69 



deep slits, forming four teeth, a large dorsal and a large ventral tooth, with smaller lateral 

 ones between. 



Length 12 mill., diam. of apert. 1,25, dorso-ventral diam. of apex 0,5, lateral diam. ofaj^exo,;. 

 Breadth of greatest inflation 1,5 mill. 



Section Gadila Gray 1847. 



1847. Gadila Gray, Proc. Zool. Soc. p. 159. For D. gadtis Montagu. 

 1865. Helonyx Stimpson, Amer. Journ. Conch. I, p. 63. 



Gadiis of some authors. Dentaliuin sp. of some early authors. 



Shell decidedly curved, the general contour convex ventrally, concave dorsally; more or 

 less swollen near the middle or toward the aperture, more tapering toward the apex ; apical 

 orifice not contracted by a callous ring, or with the callus far within and weak ; edges not slit. 

 Type C. gadus Montagu. 



This group which includes a great majority of the species of the genus is more attenuated 

 and more bent than typical Cadulus, and lacks the apical slits and teeth of DiscJiides and 

 Polyschides. (P. & Sh.). 



Key to species. 



I. Length not exceeding 4 mill C. simillimus. 



IL Longer than 4 mill. 



a. The greatest diam. situated near the anterior third or fourth of the 

 shell's length. 

 b. Shell considerably swollen. 



C. gadtcs, euloides, clavaUis. colubridens^ virginalis and psezidolivi. 

 b' . Shell but little swollen and very gradually tapering toward both sides. 



C. anguidens^ zonatiis and pulcherrimtts. 

 a . The greatest diam. situated near the anterior aperture. 



C. shigaporcusis, abrupto-inflatus and lacvis. 



■*i5. Cadtihis simillimus Watson. PI. Ill, fig. 46. 



1879. Cadidus simillimus Watson, Journ. Linn. Soc, vol. XIV, p. 526. 

 18S5. Cadnlus similliinns Watson, Challenger Rep. p. 20, pi. 3, fig. 6. 



1897. Cadnlus siinillimus Watson. PiLSBRY & SHARP, Man. of Conch, vol. XVII, p. 182, 

 pi. 26, fig. yy. 



Diagnosis. Shell very like Cadttbis gracilis Jeffr., rather broad, narrowed at both 

 ends, very slightly and symmetrically bent, but a little more towards the mouth, with a very 

 slight bulge, which just shows on the concave curve. It is thin, polished, translucent (weathering 

 opaque), with an opaque ring near the apex. Sculpture : very minute and faint and superficial 

 oblique striae, with a faint flocculence in the substance of the .shell. Mouth rather large, oblique; 



