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The tusk-like shell is generally swollen in the middle and is entirely smooth. The foot is worm-like and can be expanded at the end into a round disk. The median tooth of the radula is almost as long as wide.

Shell small, white, without sculpture and swollen in the middle somewhat like a cucumber. Aperture constricted and very oblique. The genus is divided into four subgenera as follows:

Apex with 2 deep slits Dischides ]t&.vtys i^6-]

Apex with 4 deep slits Polyschides Pilsbry and Sharp 1897

Apex with 2 or 4 shallow slits Platyschides Henderson 1920 Apex without slits:

Obese, convex on both sides Cadulus s. str.

Slender, almost flat on one side Gadila Gray 1847

Cadulus carolinensis Bush

Figure 69a

North Carolina to Florida and to Texas.

10 mm. in length. Slightly swollen. Apex with 4 shallow slits. In cross-section the shell is roundish. Commonly dredged from 3 to 100 fathoms.