176 Bulletin 29 340 



length 21, altitude 24, diameter 24 mm. Area filicata Guppy 

 from the Manzanilla beds, Trinidad, appears to be similar to this 

 species. 



Localities. — (Exp'd '16) Bluff 2 (comparatively scarce), 

 Bluff 3 (exceedingly abundant and all ages) Cercado de Mao. 



Seapharca hispaniolana , n. sp. 

 Plate 30, Figures 9, 10 



In our Gabb collection there is a complete specimen, and 

 two left valves, of a form somewhat resembling A. cor-aipidonis, 

 Like that, this species is inequivalve, small, solid and high, and 

 the beaks, cardinal area and hinge are similar. The left valve is 

 also handsomely nodulose, but the ribs, numbering twenty-five, 

 are wider than the interspaces and the anterior ribs are not so 

 widely spaced as those of cor-cupidonis; the ribs on the center of 

 the right valve are about as wide as the interspaces and are 

 somewhat less nodulose but not smooth and the discrepancy in 

 sculpture of the two valves is not marked; the umbonal ridge is 

 angular and there is a broad sulcation anterior and parallel to it. 

 Length 22, altitude 22, diameter 22 mm. 



This species can be distinguished from A. cor-cupidonis by 

 its lack of discrepant sculpture, and by the umbonal ridge, angu- 

 lar instead of evenly rounded. We collected hundreds of the 

 former species but not one of this sort which Gabb must have 

 obtained from a locality we did not visit. This species closely 

 resembles in appearance A. (Cunearca) Chemnitzi, which we col- 

 lected on the Monte Cristi beach, but the cardinal area of the 

 fossil is that of a true Seapharca. Our shell also has some re- 

 semblance to A. chemnitzoides Maury from the Oligocene of Trin- 

 idad butlthat, like Chemnitzi is a Cunearca. 



Seapharca rioeanensis, n. sp. 



Plate 30, Figures 3, 4 



Shell small, subquadrate, rather thin, roundly inflated; ribs 

 twenty-eight, style of ribbing almost precisely as in A. cor-cupid- 



