enumerated in explanation of figures 220 to 226. They 
may be thus distinguished. 

1. Atlanta. Shaped like Nautilus, symmetrical. Fig. 220. 



PULVINITES. 239 

2. Spiratella. Spiral, not symmetrical. Fig. 224. 

3. Creseis. Straight, thorn-shaped. Fig. 222. 

4. Vaginula. Straight, widened in the centre ; apex pointed. 

Fig. 225. 

5. Cuvieria. The same ; apex blunt. Fig. 223. 

6. Cleodora. Aperture with three spines ; apex recurved. 

Fig. 221. 

7. Hyal^a. Vaulted, open extremity, three-cornered ; apex 

tridentate. Fig. 226. 

PTEROPODA. Bl. The second family of Nucleobranchiata, Bl. 
the shells of which are described as symmetrical, extremely thin, 
transparent, longitudinally enrolled, either forwards or backwards. 
The animals are remarkable for a pair of broad, flat, natatory 
organs or membranaceous fins, from which the family derives its 
name. It contains, in the system of De Blainville, the genera 
Atlanta, Spiratella, and Argonauta, to which may probably be 
added Pharetrium, Konig ; Entalis, Defrance. 

PULLASTRA. Sow. Fam. Conques Marines, Lam.— -Descr. Equi- 
valve, ovate or oblong, transverse, inequilateral ; hinge with three 
diverging cardinal teeth in each valve, notched at the termina- 
tions ; muscular impressions two in each valve ; palleal impression 
having a large sinus ; ligament external, partly hidden by the dorsal 
margin. — Obs. This genus includes the Venerirupes of Lamarck, 
and several species of his Veneres, they are found in the sand on the 
shores of temperate and tropical climates. Fig. 120, P. textile. 

PULMONOBRANCHIATA. Bl. The first order of the first section 
of Paracephalophora monoica, containing the families Limnacea, 
Auriculacea, and Limacinea. 

PULVINITES. Defr. (Pulvinus, a cushion.) Fam. Malleacea, Lam. 
— Descr. Sub-equivalve, inequilateral, compressed, thin, slightly 
gaping posteriorly ; one valve flat, the other rather concave; hinge 
linear, short, divided into perpendicular grooves ; muscular impres- 
sions two, one sub-central, the other above it, nearer the hinge. 
— Obs. This fossil shell is imperfectly known, and it is difficult to 
give a sufficient reason for separating it from Perna. It comes 
from the Baculite limestone of Normandy. Fig. 170, P. Adansonii. 



240 PUPINA. 

PUNCTATED. (Punctatus, spotted or dotted.) For example, see 
Conus Nussatella. Fig. 460. 

PUNCTICULIS. Sw. A sub-genus of " Coronaxis," Sw. (Conus) 
described in Swainson's Malacology, page 311. 

PUNCTURELLA. Lowe. Cemoria, Leach. 

PUPA. Auct. Fam. Colimacea, Lam. ; Limacinea, Bl. — Descr. 
Cylindrical, generally ribbed ; spire long, obtuse, composed of 
numerous slowly increasing whorls ; aperture sub-quadrate, 
rounded anteriorly, entire ; outer lip thickened ; columella plaited. 
— Obs. This genus is composed of land shells very variable in 
form, differing from Bulinus in the numerous slowly increasing 
whorls of the spire, and in the plicae on the columella, and from 
Clausilia in the want of a clausium. Britain, Southern Europe, 
East and West Indies, Mexico, &c. P. Uva. Fig. 291. 

PUPELLA. Sw. A sub-genus of Clausilia. Lardn. Cyclop. Malac. 
p. 334. 

PUPILLA. Leach. A sub-genus of Pupa, P. marginata, Auct. 
(Gray's Turton, p. 196.) 

PUPINA. Vignard. Moulinsia, Grateloup. Fam. Colimacea, 
Lam. — Descr. Pupiform, sub-cylindrical ; last whorl less than the 
preceding ; surface brilliantly polished ; suture of the spire ena- 
melled ; aperture circular ; peritreme thickened ; a notch at the 
base of the inner lip ; operculum horny, spiral. — Obs. The species 
upon which this genus was originally founded, and described in 
the " Annaldes Sciences Naturelles," tome 18, p. 439, (December 
1829,) is a small pupiform shell, having nothing to distinguish it 
but the enamelled suture and the notch in the aperture ; characters 
quite insufficient in themselves for the purpose of generic distinc- 
tion ; at the same time sufficient to lead M. De Ferussac to the 
suspicion of its having an operculum. The next species, described 
by Grateloup under the name of Moulinsia Nunezii, (Ann. Soc. 
Linn. Burd, Nov. 1840), presents more remarkable characters, 
having the spire turned backwards and the penultimate whorl dis- 
proportionately large. Seven additional species have been lately 
brought to this country from the Philippine Islands by Mr. Cum- 
ing. They will be described by the author in the Zoological 



PURPURIFERA. 241 

Proceedings for 1841, and an illustrated monograph of the whole 
genus is published in the Thesaurus Conchyliorum, Part I, by the 
Author. It may be observed that in one of the new species, the 
notch in the peritreme almost disappears, leaving a very slight 
sinus. Fig. 524, 526, 527, 528. 

PURPURA. Auct. ( (< The shell-Jish from which purple is taken" 
Plin.) Fam. Purpurifera, Lam. Entomostomata, Bl. — Descr. 
Oval or oblong, thick ; spire for the most part short, sometimes 
rather longer ; external surface generally sulcated, granulated, 
tuberculated or muricated ; aperture long, oval, somewhat dilated, 
emarginated anteriorly ; outer lip crenated, acute ; columella 
flattened; operculum horny, with the nucleus lateral, thin towards 
the columella. — Obs. True Purpurse to be found in the Lamarckian 
genera Buccinum, Ricinula, and others. They may be generally 
distinguished by the flatness of the columellar lip, and by the short 
canal or emargination, which is not reflected or raised, as in Buc- 
cinum. The species are very numerous and very variable in form, 
inhabiting the seas of temperate and tropical climates. The 
animals secrete a purple liquor, which has been used advantageously 
for dyeing ; the origin of the famous Tyrian dye. Fig. 414, P. 
persica. 

PURPURIFERA. Lam. (Purpura, purple ; fero, to carry.) A 
family belonging to the second section of Lamarck's order Trache- 
lipoda, the shells of which are described as having a very short 
recurved, or ascending canal, or else only a notch between the 
inner and outer lips. The name Purpurifera has been given to 
the family because the animals which it includes, and particularly 
the genus Purpura, contain the colouring matter from which the 
ancients obtained the well known splendid purple. This family 
contains the following genera. 

1. Cassis. Outer lip thick, reflected, denticulated, canal turned 

suddenly over the back ; spire short ; including Cctssidea 
and Cijprcecassis. Fig. 410 to 412. 

2. Cassidaria. Canal turned gently upwards . Fig. 407, 408. 

3. Oniscia. Inner lip granulated ; canal short. Fig. 409. 

R 



242 PUSIOSTOMA. 

4. Buccinum. Outer lip thickened not reflected ; canal short ; 

including Cyllene and Phos. Fig. 416, 421, 422,425. 

5. Nassa. The same, with a notch or tooth at the extremity of 

the columella ; including Cyclops. Fig. 423, 424. 

6. Dolium. Swelled, grooved spirally ; outer lip not reflected. 

Fig. 420. 

7. Purpura. Aperture large ; columella!' lip flat; including 

Tritonidea. Fig. 414, 415. 

8. Monoceros. The same, with a tooth on the outer lip. 

Fig. 417. 

9. Concholepas. Patelliform ; aperture as large as the shell- 

Fig. 417. 

10. Ricinula. Columellar and outer lips granulated, denti- 

culated, outer lip digitated ; including Tribulus. Fig. 413. 

11. Trichotropis. Hairs on the epidermis, along the keels. 

Fig. 429. 

12. Terebra. Elongated, with a spiral groove near the suture 

of the whorls. Fig. 428. 

13. Bullta. Short; aperture wide; outer lip marginated. 

Fig. 427. 

14. E burn a. Like Buccinum, but the outer lip not thickened. 

Fig. 426. 

15. Harpa. With varices at regular intervals. Fig. 419. 
PUSIA. Sw. A sub-genus of Tiara (Mitra.) (Sw. Malac. p. 320.) 
PUSIODON. Sw. A genus of " Lucerninse," Sw. (Helix) thus 

described : " Shell flattened, smooth ; the body-whorl large, and 
much dilated at the aperture ; spire small, flat, of three or four 
contracted whorls ; aperture very oblique, sinuated, or obsoletely 
toothed at the base of the outer lip, which is spreading and sub- 
reflected ; inner lip obsolete ; umbilicus open. Zonaria Chemn. 
132. f. 1188. auriculata Zool. 111. I. pi. 6." Sw. Malac. p. 330. 
PUSIOSTOMA. Sw. A genus of the family " Columbellinse." 
Sw. Thus described : " general form of Columbella, but the 
outer lip is only toothed in the middle, where it is greatly 
thickened ; inner lip convex between the granular teeth ; punc- 



PYRIFORM. 243 

tata, E. M. 374. f. 4. mendicaria, 375. f. 10. turturina, 314. 
f. 2. fulgurans. Lam." Sw. Malac. p. 313. 

PUSTULARIA. Sw. A genus of " Cyprseinse," Sw. thus de- 
scribed : " Shell generally marked by elevated pustules ; aperture 
narrow and linear ; the extremities more or less produced ; the 
teeth continued beyond, and frequently forming elevated strise 
across the lips. P. Cicercula, P. Globulus." Sw. Malac. p. 324. 

PYGMiEA. Humph. Columbella, Auct. 

PYLORIDEA. Bl. The ninth family of the order Lamelli- 
branchiata, Bl. the shells of which are described as nearly always 
regular, rarely otherwise, nearly always e qui valve, gaping at 
both extremities ; hinge incomplete, the teeth becoming gradually 
obsolete ; two distinct muscular impressions ; palleal impression 
very flexuous posteriorly. This family is divided into : Section 
1. Ligament internal ; Pandora, Thracia, Anatina, Mya, Lutricola. 
Section 2. Ligament external ; Psammocola, Soletellina, Solen, 
Sanguinolaria, Solenocurtus, Solenimya, Panopsea, Glycimens, 
Saxicava, Byssomya, Rhomboides, Hiatella, Gastrochsena, Cla- 
vagella, Aspergillum. 

PYRAMIDAL. (Pyramidalis.) Resembling a pyramid in form. 
Ex. Cerithium Telescopium, fig. 378. 

PYRAMIDELLA. Lam. (A little pyramid.) Fam. Plicacea, 
Lam. Auriculacea, BL— Bescr. Pyramidal, smooth, polished ; 
spire long, pointed, composed of numerous whorls ; aperture 
small, modified by the last whorl, rounded anteriorly ; outer lip 
slightly expanded ; columella tortuous, with several folds. This 
is a genus of small, polished, marine shells. Pyramidella Tere- 
bellum, fig. 342. 

PYRAZUS. Montf. Potamis, Brongniart. 

PYRELLA. Sw. A genus consisting of Turbinella Spirilla, Auct. 
and similar species, having a long channel, a pyriform outline, 
and one strong plait at the base of the columella, the apex of the 
spire is enlarged. P. Spirillus, fig. 384. (The proper term 
would be Spirilla.) 

PYRIFORM. (Pyrum, a pear; forma, shape.) Shaped like a 

r 2 



244 RADICATED. 

pear, i. e. large and rounding at one end, and gradually tapering 
at the other. Ex. Pyrula, fig. 390. 
PYRGO. Defr. A genus of microscopic Foraminifera. 
PYRGOMA. Auct. (Ylvpyog, pyrgus, a tower.) Order, Sessile 
Cirripedes, Lam. — Descr. Composed of a single conical, hollow 
paries, with a small aperture closed by an operculum of four 
valves, and supported upon a cup-shaped base. — -Obs. The genera 
into which Leach has divided this genus are Pyrgoma, Adna, and 
Megatrema ; his genera Nobia and Savignium differ in having but 
two valves for the operculum. Pyrgoma differs from Creusia 
in having the body of the shell, i. e. the parietal cone, simple, 
not divided into valves. Fig. 31. 

PYRGOPOLON. De Montfort's figure of this genus appears as if 
it had been drawn from the nucleus of a Belemnite. 

PYRULA. Auct. {A little pear.) Earn. Canalifera, Lam. Siphon- 
ostomata, Bl. — Descr. Thin, oblong, pyriform, ventricose towards 
the spire, gradually tapering towards the anterior of the aper- 
ture, spire short, consisting of few volutions ; aperture wide, 
terminating in a long, narrow, open, canal ; columella smooth, 
elegantly tortuous. — Obs. The above description includes all the 
true Fig shells, which present a most graceful form ; the contour 
partaking of the peculiar curve, called by painters the line of 
beauty. P. Ficus, fig. 390. 

PYRUM. Humph. Pyrula, Lam. 

QUADRATE. (Quadratus.) Square, applied when the outline of 
shells is formed by nearly straight lines meeting at right angles. 

QUADRILATERAL. Four-sided. 

QUINQUELOCULINA. D'Orbigny. A genus of microscopic 
Foraminifera. 

BADIATING. (Radians.) A term applied to the ribs, striae, bands 
of colours, &c. when they meet in a point at the umbones of a 
bivalve shell, and spread out towards the ventral margin. — Ex. 
The bands of colour in Tellina radiata, fig. 105. 

RADICATED. (Radix, a root.) Attached, and as it were rooted by 
means of a fibrous byssus. 



RANELLA. 



245 



RADIOLATA. Lam. A family belonging to the order Cepha- 
lopoda, Lam. The shells belonging to it are described as dis- 
coidal, with the spire central, and the chambers radiating from 
the centre to the circumference. This family contains the genera 
Rotalina, Lenticulina, and Placentula. 

RADIOLITES. A genus belonging to the family of Rudistes, 
differing from Sphserulites, in having both the valves more conical. 

RADIUS. Montf. A genus composed of Ovulum Volva, Auct. 
and other similar species, having a long attenuated canal at each 
extremity. Fig. 442. 

RADIX. Montf. A genus composed of species of Limn^ea, 
having a short spire and wide aperture. — Ex. L. aperta, fig. 309. 

RAMIFIED. (Ramus, a branch.) Branched out.— Ex. The varices 
of some Murices, &c. 

RAMPHIDOMA Schum. Pollicipes, Leach 

RAMOSE. (Ramosus, branched.) Spread out into branches. 
Ex. Murex inflatus, fig. 395. 

RANELLA. Auct. (Rana, a frog.) Fam. Canalifera, Lam. 
Siphonostomata, Bl. — Descr. Oval or oblong, depressed, thick, 
with two rows of continuous varices, skirting the outline, one 
on each side ; spire rather short, pyramidal, acute, aperture 
oval, terminating in a canal at each extremity ; outer lip thickened 
within, crenulated, or denticulated, forming an external varix ; 
inner lip spread over a portion of the body whorl. — Obs. The 
shells composing this well-defined genus, are for t lie most part 
covered with tuberculations, and granulations, and from the colour 
and squat shape of some species, have been likened to frogs. The 
Ranellse are mostly inhabitants of the East Indian seas. The few 
fossil species known, occur in the tertiary beds. The two conti- 
nuous rows of varices skirting the spire, distinguish this genus from 
Triton, which it nearly approaches, and into which some species 
run by imperceptible gradations. Fig. 393, 394. Many new 
species were brought to this country by Mr. Cuming, and are 
represented in parts 84, 85, 88, 89, 92, 93, of the author's 
Conchological Illustrations. 



246 REOPHAX. 

RANGIA. Desmoulins. Gnathodon, Gray. 

RAPANUS. Schum. ? A genus consisting of species of Pyrula, 
Auct. which are thin, much inflated, with short canals. Fig. 
389, P. papyracea. 

RAPELLA. Sw. A genus of " Pyrulin8e, ,, Sw. thus described : 
i( Shell ventricose, generally thin, almost globose; the base 
suddenly contracted, and forming a short canal, the channel 
almost obsolete ; umbilicus large, partly concealed by the inner 
lip. R. papyracea. En. Meth. 436, f. 1." Sw.p. 307. Rapanus, 
Schum. Fig. 389. 

RAPHANISTER. Montf. A species of madrepore, described as 
a shell. 

RAPUM. Humph. Turbinella, Lam. 

RAZOR SHELL. A common name by which shells of the genus 
Solen, are known in the market. 

RECTILINEAR. (Rectus, right; linea, a line.) In a straight 
line. Ex. The hinge of Byssoarca Nose, fig. 132. 

RECURVED. (Re, back ; curvo, to bend.) Turned backwards ; 
the term, when applied to symmetrical conical univalves, is used 
to signify that the apex is turned towards the posterior margin, 
as in Emarginula, fig. 24 1 . 

REFLECTED. (Reflected, to fold back.) Turned, or folded back- 
wards. Ex. The edge of the outer lip in Bulinus, fig. 282, is 
reflected, while that of Cyprsea, fig. 445 to 450, is inflected. 

REMOTE. (Remotus, distant.) Remote lateral teeth in a bivalve 
shell, are those that are placed at a distance from the cardinal 
teeth. Ex. The lateral teeth of Aphrodita, (fig. 123.) are remote; 
those of Donax, (fig. 108) are near. 

RENIELLA. Sw. A sub-genus of Malleus. Lardn. Cyclop. Malac. 
p. 886. Gray states it to be only a distorted specimen of Vulsella, 
Syn. B. M. p. 145. 

RENIFORM. (Ren, a kidney ; forma, shape.) Shaped like a 
kidney. Ex. The aperture of Ampullaria, fig. 318. 

RENULINA. Lam. A genus of microscopic Foraminifera. 

REOPHAX. Montf. A genus of microscopic Orthocerata, Bl. 



RHOMBOIDAL. 



24! 



REPENT. (Repens, creeping.) A term applied to those shells, 
which, being attached by the whole length of their shell, give the 
idea of creeping or crawling. Ex. Verm ilia, fig. 7. 

RETICULATED. (Reticulars.) Resembling net-work. 

RETIFERA. Bl. The first family of the order Cervicobranchiata, 
Bl. containing the genus Patella. 

REVERSED or Sinistral Shells, are those in which the aperture 
is on the left side of the shell, while it is held with the mouth 
downwards, and towards the observer. Ex. Balea, fig. 296. 
Attached bivalves are said to be reversed, when the left valve is 
free, instead of the right; a circumstance which sometimes occurs 
in Chama and Ostrea. 

RHEDA. Humph. Hyal^a, Lam. 

RHINOCLAVIS. Sw. A genus of « Cerithinee," Sw. thus de- 
scribed : " channel curved backwards, in an erect position; inner 
lip very thick, with a tumid margin; pillar generally with a 
central plait ; operculum ear-shaped ; lineatum. En. M. 443, fig. 
3, Vertagus. lb. f. 2, subulatum. Lam. No. 23, fasciatum. 
Mart. 157, f. 1481. obeliscus, En. Meth. 443, f. 4 ; aluco, lb. 
f. 5, (Aberrant,) semi-granosum. lb. 443, f. 1, asperum. Mart. 
157, f. 1483. 

RHINOCURUS. Montf. A genus of microscopic Foraminifera. 

RHINODOMUS. Sw. A genus of " Scolymime," Sw. thus 
described : No internal grove ; shell clavate ; the spire longer 
than, or equal with the aperture ; the whorls with ridges or 
longitudinal varices, and rendered hispid by transverse grooves ; 
inner lip wanting ; pillar with a terminal fold ; aperture striated ; 
outer lip with a basal sinus. R. senticosus, Chem. tab. 193. f. 
1864-1866, 

RHIZORUS. Montf. A genus described from a microscopic shell, 
appearing to be a cylindrical Bulla. 

RHODOSTOMA. Sw. A sub-genus of " Turbininse," Sw. p. 344. 

RHOMBOIDAL. (pofipoEidoQ, rhomboeidus.) Having a rhombic 
form, i. e. four-sided ; two sides meeting at acute, two at obtuse, 



248 



RISSOA. 



angles. Conchologists are not very strict in the application of 
this term, for, indeed, a perfect rhomboidal figure could not be 
found among all the testaceous productions of the sea. 

RHOMBOIDES. Bl. A genus described as resembling Byssomya 
in the shell, but differing in the animal. Mytilus rugosus, 
Gmelin. Hypogjsa barbata, Poli. 

