"^"^'"^•1 TERTIARY.— POST-TERTIARY. 315 



Ostrea vespertina Conrad. 



(Plate LXXI, Figs. Si, 3, 4.) 



This form was published in the Journal of the Pliiladelphia Academy 

 of Natural Sciences, II (n. s.), page 300; United States and Mexican 

 Boundary Survey, I, page IGO; and the Pacific Eailroad Eeports, V, 

 page 325. 



It is closely related to both 0. suhfalcata and 0. acalpturata, and is 

 possibly only a variety of one or the other of these species. It was 

 originally described as Miocene, but the locality where it was obtained 

 by Conrad, Carrizo Creek, Colorado Desert, is considered Pliocene by 

 Gabb. 



POST-PLIOCENE. 



Ostrea coiichaphila Carpenter. 



This uame is given as that of a California shell in the Catalogue of 

 Mazatlan Shells in the British Museum (1857), page 161; but not 

 figured. 



There are nine specimens of an oyster in the collection of the Phila- 

 delphia Academy, marked " 0. conchaphila, Cpr.," from the post-Plio- 

 cene of San Diego and False Bay; but whose determination the same 

 may be I am unable to state. The 0. conchaphila, as far as I know, is 

 not stated to be fossil by any paleontologist. Some of the above speci- 

 mens are undistinguishable from recent specimens marked 0. lurida 

 Cpr., also in the Academy collection, which is stated to be fossil by 

 Newberry and Gabb. It therefore appears to me that the specimens 

 marked 0. conchaphila are more likely to be 0. lurida, although their 

 characters do not exactly agree with Carpenter's description of the 

 latter species. 



Ostrea fundata (Say?) F. S. Holmes. 



Post-Pliocene Fossils of South Carolina, p. 11. I liave seen no speci- 

 mens of this species. 



Ostrea gallus Valenciennes. 



Figured without description. Voyage de la Venus ; Atlas de Zoologie, 

 Plate 21. California. A recent species. 



Syn.— O. cerromnns Gabb; Paleontology of California, II, page 35. Cerroa 

 Islands. 



As stated by Gabb, Paleontology of California, II, page 106, 0. cer- 

 rosensis is in all probability itlontical with 0. gallus, which, as figured, 

 is about twice the size of the California fossil. A fossil from the late 

 Tertiary of Peru, received from Professor Raimondi, which is consid- 

 ered by Gabb as the equivalent of his 0. cerrosemis, is about the size 

 of the living species, and undistinguishable from it. 



