Part 10

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

_P. carinatus._ The keeled Planorbis.

Species with a keel; depressed, upper side concave.

_P. corneus._ The horny Planorbis. Pl. 20, fig. 4.

Species without a keel.

2. Physa. Four species.

This genus is generally heterostrophe (that is, with whorls turned to the left hand); found in fresh water; it greatly resembles the Lymnæa, but has not a widened aperture.

Shell often sinistral, oval, oblong, or globular, perfectly smooth; aperture oval, contracted posteriorly; the right edge sharp, advanced above the plane of the left edge; columella twisting obliquely, and enlarging to join itself to the anterior part of the columellar margin.

Physa castanea. P. fontinalis. P. hypnorum. P. subopaca.

_P. fontinalis._ The fountain Physa. Pl. 20, fig. 2.

Volutions reversed, oval, ventricose, pellucid, horn-coloured; spire short and acute.

3. Lymnæa. Eleven species.

Shell aquatic, oval, turreted or conical, thin, smooth, spire pointed; aperture oval, entire; edges disunited, the left with a very oblique plait at the point of junction of the columella with the rest of the margin.

Lymnæa stagnalis. L. palustris. L. Virginiana. L. luteola. L. acuminata. L. auricularia. L. ovata. L. peregra. L. intermedia. L. leucostoma. L. minuta.

_L. stagnalis._ The pond Lymnæa. Pl. 20, fig. 1.

Ovate, ventricose; spire subulate and very acute; aperture large and ovate; horn coloured.

_L. leucostoma._ The shining Lymnæa.

Species sub-turreted, with the right edge thickened.

FAMILY IX. MELANIDES. Three genera.

1. Melania. Sixteen species.

Likewise taken from the Helix of Linnæus.

Shell fluviatile, covered with epidermis, oval, oblong; spire slightly pointed, more or less turreted; the margin of the whorls often surmounted by spires; aperture oval, entire; columella smooth and arched; closed by a thin, horny, complete operculum.

Melania asperata. M. truncata. M. coarctata. M. punctata. M. corrugata. M. subulata. M. lævigata. M. clavus. M. decollata. M. amarula. M. thiarella. M. spinulosa. M. granifera. M. carinifera. M. truncatula. M. fasciolata.

_M. amarula._ The crowned Melania. Pl. 20, fig. 3.

Covered with a black epidermis, under which the colour is deep chestnut; ovate oblong, with the whorls transversely keeled and coronated with triangular tubercles, from which emanate ciliated spines.

2. Melanopsis. Three species.

The shells of this genus are fluviatile, and distinguished from the Melania by having the upper part of the columella callous.

Shell oval or slightly sub-turriculated; aperture oval, without trace of tube, but hollowed anteriorly, without a posterior sinus; the columellar edge callous and rather deeply excavated; operculum horny, sub-spiral, rather complete.

Melanopsis Buccinoides. M. costata. M. lævigata.

_M. Buccinoides._ The Buccinum-shaped Melanopsis. Pl. 20, fig. 6.

Species turriculated; colour bluish white, clouded with purple; spiral whorls dentated.

_M. costata._ The ribbed Melanopsis.

Species sub-turriculated and ribbed.

_M. lævigata._ The polished Melanopsis.

Species ovate, smooth, chestnut colour.

3. Pirena. Four species.

This shell resembles the Melania, but is easily distinguished by having a sinus at the base and another at the summit.

Shell turreted, aperture oblong, closed by a horny operculum; right lip sharp, with a distinct sinus at the base and another at the summit; base of the columella inclined towards the right.

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

_P. terebralis._ The wimble Pirena.

Subulate, longitudinally striated, covered with a dark-brown epidermis; aperture white, outer lip expanded.

FAMILY X. PERISTOMIDES. Three genera.

1. Valvata. One species.

This genus contains shells found in fresh water. Shell sub-discoid or conoid, umbilicated, spiral whorls rounded; summit papillose; aperture round, not modified by the last whorl; the edges completely united, sharp; operculum complete, horny, and orbicular.

_V. piscinalis._ The Pond Valvata. Pl. 20, fig. 5.

Small, globular, conoid, deeply umbilicated; summit obtuse; wrinkled longitudinally, covered with a yellowish epidermis.

2. Paludina. Seven species.

Generally inhabits fresh water, though some have been found where it is quite saline.

Shell conoid, covered with epidermis, spiral whorls rounded; rather longer than broad, edges united, always sharp; the commencement of the left edge immediately attached to the last whorl of the spire; operculum horny, complete, or marginal, not spiral, with concentral elements.

Paludina vivipara. P. achatina. P. Bengalensis. P. unicolor. P. impura. P. muriatica. P. viridis.