RHOMBUS. Montf. (pofi/3oQ i rhombos, a rhomb.) A genus con- 
sisting of species of Conus, having a rhomboidal or quadrilateral 
form and a coronated spire. Ex. Conus nocturnus, fig. 459. 

RICINULA. Lam. (Resembling the seed-vessel of the Ricinus.) 
Fam. Purpurifera, Lam. Entomostomata, Bl. — Bescr. Sub-ovate, 
thick, tuberculated ; spire short ; aperture narrow, terminating 
anteriorly in a short canal ; outer-lip thickened, denticulated 
within, digitated without ; columellar lip spread over a portion 
of the body whorl, and granulated. — Obs. This interesting genus 
is composed of some neat little shells allied to Purpura, from 
which they are distinguished by the finger-like branching of the 
outer lip, and the granulations of the columella. Fig. 413, R. 
Horrida. 

RIGHT. See Dextral. 

RIMULA. Defr. A genus consisting of a minute species of 
Emarginula, Auct. which has a fissure near the margin, but 
not reaching it. R. Blainvillii, fig. 243. 

RIMULINA. D'Orbigny. A genus of microscopic Foraminifera. 

RINGICULA. Deshayes. A genus founded on Auricula ringens 
of Lamarck and several small fossils, resembling in some respects 
Pedipes of Adanson ; they would belong to Tornatella, were it not 
for the lips being thickened and marginated, fig. 540, A. ringens. 

PISSOA. Freminville. Fam. Ellipsostomata, Bl. Melaniana, 
Lam.— Bescr. Oblong, turrited, acuminated ; spire long, con- 
sisting of numerous whorls ; aperture round or oval, pointed 
posteriorly, dilated anteriorly ; outer lip slightly thickened, 
emarginated, operculum horny — Obs. The Rissose are small 
white, marine shells, considered by some authors as resembling 



ROTELLA. 249 

Melanioe, but placed by Sowerby near the Scalariee. They are 
principally from the shores of the Mediterranean, and are also 
very abundant on the British shores, as well as the East and West 
Indian. Fig. 346, R. reticulata. 

ROBULUS. Montf. A genus of microscopic Foraminifera. 

ROLLUS. Montf. A genus composed of Conus Geographus, 
Auct. fig. 462, and other species, rather cylindrical in form, and 
having a coronated spire. 

ROSALINA. D'Orb. A genus of microscopic Foraminifera. 

ROSTELLARIA. (From rostrum, a beak.) Fam. Alatse, Lam. 
Siphonostomata, Bl. — Descr. Turrited, fusiform, thick, smooth 
or ribbed ; aperture oval, terminating anteriorly in a long canal, 
posteriorly in a channel running up the spire ; outer lip dilated, 
thickened, sometimes digitated, running up all or part of the 
spire, with a sinus near the anterior canal ; inner lip smooth, 
spread over part of the body whorl and of the spire. The Red Sea 
and the Indian Ocean produce the few known species of this genus. 
—Obs. Hippochrenes is the name given by De Montfort, to 
those fossil species which have the outer lip simple and very much 
dilated. R. curvirostrum, fig. 412. Aporrhais is a name given 
to another proposed genus, composed of Rostellaria pes-pelecani, 
Auct. fig. 404. and similar species. 

ROSTRATED. (From rostrum, a beak.) Having one or more 
protruding points, as Tellina rostrata. 

ROTALIA. Lam. A genus of microscopic Foraminifera. The 
same as Rotalites of De Montfort. 

ROTELLA. Lam. {A little wheel.) Fam. Turbinacea, Lam — 
Descr. Orbicular, generally smooth, shining ; spire conical, de- 
pressed, short ; aperture subtrigonal ; outer lip thin, angulated 
near the centre ; inner lip spread over the surface of the whorls, 
forming a thickened disc. Operculum horny, orbicular, spiral, with 
numerous whorls. — Obs. The pretty little shells thus described 
are found in seas of tropical climates. They are distinguished from 
other genera of the family by their lenticular form and the orbicular 
callosity of the under surface. Fig. 357, R. vestiaria. 



250 SALPACEA. 

RUDISTES. Lam. A family of the order Conchifera Mono- 
myaria, Lam. the shells of which are described as irregular, very 
inequivalve, without distinct umbones ; the ligament, hinge and 
animal entirely unknown. The shells contained in this family 
may be thus distinguished. 

1. Calceola. Large valve conical ; attached by a flat space 

between the umbones, which form the extremities of the 
shell. Fig. 194. 

2. Hippurites. Large valve cylindrical, with two internal 

lobes or varices. Fig. 198. 

3. Sph^erulites. Large valve attached, including Radiolites. 

Birostrites is proved to be the cast of a Sphserulites. Fig. 
193, 196. 

4. Hipponyx. Flat valve attached, upper valve conical. Fig. 

199, 200. 

RUDISTES. Bl. The second order of the class Acephalophora, 
Bl. containing the genera Sphserulites, Crania, Hippurites, Radio- 
lites, Birostrites and Calceola. 

RUDOLPHUS. Lam. Monoceros, Auct. 

RUFOUS. Reddish brown. 

RUGOSE. Rough, rugged. 

RUPELLARIA. Fl. de Belvue. An unfigured shell placed by De 
Blainville in a division of the genus Venerirupis. 

RUPICOLA. Fl. de Belvue. A shell described by De Blainville as 
an equivalve, terebrating species of Anatina. A. rupicola, Lam. 

SABINEA. A genus of shells resembling small species of Littorina, 
as L. Ulvse, &c. of our shores. 

SADDLE OYSTER. Placuna Sella, so called on account of a 
resemblance in shape to a saddle ; the part near the umbones 
being flat, and the ventral margins being turned up in a sort of 
fluting or peak. 

SAGITTA. (An arrow.) An ancient name for Belemnites. 

SALIENT. (Saliens.) Jutting out, prominent. 

SALPACEA. Bl. The second family of the order Heterobran- 
chiata, Bl. containing no genera of shells. 



SCABRICULA, 251 

SANDALINA. Schum. Crepidulina, Lam. A genus of micro- 
scopic Foraminifera. 

SANGUINOLARIA. Lam. (Sanguis, blood.) Fam. Nymphacea, 
Lam. Pyloridea, Bl. — Bescr. Equivalve, inequilateral, transverse, 
sub-ovate, rounded anteriorly, sub-rostrate posteriorly, compressed, 
thin, covered with a shining epidermis, gaping at the sides ; hinge 
with two cardinal teeth in each valve, and an external ligament 
supported upon a prominent fulcrum ; muscular impressions two 
in each valve, lateral, irregular, palleal impressions with a large 
sinus. — Obs. This description is made to exclude some of La- 
marck's species of Sanguinolaria, such as S. occidens, S. rugosa, 
which are Psammobise ; and to include others which he has left 
out. The Sanguinolarise are sub-rostrated posteriorly, while the 
Psammobise are sub-quadrate and have a posterior angle. Fig. 98, 
S. rosea. Sandy shores of tropical climates. 

SARACENARIA. Defr. A genus of microscopic Foraminifera. 

SA VIGNIUM. Leach. A genus of Sessile Cirripedes, described as 
composed of four valves soldered together, and a convex bivalve 
operculum ; the ventral and posterior valve on each side being 
soldered together, in other respects resembling Pyrgoma. 
Fig. 30. 

SAXICAVA. Fl. de Belvue. Journ. de Ph. an. 10. (Saxum, a 
stone ; cava, a hollow.) Fam. Lithophagidoe, Lam. Pyloridea, 
Bl. — Bescr. Transverse, irregular, generally oblong, inequilateral, 
sub-equivalve, gaping anteriorly ; ligament external ; muscular 
impressions two, lateral ; palleal impression interrupted, not 
sinuated; hinge, when young with sometimes two or three minute, 
obtuse, generally indistinct, cardinal teeth ; which become obso- 
lete when full grown. — Obs. Several genera have been founded 
only upon the difference between the young and old shell of the 
same species of this genus. The Saxicavse are found in the little 
hollows of rocks; in cavities on the backs of oysters, of roots of sea- 
weeds, &c. in northern and temperate climates. S. rugosa, fig. 94. 

SCABRICULA. Sw. A sub-genus of Mitrae, consisting of species 
which have a roughened external surface, &c. Sw. Malac. 
p. 319. 



252 SCALPELLUM. 

SCABROUS. Rough. 

SCALA. Klein. Scalaria, Auct. 

SCALARIA. Auct. Fam. Scalariana, Lam. Cricostomata, Bl. — 
Descr. Turrited, oval or oblong ; spire long, composed of rounded, 
sometimes separate whorls, surrounded by regular concentric 
ribs ; aperture oval, peristome reflected continuous, entire. — Obs. 
The typical species of this genus, commonly called the Wentletrap, 
(S. pretiosa) is celebrated for the beautiful appearance caused by 
the numerous ribs encircling the whorls, and formerly produced 
an immense price in the market. It is brought from China. 
There are many smaller species, some of which are equally elegant. 
Fig. 351, S. Pallasii, Kiener. 

SCALARIANA. Lam. A family belonging to the first section of 
the order Trachelipoda, Lam. The shells belonging to it are 
described as having the inner and outer lips continuous, without 
a canal, emargination, or other division. In this respect the 
family is stated to differ from the Turbinacea, and is therefore 
separated. The genera may be distinguished as follows: — 

1. Vermetus. Irregularly twisted, like Serpula. Fig. 345. 

2. Eulima. Pyramidal ; apex contorted ; including Bonellia. 

Fig. 347, 348. 

3. Rissoa. Pyramidal, straight, consisting of few whorls. 

Fig. 346. 

4. Scalaria. With external varices. Fig. 351. 

5. Cirrus. Trochiform. Fig. 349. 

6. Enomphalus. Orbicular. Fig. 350. 

7. Delphinula. Few whorls, rapidly increasing. Fig. 352. 
SCALLOP. The common name for shells of the genus Pecten, the 

larger species of which were worn by pilgrims to the Holy Land 
in the time of the Crusades. 
SCALPELLUM. Leach. (A little knife or lancet.) Order, Pedun- 
culated Cirripedes, Lam. — Descr. Flat, quadrated, acuminated, 
composed of thirteen valves, one dorsal, arcuated ; one pair 
apicial, acuminated ; one pair ventral ; two pair lateral, small, 
sub-quadrate ; pedicle scaly.— Obs. This genus and Smilium, 
are the only Pedunculated Cirripedes which have thirteen valves ; 



SCISSURELLA. 253 

in the latter genus, which we think should at any rate be united 
to this, the valves are somewhat differently placed, and the pedi- 
cle is said to be smooth. Fig. 35, Scalpellum vulgare. British. 

SCAPHA. Klein. (A boat.) Navicella, Auct. 

SCAPHANDER. Montf. Bulla lignaria, Auct. Fig. 251. 

SCAPHELLA. Sw. A genus of the family " Volutinse," Sw. thus 
described: " Shell smooth, almost polished ; outer lip thickened 
internally ; suture enamelled ; lower plaits the smallest ; apex of 
the spire various : 1. fusiformis, Sw. Bligh. Cat. 2. undulatus. 
Ex. Conch, pi. 27. 3. Junonia, Ex. Conch, pi. 33. 4. stromboides. 
5. papillosa. Sw. Sow. gen." Sw. Malac. p. 318. 

SCAPHITES. (A boat.) Fam. Ammonacea, Lam. and Bl. — 
Descr. Convolute, chambered, closely related to the Ammonites, 
from which it differs in the last whorl being eccentrically straight- 
ened, and lengthened, and again incurved towards the extremity. 
Only known in a fossil state. Fig. 481, S. sequalis. 

SCAPHULA. Sw. A genus of " Olivine," Sw. thus described: 
" Spire very short, thick, obtuse, and not defined ; aperture very 
wide, with only two or three oblique plaits at the base. Sw. 
patula, Sow. Tank. Cat. 2331. (5.)" (Sw. p. 322.) 

SCARABUS. Montf. (Scarabceus, a kind of beetle.) Fam. Colima- 
cea, Lam. Auriculacea, Fer. — Descr. Oval, somewhat compressed, 
smooth, with slightly raised varices ; spire equal in length to the 
aperture, pointed, consisting of numerous whorls ; aperture ovate, 
rounded anteriorly, pointed posteriorly, modified by the last 
whorl ; outer lip sub-reflected, with several prominent folds on 
the iuner edge ; inner lip spread over a portion of the body 
whorls, with several prominent folds. — Obs. The shells of this 
genus are found like Auriculae, in marshy places. C. imbrium is 
said to have been found on the tops of mountains, by Captain 
Freycinet. Fig. 299*, S. imbrium. 

SCHIZODESMA. Gray. A genus composed of species of Mactra, 
Auct. with the ligament placed in an external slit. Fig. 8, M. 
Spengleri. 
SCISSURELLA. D'Orbigny. (Scissus, cut.) Fam. Turbinacea, 



254 SEDENTARY ANNELIDES. 

Lam. — Descr. Sub-globose, umbilicated, with a spiral groove 
terminating at the margin of the outer lip in a slit ; spire short ; 
aperture oval, modified by the last whorl ; outer lip sharp, with 
a deep slit near the spire. Recent on the coasts of Britain ; fossil 
in the Calcaire-grossier. — Obs. This genus, consisting of small 
shells, is known from Pleurotomaria by the shortness of the spire ; 
the latter genus being trochiform. Fig. 340, S. elatior. 

SCOLYMUS. Sw. A genus of the family " Scolyminse." Sw. 
(Turbinella) thus described : " Sub-fusiform, armed with foliated 
spines ; spire shorter ; pillar with distinct plaits in the middle." 
The species enumerated are, " cornigerus, pugillaris, Globulus, 
Rhinoceros, ceramicus, Capitellum, umbilicaris, mitis." Sw. 
Malac.p. 304. 

SCORTIMUS. Montf. A genus of microscopic Foraminifera. 

SCROBICULARIA, Schum. Species of Lutraria, Act. of a 
rounded shape. Ligula, Leach. 

SCROBICULATED. (Scrobiculus, a little ditch or furrow.) Having 
small ditches or furrows marked on the surface. 

SCUTELLA. Brod. {Scutellum, a little shield.) Fam. Phyl- 
lidiana, Lam. —Descr. Shaped like Ancylus, pearly within ; apex 
posteriorly inclined, central, involute ; muscular impressions two, 
oblong, ovate, lateral ; aperture large, ovate. — Obs. This genus 
is intermediate between Ancylus and Patella ; while in the aspect 
of the beak, the observer is reminded of Navicella. 

SCUTIBRANCHIATA. Bl. {Scutum a shield ; branchiae, gills.) 
The third order of Paracephalophora Hermaphrodita, Bl. contain- 
ing animals with patelliform, but not symmetrical shells, and 
divided into the families Otidea and Calyptracea. 

SCUTUM. Montf. {A shield.) Parmophorus elongatus, Lam. 

SECURIFORM. (Securis, an axe; forma, shape.) Hatchet- 
shaped. Ex. Pedum, fig. 179. 

SEDENTARY ANNELIDES. Lam. The third order of the 
class Annelides, Lam. distinguished from the two other orders by 
the circumstance of the animal being enveloped by a shelly tube 
which it never entirely leaves. The order is divided into the 



SERPULA. 



255 



families Dorsalra, Maldania, Serpulacea, and Amphitrites. Fig. 1 

to 13. 
SEA DATE. The common name for Pholas Dactylus in the 

market, given to it on account of its cylindrical shape. Fig. 35. 
SEGMENTINA. Flem. Nautilus Lacustris, Montagu. Test. 

Brit. Planorbis nitidus, Drap. tab. 2. Fig. 17 to 19. 
SEMICORDATE. Half heart-shaped. 
SEMIDISCOLDAL. Forming the half of a circular disc. 
SEMILUNAR. Half moon shaped. 
SENECTUS. Humph. A genus of " Senectinse," thus described 

by Swainson : " Imperforate ; the base produced into a broad 

flat lobe, spire rather elevated and pointed ; the whorls convex ; 

aperture perfectly round ; not more oblique than Helix ; inner 

lip entirely wanting, imperialis. Mart. 180. f. 1790. marmoratus. 

1. M. 448. f. 1." Sw. p. 348. 
SEMIPHYLLIDIANA. Lam. The second family of the order 

Gasteropoda, Lam. the genera of which are distinguished as 

follows :— 

1. Umbrella, round, flat ; apex central, muscular impression 

not interrupted. Fig. 233. 

2. Pleurobranchus, apex lateral, sub-spiral. Fig. 232. 
SENOCLITA. Schum. Cineras, Leach. 

SEPTARIA. Lam. See Teredo. 

SEPTUM. (Lat.) An enclosure, applied to the thin plate of Cre- 
pidula, fig. 239 ; also to the plates dividing the chambers of 
multilocular shells. 

SERAPHS. Montf. Terebellum convolutum, Lam. Fig. 451. 

SERPULA. Auct. (A little serpent.) Fam. Surpulacea, Lam. 
— Descr. Tubular, narrow, pointed at the apex, gradually widen- 
ing towards the aperture, attached irregularly, sometimes spirally, 
twisted, imbricated ; keeled or plain ; aperture generally round, 
with the edge simple, or angulated by the termination of external 
ribs or keels. ~~Obs. This description is intended to include the 
genera Serpula, Spirorbis, Vermilia, Galeolaria, &c. The 
Serpulse abound in all seas, on rocky shores, at any time covered 



256 SESSILE CIRRIPEDES. 

by water, attached to any kind of marine substance, whether 
moveable or stationary. The fossil species occur in almost all 
tertiary strata. Fig. 4 to 7. 
SERPULACEA. Lam. The fourth family of the order Sedentary 
Annelides, Lam. containing the following genera of tubular, 
irregular shells. 

1. Serpula, attached by a small portion of the shell. Fig. 4. 
2 Spirorbis, attached by the whole length, coiled. Fig. 5. 

3. Galeolaria, with the open extremity raised, and the 

aperture tongue-shaped. Fig. 6. 

4. Verm i li a, attached by the whole length, straight or waved. 

Fig. 7. 

5. Spiroglyphus, which hollows a bed in the body to which 

it is attached. Fig. 8. 
Sowerby. (Genera of Shells, published at 50, Great Russell 
Street, Bloomsbury,) gives satisfactory reasons for re-unit- 
ing the whole of the preceding under the name Serpula. 

6. Magilus, which burrows in coral; outer lip reflected. 

Fig. 9 to 10. 

7. Leptoconchus, outer lip reflected. Fig 11. 

8. Stylifer, spiral, thin, globular, living in Starfish, Fig. 

12, 13. 

The three last genera should certainly find some other place 

in the system. 

SESSILE CIRRIPEDES. Lam. (Sessilis, low, dwarfish.) An 

order of Cirripedes, consisting of those which are attached by the 

base of the shells, containing the genera Tubicinella, Balanus, 

Coronula, Acasta, Pyrgoma, Creusia. To which may be added 

some other genera enumerated in explanation of figures 14 to 33. 

The shells of the Sessile Cirripedes consist of two different sets 

of valves : 1st. The parietal valves, or pieces arranged in a circle, 

side by side, around the body of the animal, (an arrangement 

designated coronular by De Blainville.) 2nd. The opercular valves, 

or pieces placed so as to enclose the aperture. Between those 

opercular valves the cilise protrude which characterize the class. 



SIGARETUS. 



257 



Besides these two sets of valves, there is generally a shelly plate, 
serving as a sort of foundation to the rest. The Sessile Cirripedes 
may be thus arranged. 

1. Tubicinella. Six parietal valves, tube-shaped, opercular 

valves perpendicular. Fig. 14. 

2. Coronula. Six parietal valves, opercular valves horizontal. 

Fig. 15, 16, 17, 18. 
These two genera fix themselves in the skin of the Whale. 
The latter has been divided into the genera Chelonobia, 
Cetopirus, Diadema, and Chthalamus. 

3. Platylepas. Valves divided, each having a prominent 

internal plate. Fig. 19. 

4. Clitia. Parietal valves four, opercular valves two, valves 

dove-tailed into each other. Fig. 20. 

5. Elmineus. Parietal valves four, opercular valves four. 

Fig. 22. 

6. Conia. Parietal valves four, thick and porous at the base. 

Fig. 21. 

7. Octomeris. Parietal valves eight. Fig. 24. 

8. Catophragmus. Parietal valves numerous, irregular. 

Fig. 23. 

