1921] NATURAL SCIENCES OF PHILADELPHIA. 401 



Cadulus elegantissimus Pilsbry and Sharp. 



Cadulus elegantissimus P. and S., Proc. A. N. S. Phila., 1897, p. 473, pi. 11, 

 figs. 28, 29, 30. 



Type no. 2885 A. N. S. P. 



Cadulus depressicollis PUsbry and Sharp. 



Cadulus depressicollis P. and S., Proc. A. N. S. Phila., 1897, p. 473, pi. 11, figs. 

 25, 26, 27. 



Type no. 2884 A. N. S. P. 



Cadulus colobus Pilsbry and Sharp. 



Cadulus colobus P. and S., Proc. A. N. S. Phila., 1897, p. 474, pi. 11, figs. 17-20. 



Type no 2886 A. N. S. P. 



PELECYPODA. 



NUCULIDAE. 



Nucula (AcJla) tuberculata Gabb. Plate XXXVIII, fig. 5. 



Nucula (Acila) tuberculata Gabb, Trans. Ainer. Philos. Soc, xv, 1873 r; 255 



The right valve is a trifle larger and its lunule is smaller, that of 

 the left valve being large. The narrow escutcheon is smooth. Pos- 

 terior dorsal slopes are obliquely corrugated, the rest of the valve 

 tuberculate in the middle and upward, the tubercles obsolete in the 

 lower third, which has sculpture of growth striae and fine, not prom- 

 inent, radial threads. There are 8 anterior teeth, 16 posterior, in 

 a specimen 6.5 mm. long. 



Length 7, alt. 6.2, diam. 4 mm. 



Type and numerous separate valves are no. 2658 A. N. S. P. 



Nucula tenuisculpta GJabb. Plate, XXXVm, fig. 6. 



Xucula tenuisculpta Gabb, Trans. Amer. Philos. Soc, xv, 1873, p 255. 

 ?NuculacrenulataX. Ad.,Dall, '"Blake" Pelecypoda, Bull. M.C. Z. xii, no. 6, 

 p. 247; Trans. Wagn. Inst., iii, p. 577. 



Dall has identified Gabb's species with the recent N. crenulata, 

 which appears to be typically much more coarsely sculptured. As 

 the numerous specimens from Santo Domingo are very uniform in 

 sculpture it seems possible that they form a recognizable race or 

 perhaps a species. 



N. tenuisculpta is finely wrinkled concentrically^ and radially 

 closely striate, the striae appearing as gray lines, which so far as we 

 can tell are little if at all impressed. Internal border finely crenu- 

 lated. The largest of numerous valves measures, length 3.35, alt. 

 2.8 mm. 



Gabb's type is no. 2656 A. N. S. P. 