_P. vivipara._ The viviparous Paludina. Pl. 21, fig. 1.

Thin, ovate, ventricose, wrinkled longitudinally; body with three brown bands: covered with a greenish epidermis; aperture almost round.

3. Ampullaria. Eleven species.

This genus is evidently intermediary to the Paludina and the Natica. Its species are probably all fluviatile; some attain a great size.

Shell thin, globular, ventricose; umbilicus small, forming a compressed funnel-shaped aperture, without interior callosity; spire very short, the last whorl much larger than all the others together; aperture ovate, longer than broad, with margins united; right margin smooth and sharp; columellar lip thickened, projecting, and reflected over the umbilicus; operculum horny, rarely calcareous, thin, oval, not spiral, with concentric elements; summit sub-marginal, inferior, passing obliquely by the right edge of the aperture, but attached to the left.

Ampullaria Guyanensis. A. rugosa. A. fasciata. A. canaliculata. A. effusa. A. Guinaica. A. virens. A. carinata. A. avellana. A. intorta. A. fragilis.

_A. Guyanensis._ The Guiana Ampullaria.

Globular, thick, with unequal longitudinal striæ; covered with brown epidermis; inside golden colour.

_A. rugosa._ The rough Ampullaria. Pl. 21, fig. 3.

Species dextral.

_A. Guinaica._ The Guinea Ampullaria.

Species sinistral.

_A. carinata._ The carinated Ampullaria.

Species sinistral, with a very large umbilicus, spirally carinated.

FAMILY XI. NERITACEA. Five genera.

1. Neritina. Twenty-one species.

Formerly classed with the Nerita, but separated from it because the Nerita is a marine shell, and those of this genus are fluviatile.

They are generally thin, smooth, or very finely striated; the right side of the aperture is not crenulated or dentated, and the animal dissolves the interior of the spire.

Shell thin, ovate, not umbilicated; aperture semilunar; inner lip reflected on the columella, and sometimes crenated; outer lip without teeth internally; operculum with a lateral tooth.

Neritina perversa. N. pulligera. N. dubia. N. zebra. N. zigzag. N. gagates. N. lugubris. N. corona. N. brevispina. N. crepidularia. N. auriculata. N. Domingensis. N. fasciata. N. lineolata. N. semi-conica. N. strigilata. N. meleagris. N. Virginea. N. fluviatilis. N. viridis. N. Bætica.

_N. fluviatilis._ The fresh-water Neritina.

Shell very small, oval; back convex, smooth, white, with black or brown spots; spire inclined, lateral lip slightly denticulated; right edge sharp, operculum very oblique.

_N. zebra._ The zebra or striped Neritina. Pl. 21, fig. 2.

Same as N. fluviatilis, but striped instead of spotted.

_N. corona._ The crown Neritina. Pl. 21, fig. 4.

Species provided with long spines, and with the columellar edge denticulated.

_N. auriculata._ The eared Neritina.

Species with the columellar edge denticulated; the two extremities of the right edge extending beyond the aperture, and forming with the callosity, which is reflected over the columella, a kind or ear, produced by the tentacular lobe of the animal.

_N. perversa._ The perverse Neritina.

Species shaped like a Calyptræa, with the superior summit vertical, spiral; the last whorl forming all the base of the shell.

2. Navicella. Three species.

A fresh-water shell, closely allied to the Neritina; it generally has the appearance of porcelain.

Shell ovate oblong, covered with epidermis, shaped like a Patella, summit not spiral, but straight, turned quite to the base, and concave beneath; no columella; the columellar edge replaced by a kind of sharp partition, which covers part of the aperture, with a sinus at its left extremity; muscular impression shaped like a horseshoe, open in front and interrupted behind; thin, calcareous operculum, with a subulate, lateral tooth adhering to the posterior margin; the other edges sharp.

Navicella elliptica. N. lineata. N. tessellata.

_N. elliptica._ The oval Navicella.

Shell covered with olive epidermis, under which it is smooth, shining, spotted and streaked with purple, blue, or brown; spire curved, prominent, extending beyond the margin.

3. Nerita. The Hoof Shell. Seventeen species.

A marine shell, never spined, but variously striated. Some species of this genus are very beautiful; they are frequently worn as ornaments by the Indians.

Shell solid, thick, more or less globular, flat beneath, spire but little, if at all, projecting, not umbilicated; aperture large, semilunar, very entire; the external margin very much hollowed; the internal or columellar straight, sharp, and shaped like a partition, often dentated; operculum horny or calcareous, sub-spiral; the summit entirely marginal at its extremity, implanted by teeth more or less marked, and sunk in the columellar margin, on which it seems articulated.

