"ww."'] PROCEEDINGS OF THE NATIONAL MUSEUM. 261 



gin. The interior in fresh specimens is pink, white, or pinkish choco- 

 late, darker behind; sometimes of a rich salmon color. The species 

 does not agree with any of Conrad's Tertiary species, and is entirely dis- 

 tinct from the C. antillarum Reeve, the only other recent species of the 

 true Crassatellas yet known to inhabit this region. It has not yet been 

 found in the southeastern Antilles. 



Family ASTARTID^F. 



Germs CIRCE Schumacher. 



Subgenus GOULDIA C. B. Adams. 



Gouldia cerina C. B. Adams. 



This species was collected at Station 2758, 90 miles southeast from 

 Cape San Koque, Brazil, in 20 fathoms, shelly bottom. This is by far 

 the most southern habitat for the species yet recorded. 



Suborder LUCINACEA. 



Family UNGULLMD^? 



Genua CRYPTODON Turton. 



Cryptodon barbarensis Dall. 



Plate viil, Fig. 9. 



Shell white, superficially chalky, rather compressed, rounded below, 

 the beaks not very prominent; the surface is sculptured only with in- 

 cremental lines; there is a rather large impressed lunular area not cir- 

 cumscribed by a line ; behind there is an upper, narrow 7 and deep radial 

 depression with a lower, wider and less marked second one, which make 

 corresponding flexuosities of the posterior margin; a narrow rather 

 deep groove runs near the margin outside the ligament marking off a 

 narrow elongated escutcheon; interior white, unpolished; hinge eden- 

 tulous. Maximum longitude of shell 17; altitude 17; diameter 10 ,nm . 



Hab. — U. S. Fish Commission Station 2810, off the Santa Barbara 

 Islands, California, in 270 fathoms, green mud. 



This fine species is nearer C. Sarsii than any other, but has decidedly 

 more elevated and narrower beaks. It is probable that all these shells 

 should be called Axinus, as there can be little doubt that his fossil type 

 really belongs to this group. As long as even that little exists, how- 

 ever, it is a question whether Sowerby's name should be adopted. 



Soft parts.— The foot is extremely slender (0.5 imu ), with a small spin- 

 dle-shaped dilation at the distal end, circularly rugose, and about 10 ,um 

 long, as contracted in alcohol. The gills are as long as the shell, or 

 nearly; the stem has a dorsal and a ventral lamina, and the dorsal 

 lamina is reflected outward and downward, until its lower margin is on 

 a level with the stem. There is only one pallial and branchial opening, 



