EAST AMERICAN SCAPHOPOD MOLLUSKS. 109 



dorsal and ventral sides of the rim, leaving between them pointed 

 lateral projections. Measurements are: 



Length, 13.2 mm.; diameter, 2 by 2.5 mm.; anterior aperture, 1.75 

 mm.; apical aperture, 0.63 mm. (Dall). 



Length, 12.2 mm.; diameter, 2.11 by 2.45 mm.; anterior aperture, 

 1.2 by 1.65 mm.; apical aperture, 0.83 mm. 



Length, 12 mm.; diameter, 1.90 by 2.20 mm.; anterior aperture, 

 1.40 by 1.20 mm. (type). 



The type. Cat. No. 95374, U. S. N. M., is from a lot of two specimens 

 collected by the Blalce at United States Coast Survey Station 226, off 

 St. Vincent, in 424 fathoms, bottom of fine dark sand and tempera- 

 ture of 42.5° F. 



In the museum collection is one other lot, Cat. No. 95380, U. S. N. 

 M., consisting of a single abnormal specimen, also collected by the 

 Bl'aJce, United States Coast Survey Station not recorded, in 640 

 fathoms, off Yucatan Bank. 



CADULUS (PLATYSCHroES) AEQUALIS Dall. 



Plate 17, fig. 11. 



1881. Cadulus aequalis Dall, Bull. Mus. Comp. Zool., vol. 9, p. 34. 

 1889. Cadulus aequalis Dall, Bull. Mus. Comp. Zool., vol. 18, p. 429, pi. 27, fig. 9. 

 1889. Cadulus aequalis Dall, Bull. 37, U. S. Nat. Mus., p. 76, pi. 27, fig. 9. 

 1898. Cadulus (Gadila) aequalis, Pilsbry and Sharp, Tryon's Man. Conch., vol. 



17, p. 170, pi. 25, fig. 48. 

 1903. Cadulus aequalis Dall, Bull. 37, U. S. Nat. Mus., p. 76, pi. 27, fig. 9. 



The shell is very large and moderately curved, with scarcely any 

 perceptible sweUing; the greatest diameter lies within the anterior 

 fifth portion of the shell. The convex side curves regularly to a 

 point just back of the anterior aperture, and thence for the short 

 remaining distance to the aperture it is a straight line. The concave 

 outline is quite regular throughout ; its posterior portion perhaps show- 

 ing a slightly greater degree of curvature. The anterior aperture is 

 a ^little oblique, somewhat constricted, and almost round. The 

 apical orifice is round and relatively large. No apical features are 

 observable in the two museum specimens. 



The type, Cat. No. 95373, U.S.N.M., is from a lot of two specimens 

 taken by the BlaJce at United States Coast Survey Station 43, oft 

 Tortugas, in 339 fathoms, bottom temperature 45° F. It measures- 

 length, 15 mm.; maximum diameter, 2.5 mm.; anterior aperture, 2 



mm- ; apical aperture, 1 mm. ,,,,.* j i 



This is the unique museum record. A Philadelphia Academy ol 

 Natural Sciences specimen, collected by Commander Rush on the 

 -E coast of Florida," is apparently referable to this species. Ihe 

 species is distinguished by its lack of most of the usual features of the 

 genus. Indeed, it is a shell that might easily be mistaken lor a 

 Dentalium. 