Nerita exuvia. N. textilis. N. undata. N. peloronta. N. chlorostoma. N. atrata. N. polita. N. albicilla. N. chamæleon. N. versicolor. N. Ascensionis. N. Malaccensis. N. lineata. N. scabricosta. N. plicata. N. tessellata. N. signata.

_N. peloronta._ The bleeding-tooth Nerita. Pl. 21, fig. 5.

Thick, transversely sulcated; inner lip with two crenulations, with a bloody mark at their base; under lip with two notches near its internal upper edge; colour yellowish, tinged with red, with variously coloured bands.

_N. exuvia._ The exuvia Nerita.

Species with the inner lip toothed and tuberculated.

_N. polita._ The smooth Nerita.

Species with both lips toothed; beautifully distinguished by having three or four bright crimson bands, on a dark mottled ground, running in a parallel direction with the convolutions of the shell. A favourite Indian ornament.

4. Natica. Thirty-one species.

A marine shell, formerly classed with the Nerita, but distinguished by being without teeth, and having an umbilicus modified by the callosity.

Shell smooth, rather thin, and not covered with epidermis; the spire evident, though low, umbilicated; the columellar edge not toothed, more or less callous, modifying the umbilicus; the right edge thin and not toothed interiorly; operculum calcareous or horny and smooth, semi-spiral, with concentric ribs fitting into a slight groove on the columella.

Natica glaucina. N. albumen. N. mamillaris. N. mamilla. N. ampullaria. N. canrena. N. cruentata. N. millepunctata. N. vitellus. N. helvacea. N. collaria. N. monilifera. N. labrella. N. rufa. N. uni-fasciata. N. melanostoma. N. aurantia. N. conica. N. plumbea. N. lineata. N. fulminea. N. maculosa. N. vittata. N. castanea. N. Marochiensis. N. arachnoidea. N. zebra. N. zonaria. N. Chinensis. N. Javanica. N. cancellata.

_N. canrena._ The Canrena Natica.

Sub-globular, smooth, umbilicus deep, bordered anteriorly by a kind of callous column; spire a little prominent; exterior fawn coloured, with bands and rays of reddish brown; interior white; operculum calcareous.

_N. castanea._ The chestnut Natica. Pl. 21, fig. 6.

Species with the umbilicus uncovered, and the operculum horny.

_N. mamilla._ The nipple Natica.

Species with the umbilicus entirely covered over by a large callosity; the spire papillose, and the operculum horny.

5. Janthina. Two species.

Formerly classed with the Helix, which it somewhat resembles in form, but properly separated, as it differs in every other respect.

It is a singular marine shell, often found in great numbers floating on the surface of the sea, suspended by a vesicular appendage, which stains the hand of a purple colour.

Shell sub-globular, ventricose, extremely thin and fragile; transparent, of a beautiful violet colour; the spire low, lateral, pointed, with sub-carinated whorls; aperture large, sub-angular, greatly modified by the last whorl of the spire; edges disunited, the left entirely formed by the columella, which is straight and continued beyond the base, the right edge sharp, often with a sinus in the middle.

Janthina communis. Janthina exigua.

_J. communis._ The common Janthina. Pl. 18, fig. 6.

Very fragile, aperture triangular, with a small notch on the margin of the outer lip; beautiful violet colour.

FAMILY XII. MACROSTOMIDES. Four genera.

1. Sigaretus. Four species.

Distinguished from the Natica by the great width of the aperture, and its short spiral columella.

Shell oval, more or less thick, very depressed, spiral short, little elevated, lateral; aperture very extended, entire, the left edge reflected and sharp; two lateral muscular impressions very disunited.

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

_S. convexus._ The convex Sigaretus. Pl. 22, fig. 2.

Very thin, smooth, back convex, spire white, rather prominent; aperture very expanded; umbilicus rather deep; yellow, with a reddish tinge, transversely striated.

_S. Haliotoideus._ The Haliotis-shaped Sigaretus.

Species thick, solid, depressed; spire flattish, aperture exposing the whole of the interior.

2. Stomatella. Five species.

To be easily distinguished from the Stomatia by not having a transversal rib.

Shell very depressed, orbicular or oblong; imperforate; interior pearly; aperture very large, oval, longer than wide; the right edge effuse, dilated, and open; summit pointed and incurved.

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

_S. imbricata._ The imbricated Stomatella. Pl. 22, fig. 1.

Sub-orbicular, convex, sub-depressed, rough, covered with imbricated scales; colour grayish brown.

_S. auricula._ The ear-shaped Stomatella.

Species oval, elongated.

3. Stomatia. Two species.

Bearing a very great resemblance to the Haliotis, but is never perforated.

