EAST AMERICAN SCAPHOPOD MOLLUSKS. 



81 



in the typical subspecies. As those live in protected waters they pro- 

 serve their tips, thus appearing to be more slender. This is one of the 

 most beautiful of the smaller DenUilia, and I am glad to dedicate it to 

 the captain of the Tomas Barrera, Gaspar PoUicer. 



The type, Cat. No. 314565, U.S.N.M., was dredged in the harbor of 

 Bahia Honda, Cuba in 1 to 12 fathoms. It measures — length, 11.5 

 mm.; diameter, 0.9 mm.; tip preserved. 



Another specimen from the same lot with tip lost, but with a pro- 

 jecting "pipe", measure — length, 14.5 mm., diameter, 0.95 mm. 

 There are in the National Museum collection eight lots from within 

 the Colorados Reefs, Cuba; one from off Sand Key, Florida, 65 fath- 

 oms; and one from Cape Catocho, Yucatan, in 25 fathoms. 



The folio wins are the National Museum records: 



Subgenus BATHOXIPHUS Pilsbry and Sharp, 1897. 

 1897. Bathoxiphus Pilsbry and Sharp, Tryon'sMan. Conch., vol. 16, p. 121. 



The shell is thin, conspicuously compressed laterally and nearly 

 smooth; it has a broad apical slit on the convex side. 



Lateral compression, at least w^hen carried to a noticeable degree, is 

 very unusual among the Dentalia. The subgenus contains but two 

 well-defined species and a possible third. 



KEY TO THE SPECIES OF THE SUBGENUS BATHOXIPHUS. 



Keeled on both convex and concave sides ensiculus, page 81. 



Keeled on convex side only didymum, page 83. 



DENTALIUM (BATHOXIPHUS) ENSICULUS Jeffreys. 



Plate 14, figs. 1, 4, 5, 7, 9. 



1877. DentaUum ensicnlus Jeffreys, Ann. and Mag. Nat. Hist., ser. 4, vol. 19, 

 p. 154. 



1881. DentaUum sijsbeaHum Dall, Bull. Mus. Comp. Zool., vol. 9, p. 38. 



1882. DentaUum ensiculus Jeffreys, Proc. Zool. Soc, p. 660, pi. 49, fig. 4. 

 1885. DentaUum ensiculus, Watson, Challeiyjer Report (Scaphopoda), p. 12, pi. 



2, fig. 2. 

 1885. DentaUum ensiculus, Verrill, Trans. Conn. Acad, of Arts and Sci., vol. 6, 

 p. 4.32. 



