DALL: MOLLUSCA AND BRACHIOPODA. 341 
Cocculina nassa Datt, n. sp. 
Plate 16, figures 3, 6. 
Shell small, white, with a pale brownish periostracum, subquadrate, with the 
apex subcentral, the anterior slope slightly convexly arched, the posterior slope 
direct; apex eroded in all the specimens; sculpture of low, sharp, somewhat 
irregular concentric laminae, which have their height slightly increased by an 
added film of periostracum, and are stronger on the upper part of the cone; 
beside these there are fine lines of growth; the concentric sculpture is crossed by 
subequal fine radial threads extending from the apex to the margin, with few or no 
intercalaries; the radial threads are not laminar like the concentric sculpture, and 
near the apex are closer together, but diverge as they approach the margin, which 
is only crenulate by them in the adolescent stages; the intersections are not 
nodulous; interior polished, bluish white, the muscular impressions hardly visible. 
Length, 8.5; apex, 4.5 behind the anterior margin; breadth, 5.5 ; height, about 
5.0 mm. 
U.S. 8. “Albatross,” station 3392, Gulf of Panama, in 1270 fathoms, hard 
bottom, temperature 36°.4 F. U.S. N. Mus. 123,053. 
This species has the sharpest sculpture of any yet described. It is more ele- 
vated and relatively less arcuate than the preceding species, while none of the 
Atlantic species is so sharply reticulated. 
Cocculina diomedae Da tt, n. sp. 
Plate 16, figures 4, 7. 
Shell rather large for the genus, white with a pale straw-colored periostracum, 
depressed conic, somewhat parallel sided, with rounded ends, apex nearly central, 
eroded; margin thin, sharp, entire; interior bluish-white, polished, the muscular 
impressions strong. Lon. of shell, about 13.0; height, 4.5; length of posterior 
slope, 6.0; width of shell, 8.5 mm. 
U.S. 8. ‘‘ Albatross,” station 3393, Gulf of Panama, in 1020 fathoms, mud, 
bottom temperature 36°.8 F. U.S. N. Mus. 123,052. 
This species in form and size closely resembles C. rathbuni of the Atlantic, but 
on examination with a good lens the fine radial striation of the latter (which is not 
represented on the figures of the species, being too fine for the enlargement) is 
entirely absent, the periostracum is less continuous and not shining, and of a 
greenish tint, while that of C. rathbuni inclines to brown. 
Turbinidae. 
TURBO Liynez. 
Turbo saxosus Woop. 
A dead and broken specimen probably of this species was dredged near Cocos 
Island, at station 3368, in 66 fathoms, rocky bottom. U.S. N. Mus. 123,054. 