Shell ear-shaped, imperforate; oblong, spire elevated and recurved to one side; aperture entire, oblong; interior pearly; tuberculated, and with a transverse sub-carinated rib.

_S. phymotis._ The tumoured Stomatia. Pl. 22, fig. 6.

Elongated oval, striated, tuberculated; spire small, contorted; lip thin and sharp, colour white, interior pearly.

4. Haliotis. The Ear Shell. Fifteen species.

This genus is very beautiful, and derived its common name from its resemblance to the human ear. The exterior is generally tuberculated and loaded with marine substances, which gives it a rough and uncouth appearance, but the interior forms a splendid contrast by its natural iridescence. Each shell is furnished with a row of orifices near the margin, varying in number from eight upward; of these from three to seven are generally open, and the others close. These holes are made by the animal as it increases the size of the shell, to admit the passage of a short syphon.

They are found adhering to rocks like the Patella, and are detached with great difficulty.

Shell ear-shaped, pearly, recurving, very depressed, more or less oval, with spire very small, very low, almost posterior and lateral; aperture as large as the shell, with margins continued; the right thin and sharp, the left flat, enlarged, and sharp; a series of holes, complete or incomplete, parallel to the left margin; one large oval muscular impression.

Haliotis Midæ. H. iris. H. tubifera. H. excavata. H. Australis. H. tuberculata. H. striata. H. asinina. H. glabra. H. lamellosa. H. unilateralis. H. rugosa. H. canaliculata. H. tricostalis. H. dubia.

_H. asinina._ The asinine Haliotis.

Internal margin very broad, inside pearly, smooth, shining, iridescent, reflecting green, pink, and orange; back clouded with brown and green; striated longitudinally.

_H. costata._ The ribbed Haliotis. Pl. 22, fig. 4, interior. Pl. 32, fig. 6, exterior.

Species with disk rounded anteriorly.

_H. canaliculata._ The channelled Haliotis.

Species with disk elevated by a large parallel rib, hollowed interiorly, and with the anterior margin more or less irregular.

_H. tuberculata._ The tuberculated Haliotis.

Aperture open the whole length of the shell; outer lip irregular, exterior reddish brown, striated longitudinally and wrinkled transversely, with a few raised tubercles; interior pearly, reflecting the most beautiful shades of pink, blue, green, and yellow.

FAMILY XIII. PLICACEA. Two genera.

1. Tornatella. Six species.

Shell thick, oval, convolute, the spire very short; the last whorl much larger than all the others united; the external thin, sharp, dentated interiorly; one or two large plaits on the columella, of which one serves to separate the two parts of the foot.

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

_T. fasciata._ The banded Tornatella.

Spire produced, apex acute, aperture straightened, with one plait on the columella; finely striated transversely, with two white transverse bands; colour purplish red.

_T. coniformis._ The cone-shaped Tornatella. Pl. 22, fig. 3.

Species like a cone; the spire entirely flat.

2. Pyramidella. Five species.

Shell smooth, not covered with epidermis, conical, elongated or sub-turriculated; aperture semi-oval, entire; the outer lip sharp, dentated interiorly, plaited, enlarged over the umbilicus, which it leaves more or less exposed.

Pyramidella terebellum. P. dolabrata. P. plicata. P. corrugata. P. maculosa.

_P. dolabrata._ The dentated Pyramidella. Pl. 22, fig. 5.

Answers to the above description; when placed on its base, it falls on one side.

_P. terebellum._ The wimble Pyramidella.

Smooth, glossy, white, with reddish-brown bands; columella recurved; inside of the lip smooth.

FAMILY XIV. SCALARIDES. Three genera.

1. Vermetus. One species.

Resembling in appearance the shell of a Serpula; but the organization of the animal caused this to be made a distinct genus.

Its shells are usually found grouped together or intertwined with each other, and are very remarkable for being attached to marine bodies by the attenuated and pointed extremity of the spire.

Shell conical, tubular, thin, involute spirally, more or less close, with whorls almost completely disunited; free or adherent by intertwining; aperture straight, circular, with edges sharp and complete; several partitions not perforated towards the summit; operculum horny and complete.

_V. lumbricales._ The wormlike Vermetus. Pl. 23, fig. 3.

A flexuous shell, with a spiral, acute tip, very much resembling a corkscrew; colour reddish brown, sometimes clouded with a darker shade.

2. Scalaria. Seven species.

A marine shell, with a circular aperture like the Cyclostoma, but easily distinguished by its turreted form; longitudinal, elevated ribs, never connected together, rather oblique, and sharp; the shape of the shell is elegant, being a spiral cone, formed by gibbous whorls, unconnected by a columella, gradually increasing from the apex to the base. The colour is generally yellowish or brownish white. When perfect and of good size, they are of great value and highly prized.