9. Balanus. Parietal valves six ; opercular valves four, placed 

against each other conically in pairs. This genus has 
been divided into Acasta, Conoplea, Chirona, and Balanus. 
Fig. 25, 26, 27. 

10. Creusia. Parietal valves four, supported on the edge of a 

funnel-shaped cavity. Fig. 28. 

11. Pyrgoma. Paries simple, supported on a cavity. This 

genus has been divided into the genera Nobia, Savignium, 
Pyrgoma, Adna, Megatrema, and Daracia. Fig. 29 to 33. 

SETIFEROUS. Hairy. 

SHANK SHELL. The vulgar name for the shell designated Murex 
Rapa. It is used in Ceylon for ornamental purposes. 

SIDEROLITES. Montf. A genus of microscopic Foraminifera. 

SIGARETUS. Lam. Fam. Macrostomata, Lam. — Bescr. Sub- 



258 



SINUOUS. 



orbicular, oblique, haliotoid, thick ; spire depressed, consisting 
of two or three rapidly increasing whorls ; aperture wide, entire, 
modified by the last whorl, the width exceeding the length ; 
columella tortuous ; inner lip spread thinly over part of the body 
whorl; epidermis thin.— Obs. This genus is distinguished from 
Natica, by the width of the aperture, and the absence of the 
umbilical callosity. It may be known from Stomatia, and 
Stomatella, by the texture, which in Sigaretus, is never pearly as 
in Stomatia, the former being partly an internal shell. Fig. 
334, S. concavus. Mostly brought from tropical climates. 
SILIQUA. Megerle. (A husk, or pod.) Leguminaria, Schum. 
A genus composed of species of Solen, Auct. which have an 
internal rib. Fig. 51, Solen radiat us. 
SILIQUARIA. Brug. Fam* Cricostomata, Bl. Dorsalia, Lam. 
— Descr. Tubular, rugose, spiral near the apex, irregularly 
twisted near the aperture, with a longitudinal fissure radiating 
from the apex, and proceeding through all the whorls and 
sinuosities of the tube. — Obs. This genus was included in 
Serpula by Linnseus, from which, however, it is distinguished by 
the longitudinal slit, fig. 1. S. anguina. The recent species are 
found in the sponges with siliceous spiculse, in the Mediter- 
ranean ; the fossils in tertiary beds. 
SIMPLE. {Simplex, lat.) Single, entire, uninterrupted, un- 
divided. 
SIMPLEGAS. Mont. 1, 83. {Simplex, simple ; yaarrjp, y aster, 
belly.) A genus described by De Blainville, as being discoidal, 
and having the spire uncovered like Ammonites, but having the 
chambers divided, by simple septa, like Nautilus. — Obs. The 
septa of the shell named Simplegas by De Montfort, are evidently 
sinuous, according to his figure. Fig. 475, S. sulcata. 
SINISTRAL. {Sinister, left.) On the left side. A sinistral shell 
is a reversed one. The sinistral valve of a bivalve shell may be 
known, by placing the shell, with its ligamentary or posterior 
part towards the observer ; the sides of the shell will then 
correspond with his right and left side. 
SINUOUS. Winding, serpentine. The septa of Ammonites are 



SIPHONOSTOMATA. 259 

sinuous. The muscular impression of the mantle, or palleal 
impression of some bivalve shells, is sinuated near the posterior 
muscular impression. 
SINUS. (Sinus, a winding, or bay.) A winding or tortuous 
excavation. The sinus in the outer lip of Strombus, fig. 406; and 
that in the muscular impression of Venus, will be indicated by 
the letter s. 
SIPHON. (Bicpov, siphon.) A pipe, or tube. A shelly tube 
passing through the septa of chambered shells. It is said to be 
dorsal, central, or ventral, according to its situation near the 
outer, or inner parts of the whorl. See Introduction. 
SIPHONAL SCAR. The name applied by Mr. Gray, to the open- 
ing or winding sinus in the palleal impression of a bivalve 
shell, in the place where the siphonal tube of the animal 



SIPHONARIA. Sow. (2i0ov, siphon.) Fam. Phyllidiana. 
Lam. Patelloidea, Bl. — Bescr. Patelliform, depressed, inclining 
to oval, ribbed ; apex nearly central, obliquely inclining towards 
the posterior margin ; muscular impression partly encircling 
the central disc, but interrupted in front, where the head of the 
animal reposes, and at the side by a siphon, or canal passing 
from the apex to the margin.— Obs. This siphon, which is in 
some species very distinct, serves to distinguish this genus from 
Patella. S. Sipho, fig. 231*. 
SIPHONOBRANCHIATA. Bl. (Siphon, and Branchia, gills.) 
The first order of Paracephalophora Dioica, Bl. divided into 
the families Siphonostomata, Entomostomata, and Angiostomata. 
SIPHONOSTOMA. Guild. A sub-genus of Pupa, consisting of 
several elongated species, which have the aperture detached from 
the whorls ; sucli as P. costata, and fasciata. 
SIPHONOSTOMATA. Bl. (S^ov, siphon; aro^ia, stoma, mouth.) 
The first family of Siphonobranchiata, Bl. the shells of which 
are extremely variable in form, but always have a canal or notch 
at the anterior extremity of the aperture. This family partly 
answers to the Canalifera of Lamarck and the genus Murex in 

s 2 



260 SOLEN. 

the system of Linnaeus. It contains the genera Pleurotoma, 
Rostellaria, Fusus, Pyrula, Fasciolaria, Turbinella, Columbella, 
Triton, Murex, Ranella, and Struthiolaria. 

SIPHUNCLE. (Siphunculus.) A small siphon. 

SISTRUM. Montf. Ricinula, Auct. fig. 413. 

SKENEA. Flem. A genus including some species of Euomphalus 
and Cirrus. 

SMILUM. Leach. Fam. Pedunculated Cirripedes. — Descr. 
Thirteen pieces, ten of which are in pairs, lateral, subtriangular; 
one posterior dorsal, linear ; all smooth ; peduncle hairy. — Obs. 
This genus is distinguished from Pentelasmis, by the number of 
its valves, and from Scalpellum, by the hairy peduncle. S. 
Peronii, fig. 36. 

SNAIL. The common garden Snail, so destructive to our vege- 
tables, belongs to the genus Helix. The water snail, found in 
ponds, is Planorbis. 

SOL. Humph. A genus consisting of several species of the 
genus Trochus, and corresponding with the sub-genus Tubi- 
canthus, Sw. Malac. Fig. 349. 

SOLARIUM. Auct. {A terrace, or gallery.) Fam. Turbinacea. 
Lam. Goniostomata, Bl. — Descr. Discoidal beneath, conical 
above, with a wide umbilicus, the spiral margin of which is 
angulated and crenulated ; aperture trapezoidal ; peritreme thin, 
sharp ; columella straight ; operculum horny, subspiral. — Obs. 
The Solarium Perspectivum, is commonly called the Staircase 
Trochus, from the angulated edges of the whorls being seen 
through the umbilicus, which reaches to the apex, and presents 
the appearance of a winding gallery. The species are not 
numerous, they belong to tropical climates. A few fossil species 
occur in the tertiary formations. Fig. 353, S. Perspectivum. 

SOLDANIA. D'Orb. A genus of microscopic Foraminifera. 

SOLEN. Auct. {J kind of shell-fish, Plin.) Fam. Solenacea, 
Lam. Pyloridea, Bl. — Descr. Bivalve, transversely elongated, 
sub-cylindrical, equivalve, very inequilateral, gaping at both 
extremities, umbones terminal, close to the anterior extremity ; 



SOLENELLA. 261 

hinge linear, with several small cardinal teeth, and a long, exter-. 
nal ligament ; muscular impressions distant, anterior tongue- 
shaped, placed behind the cardinal teeth, posterior irregular, 
sub-ovate ; palleal impression long, bilobed posteriorly. — Obs. 
The above description of the genus Solen, is framed so as to 
admit only those species which are commonly called Razor 
Shells, with the umbones terminal, and the anterior muscular 
impression behind them. They are found buried deep in the sand, 
in a perpendicular position, their situation being pointed out by a 
dimple, on the surface. They are abundant in temperate climates. 
Some of the Lamarckian Solenes will be found in the genus Solen- 
ocurtus, Bl. Fig. 60, 61. 
SOLENACEA. Lam. A familyof the order Conchifera, Dimyaria 
Lam. The shells belonging to it are described as transversely 
elongated, destitute of accessary pieces, gaping only at the late- 
ral extremities ; ligament external. — The genera may be thus 
distinguished. 

1. Solen. Razor shells, truncated at the extremities. Fig. 60. 

2. Panop^ea. Broad, with prominent tooth. Fig. 65, 66. 

3. Solenocurtus. Rounded at the extremities, with internal 

bar. Fig. 61. 

4. Solenimya. No teeth, epidermis over-reaching the shell. 

Fig. 68. 

5. Glycimeris. Thick, fulcrum of the ligament prominent. 

Fig. 67. 

6. Lepton. Flat, scale-shaped. Fig. 62. 

7. Novaculina. Umbones nearly central; covered by a thin 

epidermis. Fig. 63. 

8. Glauconome. Oval, margins close. Fig. 64. 
SOLENELLA. Sow. (Solen.) Fam. Arcacea, Lam. — Bescr. Oval, 

equi valve, subequilateral, compressed, covered with a thin, shining, 
olive-green epidermis ; hinge with three or four anterior, and 
numerous sharp posterior lateral teeth, arranged in a straight line ; 
muscular impressions two, lateral ; palleal impression with a 
large sinus ; ligament external, prominent, elongated. — Obs. 
This genus partakes of the characters of the genus Nucula, and 
of the family Solenacea. A few specimens of the only species 



262 SPH^ERULACEA. 

known (S. Norrisii, fig. 138.) were dredged by Mr. Cuming at 
Valparaiso. 

SOLENIMYA. Lam. (Solen and Mya.) Fam. Mactracea, Lau. 
Pyloridea, Bl. — Descr. Equivalve, inequilateral, transversely 
oblong, rounded at the extremities with theumbones near the pos- 
terior side, covered with a shining brown epidermis extending 
beyond the edges of the shell ; hinge without teeth ; ligament 
partly internal, placed in the margin of an oblique, flattish, pos- 
terior rib ; muscular impressions two, distant, lateral. From 
the Mediterranean, Australian, and Atlantic Oceans. —Obs. So- 
lenimya differs from Solenocurtus and the true Solens, in having 
the posterior side of the shell the shortest ; in the internal liga- 
ment ; and in being destitute of teeth. It resembles Glyci- 
meris, but is not incrassated. Fig. 68, Solenimya radiata. 

SOLENOCURTUS. Bl. {Solen and curtus, short.) Fam. Pylo- 
ridea, Bl. Solenacea, Lam. — Descr. Oval, elongated, equivalve, 
sub-equilateral, with the edges nearly straight and parallel, and 
the extremities rather truncated ; umbones not very prominent, 
sub-central ; hinge with or without two or three rudimentary 
cardinal teeth ; ligament prominent, placed upon thick callosities ; 
muscular impressions two, distant, rounded ; palleal impression 
straight, with a deep sinus. East Indies — Obs. Distinguished 
from the true Solenes by the central position of the umbones 
and an internal bar reaching partly across the shell. 

SOLETELLINA. Bl. Sanguinolaria radiata. S. Diphos, f. 99. 
S. livida of Sowerby, and similar species, are placed together in 
this genus. 

SPATHA. Lea. A sub-genus of Iridin^e, consisting of I. rubens and 
I. nilotica, which have not distinctly crenulated margins. Spatha 
solenoides, of Lea, is the genus Mycetopus D'Orbigny. Fig. 151, 

SPHiENIA. Turt. A genus consisting of a small species resem- 
bling Saxicava, in general appearance, but having a spoon-shaped 
process on the hinge of one valve. S. Binghamii, Fig. 96. 

SPHiEROIDINA. D'Orb. A genus of microscopic Foraminifera. 

SPH^ERULACEA. Bl. The first family of Cellulacea consisting 
of the following genera of microscopic Foraminifera : Miliola, 
Melonia, Saracenaria, Textularia. 



SPIRIFER. 263 

SPILERULACEA. Lam. The fourth family of Cephalopoda, Lam. 
described as multilocular, globular, sphserical, or oval, with the 
whorls enveloping each other; some of them have a particular in- 
ternal cavity, and are composed of a series of elongated, straight 
and contiguous chambers which altogether form a covering for 
the internal cavity. This family contains the genera Miliola, 
Gyrogona and Melonia. 

SPH^RULITES. Lam. (Sphcera, a sphere) Fam. Rudistes, 
Lam. and Bl. —Beacr. Orbicular, inequivalve, irregularly foliated 
outside ; lower valve cup-shaped, depressed ; upper valve nearly 
flat, like an operculum. — Ohs. These fossils are not regarded as 
shells by all conchologists. S. foliacea, Fig. 193. 

SPHINCTERULUS. Montf. Lenticulina, Bl. A genus of micro- 
scopic Foraminifera. 

SPINES. (Spina, a thorn.) Thin, pointed spikes. 

SPINOSE. (Spinosus.) Having spines or elevated points, as 
Neritina spinosa. Fig. 325. 

SPIRAL. (Spira, a spire.) Revolving outwards from a central 
apex or nucleus, like the spring of a watch. A shell or an 
operculum, may be spiral, without being produced into a pyramid. 
Bands of colour, striae, grooves, &c. commencing from the nucleus 
and following the volutions of the shell, are described by the 
above word. 

SPIRAMILLA. Bl. A genus of Serpulacea, differing from other 
Serpulse principally in the characters of the animal. 

SPIRATELLA. Bl. Limacinea, Lam. Fig. 224. 

SPIRE. (Spira.) The cone or pyramid produced in a non- 
symmetrical univalve by its oblique revolution downwards from 
the apex or nucleus. The spire, in descriptions, includes all 
the volutions above the aperture. See Introduction. 

SPIRIFER. Sow. (Spira, a spire ; fero, to bear.) Order, Bra- 
chiopoda, Lam. — Descr. Transverse, equilateral ; hinge linear, 
straight, widely extended on both sides of the umbones, which 
are separated by a flat area in the upper and larger valve ; this 
area is divided in the centre by a triangular pit for the passage 
of the byssus ; interior with two spirally convolute appendages, 



264 



SPONDYLTJS. 



— Obs. This genus, which is only known in a fossil state, is 
distinguished from Terebratula externally, by the flat area in one 
valve, internally, by the singular spiral process from which the 
above name is derived. Fig. 214, 215. Most of the species be- 
long to the mountain or carboniferous limestone. 

SPIROGLYPHUS. Daud. A genus consisting of a species of 
Serpula Auct. which makes a groove for itself in the surface of 
shells. Serpula spirorbis, var. Dillwyn. Fig. 8. 

SPIROLINA. Lam. A genus of microscopic Foraminifera. 

SPIROLOCULINA. D'Orb. A genus of microscopic Foraminifera. 

SPIRORBIS. Lam. A genus composed of species of Serpula, 
Auct. which are coiled round in a spiral disc like a snake at rest. 
S. nautiloides, fig. 5, is the common little white shell, found upon 
the shell of lobsters. 

SPIRULA. (Spira, a winding compass.) Fam. Lituolata, Lam. 
Lituacea, Bl. — Descr. Convolute, smooth, symmetrical, discoid, 
with parallel unconnected whorls, divided into numerous cham- 
bers by transverse septa ; siphon continuous. — Obs. This 
pretty little shell is partly internal, only a part of it being visible 
when on the animal. Fig. 471. 

SPISULA. Gray. A genus composed of Mactra fragilis, and 
other similar species, which have the ligament sub-external, mar- 
ginal, not separate from the cartilage ; with the posterior lateral 
teeth double in one valve, and single in the other. M. fragilis, 
fig. 80, is the species figured for Spisula in Mr. Gray's paper on 
the Mactradse, in the second series of Loudon's Magazine of 
Natural History. We have since learned, however, that it was 
figured there by mistake, not having been intended for a Spisula, 
but belonging more properly to the genus Mactra, as defined 
by Mr. Gray, whose description of Spisula, is as follows : — 
"Shell ovate, trigonal, sub-angular at each end. Hinge and 
lateral teeth as in Mactra, but hinge of left tooth small. Sipho- 
nal inflexion ovate." The principal difference between Spisula 
and Mactra is, that the ligament is not separated from the 
cartilage in the former. 

SPONDYLUS. Auct. (A sfalt-Jish, Ancients.) Fam. Pectenides, 



STOMATIA. 



265 



Lam. Sub-ostracea, Bl. — Descr. Inequivalve, sub-equilateral, 
irregularly foliaceous and spinose, auriculated, denticulated at 
the margins, attached by the lower and deeper valve ; hinge 
rectilinear, with two prominent teeth in each valve, locking into 
corresponding cavities in the opposite valve ; umbones separated 
by a broad, elongated, triangular disc in the lower valve ; liga- 
ment contained in a groove, dividing the triangular area in the 
centre ; muscular impressions one in each valve, sub-central, 
sub -orbicular. The Mediterranean, East and West Indies, and 
China, produce Spondyli most abundantly. — Obs. This genus is 
remarkable for the richness and beauty of the spines and foliations, 
which adorn the external surface of most of the species, the 
splendid colours by which many of them are varied, and the 
natural groupings formed by their attachment to each other. 
Fig. 177, and Frontispiece. 

SPORULUS. Montf. A genus of microscopic Foraminifera. 

SQUAMOSE. (Squama, a scale.) Scaly, covered with scales, as the 
pedicle of Pollicipes Mitellus, fig. 37*. 

STENOPUS. Guild. (Utevoq, narrow, -rrovc, foot.) A genus nearly 
" allied to the Linnsean Helices, from all of which it differs in 
the curious contraction of the pedal disc, and the caudal tentacu- 
lum furnished with a gland beneath/' The shell is described as 
heliciform, umbilicated, transparent, with the aperture transverse. 
The two species described are Stenopus cruentatus and lividus ; 
they are both from the Caribbean Islands, Guild. Zool. Journ. 
xii. p. 528, tab. 15, f. I to 5. 

STOMATELLA. Lam. See Stomatia. 

STOMATIA. Auct. (oro/m, stoma, mouth.) Fam. Macrostomata, 
Lam. — Descr. Sub-orbicular, oblong, auriform, variegated without, 
iridescent within ; spire depressed ; aperture entire, very wide, 
oblique ; peritreme uninterrupted. Obs. This genus is known 
from Haliotis by being destitute of the series of holes ; is distin- 
guished from Sigaretus by the substance of the shell, the latter 
being internal, and never pearly. Our description includes 
Stomatella, Lam. The Stomatise are marine, and belong to 
the East Indies and New Holland. Fig. 335, S. Phyraotis. 



266 STROPHOSTOMA. 

STORILLUS. Montf. 1, 131. A genus of microscopic Foraminifera, 
included in the genus Rotalites in M. De Blainville's system. 

STRAPAROLLUS. Mont. A genus containing some species of 
Helix, Auct. Generic characters not defined. 

STREPTAXIS. Gray. Fam. Colimacea, Lam.— Descr. Ovate, or 
oblong ; when young, sub-hemispherical, deeply umbilicated, with 
rapidly enlarging whorls. At length the penultimate whorl is 
bent towards the right and dorsal side of the axis, and the 
umbilicus becomes depressed, and often nearly closed. The 
mouth is lunulate, the edge slightly thickened and reflected, and 
often with a single tooth on the outer side of the inner lip. — 
Obs. This genus of land shells is separated from Helix on account 
of the eccentricity of the penultimate whorl. S. contusa, fig. 269. 

STRIATED. (Stria, a groove.) Marked with fine grooves or lines. 

STRIGOCEPHALUS. Defr. Pentamerus, Sow. ? Gypidia, Pal- 
man. 

STROMBUS. Auct. Fam. Alatse, Lam. Angiostomata, Bl. — Descr. 
Oblong, turrited, rather ventricose, solid ; aperture generally 
lengthened, terminating posteriorly in a short canal, and anteri- 
orly in an emargination or truncated canal ; outer lip, when 
young, thin, ; when full grown, thickened and expanded, lobed 
at the spiral extremity, sinuated anteriorly near the caudal canal. 
— Obs. This well known genus includes some species of immense 
size, commonly called conch shells. Most of the recent species 
are brought from the Indian Ocean. Very few fossil species are 
known. The young shells have very much the appearance of 
cones, the outer lips being thin. There are also several species 
which do not, even when full grown, thicken their outer lips very 
considerably. The genus Strombus is distinguished from Ros- 
tellaria, by the notch in the outer lip, which in the latter genus is 
close to the canal. Fig. 406, S. pugilis. 

