TZ Bulletin 3 (94) 



LA BIOS A. 



Labiosa canaliatlata . 



Syn. Liitraria canaliculata S2iY, Jr. Ac. Nat. Sci. Phila., 

 vol. 2, T822, p. 3T r. 

 Labiosa canalicidata Har. , 4tli Ann. &c. , p. 121. 



Range in depth. — From 46 to 2,871 feet. 



CORBULA. 



Coi'bula galvestonensis , n. sp. PI. 2, fig''s 4, a. 



Specific characterization. — This little round Corbula belongs to 

 the same section as dispaidlis d'Orb. and krebsmna C. B. Ad., but 

 differs from the latter in being less produced posteriorly, and from 

 the former in the lack of an umbonal carination. The last men- 

 tioned feature gives disparilis a biangulate posterior margin while 

 the corresponding margin of this species is strongly arcuate. 



Range in depth. — From 2,443 to 2,650 feet. 

 Corbula {Potamomya) priscopsis, n. sp. PI. 2. fig's 5, a. 



Specific characterization . — General form as indicated by the fig- 

 ures ; apex acute ; a ridge traversing the umbonal slope radially ; 

 a monoclinal ridge (sloping posteriorly) extending from beak to 

 anterio-basal margin ; hinge teeth characteristic of this sub-genus. 



Unfortunately but one specimen of this peculiar form was ob- 

 tained. It resembles /m<f« Mart, from southern Brazil. 



Range iyi depth. — From 2,443 to 2,448 feet. 



Corbula swiftianaf PI. 2, fig. 6. 



Syn. C swiftiana Ad., Cont. to Conch., 1852, p. 236. 

 Corbiila, sp. undt., Har., 4th Ann. &c. , p. 121 



There are several recent so-called species inhabiting the south- 

 east coast of the United States and the West Indian shores, and 

 others the western coast of South and Central America that can 

 scarcely be distinguished from this species when large numbers of 

 .specimens are brought together. Szmftiana of the West Indies" is 

 unhesitatingly referred by Arango (Faun. Mai. Cub., 1878, p. 

 253) to nasuta Sby. from the west coast of U. S. Columbia. Dall 

 however in Bull. 37, U. S. Nat. Mus., 1889, p. 70 restores szvift- 

 iana to specific rank, also admits the presence of nasuta on our 

 eastern coast. The Texan forms resemble most nearly immature 

 specimens of swiftiana as understood by Dall in the work just cit- 

 ed, pi. 2 fig. 5a, though some specimens have an outline closely ap- 



