_Fam._ Limacineæ, Bl. _Gen._ POLYPHEMUS, Montf.--_Descr._ 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 Achatinæ 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.
Polyphemus Glans, fig. 288. These land shells are found in various
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. Sandwich 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; [Greek: Desma], _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 destitute of the
hinge ligament. The action of opening and shutting 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 belonging to the
family of Unionidæ, 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
distinctions, 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 ligament.
ÆGLIA. Say. A division of "Unionidæ," described as having the "shell
cuneate; bosses prominent; cardinal teeth much compressed, placed on
one side of the bosses. Æglia ovata, _Say_. Occidens _Lea_. Am. Tr.
iii. pl. 10." Lardner's Encyclopedia of Malacology.
AGANIDES. Montf. ORBULITES, Lam.
AGATHIRSES. Montf. SILIQUARIA, Auct.
AGINA ----? Belongs to SAXICAVA, Auct.
AKERA. Bl. The fourth family of the order Monopleurobranchiata, Bl.
containing the genera Bulla, Bullæa and Bellerophon, which, excepting
the last, constitutes the family Bullæana, Lam.
AKERA. A genus of extremely light, horny shells, resembling BULLA, from
which it differs, in the outer lip being separated from the body whorl,
which is elastic. _Ex._ Bulla fragilis, fig. 247.
ALÆA. 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. consisting of those
species which have cardinal, but no lateral teeth. _Ex._ A.
complanatus, fig. 141. North America and Europe.
ALATÆ. Lam. A family of the order Trachelipoda, Lam. containing the
following genera which may be thus distinguished.
1. ROSTELLARIA. Sinus close to the canal; including _Hippochrenes_,
and _Aporrhais_, Fig. 402 to 404.
2. STROMBUS. 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) Helicinæ which have a notch in the
aperture. A distinction which it is impossible to maintain. See
HELICINA.
ALATUS. Humphrey. STROMBUS, 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 aperture. It belongs to
the family Ammonacea, Lam.
AMARULA ----? A genus composed of MELANIA Amarula, Auct. and similar
species.
AMBIGUÆ. 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 amiculatus, Auct.
the valves of which are covered by an integument; so as to be
completely hidden externally.
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 distinguish 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, Icthyosarcolites, and other genera mentioned
in the list of figures 477 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, or AMMONOCERATITES. Lam. (from _Ammon_ & [Greek: Keras],
ceras, horn.) The shells described under this Lamarckian genus present
an anomaly which is considered by 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 ----? The same as AMPULLARIA, Auct.
AMPHIBULIMA. 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 abandoned by its author, and
the species stands in his system as Succinea cucullata. West Indies.
AMPHIDESMA. Lam. (from [Greek: Amphô], _ampho_, _ambo_, [Greek:
Desmos], _desmos_, _ligamentum_). _Fam._ Mactracea, Lam.--_Descr._
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 excavation 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 Lutrariæ gape anteriorly. The species
do not appear to be numerous, no fossil species are known. A.
_Reticulatum_, 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 chambers by
numerous transverse septa, which embrace each other with reflected
margins. It occurs in the Dublin limestone, and resembles 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._ "Peristomiens,"
Lam. Ellipsostomata, Bl.--_Descr._ Spiral, globular, sometimes
discoidal, frequently umbilicated, covered with a rounded, horny
epidermis; spire short; whorls rapidly enlarging; aperture 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 distinguished 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
Ampullaria 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 respiratory
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.
AMPULLARINA ----? 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.
ANASTOMA or ANOSTOMA. Fischer. (from [Greek: Ana], _ana_, backwards;
[Greek: Stoma], _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 upwards, 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 Montfort'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 Barnacles, 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 ciliæ 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
PENTELASMIS; and fig. 34.
ANATINA. Lam. (_That which belongs to a duck._) _Fam._ Myaria, Lam.
Pyloridea, Bl.--_Descr._ Thin, transparent, generally equivalve,
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 Næara, Gray, is
composed of Anatina longirostrum, and similar species, which have
neither the bony appendage nor the spoon-shaped prominence. Mya is
distinguished from Anatina, by the thickness of the shell, and also by
having the prominence only in the hinge of one valve. Fig. 69. A.
rostrata. The Anatinæ 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._ convolutæ, Lam.
Angyostomata, Bl.--_Descr._ Smooth, oblong, subcylindrical. Spire
short, sutures hidden by enamel. Aperture long, anteriorly emarginated
and somewhat effuse. Columella tortuous, oblique, tumid,
truncated.--_Obs._ The Ancillariæ 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
grossièr 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. cinnamonea, 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 examination of the different species,
however, it will be found that this is quite unsatisfactory, as a
generic distinction; because some of 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
Lymneanæ. 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 CONVOLUTÆ of Lamarck.
ANNELIDES. The ninth class of invertebrated animals, divided into three
orders, namely, A. Apodes, A. Antennés, and A. Sedentaires. 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.
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, inequivalve,
sub-equilateral, 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 Linnæan genus included 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 perfectly distinct. The Anomiæ 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. 188, 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
Ancylus, 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. If the ligament be placed only on one side
of the umbones, it is only on the 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 ciliæ 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 successor, 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 indicated 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 described, as follows:
The inner lip or labium is that part which lies over the preceding
whorl of the shell. It terminates anteriorly, or towards the lower part
in what is termed the columella, 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 composing the peritrême. In fig. 318, the aperture is marked by the
letter a.