STROPHOMENA. Rafinesque. Orthis, Dalman. 

STROPHOSTOMA. Deshayes. A fossil shell, of the family of 
Colimacea, Lam. in some degree resembling Anostoma, having 
the aperture turned upwards towards the spire, it is, however, 
umbilicated, and is said to have an operculum resembling 



SUB-MYTILACEA. 267 

that of Cyclostoma. It is the Ferussina of Grateloup. Fig. 
534, 5, 6. 
STRUTHIOLARIA. Auct. (Struthio, an Ostrich.) Fam. Canali- 
fera, Lam.— Descr. Oblong, turrited, thick ; spire turrited, 
composed of several angulated whorls ; aperture oval, sub-quad- 
rate,oblique; outer lip thickeDed, reflected, advancing in the centre, 
receding towards the extremities ; inner lip thickened, expanded 
over the columella and part of the body whorl. — Obs. This singular 
genus, consisting of three or four recent species, is named "Pied 
D'Autruche" by the French, on account of some resemblance in 
the outer lip to the foot of the Ostrich. From New Zealand. Fig. 
391, S. straminea. 

STYLIFER. Brod. (Stylus, a style ; fero, to bear.)— Descr. 
Thin, pellucid, turbinated ; apex a little out of the perpendicular; 
aperture wide anteriorly, gradually narrowing towards the spiral 
extremity, where it terminates acutely. — Obs. This is a genus of 
small, transparent shells, found burrowing in the rays of Starfish. 
There are but two or three species at present known, one of 
which is elongated like Terebra, the other nearly globular. Fig. 
12, S. astericola. West Indies, Gallapagos, and Britain. 

STYLINA. Flem. Stylifer, Brod. 

SUB. {under.) Used as a prefix and signifying nearly. Thus a 
bivalve-shell, the valves of which are nearly alike, would be de- 
scribed as sw&-equivalve. 

SUB-APLYSIACEA. Bl. The first family of the order Mono- 
pleurobranchiata, Bl. containing several genera of Mollusca without 
shells, and the genus Pleurobranchus. 

SUB-BIVALVES. A term of distinction applied by De Blainville, 
to those spiral univalves which have an operculum ; these, as 
they constitute two distinct pieces, he considers as forming a 
medium between univalves and bivalves. 

SUB-MYTILACEA. BL The sixth family of the order Lamelli- 
branchiata, Bl. the shells belonging to which are described as 
free, rather pearly, regular, equivalve ; hinge dorsal, laminated ; 
ligament external ; two muscular impressions; palleal impresion 
not sinuated. This family, with the exception of the last genus, 



268 SUTURE. 

agrees with the family Nayades of Lamarck, and contains the 
genera Anodon, Unio, and Cardita. 

SUB-OSTRACEA. Bl. The second family of Lamellibranchiata, 
Bl. the shells of which are described as of a compact texture, 
sub-symmetrical; with the hinge rather complex; one single, 
sub-central, muscular impression, without any traces of pal- 
leal impression. This family corresponds with the Pectenides 
of Lamarck, and part of the genus Ostrea in the system of Lin- 
nseus. It contains the genera Spondylus, Plicatula, Hinnites, 
Pecten, Pedum, Lima. 

SUB-SPIRAL. Not sufficiently spiral to form a complete volution. 

SUBULA. Bl. (An awl.) A generic name under which M. De 
Blainville includes Terebra maculata, Auct. f. 428, together 
with nearly all the species of Terebra, enumerated by Lamarck 
and other authors ; only leaving in the latter genus those species, 
which being more bulbous, or ventricose, nearly resemble Bucci- 
num in general form. These last mentioned species, such as 
Terebra buccinoidea, (fig. 247) have been formed into a new 
genus by Mr. Gray, under the name Bullia. If both these genera 
were adopted, the genus Terebra would be extinct. 

SUBULATE. (Subula, an awl.) A term applied to shells which 
are long and pointed as in Terebra/ Fig. 427, 428. 

SUCCINEA. Drap. (Succinum, amber.) Fam. Colimacea, Lam. 
Limacinea, Bl. Sub-genus, Cochlohydra, Fer. — Descr. Ovate, 
rather elongated ; aperture large, entire, longitudinal ; spire 
short ; outer lip thin, continuous with the thin, sharp-edged co- 
lumella ; inner lip spread over a part of the body-whorl. — Obs. 
The shells belonging to this genus of partly amphibious mollusca, 
are distinguished from Limnaea by not having a fold on the 
columella. The S. amphibia is of a bright amber colour. Fig. 
265, 266. Temperate and tropical climates. 

SULCATED. (Sulcatus, lat.) Having grooves or furrows. 

SULCI. Grooves or furrows. 

SUTURE. (Sutura, lat.) A seam, stitch, joining together. Ap- 
plied particularly to the line which marks the joining of the 
whorls of the spire. The suture is distinguished as simple, as in 



TELLINA. 



269 



most cases ; or double, when accompanied by a parallel groove 
close to it ; marginated, when produced into a ledge by the mat- 
ter which fills up and covers it ; obsolete, when it is filled up so 
as not to be visible, as in the case of Ancillaria. 
SYLVICOLA. Humph. Cyclostoma, Lam. 
SYMMETRICAL, {aw, syn, similar ; jxerpov, metron, proportion.) 
Both sides alike. Although the term is used thus as one of dis- 
tinction, it is to be observed that no shells are strictly and per- 
fectly symmetrical ; even in the Nautilus, the apex verges in a 
slight degree towards one side of the shell. Two kinds of uni- 
valve are symmetrical, or nearly so; 1st. Those which are sym- 
metrically convolute, as the Nautilacea and the Ammonacea, 
which are spiral ; 2nd. Those which are not spiral, but simply 
conical, as the patelliform shells. Bivalves belonging to the 
Brachiopoda are also symmetrical. Ex. Patella, fig. 229. Ammo- 
nites, fig. 478. 
SYMPHYNOTA. Lea. A genus of Nayades, in which Mr. Lea 
proposed to include species of the genus Unio, the valves of 
which are connate, or united at the dorsal margin. We believe 
that this distinction, as a genus, has been abandoned by its author. 
The fact is, that all the Uniones are Symphynotse when in a 
young state. In Unio Alatus, (fig. 147) and Dipsas plicatus, 
(fig. 142) it will be observed that the valves have not separated 
at the dorsal edge, but are broken lower down. 
TAP ADA. (Gray. Turton. p. 127.) A division of the genus He- 
lix, containing Helix aperta, Auct. or the Tapada snail. 
TAPES. Schum. Pullastra. Sow. ? 

TECTUS. Montf. A genus composed of species of the genus 

Trochus, having elevated, conical spires, and columella notched 

or truncated by a spiral fold. Fig. 359. Trochus maculatus, 

presents an example. 

TELEBOIS. Montf. A genus of microscopic Foraminifera. 

TELESCOPIUM. Montf. Cerithium Telescopium, Auct. fig. 

378. 
TELLINA. Linn. Fam. Nymphacea, Lam. Conchacea, Bl. — 



2/0 TEREBELLUM. 

Descr. Sub-equivalve, inequilateral, compressed, rounded ante- 
riorly, slightly beaked or angulated posteriorly, the posterior 
ventral margin having a flexuosity ; hinge with two cardinal and 
generally two lateral teeth in each valve; muscular impres- 
sions, two in each valve, remote ; palleal impression with a large 
sinus. — Obs. The fold or bending in the posterior margin dis- 
tinguishes this genus from others which it nearly resembles. It 
is composed of some bivalves of great beauty and variety, which 
are found in nearly all climates. Fig. 105, T. radiata, 106, T. 
lingua -felis. 

TELLINIDES. Lam. Fam. Nymphacea, Lam. — Descr. Sub-equi- 
valve, inequilateral, transverse, compressed, rounded anteriorly, 
slightly beaked or angulated posteriorly ; hinge with two cardinal 
teeth in each valve, and one lateral tooth in one valve, very near 
the cardinal teeth, Muscular impressions two, distant, palleal 
impression with a large sinus. Obs. This genus is distinguished 
from Tellina in having but one lateral tooth nearthe cardinal teeth. 
Fig. 107, T. rosea. Tropical. 

TENUIPEDES. (Tenuis, slender; pedes, feet.) The second sec- 
tion of the order Conchifera Dimyaria, divided into the families 
Mactracea, Corbulacea, Lithophagidse, Nymphacea. 

TERACLITA. Schum. Conia, Auct. 

TEREBELLUM. Lam. ( Terebra, an augur ?) Fam. Convolutse, 
Lam. Angyostomata, Bl. — Descr. Smooth, slender, oblong, sub- 
cylindrical ; spire obtuse, short, sometimes hidden; (Seraphs, 
Montf.) aperture long, narrow posteriorly, wider anteriorly ; outer 
lip slightly thickened, truncated, unconnected at the base with 
the columella ; inner lip thin, smooth, nearly straight, spread 
over a portion of the body -whorl, continued in a ridge above the 
sutures of the spire. — Obs. Montfort has separated the fossil 
species with hidden spires, under the name Seraphs. (T. convo- 
lutum, Lam.) Only one recent species is known, of which there 
are several varieties, one spotted, one marked in sub-spiral lines, 
another in patches. It is brought from the East Indies. Fig. 451, 
T. convolutum ; 452, T. subulatum. 



TEREBRATULA. 271 

TEREBRA. (An augur, a piercer.) Fam. Purpurifera, Lam. Ento- 
mostomata, Bl. — Descr. Subulate, elongated, pointed, turrited ; 
spire long, consisting of numerous whorls; aperture small ter- 
minating in a short, reflected canal ; outer lip thin ; columella 
tortuous; operculum horny. The recent species are mostly 
tropical.— Obs. Nearly all the species enumerated by Lamarck 
and other authors are included by De Blainville in his genus 
Subula ; those few species which that conchologist left in 
the present genus, being shorter and more ventricose than 
the others, approximate in shape to some of the Buccina, 
and are distinguished by Mr. Gray under the generic name 
Bullia. It seems strange, that De Blainville, being convinced of 
the necessity of separating the two groups, and consequently 
applying a new generic term to one of them, should have given 
that term to the larger number and the more typical species of 
the Lamarckian genus. Fig. 427, Bullia vittata. (Terebra.) Fig. 
428, Terebra maculata. (Subula.) 

TEREBRALIA. Sw. A genus of " Cerithinae," Sw. thus de- 
scribed : ' ' Outer lip much dilated, generally uniting at its base 
to the inner lip ; leaving a round perforation at the base of the 
pillar ; channel truncate ; operculum round : palustre. Mart. f. 
1472." Sw. p. 315. 

TEREBRATING SHELLS. (Terebro, to pierce.) Shells which 
reside in holes pierced in rocks, wood, &c. by means of some 
corrosive secretion of the animal. Ex. Pholas, Teredo, &c. 

TEREBRATULA. Brug. (Terebratus, bored.) Fam. Brachio- 
poda, Lam. — Order. Palliobranchiata, Bl. — Descr. Inequivalve, 
equilateral, oval or sub-trigonal, ventricose or compressed, at- 
tached by a tendon passing through an opening in the dorsal, or 
upper and larger valve, the umbo of which advances beyond that 
of the other valve ; hinge destitute of a ligament, with two teeth 
in the dorsal valve, locked into corresponding cavities in the ven- 
tral, or lower valve, and with two curious processes originating 
at the umbo of the lower valve, presenting, in some species, the 
appearance of fine winding tape, advancing towards the front of 
the valve, and again receding to the centre, where the ends unite ; 



272 TESTACELLA. 

muscular impressions two, placed near the centre of each valve. — 
Obs. The Terebratulse are included in the genus Anomia in the 
system of Linnaeus. The recent species are not very numerous — 
they are found in all climates. The fossil species are more nu- 
merous than the recent ones, occurring in the secondary and ter- 
tiary formations. T. Psittacea, fig. 202. 

TEREDINA. (From Teredo.) Fam. Tubicolee, Lam. Adesmacea, 
Bl. — Descr. Valves equal, inequilateral, with prominent umbones, 
as it were soldered to the outside of the rounded end of a shelly 
tube, of which they form a part ; aperture of the tube partly 
divided ; a flat accessary valve placed on the umbones. — Obs. 
This genus, which is only known in a fossil state, is distinguished 
from Teredo, by the valves being fixed on the tube, and the tube 
being closed at one extremity. Fig. 46, 47, T. personata. 

TEREDO. Auct. (A piercer.) Fam. Tubicobe, Lam. Adesmacea, 
Bl. — Descr. Valves equal, inequilateral ; presenting when closed, 
an orbicular figure, with a large angular opening in front, and a 
rounded opening at the back ; placed at the anterior extremity of 
an irregular, flexuous, elongated tube, open at both ends ; the 
anterior termination divided in a double aperture opened and 
closed at the will of the animal by two opercula. — Obs. This 
genus of Molluscous Animals, is remarkable for boring holes in 
wood, which are filled by their elongated tubes, and give it a 
honey-comb appearance. Fig. 48. T. Navalis. Fig. 49, apiece of 
bored wood. 

TERMINAL. When the umbones of a bivalve shell are placed at 
or near the extremity, as in Mytilus, fig. 158, Pinna, fig. 162, 
they are said to be terminal. The same term is also applied to 
the nucleus of an operculum, when it forms an extreme point, or 
is close to one of the edges. 

TESSELLATED. (Wrought in chequer-work) A term applied 
to the colouring of shells, when arranged in regular defined patches 
like a tessellated pavement. 

TESTACELLA. (Testa, a shell.) Fam. Limacinea, Lam. and 
Bl. — Descr. Haliotoid, compressed; aperture wide, oblique; 
columella flat, oblique ; spire short, flat, consisting of less than 



THELICONUS. 273 

two whorls.— Obs. This shell which is extremely small compared 
with the animal, is placed upon its back, near the posterior 
extremity. The animal is found in some of our gardens, and 
very much resembles the common garden-slug. Fig. 261, T. 
Haliotoidea. 

TESTACEOUS. {Testa, a shell.) Shelly. Testaceous Mollusca, 
are soft animals having shells. A testaceous operculum is one 
composed of shelly matter. 

TETRACERA. Bl. The first family of the order Polybranchiata, 
Bl. containing no genera of testaceous mollusca. 

TEXTILIA. Sw. A sub-genus of Conus, consisting of Conus 
bullatus, &c. Sw. Malac. p. 312. 

TEXTULARIA. Defr. A genus of microscopic Foraminifera. 

THALAMUS. Montf. A genus described as resembling Conilites, 
but curved and granulated. 

THALLEPUS. Sw. A genus of " Aprysianise," Sw. thus de- 
scribed : "Body more slender and fusiform;" (than Aplysia,) 
"the lobes of the mantle short, and incapable of being used for 
swimming ; tentacula two, large, ear shaped ; eyes not visible. 
T. ornatus, Sw. Sp. Nov." Sw. p. 359. 

THALLICERA. Sw. A generic name under which Swainson 
distinguishes Ampullaria Avellana, Auct. 

THECIDIUM. (Thecas, a box.) Fam. Brachiopoda, Lam. Order, 
Palliobranchiata, Bl. — Bescr. Lower valve concave, sub-trigonal, 
with the umbo produced into a triangular, slightly incurved beak, 
and with two short, pointed processes advancing from beneath 
theumbones ; upper valve flat, rounded square, with a short, 
blunt appendage, formed to fit between the tooth-like process 
of the other valve ; its inner surface ornamented with symmetri- 
cally curved ridges. 

THECOSOMATA. BL The first family of the order Aporobran- 
chiata, Bl. containing the genera Hyalsea, Cleodora, Cymbulia, 
Pyrgo. 

THELICONUS. Sw. A sub-genus of Conus. Lardn. Cyclop. 
Malac. p. 312. 

T 



274 TOMELLA. 

THELIDOMUS. Sw. A generic name under which Swainson has 
described a division of the, genus Helix, and which he has also used 
to designate a genus in the family of " Rotellinse," founded upon 
an aggregate of loose particles collected and agglutinated in a 
spiral form by the larva of an insect. Sw. Malac. p. 330 and 353. 

THEMEON. Montf. A genus of microscopic Foraminifera. 

THEODOXUS. Montf. A division of the genus Nerita. Fig. 324, 
N. virginea. 

THETIS. Sow. (A sea nymph) A genus of fossil shells, de- 
scribed as resembling Mactra, but not having the internal ligament, 
and having several small, acuminated, cardinal teeth, but no lateral 
teeth. It resembles Tellina in some degree, but has not the 
posterior fold. 

THIARELLA. Sw. A sub-genus of Mitra, Lardn. Cyclop. Malac. 
p. 319. 

THRACIA. Leach. Fam. Lithophagidae, Lam. Pyloridea, Bl. 
A genus described as intermediate between Anatina, and Mya, 
and in some degree resembling Corbnla. T. corbuloides, fig. 93. 

THUNDER-STONES. One of the vulgar appellations which have 
been applied to shells of the genus Belemnites. 

THIATYRA. Leach. A genus composed of Amphidesm a flexuosa, 
Lam. and similar species, belonging more properly to the genus 
Lucina. 

TIARA. Sw. A genus of "Mitranse," Sw. thus described: "Aper- 
ture narrow, linear, or of equal breadth throughout ; outer lip 
andbaseof the body whorl contracted, the former generally striated; 
an internal canal at the upper part of the aperture; shell (typically) 
turrited, and equally fusiform ; representing the Muricidce and 
Cymbiola." Sw. Malac. p. 319. The principal differencebetween 
Tiara and Mitra appears to be that in the latter, the aperture is 
more linear and contracted in the centre. Mitra Episcopalis 
s an example. 

TINOPORUS. Montf. A genus of microscopic Foraminifera. 

TIRANITES. Montf. A division of the genus Baculites. 

TOMELLA. Sw. A genus of " Pleurotominre," Sw. thus de- 



TRANSVERSE. 2/5 

scribed: "Fusiform, smooth ; the spire of very few whorls, and 
not longer, than the channel ; inner lip with a thick callosity at 
the top ; the slit short and wide ; lineata, En. Meth. 440, f. 2, 
clavicularis, lb. f. 4. filosa. En. Meth. 440, f. 6. lineolata. lb. 
f. 11." Sw. p. 314. 

TOMOGERUS. Montf. Anastoma, Auct. Fig. 4/1. 

TONICHIA. Gray. Syn. B. M. p. 126. A genus composed of 
those species of Chiton which have the margin smooth. 

TORNATELLA. Auct. Fam. Piicacea, Lam.— Bescr. Oval, spi- 
rally grooved ; spire short, rather obtuse, consisting of few 
whorls ; aperture long, narrow, rounded anteriorly ; outer lip 
simple ; inner lip thin, slightly spread, columella spiral, incras- 
sated, confluent with the outer lip. The recent species are few. 
Several fossil species occur in London Clay, Inferior Oolite and 
Calcaire-grossier. Monoptygma, Lea, resembles this genus, but 
has a fold on the inner lip. Fig. 343, T. solidula. 

TORTUOUS. (Tortuosus) Twisted. This adjective is sometimes 
applied as a specific name ; as Area tortuosa. 

TRACHELIPODA. Lam. (rpa^jAoe, trachelos, a neck ; Tro^a, 
poda, foot.) The third order of the class Mollusca, in the system 
of Lamarck. The trachelipodous mollusca are described as having 
the posterior part of the body spirally twisted and separated from 
the foot ; always enveloped in a shell. The foot is free, flat, 
attached to the base of the neck. Shell spiral, and enclosing the 
animal when at rest. This order contains the families, Coli- 
macea, Lymnacea, Melaniana, Peristomiana, Neritacea, Janthinea, 
Macrostomata, Scalariana, Piicacea, Canalifera, Alata, Purpuri- 
fera, Columellaria, Convolutse. The genera belonging to these 
families, are represented in the plates, fig. 264, to 462. 

TRANSVERSE. (Crosswise.) A shell is said to be transverse, 
when its width is greater than its length, that is, when it is 
longer from one side to the other than from the umbones to the 
ventral margins. The term is applied by some authors to express 
the direction of the lines of growth in bivalve shells, and the 
spiral lines in spiral shells. See Concentric. 

t 2 



276 TRIDACNACEA. 



TRAPEZIUM. Meg. Cypricardia, Lam. 



