A Conchological Manual by George Brettingham Sowerby (early reader books .txt) 📖
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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, _Helicophanta_,
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 Hæmastoma, H. Contusa, (Streptaxis, 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_, Carocolla, 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 aperture, like the Helicogenæ, but with the whorls increasing
very gradually; H. epistylium. _S. gen. 8_, _Cochlostyla_, Bulinus. _S.
gen. 9_, _Cochlitoma_, Achatina. _S. gen. 10_, _Cochlicopa_, Polyphemus
Glans. _S. gen. 11_, _Cochlicella_, 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 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 Helicolimax in the
structure of the animal. Fig. 262.
HEMICARDIUM. Cuv. ([Greek: hêmisus], _hemisus_, half, [Greek: Kardia],
_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 Asiphonibranchiata, 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 Linnæus, and
to the family Neritacea of Lamarck. It contains the genera Natica,
Nerita, Neritina, and Navicella.
HEMIMACTRA. Sw. A sub-genus of Mactra, thus described: "General form of
_Mactra_; but the cardinal teeth entirely wanting; cartilage internal,
central, in a large triangular cavity; lateral teeth 2/1, distinct,
lateral, striated: connected to the _Glycimeri_. H. gigantea, _Lam._ v.
No. 1. grandis, _Sw._ Sp. Nov." Sw. p. 369.
HEMIMITRA. Sw. A sub-genus of Paludomus, Sw. (Melanianæ.)
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 contracted 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 forming an internal
groove. H. tricostata, _Sw._ Sow. Gen. fig. 6."
HEMITROCHUS. Sw. A sub-genus of Geotrochus, Sw. H. hæmastoma. Sw. p.
331.
HEPTALASMIS. Leach. ([Greek: Hêpta], _hepta_, seven; [Greek: elasma],
_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 Paracephalophora, Bl. divided
into, Sect. 1, _symmetrical_, containing the orders Cirrobranchiata and
Cervicobranchiata; Sect. 2, _non-symmetrical_, 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 Acephalophora, 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 Foraminifera.
HIATELLA. Daud. Fam. Lithophagidæ, Lam. A genus composed 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._ O. Subulata, fig. 458.
HIBOLITHES. Montf. A genus composed of species of Belemnites, 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, including 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, resembling
Isocardia in form, but destitute of hinge teeth. H. Isocardioides, fig.
128.
HIPPOCHRENES. Montf. Species of ROSTELLARIA, Auct. with the outer lip
spread. Fig. 403. R. Columbaria.
HIPPONYX. ([Greek: Hippos], _hippos_, horse; [Greek: onux], _onyx_,
nail or hoof.) _Fam._ Rudistes, Lam.--_Descr._ Inequivalve,
sub-equilateral, rather irregular, destitute of ligament and hinge
teeth; lower valve attached, flat, sub-orbicular, with a muscular
impression, composed 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
marginal.--_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 numerous, 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.--_Descr._ Equivalve,
obliquely transverse, heavy, deep, inequilateral, umbones 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.
HIPPOPUS. Lam. ([Greek: Hippos], hippus; [Greek: pous], _pous_, foot.)
_Fam._ Tridacnacea, Lam.--_Descr._ Equivalve, inequilateral, regular,
subquadrate; 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, external.--_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._
Tabular, rude, irregular, attached; lower valve cylindrical, 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 operculum.--_Obs._ This genus is
known only in a fossil state, and but very imperfectly. Lamarck places
it among his chambered Cephalopoda, &c. De Blainville, considering it a
true Bivalve, enumerates it among his Rudistes. Cretaceous group. Fig.
198, H. Cornucopia.
HORTOLUS. Montf. SPIROLINA, Lam. Microscopic.
HYALÆA. 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 more flat; lower extremity
tridentate.--_Obs._ The singular structures 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
Hyalæa occurs in Sicily in a fossil state. Recent species are found in
the Mediterranean, Atlantic, and Indian Oceans. Fig. 226, H.
Tridentata.
HYALINA, Studer. VITRINA, Drap.
HYALINE. (_Hyalus_, glass.) Glassy, thin, transparent--_Ex._ Carinaria
Mediterranea, fig. 488.
HYDROBRANCHIATA. Bl. The first section of the order Gasteropoda, Lam.
containing Molluscs which breathe water only; divided into the families
Tritoniana, Phyllidiana, Semi-phyllidiana, Calyptracea, Bullæana, 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, distinguished by
their alated dorsal margins, and lamellated lateral teeth. South
America. HYRIA corrugata, fig. 143, Hyria Syrmatophora, fig. 144.
HYRIDELLA. Sw. A genus of "Hyrianæ," 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 plicæ or calli on each side of the ligamentary pit. _Ex._ P.
plica, fig. 172. Decadopecten, Rüppell.
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, contiguous 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 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, triangular;
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 laminæ 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._
Imperialis. Some of the shells named Imperator in the British Museumbelong 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 symmetrical
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.
INEQUILATERAL. (_Æquus_,
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