Family Dentaliidie

The Angled Tooth Shell (D. hexagonum, Gld.), found on the California coast, has a much more delicate shell than the more northern species. It is distinctly six-angled by ridges extending its whole length. Length, 1 inch.

The Common Tooth Shell of warm European waters is D. vulgare, Da Costa. Its slim shell averages less than two inches in length. The shell is opaque, lustreless, whitish, with tinting of rose or yellow toward the apex, and often has indistinct dusky bands crossing the fine longitudinal stria;. The aperture is circular and oblique, not notched. Jeffreys characterises this little creature as a "fastidious Pig from the herd of Epicurus, luxuriously picking out the choicest morsels with its extensile and delicate captacula." He found only shore forms of Foramin ifera in the stomachs of specimens examined.

The largest and finest shells of this species are collected on the Adriatic shores. They are sometimes over two inches long.

On the colder coasts of the Atlantic on both sides the com monest species is D. entalis, Linn. (This is identical with D. striolatum, Stimps., and Entalis striolata, Stimps.) Its shell is white, but more glossy and ivory-like than that of D.

301 The Tooth Shells vulgare. The longitudinal strix are wanting almost entirely, and distinct segmentation of the shell is often made by the lines of growth. The anterior margin is jagged, the posterior aperture

is oblique and notched on the convex side. This is the familiar tooth shell of the New England coast and of the British Isles.

The Shell (D. elephantinum, Linn.) is well named. It is curved and tapers like the tusk of an ele phant, is strong, and has the texture of ivory. Ten strong longitudinal ribs give it a corrugated surface. The usual colour is dark green, fading to white at the apex. Transversely the ridges are crossed occasionally by bands that limit the annual growth of the shell. These strikingly handsome tusk shells come from the Orient, notably from the Philippine Islands. They are sometimes three inches in length.

D.

aprinum, Linn., is a pea-green, glossy tooth shell of a slender, gracefully curving form, but strongly built. The 9 to 12 ridges are not so prominent as in the two preceding species; they are separated by wide, flat and highly polished intervals. These measure up to 21 inches in length. Diameter of aperture, i inch. They come from the Philippine Archipelago.

The Japanese angled tusk shells resemble these in form, but they are white. They are of closely related species.

302