TRAPEZIFORM, or 

TRAPEZOID. {rpaive'CLov, trapesion, trapezium', sicog, eidos, form.') 
Having four unequal and unparallel sides. Ex. Cucullsea, fig. 
133. 

TRIBULUS. Klein. Ricinula, Lam. 

TRICHOTROPIS. Brod, and Sow. {T P i X oq, trichos, hair ; rpoTrtc, 
tropis, keel.) Fam. Purpurifera, Lam. — Bescr. Turbinated, 
keeled, thin, umbilicated ; aperture longer than the spire, entire j 
columella obliquely truncated ; outer lip thin, sharp ; epidermis 
horny, produced into long hairs at the angles of the shell ; oper- 
culum horny, with the nucleus lateral.— Obs, Although the shells 
of this genus have something of the shape of Turbo, they are 
distinguished from that genus at once by the thinness of the shell. 
They are also known from Buccinum, by the absence of a canal. 
Only two or three species are known, which belong to the Northern 
and Arctic Oceans. T. bicarinata, fig. 429. 

TRIDACNA. Auct. Fam. Tridacnacea, Lam. Chamacea, Bl. — ■ 
Descr. Equivalve, regular, inequilateral, radiately ribbed, adorned 
on the ribs with vaulted foliations, waved at the margins, with a 
large, anterior hiatus close to the umbones, for the passage of a 
large byssus, by which the animal fixes itself to marine substances; 
hinge with a partly external ligament ; two laminar teeth in one 
valve, one in the other. — Obs. The beautiful shells composing 
this genus are of a delicate white colour, tinged with buff. One 
species, theT. gigas, attains a remarkable size, measuring from two 
to three feet across, and weighing five hundred pounds. Tridacna 
is distinguished from Hippopusby the large opening in the hinge. 
T. elongata, fig. 157. 

TRIDACNACEA. Lam. A family belonging to the first section 
of the order Conchifera Dimyaria, Lam. described as regular, 
equivalve, solid, and which are remarkable for the deeply sinuated 
or undulated ventral margin. This family contains the genera : 

1. Hippo pus. Valves closed at or near the hinge. Fig. 156. 

2. Tridacna. An hiatus near the hinge. Fig. 157. 



TRIGONOTRETA. 2/7* 

TRIDENTATE. (Tridentatus.) Having three teeth, or salient 
points. Ex. Hyalsea tridentata, fig. 226. 

TRIGONA. Schum. ? Triangular species of Cytherea, such as C. 
laevigata, Triplas corhicula, ventricosa, bicolor, &c Fig. 117 b. 

TRIGONACEA. Lam. A family belonging to the order Conchi- 
fera Dimyaria, containing the genera Trigonia and Castalia, the 
latter of which ought to be removed to the Nayades. Fig. 
139, 140. 

TRIGONAL. Triangular, having three sides. 

TRIGONELLA. Humph. Mactra, Auct. 

TRIGONIA. Brag, (rpiywvov, trigonon, triangular.) Fam. Tri- 
gonata, Lam. Camacea, BL— Descr. Equivalve, inequilateral, 
transverse, sub-trigonal, costated and granulated without, pearly 
and iridescent within, denticulated on the inner margin, rounded 
anteriorly, truncated posteriorly ; hinge with four oblong, com- 
. pressed, diverging teeth in one valve, receiving between their 
grooved sides, two similar teeth in the other ; ligament external, 
thick ; muscular impressions two in each valve. — Obs. Only one 
recent species of this marine genus is known, the T. pectinata, 
which comes from New Holland ; and was formerly so rare, that a 
much worn odd valve has been sold for a considerable sum. It is of 
a brilliant pearly texture within, tinged with purple or golden 
brown. Fossil species occur in Lias, upper and lower Oolite, 
and Green-sand. T. Pectinata, fig. 139. 

TRIGONOSEMUS. Konig. A genus composed of* species of 
Terebratula, Auct. which have one valve produced into a beak, 
perforated, or as it were truncated at the apex. T. lyra, fig. 208, 
differing from Terebratula lyra, Lam. 

TRIGONOSTOMA . A sub-genus of Helix, with a trigonal aperture. 
Gray's Turton, p. 139. 

TRIGONOTRETA. Konig. A genus composed of species of 
Terebratula, Auct. which have the hinge of the larger valve pro- 
duced into a triangular disc, divided by a triangular foramen in 
the centre. Spirifer, Sowerby, belongs to this genus. Fig. 
214, 215. 



27S TRITON. 

TRILOBATE. (Tp«c, three ; \opog, division, lobe.) Divided into 
three lobes or principal parts. Ex. Malleus, Fig. 165. 

TRILOCULINA. D'Orbigny. A genus of microscopic Foraminifera. 

TRIPARTITE. (Tripartitus) composed of or divided into three 
separate parts. 

TRIPHORA, or TRISTOMA. Deshayes. A genus composed of 
small reversed species of Cerithium, Auet. which have the an- 
terior canal closed at the anterior of the aperture, but opened at 
the extremity, and a small tubular opening on the upper part of 
the whorls, making three openings on the body whorl. This 
genus stands in the same relation to Cerithium as the Typhis to 
Murex. Fig. 375 in the old plates, and fig. in the new plates. 

TRIPLEX. Humph. Murex, Linn. 

TRIPLODON. Spix. Hyria, Auct. 

TRIPTERA. Quoy et Gaimard, Cuviera, Fer. Described in the 
Voyage de la Coquille, and represented as a molluscous animal 
destitute of a shell. 

TRIQUETRA. Bl. Triangular species of Venus, Auct. 

TRISIS. Oken. Arca tortuosa, Auct. 

TRISTOMA. Described as Triphora. 

TRITON. Auct. Fam. Siphonostomata, Bl. Canalifera, Lam.— 
Descr. Oblong or oval, thick, ribbed or tuberculated, with discon- 
tinuous varices placed at irregular distances ; spire prominent, 
mammillated; aperture round or oval, terminating anteriorly in a 
generally long, slightly raised canal ; columellar lip granulated or 
denticulated; outer lip thickened, reflected, generally denticulated 
within; epidermis rough; operculum horny. — Obs. However 
nearly allied the Tritons may appear to be to the Murices and 
Ranellee there are still to be traced in the shells of each of those 
genera, several constant and well marked distinctions, by which they 
maybe at once recognized. In the Ranellee, the varices run in 
two rows along the spire ; in the Murices, they form three or more 
rows; but in the Tritons, they do not follow each other, i. e. they 
do not occur in the same part of each volution. The large species 
of Triton, are sometimes used as trumpets. The Tritons are 



troche. 279 

brought from the Mediterranean, Ceylon, the East and West 
Indies, and South Seas. Fig. 398 to 401. 

TRITONIDEA. Sw. A genus of "BuccininEe," Sw. thus de- 
scribed : " Shell bucciniform, but the basal half is narrowed, 
and the middle more or less ventricose ; spire and aperture equal. 
Pillar at the base with two or three obtuse and very transverse 
plaits, not well defined ; outer lip internally crenated and with 
a superior siphon ; inner lip wanting, or rudimentary." This 
genus is the same as the one first distinguished by Mr. Gray 
under the name of Pollia. We do not regret the discovery made 
by Mr. Swainson of that name being previously occupied for a 

. genus of Lepidopterous Insects. Fig. 415, represents Tritonidea 
articularis. (Pollia, Gray.) 

TRIVIA. Gray. A genus composed of those small species of 
Cyprus a, Auct. which are characterized by small ridges on 
the dorsal surface, and have the anterior of the columella inter- 
nally concave and ribbed. C. Pediculus. Auct. fig. 449, 450. 

TROCHATELLA. Sw. A sub-genus of Helicinse, consisting of 
those species which are acute and trochiform. 

TROCHIA. Sw. A genus of the family Buccinime, thus described : 
" shape intermediate between Purpura and Buccinum ; whorls 
separated by a deep groove ; inner lip when young, depressed, 
when adult, thickened, convex and striated ; basal canal very 
small. T. sulcatus. E. M. 422. f. 4." Sw. Malac. p. 300. 

TROCHIDON. Sw. A sub-genus of X Trochinse," Sw. Lardn. 
Cyclop. Malac. p. 351. 

TROCHIL^EA. Sw. ? Pileoltjs, Auct. 

TROCHURUS. Humph. Monodonta. Lam. 

TROCHUS. Auct. {A top.) Fain. Turbinacea, Lam. Goniosto- 
mata, BL — Descr. Turbinated, thick, striated, tuberculated or 
smooth ; spire elevated, conical, consisting of numerous whorls ; 
under surface discoid ; aperture more or less depressed in an oblique 
direction, generally angular ; columella arcuated, more or less 
prominent at its union with the outer lip, contiguous to the 
axis of the shell ; operculum horny, orbicular, with numerous 
whorls. — Obs. Lamarck distinguished this genus from Turbo by 



280 TUBICINELLA. 

the general form, which is more conical, and the aperture, which 
is angulated, while that of Turbo is rounded. Monodonta or 
Odontis is only separated on account of the notch at the ter- 
mination of the columella. But these characters glide so imper- 
ceptibly from one genus to the other, that there is no line of de- 
marcation to be found but in the operculum. Accordingly, 
Sowerby (in Gen. of Sh. 37.) has stated his reasons for 
considering as Trochi, all the species which have horny opercula ; 
and as Turbines, all those which have testaceous opercula. Fig. 
358 to 360. The Trochi are found in all climates. 
TROP^EUM. Sow. Crioceratites. 

TROPHON. Montf. Murex Magellanicus, Auct. and several 
other species which belong more properly to Fusus than to 
Murex. 

TRUMPET SHELL. A large species of Triton (variegatus), used 
by natives of South Sea Islands as a trumpet, to call warriors 
and herds of cattle together. It answers the purpose tolerably 
well, producing a very sonorous blast. 

TRUNCATED, (truncus, cut short.) Terminating abruptly, as it 
were cut short. Ex. Solenensis, fig. 60. 

TRUNCATULANA. D'Orb. A genus of microscopic Foraminifera. 

TRUNCATELLA. Risso. A genus composed of several species 
of land shells which have been confounded by some authors with 
Cyclostoma. The genus is thus described : " Shell turriculated, 
cylindrical, decollated or truncated at the apex, no epidermis ; 
aperture oval, short, with lips continuous, simple." Ifo. Truncatella 
truncatulina, Lowe, Zool. Journ. t. 5. p. 80. Our plates, 
fig. 520, 521. It is found on the shores of Britain, the Mediter- 
ranean, and West Indies. 

TUBA. Lea. A genus of small fossil shells, described as resem- 
bling Turbo, but with the aperture more like that of Melania. Lea. 
Contrib. Geol. 

TUBERCLE, (tuberculus.) A small swelling excrescence, or knob. 

TUBERCULATED. Having a number of small lumps or pimples, 
as Turriiites, fig. 483. 

TUBICINELLA. Lam. (Tubicen, a trumpeter.) Order, Sessile 



TURB1NACEA. 281 

Cirripedes, Lam. — Descr. A cylindrical tube, composed of six 
elongated valves jointed together side by side, striated longitudi- 
nally, surrounded by concentric rings ; aperture circular, enclosed 
by an operculum of four valves, placed perpendicularly in an 
epiphragm. — Obs. The Tubicinellse are found with nearly the 
whole shell buried in the thick skin of the whale. T. Balgenarum. 
TUBICOLARIA. Lam. ( 1 \iba, a tube ; cola, an inhabitant.) A 
family of the order Conchifera Dimyaria, Lam. consisting of 
bivalves soldered as it were within, or connected with, a testa- 
ceous tube. The genera contained in this family may be thus 
distinguished. 

1. Aspergillus!. Valves fixed, tube perforated and fringed. 

Fig. 44. 

2. Teredina. Valves fixed, prominent, tube closed at one 

end. Fossil. Fig. 46, 47. 

3. Clavagella. One valve fixed, the other free. Fig. 45. 

4. Teredo. Both valves free, tube open at both ends. 

Fig. 48, 49. 

5. Fistulana. Valves free, tube closed at one end, straight, 

long. Fig. 53, 54. 
6*. Gastroch^ena. Valves free, tube closed at one end, short, 
bulbous. Fig. 52. 
TUB1VALVES. Bl. Shells composed of two valves connected in 

a tube, corresponding with the family Tubicolse of Lamarck. 
TULIPARJA. Sw. A sub-genus of " Coronaxis," Sw. Lardn. 

Cyclop. Malac. p. 311. 
TURBINACEA. Bl. The sixth family of Poly thalamacea, Bl. con- 
taining the genera Cibicides and Rosallites, microscopic Forami- 
nifera. 
TURBINACEA. Lam. A family of the first section of the order 
Trachelipoda, Lam. containing the following genera. 

1. Solarium. With umbilicus reaching to the apex ; includ- 

ing Bifrontia and Orbis. Fig. 353 to 356. 

2. Rotella. A callosity on the underside. Fig. 357. 

3. Phasianella. Oval; operculum shelly. Fig. 367. 

4. Planaxis. Columellar lip flat; aperture notched. Fig. 365. 



282 TURBO. 

5. Turbo. Top-shaped; mouth generally round ; operculum 

shelly. Fig. 368. 

6. Trochus. Top-shaped ; mo-nth generally angulated ; oper- 

culum horny, consisting of many whorls ; including Elen- 
chus. Fig. 358,359, 361. 

7. Margarita. Operculum horny, consisting of few whorls; 

pearly. Fig. 362, 

8. Littorina. Similar, not pearly ; including Assiminea. Fig. 

363, 363*. 

9. Phorus. Attaching dead shells, stones, &c. Fig. 360. 

10. Monodonta or Odontis. A notch and prominent point 

at the lower part of the aperture. Fig. 366. 

11. Lacuna. With an umbilicus. Fig. 364. 

12 Turritella. Elongated, screw-shaped. Fig. 369 to 371. 

TURBINATED. (Turbo, atop,) Top-shaped. The term is applied 
generally to those shells which are large at one extremity, and 
narrow to a point at the other. Ex. Trochus, fig. 358 ; Turbi- 
nellus, fig. 382. 

TURBINELLUS. Auct. (A little top.) Fam. Canalifera, Lam. 
Siphonostomata, Bl. — Descr. Turbinated, thick, wide near the 
apex, generally tuberculated ; spire short, depressed, mammil- 
lated ; aperture rather narrow, terminating anteriorly in an open 
canal; outer lip thickened within ; columella having from three 
to five prominent, compressed, transverse folds. The species of 
this genus are mostly tropical, — Obs. The Turbinelli are a well 
marked genus of marine shells, the species of which are numerous. 
No fossil species are known. The genus Cancellaria makes the 
nearest approach to Turbinellus in some characters, but may be 
distinguished by the roundness of its form, the raised lines inside 
the outer lip, and the obliquity of the folds on the columella. 
Fig. 382 to 384. 

TURBO. Auct. (A top.) Fam. Cricostomata, Bl. Turbinacea, 
Lam. — Descr. Turbinated, solid, ventricose, generally grooved of 
tuberculated ; spire short, pointed ; aperture generally rounded, 
sub-effuse anteriorly, entire; operculum shelly, solid, incrassated 
on the outer side, horny and sub-spiral on the inner side. The 



TYMPANOSTOMA. 283 

Turbines are mostly tropical. — Obs. The only certain means of 
distinguishing this extensive genus of marine shells from Trochus, 
is the operculum, which in the latter genus is horny, spiral, 
and composed of a great number of whorls. The Trochi, however, 
are in general more conical, and flatter at the under side of the 
whorls, and this constitutes Lamarck's distinction between the 
genera. T. setosus, fig. 368. 

TURGID. (Turgidus.) Puffed up, swollen, inflated. This term 
is applied synonymously with Ventricose. 

TURRICULA. Humph. Melania, Auct. 

TURRICULACEA. Bl. The seventh family of the Order Poly- 
thalamacea, Bl. containing the genus Turrilites, fig. 483. 

TURRILITES. Lam. (Turris, a tower; Xtdog, a stone.) Fam. 
Turriculacea, Lam. Ammonacea, Bl. — Descr. Chambered, turrited, 
spiral ; septa sinuous and lobate, perforated by a siphon ; aper- 
ture rounded, with the outer lip expanded. This genus, which is 
distinguished from the other Ammonacea by having the spire 
produced, i. e. not being convolute, consists of several species, 
occurring only in chalk-marl. Fig. 483. 

TURRIS. Montf. A genus composed of those species of Mitra, 
Auct. which have the whorls angulated, with the aperture length- 
ened and undulated. 

TURRITED. The spire of an univalve shell is said to be turrited 
when the whorls of which it is composed are regulated so as to 
have the appearance of little turrets rising above each other, as 
in Mitra, fig. 431. 

TURRITELLA. Lam. {A little tower.) Fam. Turbinacea, Lam. 
Cricostomata, Bl. — Descr. Turrited, elongated, generally grooved 
spirally ; spire pointed, consisting of numerous whorls ; aperture 
rounded or angulated ; inner and outer lips thin, confluent 
anteriorly; operculum horny. — Obs. The shells composing this 
well defined genus, are commonly called screws, a name to which 
the spiral grooves of most of the species seems to entitle them. 
Fig. 3/0, T. imbricata. 

TYMPANOSTOMA. Schum. (Timbrel mouth.) Potamis, Brongn. 



284 UNDATED. 

TYPHIS. Montf. A genus composed of Murex tubifer, Auct. 
and other similar species, which have the canal closed and a 
perforated tube between each varix on the angulated part of the 
whorls. Besides the fossil species originally described, there are 
now five species known, which are figured in part 200, of the 
Conchological Illustrations by the Author. Typhis tubifer, 
fig. 397. 

ULTIMUS. Montf. {The last.) A genus composed of Qvulum 
gibbosum, Auct. fig. 443, and other species in which the canals 
are not distinctly defined, nor elongated. This fanciful name is 
given to the genus on account of its being described in the last 
page of the book. 

UMBILICATED. (Umbilicatus.) Having an umbilicus, as Nau- 
tilus umbilicatus. 

UMBILICUS. (A navel.) The hollow formed in spiral shells 
when the inner side of the volutions do not join each other, so 
that the axis is hollow. The umbilicus is marked with the letter 
u in Helix algira, fig. 279. The term is also used- to express any 
small, neat, rounded hollow. 

UMBO. {The boss of a buckler or shield.) The point of a bivalve 
shell above the hinge, which constitutes the apex or nucleus of 
each valve, from which the longitudinal rays diverge, and the 
lines of growth, commencing at the minutest circle, descend in 
gradually enlarging concentric layers to the outer margin. The 
umbones will be marked with the letter u } in Cytherea, fig. 117. 

UMBRELLA. (A little shade.) Fam. Semiphyllidiana, Lam. 
Patelloidea, BL— Descr. Patelliform, sub-orbicular, compressed, 
rather irregular ; apex slightly raised, placed near the centre ; 
margin acute ; internal surface with a central, callous, coloured 
disc, surrounded by a continuous, irregular muscular impression. 
— Obs. This genus is known from Patella, by its continuous 
muscular impression. It is commonly called the Chinese Um- 
brella shell. There are but two species at present known ; the 
U. Mediterranea, and the U. Indica, fig. 233. 

UNDATED. {Unda, a wave.) Waved. 



UNIVALVE. 28") 

UNDULATED. (Undulatus.) Minutely waved. 

UNGUICULATED. {Unguis, a nail or hoof.) An unguiculated 
operculum is one in which the layers are disposed laterally, and 
the nucleus constitutes part of the outer edge. 

UNGULINA. Daud. (Ungula, a nail or claw.) Fam. Mactracea, 
Lam. Conchacea, Bl. — Bescr. Equivalve, sub-orbicular, sub-equi- 
lateral, with margins entire, simple, closed all round ; hinge with 
one short, sub-divided cardinal tooth in each valve, and a very 
minute additional tooth in one valve, an oblong ligamentary pit 
divided into two portions, one of which receives the cartilage, the 
external ligament is immediately below the umbones ; muscular 
impressions, two in each valve, oblong ; impression of the mantle 
entire. U. transversa, fig. 88. Coast of Africa. 

UNI-AURICULATED. Having one Auricle. See Auriculated. 

