A Conchological Manual by George Brettingham Sowerby (best interesting books to read txt) 📕

   which breath water, marine or fresh-water molluscs. Fig. 227 to 263.

GASTRANEA. Schum.? CORBULA, Auct.

   GASTROCHÆNA. Speng. ([Greek: Gastêr], _gaster_, belly; [Greek: chaino],

   _chaino_, gape.) _Fam._ Pholadaria, Lam. Pyloridea, Bl.--_Descr._

   Equivalve, 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 Clavagella, in

   both valves being free.--_Obs._ The Gastrochænæ 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, probably 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 whorls. Helix

   bicarinata, Sow. Zool. Journ. 1, pl. 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), consisting of oval

   species, resembling Auricula Midæ, 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 approaches 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. Méth. 374, f. 6."

   GIBBOSE or GIBBOUS. (_Gibbosus._) Bunched out, embossed, having a lump

   or swelling of any kind. _Ex._ Bulinus Lyonetianus, (fig. 284.) named

   Gibbus by De Montfort. Ovulum gibbosum.

   GIBBUS. Montf. BULINUS _Lyonetianus_, Lam. PUPA, Bl. fig. 284.

   GIOENIA. A name given in the Encyclopédie Méthodique, 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 or oval,

   transverse, slightly ventricose, equivalve, inequilateral; margins

   close, rounded anteriorly, somewhat acuminated posteriorly; hinge

   teeth, three in each valve, of which the central in one, and the

   posterior in the other, are bifid; muscular impressions anterior,

   elongated, marginal; posterior sub-quadrate; palleal impression, having

   a long sinus; ligament oblong, external; 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. _Fam._ 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. ([Greek: Gnathos], _gnathos_, jaw-bone; [Greek: odos],

   [Greek: odontos], _odontos_, tooth.) _Fam._ Mactracea, Lam.--_Descr._

   Ovate, posteriorly angulated, equivalve, thick, ventricose,

   inequilateral, covered with a greenish brown epidermis; umbo distant,

   prominent; 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 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.

   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. pl. 5, f. 2." Sw. p. 335.

   GONIOSTOMATÆ. Bl. A family belonging to the order Asiphonibranchiata,

   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, _Desh._ Lesson, Voy. pl. 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.--_Descr._ 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 umbones, 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.

   GRYPHÆA. Lam. (From Gryps, a griffin.) _Fam._ Ostracea, Lam.--_Descr._

   Inequivalve, free; lower valve large, concave; with the umbo 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 Gryphæa.

   GYMNOLEPAS. A generic name used by De Blainville to include OTION and

   CINERAS, Leach.

   GYMNOSOMATA. Bl. The second family of the order Aporobranchiata, 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.

   HALIOTIDÆ. Sw. A sub-genus of Calyptræa. CALYPTRÆA dilatata. Sowerby's

   Genera of Shells, fig. 9.

   HALIOTIS. Auct. ([Greek: als], _als_, sea; [Greek: ous], [Greek: ôtos],

   _otos_, ear.) _Fam._ Macrostomata, Lam. Otides, Bl.--_Descr._ Auriform,

   broad, depressed, pearly within, rough, costated, tuberculated without;

   spire short, flat, consisting of one or two whorls; aperture wide;

   ovate; columella laminar, flat, oblique; a spiral series of

   perforations 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 [Greek: eidos], _eidos_, form.) Ear-shaped.

   HAMIFORM. (_Hamus_, a hook.) Curved at the extremity.

   HAMITES. Parkinson. (_Hamus_, a hook.) _Fam._ Ammonacea, 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-Marle, 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, reflected, 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 confounding it with any other. H. multicostata,

   (Buccinum costatum, 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 longitudinally 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, 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 NUMMULITES, Lam. ROTALITES 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.