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North American Land Snails — Part 2

Habitat.-Jamaica.

Genus POLYGYRELLA, Binney

Shell a flat spiral, with wide umbilicus; coils seven to eight, cross-ribbed above; glassy, shining, yellowish, horn-colour; lip not expanded, thickened at edge by white rim, and armed with two or three teeth; columella bears triangular tooth.

The single species, P. polygyrella, Bland and Cooper,1/2 inch in diameter, lives in the spruce forests of the Coeur d'Alene Mountains in Idaho.

Genus PLEURODONTE, Fisch. (CAROCOLUS, Montf.)

Shell large, solid, more or less flattened; whorls four to six, rounded or keeled; lip flaring or reflexed, generally toothed. Eggs large, oval, hard-shelled; foot undivided, sides granular; mantle edge frilled.

A tropical American genus of large ground snails whose nearest relatives inhabit China, the East Indies and Australia. The genus exhibits a great variety of forms.

The Wavy Pleurodonte (P. sinuata, Mull.) has its doorway narrow and guarded by white teeth or wide and smooth-rimmed. The variation in form is from a top-shaped cone to a lens with keeled rim. There is also a wide-mouthed nerite form. Brown banded with yellow, white, wound with yellow, and unbanded shells, from chocolate to cream, indicate the range of colour. The young have shells of two and one-half whorls before hatching. Diameter, 1 to 2 inches.

Habitat.-Jamaica.

P. gigantea, Scop., is thick, brown obliquely streaked, with a white lip thickened and expanded. Diameter, 2 to 2 1/2 inches.

Habitat.-Haiti.

P. Jamaicensis, Chemn., has the nerite form, bright chestnut with pale bands, and a very thick, broad, white rim overlying the columella and outer lip. Diameter, 2 inches.

Habitat.-Jamaica.

Genus CEPOLIS, Montf.

Shell depressed, globular, smooth, umbilicate or not; lip reflexed at columella, usually thickened with callus, sometimes toothed, one-coloured or conspicuously banded; jaw high, arched; radula long.

C. cepa, Mull., has a finger-like fold of callus within the mouth, and another on the anterior margin bearing a tooth. The pale chestnut ground is banded above by spiral lines of brown. This ground snail, 1 to 1 1/2 inches in diameter, is quite dull beside the arboreal species, which are gaily coloured in both body and shell.

Habitat.-West Indies.

Genus LYSINOE, H. and A. Ads.

Shell depressed, globose, granulated or hairy; brown with spiral bands; aperture lunate; lips somewhat reflexed; body very large, coarsely granular above, tail keeled. Three species.

L. Humboldtiana, Fer., with an elevated spire and three dark bands, is a Texan species. Diameter, 1 to 2 inches. The type, however, of the genus is the larger, more flattened L. Ghiesbreghti, Nyst., with more elaborate banding-a symphony in brown-which inhabits Central America.

Genus EPIPHRAGMOPHORA, Doring (AGLAIA and ARIONTA of American authors)

Shell discoidal to globose, four to seven whorls, rarely keeled; horny to chalky; variegated and banded; lip thin, expanded or reflexed, epiphragm secreted by certain species, but not a constant character. A large genus distributed on the Pacific slopes of America.

The Faithful Snail (E. fidelis, Gray) has a low cone with rounded, smooth whorls banded with brown. Basal area of body whorl dark brown to black. The umbilicus is open, but contracted at the top by the flaring of the lip. Epidermis yellowish. Diameter, 1 to 1 1/2 inches. Late broods are often found tucked away in holes in the trunks of maple trees, far above the ground.

Habitat.-Vancouver Island to California.

E. Mormomum, Pfr., has a more flattened spire. The thin body whorl, pale reddish, with arching striae, is adorned by a chestnut band, doubly edged with white. The aperture is ear-shaped and oblique, its rim white and recurved. Diameter, 1 inch; height, 1/2 inch.

Habitat.-Mountains of California.

The Point Cypress Snail (E. Dupetithouarsi, Desh.) is lowspired, its seven brown whorls decorated with a yellow-edged, almost black median band. The body is grayish, and warty. Diameter, 3/4 inch.

Professor Keep found these snails asleep in debris under the gnarled old veteran cypresses of Monterey. They were dormant in the drought of summer, and many shells were empty, punctured by hungry jays. The living ones became quite active when put into a damp fernery, and sprinkled with water.

E. sequoicola, Coop., which lives among the red-woods near Santa Cruz, has a more elevated spire, roughened by fine ridges, and granulated about the apex.

E. Traskii, Newc., and E. Carpenteri, Newc., each wears a band of brown, edged with yellow or white, on a horn-coloured, striated surface. The latter is more delicately built throughout. Diameter, less than 1 inch.

Habitat.-Southern California.

E. Coloradoensis, Strns., is low-spired, fragile and pale, with a narrow red band. The mouth is large. It was found at a high elevation near the Grand Canon of the Colorado. Diameter, 3/4 inch.

The Dented Snail (E. arrosa, Gld.) has a more solid and elevated spire than the preceding species, with a dark band on the yellowish brown coils. The rough surface has furrows of different lengths. The pit is not covered by the reflected inner lip. Diameter, 1 1/4 inches.