UNICORNUS. Montf. Monoceros, Auct. 

UNIO. (A pearl.) Fam. Nayades, Lam. Submytilacea, Bl. — 
Bescr. Inequilateral, equivalve, regular, free, pearly within, 
covered by a smooth epidermis without ; umbones prominent, 
generally corroded ; muscular impressions two in each valve, 
lateral, distant; the anterior composed of several small divisions ; 
hinge varying in age, species, and individuals.— Obs. The above 
description is framed so as to include all the genera of the La- 
marckian Nayades, together with Castalia, which are placed in 
the family Trigonacea, they are all fresh-water shells, commonly 
called fresh-water muscles. The distinctions of the various genera 
into which they have been divided, will be found in their respective 
places, and under the name Nayades. They are all represented 
in figures 140 to 152. Of these fig. 145 to 148, are more gene- 
rally considered as forming the genus Unio. 

UNIOPSIS. Sw. A sub-genus of Alasmodon. Sw. p. 382. 

UNIVALVE. (Unus, one ; valva, valve.) A shell consisting of a 
single piece, as distinguished from Bivalves and Multivalves, 
which are composed of two or more principal pieces. Spiral 
shells having an operculum, are called sub-bivalves by some 
authors. 



286 varix. 

UPPER- VALVE. The free valve in attached bivalves. 

UVIGERINA. D'Orb. A genus of microscopic Foraminifera. 

VAGINA. Megerle. Solen vagina, Auct. 

VAGINULA. (A little sheath, the husk of corn.) Class, Ptero- 
poda, Lam. — Descr. Pyramidal, slightly inflated in the centre, 
thin, fragile ; aperture oblong, with the edges turned slightly 
outwards. — Obs. The little shells of this genus, which are only 
known in a fossil state, differ from Cuvieria in being pointed at 
the extremity. Found in the tertiary beds of Bordeaux. V. Dau- 
dinii, fig. 225. 

VAGINULINA. D'Orb. A genus of microscopic Foraminifera. 

VALVATA. Mull. Fam. Peristomata, Lam. Cricostomata, Bl.— 
Descr. Thin, turbinated ; spire short, composed of from three to 
six rounded whorls ; aperture circular ; peritreme acute, entire ; 
operculum horny, spiral. — Obs. This genus of small shells resem- 
bles Cyclostoma, from which the recent species may be known 
by the horny texture of the external surface, being fresh-water 
shells. The fossils of course belong to the fresh-water formations. 
V. piscinalis, fig. 322. Europe and North America. 

VALVES. (Valva, a door, a folding piece.) The two pieces 
composing a bivalve shell, which close upon each other, turning 
upon a hinge consisting of a ligament, cartilage, and teeth. 
See Bivalve, Multivalve, and Univalve. 

VALVULINA. D'Orb. A genus of microscopic Foraminifera. 

VARIX. {A swelling vein.) A varix is formed on the outer surface 
of a spiral shell, by the thickened, reflected edge of a former 
aperture, after fresh deposits of testaceous matter have increased 
the size by adding to the growth of the shell beyond it. In this 
manner there are frequently many varices, or edges of former 
apertures, in various parts of the spire and the body whorl. They 
are sometimes placed at regular distances from each other, as in 
Harpa, fig. 419 ; sometimes continuous, as in Ranella, fig. 394 ; 
sometimes discontinuous, as in Triton, fig. 398 ; sometimes ramose, 
as in Murex, fig. 395 ; sometimes simple, as in Scalaria, fig. 351 ; 
sometimes spinose, as in Murex spinosus. The term varix has 



venus. 287 

also been applied to any swelling ridge, sack as that on the lower 
part of the columella of Ancillaria, fig. 456. 

VELATES. Montf. Neritina perversa, Auct. Fig. 326. 

VELLETIA. Gray? A genus described as differing from A ncylus 
in being dextral. Velletia lacustris, Ancylus lacustris, Auct. 
fig. Sowerby Gen. fig. 2. 

VELUTINA. Auct. Fam. Macrostomata, Lam.— Bescr. Sub- 
globose, covered with a velvety epidermis ; spire short, composed 
of two rapidly enlarged ventricose whorls ; aperture large, sub- 
ovate ; peritreme thin, entire, separated from the last whorl ; 
columella tortuous, thin. — Obs. This shell does not resemble any 
other genus in the family. Fig. 337. Northern Seas. 

VENERICARDIA. Lam. A genus composed of the shorter species 
of Cardita. 

VENERIRUPIS. Lam. (From Venus and rupis, a rock.) The 
oblong species of Venus Auct. which live in cavities of rocks and 
stones. This genus is united by Sowerby with some other species 
of Venus under the name Pullastra. V. Vulgaris, fig. 97. 

VENTRAL. (Venter, the belly.) The margin of a bivalve shell 
opposite the hinge. The under valve in Brachiopodous bivalves 
is the ventral valve. The ventral surface of an univalve spiral shell 
is that which faces the observer when the aperture is placed 
towards him. The ventral part of the whorls of symmetrical 
convolute shells, is the inner part, that which is nearest to the 
spire. 

VENTRAL SIPHON. In symmetrical convolute univalves, is one 
placed near the inner edge of the whorls. 

VENTRICOSE. {Ventricosus .) Swelled, rounded out, (homU Fr.) 
as Harpa ventricosa, fig. 419. 

VENUS. Auct. (Goddess of Beauty.) Fam. Marine Conchacea, 
Lam. Conchacea, Bl. — Bescr. Equivalve, inequilateral, sub-glo- 
bose, sub-ovate, transverse, externally rugose, striated, ribbed, 
cancellated or smooth ; margins entire, simple, close ; hinge 
with three more or less distinct cardinal teeth, diverging from the 
umbones in each valve; muscular impressions two, lateral, distant ; 
palleal impressions sinuated posteriorly ; ligament external. — Obs. 



288 VEXILLA. 

This extensive genus, including some bivalves of splendour and 
beauty, justifying the name given to it, may be known from 
Cytherea by the absence of a lateral tooth, which is found near 
the cardinal teeth in the latter. Artemis is distinguished not 
only by its beautiful form, but by the deep angular sinus in the 
palleal impression. Fig. 119, 119 a. Found mostly in tem- 
perate and tropical climates. 

VERMETUS. Adanson. Fam. Scalariana, Lam. Cricostomata, 
Bl. — Descr. Spiral at the apex, irregularly twisted towards the 
aperture; aperture round, small. — Obs. This shell resembles the 
Serpulse in general appearance, although it is regularly spiral near 
the apex. The animal is known to be a true mollusc, rather 
nearly allied to that of the genus Dentalium, which is also placed 
wrongly in the Lamarckian system. Vermetus Lumbricalis, 
fig. 345. Coast of Africa. 

VERMICULAR. {Vermicularis.) Worm-shaped, tubular, serpen- 
tine. Ex. Vermilia triquetra, fig. 7. 

VERMICULARIA. Lam. Vermetus, Adanson ; afterwards Ver- 
metus, Lam. 

VERMILIA. Lam. A genus composed of species of Serpula, which 
are attached by the whole length of the shell, no part being free. 
Vermilia triquetra, fig. 7. 

VERTEBRALINA. D'Orb. A genus of microscopic Foramini- 
fera. 

VERTEX. Apex. 

VERTIGO. Miill. Fam. Colimacea, Lam— Descr. Cylindrically 
fusiform, sinistral, hyaline ; aperture marginated, sinuated, denti- 
culated on the inner edge ; peristome sub-reflected. — Obs. This 
genus of minute land shells, resembles Pupa, but is a reversed, 
hyaline shell. Vertigo pusilla, fig 293. Europe. 

VERRUCA. Schum. Clitia, Leach. 

VESICA. Sw. A sub-genus of Bulinus, Sw. p. 360. 

VEXILLA. Sw. A genus of " Nassinae," Sw. thus described : 
^ General shape of Purpura, the inner lip flattened and depressed; 
the outer, when adult, thickened, inflected and toothed ; aperture 
wide ; picta Sw. Chem. pi. 157, f. 1504-5." Sw. Malac. p. 300. 



volutA. 28.9 

VIRGULINA. D'Orb. A genus of microscopic Foraminifera. 

VITRELLA. Sw. A sub-genus of " Buliinee," Sw. Lardn. Cy- 
clop. Malac. p. 360. 

VITRINA. Drap. (Fitreus, glassy.) Fam. Limacinea, Lam. and 
BL — Descr. Ovate, thin, glassy, fragile ; spire short ; last whorl 
large ; aperture wide, transverse ; peritreme simple ; columella 
spiral, linear. — Obs. This genus of land-shells is not known in a 
fossil state. The recent species are found among moss and grass, 
in shady situations. De Ferussac has divided this genus into 
Helicolimax, fig. 26.3, and Helixarion, fig. 262. 

VITULARIA. Sw. A genus of "Muricinae," Sw. thus described: 
" General habit of Muricidea, but the inner lip is depressed and 
flattened as in the Purpurince ; varices simple, nearly obsolete. 
Tuberculata, Sw. En, M. 419. fig. 1. (Mur ex vitulinus, Auct.)" 
Sw. p. 297. 

VIVIPARA. A generic name given by Montfort, and retained by 
some authors for Paludina, Lam. on account of the animals 
being viviparous, i. e. the young being perfectly formed before 
they leave the ovaries. 

VIVIPAROUS. See Vivipara. 

VOLUTA. Auct. {Volvo, to revolve.) Fam. Columellaria, Lam. 
Angyostomata, Bl. — Descr. Sub-ovate, rather angulated, thick, 
generally tuberculated, smooth ; spire short, conical, with a 
mammillated apex ; aperture generally angulated, large, terminat- 
ing anteriorly in a deep notch ; columella smooth, with several 
plaits, of which the lowest is the largest; outer lip thickened 
within.— Obs. The genus Voluta, as left by Linnaeus, is only cha- 
racterized by the folds on the columella, and includes many 
shells which, although they agree in this respect with the genus, 
are yet quite opposite to each other in all other characters. Thus 
the Auriculae, which are land shells, and have the aperture entire, 
are mixed up with others which are marine, and have a canal, as 
Turbinellee, and the Fasciolariae, and others which have merely 
a notch, as the true Volutes. This genus, as it is circumscribed 
at present, includes a great number of beautiful shells, most of 

u 



290 



WHORL. 



which are rich in colouring. Cymba and Melo have been se- 
parated by Mr. Broderip from the genus Voluta of Lamarck, 
for reasons stated in their respective descriptions. Fig. 443. 

VOLVARIA. Lam. (Volva, a shuttle.) Fam. Columellaria, Lam.— 
Bescr. Cylindrical, convolute, spirally striated ; spire very 
short, nearly hidden ; aperture narrow, as long as the whole shell ; 
columella with three oblique plaits; outer lip dentated. — Obs. 
The Volvaria are only known in a fossil state, and resemble some 
species of Bulla in general form, but are distinguished by the 
plaits on the columella. Fig. 439, V. concinna. 

VOLUTELLA. Sw. {A little volute.) A genus composed of those 
species of Ma rginella, Auct. which have the spire concealed, 
and the aperture smooth within. Fig. 438, Persicula of Schu- 
macher. 

VOLUTILITHES. Sw. {Voluta, and \idog, lithos, a stone.) A 
genus composed of some fossil species of Voluta, which have the 
plaits on the pillar generally numerous, indistinct, and some- 
times wanting altogether, with a pointed spire. Fig. 436, V. 
spinosa. 

VOLUTION. See Whorl. 

VORTICIALIS. Lam. A genus of microscopic Foraminifera. 

VULSELLA. Lam. (A little tongue.) Fam. Ostracea, Lau. 
Margaritacea, BL— Descr. Equivalve, irregular, longitudinal, 
compressed, oblong ; umbones separated by a slight area in both 
valves ; hinge with a large pit in the centre, containing the 
cartilage, the ligament being spread over the areas ; muscular 
impressions, one on each valve, sub-central, oblong. — Obs. This 
genus differs from Ostreea in the equality of the valves, and in 
having a hollow pit in the hinge for the cartilage. Vulsella lin- 
gulata, fig. 185. 

WATERING-POT. Aspergillum, fig. 44, commonly so called on 
account of the resemblance of its perforated termination to that 
of the spout of a watering-pot. 

WENTLE TRAP. Scalaria pretiosa, commonly so called. 

WHORL. A complete turn or revolution round the imaginary axis 



ZURAMA. ' 291 

of a spiral shell. The last whorl is called the body-whorl. The 
whorls are described as non-contiguous, when they do not touch 
each other ; continuous, in the opposite case. Depressed when 
they are flat. They are angulated, keeled, or coronated ; distinct, 
or indistinct. They are sometimes, as in Cyprsea, hidden by the 
last whorl. 

XYLOPHAGA. Sow. {fyXov, zylon, wood ; q>ayw, phago, to eat.) 
Fam. Tubiscolae, Lam. — Descr. Equivalve, globose, closed at the 
back ; with a large, angular hiatus in front ; hinge with a small 
curved tooth advancing from beneath the umbones in each valve. — 
Obs. This shell, which is found in a cylindrical cavity, eaten 
in wood by the animal, resembles Teredo, but has not the shelly 
tube, nor the posterior hiatus. X. dorsalis, fig. 50, 51. 

XYLOTRYA. Leach. Xylophaga, Sow. 

ZONITES. Montf. A genus formed of Helix Algira, and other 
similar species with depressed spires and large umbilici ; included 
in the sub-genus Helicella. Fig. 279. 

ZUA. Leach. A genus described as differing from Bulinus in having a 
polished epidermis, and a thickened, not reflected lip. Zua lu- 
brica, B. lubricus, Auct. 

ZURAMA. Leach. A sub-genus of Helix. H. pulchella, Auct. 
Gray's Turton, p. 41. 



u 2 



EXPLANATION OF PLATES, 



AND SYSTEMATIC VIEW OF THE 



LAMARCKIAN ARRANGEMENT. 



Class, ANNELIDES. 

Order, Sedentaria. 

Fam. Dorsalia. 

FIG. 

1. Siliquaria anguina, Agathirses, Montf. 

Fam. Maldania. 

2. Dentalium octogonum. 

3. Pharetrium fragile, with the outer tube broken. 

Fam. Serpulacea. 

4. Serpula bicarinata. 

5. Spirorbis Nautiloides, on sea-weed. 

6. Galeolaria decumbens, on a Conia. 

7. Vermilia triquetra. 

8. Spiroglyphus, on a portion of Patella. 

9. Magilus antiquus, old shell. Campulotus, Guild, (from Guerin.) 

10. The same, in a young state. 

1 1 . Leptoconchus striatus. 

12. Sty lifer astericola. 

13. The same, in a portion of Star-fish. 



EXPLANATION OF PLATES. 293 

Class, CIRRIPEDES. 
Order, Sessile Cirripedes* 

FIG. 

14. Tubicinella Balaenarum. 

15. Coronula Testudinaria. Chelonobia, Leach, Astrolepas, Klein. 

16. Balsenaris. Cetopirus, Ranz. 

17. — diadema. Diadema, Ranz. 

18. Chthalamus, Ranz. (from Blainville.) 

19. Platylepas pulchra, Leach. One valve separate, showing the 

inside. 

20. Clitia Verruca, Leach. Octhosia, Ranz. Verruca, Schum. 

21. Conia porosa. Teraclita, Schum. 

22. Elminius Leachii. 

23. Catophragmus imbricatus, (from Sowerby's Genera.) 

24. Octomeris angulosus, (from Sow. Gen.) 

25. Balanus tintinnabulum. 

26. Montagui. Acasta, Leach. 

27. galeatus, Conoplsea, Say. 

28. Creusia gregaria. b. showing the internal structure 

29. Nobia grandis. 

30. Savignium crenatum. ^ 

31. Pyrgoma cancellata. I 



32. Adna Anglicum. i 



Pyrgoma, Auct, 

33. Megatrema semicostata. 

Order, Pedunculated Cirripedes. 

34. Pentelasmis lsevis. Antifa, Lam. a. anterior, 

35. Scalpellum vulgare. 

36. Smilium Peronii. 

37. Pollicipespolymeus. Ramphidoma, Schum. 
37*.Pollicipes mitellus. Capitulum, Klein. 

38. Brismseus Rhophodius. 

39. Lithotrya dorsalis. Absia, Leach, Litholepas, Bl. 

40. Ibla Cuvieriana. 

41. Heptalasmis Warwickii. Octolasmis, Gray. 

42. Cineras vittatus. 

43. Otion Cuvieri. 



294 



EXPLANATION OF PLATES. 



Class, CONCHIFERA. 
Order, C. Dimyaria. 

Fam. Tubicolaria. 

FIG. 

44 » Aspergillum vaginiferum. Penicillus, Brug. 

45. Clavagella, a fossil species. 

46. Teredina personata. 

47- Lignite, pierced by Teredinse. 

48. Teredo navalis ; a, tube (from Sowerby' s Genera.) 

49. Wood bored by Teredo. 

50. Xylophaga dorsalis. Xylotrya, Leach. 

51. The same, in wood. 

(This would be more properly placed in Pholadaria.) 

52. Gastrochsena Modiolina, in the tube (from Sowerby's Genera.) 

53. Fistulana Clava. ~) , . 
e . m , „ ,, > (From Sowerby s Genera.) 

54. Tube of the same, y v J ' 

Fam. Pholadaria. 

55. Pholas Dactylus; a, plates of the hinge. 

56. papyracea. Pholadideea. 

57. Pholadomya Candida. 

58. Galeomma Turtoni. 

59. Front view of the same. 

(Here Xylophaga should be placed, see Tubicolaria.) 

Fam. Solenacea. 

60. Solen ensis. Ensis, Schum. Ensatella, Sw. 

61. Solen radiatus. Solenocurtus, Bl. Leguminaria, Schum. Siliqua, 

Megerle. 

62. Lepton squamosum, (from Turton.) 

63. Novaculina gangetica. 

64. Glanconome Chinensis. 

65. Panopsea Ausrtalis. 7 

~~ TT . n^ ^ • •• I (rrom Sowerby s Genera.) 

66. Hinge of Panopsea Faujasn. } 

67 Glycimeris Siliqua. 

68 Solenimya Mediterranea. 



EXPLANATION OF PLATES. 295 

FIG. 

Fam Myaria. 

69. Anatina rostrata. Auriscalpium, Megerle. 

70. Anatinella Sibbaldii. 

71. Mya truncata. 

72. Periploma insequivalvis. Osteodesma, Desh. a, bone of the 

hinge, (from Blainville.) 

73. Myochama anomioides ; lower valve with clavicle, and hinge of 

upper valve. 

74. External view of the same, attached to a Trigoiria. 

75. Cleidothserus Chamoides, attached valve. 

76. Upper valve of the same, with the clavicle. 

Fam. Mactracea. 

77. Lutraria papyracea. Ligula, Leach. Carinella, Adans. 

78. — Solenoides. Cutellus ? 

79. Mactra Stultorum. 

80. plicataria. Spisula 1 Gray. 

81. Spengleri. Schizodesma, Gray. 

82. bicolor. Mulinia, Gr y. 

83. Gnathodon cuneatus. Clathodon, Conrad 

84. Crassatella rostrata. 

85. Amphidesma reticulatum. 

86. Erycina plebeja. Mesodesma, Desh. 

87. Cuming mutica. 

88. Ungulina transversa, (from Sowerby's genera. 

Fam. Corbulacea. 

89. Corbula nucleus . 

90. Pandora rostrata 

Fam. Lithophagidse. 

91. Petricola Roccellaria. 

92. Carditoidea. Coralliophaga, Bl. 

93. Thracia corbuloides. 

94. Saxicava rugosa. 

95. Hiatella biaperta. 



296 EXPLANATION OF PLATES. 

FIG. 

96. Sphsenia Binghamii. 

97. Venerirupis vulgaris. 

Fam. Nymphacea. 

98. Sanguinolaria rosea. Lobaria, Schum. 
99. Diphos. Soletellina, BL ,~ 

100. Psammobia Ferroensis. Gari, Schum. 

101. Corbis fimbriata. Fimbria, Megerle. 

102. Grateloupia Moulinsii. (from Lea.) 

103. Egeria triangulata, (from Lea.) 

104. Lucina tigerina. 

105. Tellina radiata. 

106. lingua-felis ; a, showing the fold in the ventral margin. 

107. Tellinides rosea. 

108. Donax cuneatus. 

109. Capsa Braziliensis, young. 

110. Astarte Danmoniensis. Crassina, Lam. 

Fluviatiie Conchacea. 

111. Cyclas rivicola. Coruea, Megerle. 

112. Pisidium amnicum. Pisum, Megerle. 

1 13. Cyrena fuscata. Corbicula, Megerle. 

114. Cyrenoides Dupontia. 

115. Potamophila radiata. Galathsea, Lam. v. ventral margin. 

Marine Conchacea. 

116. Cyprina vulgaris. Arctica, Schum. 

117. Cythera Meretrix ; e. escutcheon. 
1 1 7 a. C Meroe ; Gen. Meroe. 

117 6 C. Tripla; Gen. Trigona. 
117 c C. maculata; Gen. Chione. 
117 d. C. Castrensis ; Gen. Circe. 

118. Artemis lincta ; s, sinus in the Palleal impression. 

.1 19. Venus cancellata. Antigona, Schum. a. anterior ; p. posterior ; 

c. cardinal teeth. 
119 a. V. Verrucosa. Dosina, Schum, 
120. Pullastra Textile. 



EXPLANATION OF PLATES. 29/ 

FIG. 

Fam. Cardiacea. 

121. Venericardia, recent species, resembling V. planicostata, Lam. 

122. Cardium Dionseum. Cardissa, Sw. Hemicardium, Nonnull. 

123. angulatum. 

123*. Greenlandicum. Aphrodita, Lea, Acardo, Sw. 

123**. hemicardium. Gen. Hemicardum. 

124. Cardita calyculata. 

125. Cypricardia angulata. 

126. Isocardia Moltkiana. 

127. Megalodon cucullatus, (from Sow. Min. Con.) 

128. Hippagus Isocardioides, (from Lea.) 

129. Hippopodium ponderosum, (from Sow. Min. Con.) 

130. Pachymya gigas, (from Sow. Min. Con.) 

Fam. Arcacea. 

131. Area antiquata. 

132. Bysso-arca Nose. 

133. Cucullsea auriculifera, (from Sowerby's Genera.) 

134. Pectunculus pilosus. 

1 35. Myopara costata, (from Lea.) 

136. Crenella. 

137. Nucula margaritacea, three views. 

138. Solenella Norrissii. 

Fam. Trigonacea. 

139. Trigonia pectinata. 

140. Castalia ambigua. Tetraplodon pectinatus, Spix. 

Fam. Nayades. 

141. Alasmodon complanatus, Say. Margaritana, Schum. 

142. Dipsas plicatus, Leach. Cristaria, Schum. 

143. Hyria corrugata, Lam. Paxyodon, Schum. Triplodon. 

144. Syrmatophora, Sow. Prisodon, Schum. Diplodon, Spix. 

145. Unio littoralis, Lam. Mysca ovata, Turton. 

147. Alatus. Symphynota, Lea. 

148. Atratus, Lam. Naia, Sw. 



298 EXPLANATION OF PLATES. 

FIG. 

149. Monocondylsea Paraguayana. 

150. Iridina elongata. Pleiodon, Conrad. > 

151. Mycetopus solenoides, D'Orb. Spatha, Lea. J 

152. Anodon Cataractus. 

Fam. Chamacea. 

153. Cham a Lazarus. Jataronus, Adanson. 

154. Diceras perversum, (from Sowerby's Genera.) 

155. Etheria semilunata. 

Order, MONOMYARIA. 

Fam. Tridacnacea. 

156. Hippopus maculatus. 

157. Tridacna elongata. 

Fam. Mytilacea. 

158. Mytilus achatinus. 

159. polymorphic. Dreissina. 

1G0. Modiola Tulipa. 

161. Lithodomus Dactylus. 

162. Pinna saccata. 

Fam. Malleacea. 

163. Avicula Hirundo. 

164. margaritifera. Meleagrina, Lam. 

165. Malleus Vulgaris. Himantopoda, Schum. 

166. Perna Ephippium. 

167. Catillus Lamarckii. Inoceramus, Sow. (from Blainville.) 

168. Crenatula mytoloides. ^ 

169. Gervillia aviculoides. > (from Sowerby's Genera.) 
1/0. Pulvinites Adansonii. J 

Fain. Pectinides. 

171. Pecten varius. Janera, Schum. 

172. Plica. Decadopecten, RuppelL 

173. Hinnites Pusio. Pecten Pusio, Lam. 

1 74 . Lima squamosa. 



EXPLANATION OF PLATES. 299 

FIG. 

175. Dianchora striata, (from Sow. Min. Con.) 

176. Plagiostoma spinosum, (from Sow. Min. Con.) 

177. Spondylus Americanus, hinge. (See Frontispiece.) 

178. Plicatula gibbosa. Harpax, Parkinson. 

179. Pedum Spondyloideum, (from Sow. Gen.) 

Fam. Ostracea. 

180. Ostrea edulis. 

181. Folium. Dendostrea, Sw. 

182. Grypheea incurva. 

183. Exogyra conica, (from Sow. Min. Con.) 

184. Placuna placenta. Gen. Placenta, Schum. 

185. Vulsella lingulata. 

186. Anomia Ephippium. 

187. Hinge of the same, with bony process. 

188. Hinge, showing the fissure. 

189. Placunanomia Cumingii. 

190. Hinge of the same, showing the fissure. 

191. Hinge of the unattached valve. 

192. Mulleria. (from Sow. Gen.) 

Fam. Rudistis. 

193. Sphserulites foliacea. (Radiolites is more conical.) 

194. Calceola Sandalina. 

196. Birostrites insequiloba, internal cast of Sphaerulites. 

197. a. Crania personata, dorsal valve ; b. C. antiquata, interior. 

(This would be more properly placed in Brachiopoda.) 

198. Hippurites Cornucopia, (from Blainville.) 

199. Hipponyx Cornucopia, attached valve. 

200. Upper valve of the same. 

Fam. Brachipoda. 

201. Orbicula lsevis. 

202. Terebratula Psittacea; a. anterior margin, 

203. Atrypa reticularis. Trigonotreta, Konig. 

204. Cyrtia exporrecta, 



300 EXPLANATION OF PLATES. 

FIG. 

205. Delthyris plycotes, (from Dalman.) 

206. Leptsena depressa, Dalman. Producta, Sow. (from Sow. Gen.) 
206*. Producta antiquata. 

207. Orthis basalis, Dalman. Strophomena, Rafinesque. 

208. TrigoDOsemus Lyra, Konig. 

209. Magas pumilus, Sow. 

210. Gypidia conchidium, (from Dalman.) 

211. Interior of the large valve of the same, (from Dalman.) 

212. Pentamems Aylesfordii, (from Sow. Min. Con.) 
213. lsevis. 

^ > Trigonotreta, Konig, (from Sow. Gen.) 

215. dorsatus. j & & v 

216. Thecidium recurvirostrum. 

(Here should come Crania, see Rudistes.) 

217. Pycnodonta radiata, (from Fischer.) 

218. Hinge of the same. 

219. Lingula Anatina. 

Class, MOLLUSCA. 

Order, Pteropoda. 

220. Atlanta helicialis. 

221. Cleodora cuspidata. 

222. Creseis spinifera. 

223. Cuvieria columella. 

224. Spiratella limacinea, with animal ; Limacella, Lam. Limacina 

Cuvier. (from Blainville.) 

225. Vaginula Daudinii. 

226. Hyalsea tridentata. Archonte,. Montf. 

Order, Gasteropoda. 

Fam. Phyllidiana. 

227. Chiton spinosus. 

228. Chitonellus striatus. (from Sow. Gen ) 

229. Patella oculus ; a. anterior. 



EXPLANATION OF PLATES. 301 

FIG. 

230. Patella pellucida. Helcion,f Montf. Ansates, Klein. 

231. Patelloida Antillarum. Lottia, Gray. 
231*. Siphonaria Sipho. 

Fam. Semiphyllidiana. 

232. Pleurobranchus merabranaceus. 

233. Umbrella indica. Gastroplax, Bl. 

Fam. Calyptracea. 

234. Calyptraee Equestris. 

23.5. extinctorium. 

236. auriculata. 

237. Pileus. Infundibulum, Montf. 

238. Side view of the same. 

239. Crepidula Porcellana. 

240. Capulus ungaricus, two views. Pileopsis, Lam. 

241. Emarginula fissura. 

242. Parmophorus elongatus. Scutus, Montf. 

243. Rimula Blainvillii. 

244. Cemoria Flemingii. 

245. Fissurella oriens. 

246. Ancylus flu viatilis. 

Fam. Bullaeana. 

247. Bulla fragilis. Akera, Nonnul. 

248. aperta. Bullsea, Lam. 

249. aplustre. Aplustre, Schum. 

250. Naucum. Atys, Montf. 

251. lignaria. Scaphander, Montf. 

252. — — Ampulla. 

253. lineata. 

Fam. Aplysiacea. 

254. Aplysia Petersoni. 

255. Dolabella Rumphii. 

Fam. Limacinea. 

256. Parmacella calyculata, Cryptella. Webb. 



302 EXPLANATION OF PLATES. 

FIG. 

257. Parmacella Olivieri. (from De Ferussac.) 
258. pallidum, (from De Ferussac.) 

259. Limax antiquorum. 

260. Plectophorus corninus, (from De Ferussac.) 

26 1 . Testacella Haliotoidea. 

262. Helixarion, Cuv. } . 

nco „ ,. ,. ni .-, } Vitrma, Drap. Cobresia, Haubner. 

263. Helicohmax pellucida. ) 

Order, Trachelipoda. 
Fam. Colimacea. 

Sub-genera of De Fer 

264. Helix brevipes, Drap Helicoplianta. 

265. Succinea amphibia. i 

266. patula. Amphibulima, Lam. \ Cochlohydra. 

267. Helix hgemastoma. Acarus, -v 

Montf. # 

268. Pomatia, y Helicogena. 

269. Streptaxis contusa, Gray. V 

270. Another view of the same. -' 

271. Anastoma depressum. 

272. Another view of the same. 

273. Helix nux-denticulata. 

> nelicodonta. 

274. Proserpina nitida. 

275. Polygyra septemvolva., 

276. Another view of the same. 

277. Carocolla Lamarckii. i 

278. Helix pil eus. Geotrochus, Sw. 3 * 

279. algira. Zonites, Montf. > 

280. citrina. Naninia, Gray. S 

281. epistilum Helicostyla. 

282. Bulinus rosaceus ; a. apex. 
283. Guadaloupensis ; Bulinulus, 

Leach. V Cochlostyla. 

284. Lyonetianus. Gibbus, Montf. 

285. lubricus. Cionella, Jeffreys. 



Cochlodonta. 



EXPLANATION OF PLATES. 303 

Sub-genera De Fer. 

FIG. 

286. Achatina virginea Liguus, Montf. } 

287. Achatinella, Sw. \ ' ' Cochlitoma - 

288. Polyphemus Glans, Montf Cochlicopa. 

289. Bulinus decollatus, in a young state . . Cochlicella. 

290. Azeea tridens, Jeffreys. Turbo tridens, J 

Gmelinlj Cochlo S ena ' 

291. PupaUva. 

292. Alsea marginata ; Jeffreys. 

293. Vertigo pusilla. 

294. Megaspira Ruschenbergiana. 

295. Clausilia Macascarensis ; a, a break, \ 

to show the clausium. > . Cochlodina 

296. Balea fragilis, / 

297. Auricula Judse. 

298. coniformis. Conovulum, Lara. Melampus, Montf. 

299. Pedipes Adansonii. 
299*.Scarabaeus imbriura. 

300. Chilina Dombeyana. 

301. Carychium minimum. 

302. Partula Australis. 

303. Cyclostoma ferrugineum. 

304. — In volvulus. Cyclophorus, Montf. 

305. Nematura Deltse. 

306. Helicina major. 

307. Operculum of the same. 

Fam. Lymneana. 

308. Limnsea stagnalis. 

309. auricularia. Radix, Montf. 

310. castanea. Physa, Drap. 

311. Planorbis corneus. 

312. Planaria niteus, (from Lea.) 

Fam. Melaniana. 

313. Melania subulata. Melas, Montf. 



304 EXPLANATION OF PLATES. 

FIG. 

314. Melania prserosa and monodontoides. Anculosa, Say. 

315. Melanopsis costata. Faunus, Montf. 

316. Pirena terebralis. 

317. Pasithsea striata, (from Lea.) 

Fam. Peristomata. 

318. Ampullaria fasciata. Amphibola ; «, aperture. 
319. Guinaica. Lanistes, Montf. 

320. Cornu-arietis. Ceradotes, Guild. 

321. Paludina Bengalensis. 

322. Valvata piscinalis. 

Fam, Neritacea. 

323. Navicella elliptica. 

324. Neritina virginea. Theodoxus, Montf. 

325. ■. spinosa. Clithon, Montf. 

326. perversa. Velates, Montf. (from Sow. Gen.) 

327. Natica mamilla. Polinices, Montf. 
328. lineata. 

330. Nerita peloronta. Peloronta, Oken. 

331. Neritopsis granosa. 

332. Pileolus plicatus. 

333. Janthina fragilis. 

Fam. Macrostomata. 

334. Sigaretus concavus. 

335. Stomatia Phymotis. 

336. Stomatella imbricata. 

337. Velutina laevigata. Galericulus, Nonnul. 

338. Haliotis rubra, young. 

339. tricostalis, Lam. Padollus, Montf. 

340. Scissurellaelatior, magnified. 

341. Pleurotomaria reticulata. 



( (from Sow. Gen.) 



Fam. Plicacea. 

342. Pyramidella terebellum. 

343. Tornatella solidula Acteon, Montf. 



EXPLANATION OF PLATES. 305 

FIG. 

344. Monoptygma elegans. (from Lea.) 

Fam, Scalariana. 

345. Vermetus lumbricalis. 

346. Rissoa reticulata. 

347. Eulima labiosa. 

348. marmorata. Bonellia, Desh. 

349. Cirrus nodosus, Sow. 

350. Euomphalus pentangulus. (from Sow. Min. Con.) 

351. Scalaria Pallassii. Aciona, Leach. 

352. Delphinula laciniata. 

Fam. Turbinacea. 

353. Solarium perspectivum. 

354. Bifrons. Bifrontia and Omalaxis, Desh. 

355. Orbis Rotella. (from Lea.) 

356. Another view of the same. 

357. Kotella vestiaria, Pitonellus, Montf. 

358. Trochus stellaris, Lam. Calcar, Montf. Turbo, Sow. 

359. — maculatus. Tectus, Montf. 

360. — agglutinans. Phorus. 

361. Pharaonis. Clauculus, Montf. 

362. Margarita tseniata. 

363 . Littorina vulgaris . 
363*.Assiminea Grayana. 

364. Lacuna pallidula. 

365. Planaxis sulcata. 

366. Monodonta labeo ; Odontis, Sow. 

367. Phasianella variegata. 

368. Turbo setosus. Marmarostoma, Sw. 

369. Tuba striata, (from Lea.) 

370. Turritella imbricata. 

371. Monotygma, Gray. 

Fam. Canalifera. 
372 Cerithium Aluco, front. 



306 EXPLANATION OF PLATES. 

FIG. 

374. Nerinea Goodhallii. (from Geol. Trans.) - 

375. Triphora plicata, (from Deshayes.) 

376. End view of the same. 

377. Potamis muricata. Pyrazus, Montf. Tympanostomata, Schum. 

378. Ceritliium Telescopium. Gen. Telescopium. 

379. Pleurotoma Babylonia; a, a, extremities of the axis. 
381. strombiformis, Clavatula, Lam. 

382. Turbinella corniger. Scolymis, Sw. 

383. polygona. Polygonum, Schum. 

384. Spirillus. Gen. Pyrella, Sw. Turbinella spirillus, Auct. 

385. Cancellaria reticulata. 

386. Fasciolaria Trapezium. 

387. Fusus Colus; a, anterior of the aperture ; p, posterior. 

388. Pyrula perversa. Fulgur, Montf. 

389- papyracea. Rapanus, Schum. Bulbus, Humph. Ra- 

pella, Sw. 

390. Ficus. Ficula, Sw. 

391. Struthiolaria straminea. 

393. Ranella ranina. Apollon, Montf. 

394. neglecta. Bufo, Montf. 

395. Murex inflatus. Chicoreus, Montf. 

396. haustellum. Brontes, Montf. 

397. Typhis tubifer. (from Deshayes.) 

398. Triton pilearis. 

399. cutaceus. Aquillus, Montf. 

400. Lotorium. Lotorium, Montf. 

401. anus. Persona, Montf. 

Fam. Alatse. 

402. Rostellaria curvirostrum. 

403. columbaria. Hippochrenes, Montf. 

(from Sow. Gen.) 

404. Pes-pelicani. Aporrhais, Petiver. 

405. Pteroceras aurantiacum. 

406. Strombus pugilis. 



EXPLANATION OF PLATES. 307 

FIG. 

Fam. Purpurifera. 

407. Cassidaria echinophora. Morio, Montf. 

408. Side view of the outer lip, to shew the canal. 

409. Oniscia Oniscus. Cassidara. 

410. Cassis tuberosa, reduced. 

411. erinaceus. Cassidea, Sw. 

412. testiculus. Cyprsecassis, Stutchbury, 

413. Ricinula horrida. Sistrum, Montf. 

414. Purpura persica. 

415. Tritonidea (Pollia, Gray.) articularis. 

416. Phos senticosa. 

417. Monoceros crassilabrum. 

418. Concholepas Peruviana. 

419. Harpa ventricosa. 

420. Dolium maculatum. 

421. Buccinum undatum ; a, anterior of the aperture ; p, posterior. 

422. papillosum. Alectrion, Montf. 

423. Nassa arcularia. 

424. neritoidea. Cyclops, Montf. 

425. Cyllene, Gray. 

426. Eburna Zeylanica. 

427. Bullia vittata. 

428. Terebra maculata. Subula, Bl. 

429. Trichotropis bicarinata. 

Fam. Columellata. 

430. Columbella mercatoria. 

431. Mitra plicaria ; c, termination of the columella. 

432. Conohelix marmorata. 

433. Voluta Vespertilio. Cymbiola, Sw. 

434. Cymba porcina. 

435. Melo ^athiopicus. 

436. Volutilithes spinosus. 

437. Marginella Glabella. Glabella, Sw. Cucumis, Klein. 

438. persicula. Volutella, Sw. Persicula, Schum. 

x 2 



308 EXPLANATION OF PLATES. 

FIG. 

439. Volvaria concinna. 

Fam, Convolute. 

440. Ovulum Ovum. 

44 1 . verrucosum. Calpuraus, Montf. 

442. Volva. Radius, Montf. 

443. gibbosum. Uitimus, Montf> 

444. Cyprseovulum capense. 

445. Cyprsea arabica, back. 

446. The same, front. 

447. Cyprsea Algoensis. Luponia, Gray, front, 

449. Pediculus. Trivia, Gray, back. 

450. The same, front. 

451. Terebellum convolutum. Seraphs, Montf. 

452. subulatum, front. 

454. Erato Mangeriae. 

455. Ancillaria glabrata. AnoJax, Brongn, 

456. |r* cinnamonea. 

457. Oliva Maura. 

458. subulata. Hiatula, Sw. 

459. Conus nocturnus. Rhombus, Montf, 

460. Nussatella. Hermes, Montf. 

461. Textile. Cylinder, Montf. 

462. geographus. Rollus, Montf. 

Order. Cephalopoda. 
First Division. Polythalamous Cephalopoda. 

Fam. Orthocerata. 

463. Amplexus coralloides. (from Sow. Min. Con.) 

464. Orthoceratites annulatus. 

465. Nodosaria aequalis. 

466. Belemnites, with the outer coat broken to shew the alveole. 
467. portion of the alveole separated. 

468. hastatus. Hibolithes, Montf. (from Blainville.) 

469. Conularia quadrisulcata. 



EXPLANATION OF PLATES. 309 

FIG. 

470. Conilites pyramidatus, (from Blainville.) 

Fam. Lituacea. 

471. Spirula Peronii . 

Fam. Nautilacea. 

472. Nummulites buticularis, outside. Helicites, Bl. Camerina, 

Brookes. 

473. The same inside, to shew the chambers. 

474. Nautilus pompilius, young. See Frontispiece. 

475. Simplegas sulcata. 

476. Endosiphonites. (from Camb. Philos. Trans.) 

Fam. Ammonacea. 
477- Ammonoceras. (from Blainville.) 

478. Ammonites ; a, break in the shell, showing the sinuous septa. 

479. Orbulites crassus. Globulites, Nonnul. Angulites, Montf. 

reduced. 
479*. discus. Aganides, Montf. 

480. Goniatites striatus. 

481. Scaphites sequalis. 

482. Crioceratites Duvallii. 

483. Turrilites tuberculatus. 

484. Baculites Faujasii. Portion near the centre. 

484*. Hamites cylindricus ; a, internal cast of part of the shell ; 
b y hollow external cast of the remainder. 

Second Division. Monothalamous Cephalopoda. 

485. Argonauta Argo. 

486. Bellerophon tenuifasciata. (from Sow. Gen.) 

487. The same, shewing the dorsal keel. 

Order. Heteropoda. 

488. Carinaria Mediterranea. 



310 



EXPLANATION OF THE NEW PLATES. 



Order, Sessile Cirripede-s. 

489. Pyrgoma monticularia. Sab genus, Daracia, Gray, back 

and front. 

490. The same, in situ. 

Fam. Myaria. 

491. Lyonsia Norvegica. Anatina, Nonnul. Inside view of both 

valves. 

492. Outside, with the valves closed. 

493. Nsera longirostrum. Anatina longirostris, Lam. Inside of 

both valves. 

494. Outside, with both valves closed. 

495. A smaller species of Naera, shewing the inequality of the 

valves. 

Fam. Mactracea. 

496. Amphidesma tennis. Abra, Leach. 

497. Ervillia nitens. 

Fam. Corbulaeea. 

498. Potamomya, of some authors. A fresh-water shell resembling 

Corbula. Outside, valves closed. 

499. Inside of both valves. 

Fluviatile Conchacea. 

500. Cyclas amnica. Pera, Leach. 

Fam. Cardiacea. 

501. Cardilia semisulcata. Isocardia semisulcata, Lam. Internal 

view. 

502. External view of the same valve. 

503. Cardium apertum. Papyridea, Sw. 



EXPLANATION OF NEW PLATES. 311 

FIG. 

504. The same, shewing the umbones. 

505. Pleurorynchus, fossil, (from Mineral Conchology.) 

Fam. Phyllidiana. 

506. Chiton fascicularis. Phakellopleura, Guild. 

507. — — amiculatus. Amicula, Gray. 

Fam. Calyptracea. 

508. Scutella, Brod. Internal view. 

509. External view of the same. 

510. Ancylus, a reversed species, illustrating the genus Velletia, 

Gray. Enlarged view. 

511. The same, natural size. 

512. Pedicularia. Enlarged figure, (copied from Swainson.) 

513. The same, natural size, growing on coral. 

Fam. Colimacea. 

514. Achatina? octona. Macrospira, Guild. 

515. Stenopus cruentatus, Guild. Under side. 

516. lividus. 

517. Helix, the aperture covered by the epiphragm. 

518. Pupa secale, Drap. Abida, Leach. 

519. pagoda. Gonidomus, Sw. 

520. Truncatella, enlarged figure. 

52 1 . The same, natural size. 

522. Auricula caprella. Gen. Caprella, Nonnul. Front view. 

523. The same, dorsal view. 

524. Pupinavitrea 

526. antiquata. 

527. Namezii. 

528. lubrica. Callia? Gray. 

529. Cyclostoma, a pupiform species. Megalomastoma, Guild. 

530. Planorbulum. Cyclotus, Guild. 

531. a similar species, with the complicated notch at 

the posterior part of the aperture. Pterocyclos, Gray. 

532. Helicina acutissima, nobis. View of the under side. Trocha- 

tella, Sw. 




312 EXPLANATION OF NEW PLATES. 

The same in profile. 

Strophostoma, Desh. three views. 

Fam* Peristomata. 
Paludina impura. Bithinia, Gray ? 
Ampullaria avellana. Thallicera, Sw. Ampullarina ? 

539. A species of Ampullaria having a thickened ledge on which 

the shelly operculum rests. Pachystoma, Guild, changed to 
Pachylabra, Sw. 

Fam. Plicacea. 

540. Ringicula, Desh. A fossil species, front view. 

541. Back view of the same. 

Fam. Turbinacea. 

542. Turbo nicobaricus. Chrysostoma, Sw. 

543. Trochus Iris. Elenchus, Humph. 

Fam, Purpurifera. 

544. Purpura vexilla. Gen. Vexilla, Sw. 

545. Priamus. Achatina priamus, Auct. The propriety of placing 

it in this family will depend upon the correctness of the state- 
ment made by Dr. Beck that this shell is marine, and pos- 
sesses an operculum. 

546. Purpura crispata. Polytropa, Sw. 

547. Pseudoliva plumbea. Gastridium, Sow. 

Fam. Canalifera. 

548. Fusus longevus. Clavalithes, Sw. 

549. bulbiformis. Leiostoma, Sw. 

550. Pyrella, Sw. Turbinella Spirillus, Auct. 

551. Pleurotoma lineata. Tomella, Sw. 

552. Pyrula melongena Gen. Myristica, Sw. 

553. Murex vitulinus, Gen. Vitulina, Sw. v 

554. Typhis Sowerbii. 

555. A brown variety of the same. 

556. Typhis Cumingii. 



EXPLANATION OF NEW PLATES. 313 

FIG. 

Fam. Columellata. 

557. Voluta Vexillum. Harpula, Sw. 

558. Mitra monodonta. Mitreola, Sw. 

559. bicolor. Mitrella, Sw. 

560. Columbella nitidella. Gen. Nitidella, Sw. 

Fam. Convolutae. 

561. Oliva volutella. Gen. Lamprodoma, Sw. 

562. maura. 

563. Cyprsea Globulus. Gen. Globularia, Sw. 
564. pulchella, fossil. Gen. Cyprsedia, Sw. 



THE END. 



O. NORMAN, PRINTER, MAIDEN LANE, COVENT GARDEN. 



TABLE OF LAMARCK'S CONCJ 



Classes of Inver- Orders, 

tebrated Animals. 

ANNELIDES . Sedentary 



I 



CIRRIPEDES .f Sessile ' * ' ' 

i Pedunculated 



Multivalve. 



DlMYARIA 



CONCHIFERA 

Bivalve. 



^MONOMYARIA . 



Pteropoda 



Gasteropoda 



Trachellipoda 



MOLLUSCA . . 

Univalve. 



Families. 

r Dorsalia Siliquaria. 

1 Maldania Dentalium. 

Serpulacea Serpula, Spir 

t t S Tubicinella, < 
" " C Pyrgoma Cre 

Anatifer, Pol 

rTubicolaria \ Aspergiljum, 

( Teredo, Tere 

Pholadaria Pholas, Gast 

Solenacea Solen, Panop 

Myaria Mya, Anatin 

Mactracea Lutraria, Me 

Corbulacea Corbula, Pan 

Lithophagidce Saxicava, Pe 

Nymphacea \ Sanguinolaris 

* \ I Tellinides, C- 

Fluviatile Conchacea . Cyclas Cyre 
Marine Conchacea . . Cyprina, Cy 

Cardiacea Cardium, Cai 

Arcacea Cucullsea, A 

Trigonacea Trigonia, Ca 

Nayades Tj n i , Hyria, 

-Chamacea Diceras, Cha 

-Tridacnacea Tridacna, Hi 

Mytilacea Modiola, My 

Malleucea Crenatula, P 

Fectenides Pedum, Lin 

Ostracea Gryphaea, Os 

Rudistes Sphrerulites, 

^-Brachiopoda Orbicula, Te 

Hyalaea, Cle 

Fhyllidiana Chiton Chit 

Semrphyllidiana . . . Pleurobrancl 
e Parmopnoru! 

< Calyptracea £ Pileopsis, Cr 

. \Bulleana Bulla, Bull* 

| Aplysiacea Aplysia Dol 

^Limacinea Parmacella, J 

c Helix, Caroc 
Colimacea I Bulinus, Acl 

Lymneana S*? ^? 1 

Melaniana Melania, Me 

Peristomata Valvata, Pal 

Neritacea Navicella, N 



Macrostomata 



Stomatia, St< 



polythalamous 
Cephalopoda . 



monothalamous 

Cephalopoda . . 

l Heteropoda . . . 



Plicacea ...WW Tornatella, I 

<[ Scalariana Vermetus, S 

c Solarium, K 
Turbinacea < Turitell 

Canalifera < Cerithium, 1 

J j Fusus, Pyru 

Alata <■ Rostellaria, 

Purpurifera $ Cassidaria, ( 

^ J I Harpa, Doli 

Columellata Columbella, 

^Convoluta Ovulum, Cy 

r Orthocerata Belemnites, 

Lituacea Spirula, Spir 

| Cristacea Renulina, Ci 

J Spherulacea Miliola, Gyi 

s Radiolacea Rotalites, Le 

Nautilacea S Discorbites, 

i Nummilites, 
L-Ammonacea Ammonites, 



Argonauta. 
Carinaria. 



TABLE OF LAMARCK'S CONCHOLOGICAL SYSTEM. 



ANNKMUES . 



■ /j 1)( -,,i/i-i 



Siliqnaria. 



^ Pedunccla- 



, \I.V;llu- 



■/'(,'.;, ■■•'■n-M . 



Wyarw 

Corbulacea 

Lithopbagida: 

Fluviatile Conchacea 



Trigonact 



I', ,h „«!<■< 
Ostracea . 



Scapula, Spnorbis, Galeolnria, \' 

* Tubicinella, Coronula, Balanus, 
I I'vru'nnia Creusifl. 

■\ii:itiP'r, I'nllii-ij.es, Cmexas, Otion. 
V \^,.-!-.-i!hn:i. ( 'lava^lla, J'Vtiilarin. Septaria. 

* T,r,,lo, Trralina. 
Pliolas. Gastrochsenn. 
Solen, Panopa-a, Glycimeris. 
Mva, Anatina. 

Lutraria, Mactra, Cra^atcdla, Krycma, I n-uliua, Solemya, Ampliuksmn 
Corbula, Pandora. 
Saxieava, Petricola, Venerirupis. 

\ Samruimdaria, P>auiiu.-.bia , 1 '.-arnmota'a, Tellina. 
I 'l.'liinidi'f. Corbis, I.ucma, IKmax, t'apsa, Crassina. 

■ Cvclas, Cvrona, Galathsca. 

■ Cyprina, Vyihmva, V.aio-. \ . ■u-nranlia. 
• ('ardium, <':irdita. < 'vpnranlia, lli.n.lla, Isocardia. 

■ Cucullcea, Area, Pectunculus, Nucula. 

■ Triform, Castalia. 

■ I'nio, Ilyria, Anodon, Iridina. 

■ Dicpras, Omnia, Etheria. 

■ Tndacna, Hippopue. 
. Mrjiliola. Mytilus, Pinna. 

■ (Vnauila, lV>ma, Malleus, Avicida. M.dca;;nna. 
. Pedum, Lima, Plains torn a, Pecten, Plicatola, Spondylus, Portopsis. 

■ Crvphaa, U>tnca, YuKdla, I'lacuna, Anomia. 

■ Sph.vrnlit^. lladmlit.^, (.'al.'.-l.i, JSirostrir. s, Disrina, Crania. 

* Orbicula,Terebratula, Lunula. 
Hyalaa, ('Irndora. lamacma, Cymbulia. 

rPhvllidiana Cbiton, Cbitonellus, Patella. 

[s,m,„h»ll„lLL' ' ' ' Pleurobranchus, Umbrella. 
Semiphytlidmna . . . p ^ ^^ i,,,,-,,.,,,,,,!,, vplmnnn.i, Fissurella. 

J Calyptmcea J Pileopsi-. ( .dvptiM.a, ( 'ivpidula, Ancylus. 

i n„n„,~» Bulla, Bullsa. 

Sri' Aplysia, Dolabella. 

■_1 ,,;,,.,',, ■ •■ ■ }v inn:il ,.)l;,. i, ,,)!:!.•:., ']. -ta. -.'11a. Vitnna. 

, Helix, Car 11a. Ana^nma. IMicinn, Pupa, Clausilia. 

1 Bulinus, Arliatina, Succinea, Auricula, Cyclostoma. 
I'lanorbis, l'liysa, Lymna>a. 
Mclama, Mclanopsis, Pirena. 
Valvala, Paludina, Ampullaria. 
Navir.-lla, Vntina. Xmia, N adca, Janthina. 
Stomatia, Stomatella, llaliotis. 

Vermetus, Scalaria, Delphinula. 
t Solarium, Rotella, Trochus, Monodonta, Turbo, Planaxis, Pliaeianella, 
j Turitella. 

\ Oritlmim, Pleuiv.tomn, Tmbmclla. Caiicrllaiaa, I'aSCJolaria. 

1 Fusus, Pvnila, Ttanella, Murex, Triton. 

■ Iloit-Hai-'ia, Strombus, Pteroceras. 

S Ca?sidana, Ca?M.-, IJi.anula. l'ur|aira , Wcmoc.-i'^, < oncholepas. 

) llarj.a, hi.li.ini. r.inainuui, l.lairna. Terebra. 

Colnmbrlla, Miu.i, \ -luta, Maiviiudla, Volvaria. 

Ovulum, Cypra-a, l.Hiva, Aiinllana, Genus. 

ISelemnitPs* Ortbocoras, Xodosaria, Uijipurites, Conilitea. 

Spirula, Spirolina, Lituola. 

Rr-nuljna, (.'risu-llaria, Orbiculina. 

Jliliola, Gyrogona, Melon ia, ( Microscopic.) 

Rotaht.-., I^.TLl i.-n S L] i:l . Pla.-.'llMll.l. I Ml. n.s, I 

[ii-f.-uvbii-'s, ^i.b.'i.'lit.-s Pnlv.-iuin.dla, Vorticialis. 
. Nummilites, Nautilus. 

Argonauta. 




VILLE. 



nia, Saracen aria, Textularia. 

, Helicites, Placentula, Vorticialis, Siderolite- 

yonilites, Orthoceras, Baculites. 

Spirula, Spirolina, Hamites, Ammonoceraa. 

huris. 

imonites, Simplegas. 

Lenticulina. 



Fusus, Pyrula, Fasciolaria. 

Triton, Strutlaiolaria, Ranella, Murex. 

tnopsis, Planaxis, Subula, Terebra. 

pa, Dolium, Cassis, Cassidaria, Ricinula. 

>ncholepas, Terebra, Mitra. 

um, Oliva, Ancillaria. 
la, Volvaria, Cypraea, Ovulum. 

rotomaria, Littorina, Debpbinula, Cyclostoma. 
ria, Proto, Turitella, Vermetus. 

Velates, Pileolus, Navicella, Natica. 
elania, Rissoa, Phasianella, Pleurocerus. 



itella, To-mo-gerus, Pyramidella. 

tina, Clausilia. 

r itrina, Testacella, Parmacella, Limacella, Limax. 



MALACOZ( 



SUB-T^ 

MA lento: 



netus. 
TYPi>ulia. 



nauta. 



Parmopborus. 

apulus, Hipponyx, Notrema. 

:opbomena, Diancbora. 
Podopsis, Orbicula, Crania, 
Radiolites, Birostrites, Calceola. 
i, Gryphae. 

nnites, Pecten, Pedum, Lima. 

la, Perna, Crenatula. 

.lvinites, Gervillia. 

ila. 

Tridacna, Hippopus, Isocardium, Trigonia 
Lucina, Cyclas. 
a, Crassatella. 
alliopbaga. 
a, Ungulina. 
ia, M} r a, Lutricola. 
Sanguinolaria, Solenocurtus. 
,, Glycimeris, Saxicava, Byssomya. 
ia, Clavagella, Aspergillum. 
Fristulana, Septaria. 
Polylepas, Litbolepas. 
ia, Conia, Creusia, Pyrgoma, Clitbalamis. 
topirus, Diadema, Tubicinella. 



TABLE OF THE CONCHOLOGICAL SYSTEM OF DE BLAINVILLE. 



l^'inilina. Peneroplis. 

Ml!i.il;i, IVIhmti's, :\h'l..ni;i, 




Orbirulina. lb-licit-'-. Plac-ntiila, \". irl.iri.ili~ . ;<,:[,- 
Belemnites, Conubria, C.yiiln,-,. ( (rtln.reras, Uaculites. 
Ictbyaarcolites, Lituola, S^imla, Spirulnia, Ilnmitea, Ammonocer 
Crepidulina, Oreas, Lintburis. 
Discorbis, Scapbites, Ammonitf-s, Simplegaa. 
I'.ilvsli'iu.'ll.', Nautilus, Lenticulina. 

I'lcurotoma, Rosli'll.irin. Fiisus. I'vmln, Fasciolaria. 
Turbinella, Columbelb, Triton, Stmtbiuhria. Ranella, Murex. 

Pyrena, JUeluni.p.-i-. 1 ' 1 .■ u j ; . x i ■- . Subula, Terebra. 
F.bunia, I ;i|.L-inum. ilarpa. I Ir.imm. Cassj,, Ca-.i.lana, Iiiniiu'' 

Cnncclbrki, Purpura, I ' ■li.ib.pa-., T-.-ivbra, Mitra. 

StrnmbiK, L'.'iHK. 'IVrolj-lliini, u]u-:i, Ancillana. 
Voluta, iHitra, Muiynic-lla, Volvana. Cvprava, Ovulum. 
Solarium, Troclms. 

Moil..'] .1. 'I'lirli.t, Plrllp.fi.rnarin, l,iil..)'lii:i. ! )■ l[,!i I [] i| la . Cvcln, 

Paludinn. V.ilrnta, S.-aiana, Pmu., Tuntelb, Vermetus. 
Sili'.juaria, MagilllB. 

\--nia, X-Tifin,], ( 'lirli-.ii, V.-lat. -i. Pjb'Liln-,. \avirc-llo, Natica. 
Ib-linna, Amj.ulbm, \li'!;!!ii;', Ki-o'.a. Pli.asrmvUa, Pb'ur-.c.'nt-. 



. Pyraiukl-.lla. 



a, Pbysa.Pbnorbi-. 
Auricula, P-'ilip.-s, T-Tiiai-'lla, 'bmin^r 
S Sucoiuea, Puliuus, Achatina, Claiisilb. 

i Pupa, Partula, illix. Yitnna, 'I cstac-th, Parmaiella. T.i jiiii.-.-l I ... 
. CryptostomC "' 
Pleurobranclius. 
Aplysia, Dolabella. 

" Sipbonaria. 



., Storoatella, Yelutina. 



Atlanta, .Spiratc-lla, Ar^onauta. 

Fissur-'lla, Finainnula, Parmophorua. 
Haliotis, Ancylus. 

(Vpidula, ( '.'.ly]>ty;iTi. 1 'apubi-. [tijijioiiyx. N->irc!iia. 

, I b t I 1 J 1 ul Crania. 

,<pli;.-ni!it.s, llipi-uril. •:■■., ( { :>• N . .1 1 1 . s . ]'. ir-.stnt.es, Calm 
An. .una, Placima, (Ktra.vi, Grypha;. 

Sp.-mdylu-. Pbraiula. 1 1 unntc.-, IVrUui, P.-dmii, Fnna 
ricula, Perna, Crenatula. 
, Pulvinites, Gervillia. 
Pinna, Mytilus. 
Area, P-rtunculus, Nucula. 
Anodon, L'nio, Cardita. 
Cliainri, I >ic-ims, Ktb.-vm, 
< Canlumi, ]>-.nax, IVllnia 
) Cyprina, Marlra, Kryriii 
I \ .■ii.'S-ii-upis, Wnus Cur: 

Lc - 

Psammocola, Sob'teltina. S;i fi-ii i m .Firiu. Sulcnocurtus. 
Solen, Solemya, Pan..pa-a, (ily..'im.-n>, iSaxicava, ByNsnrnyn. 
HI iboid--s, C.astn«L-!i...-]i:i, cia-.-a-HIa. Asp erg ilium. 



, 1 1 ipj-M-ipn- . Is-iiainliiini, "l> 



Pbolas, Teredina, Teredo, Fnstnlana, Septan 

latholepas. 

Crrmsia, Pyrpnma, 



MALENTOZOARIA J 



Gymnolepas, Pental-'pas, IVdylcpap, 
f liahmus, A casta, Octbosia, C 
\ C-.mnula, Clu'hiobia, Otiapi 



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