344 DESCRIPTIONS OF CARIBBEAN MIOCENE FOSSILS. 



The generic determination given above is, I believe, correct; although I can- 

 not be perfectly positive. The shell is crystalline and imbedded in tough sand- 

 stone. I succeeded in uncovering a portion of the hinge, and the teeth, so far as 

 I could see, warrant my determination. 



CALLISTA, Poll. 

 C. MACUi/ATA, Linn., sp. 



Venus maculata, Linn., Syst. Nat., p. 1132. 



Cytherea (meretrix) Dariena, Con., Pacific R. R. Report, v. 6, p. 12, PL 5, fig. 21. 



Not id., vol. 5, p. 328, PI. 6, fig. 55. 



Mr. Conrad redescribed this shell from Gatun; and I have since encountered 

 it at Sapote. 



CYCLINA, Dest. 



C. cyclica, Guppy. 



JDosinia id., Guppy, Quart. Journ. Geol. Soc, vol. 22, p. 582, PI. 22, f. 15. 



Cyclinaid., Gabb, Tr. Amer. Philos. Soc, v. 15. 



A single specimen in the Newberry lot from Gatun. 



CLEMENTIA, Gray. 



C. Dariena, Conrad, PL 44, fig. 16, 16a. 



Meretrix Dariena, Con., Pacific Railroad Report, voL 5, p. 328,*PL 6, f. 55. 



Not Cyih. (M.) Dariena, Con., loc. cit., voL 6, p. 12, PL 5, f. 21. 



I found a beautifully preserved specimen at Sapote, and had the satisfaction of 

 convincing Mr. Conrad of the above synonymy. It is figured of natural size. A 

 poor specimen occurs in the Newberry lot in the Academy's museum. 



CARDIUM, Linn. 

 C. (protocardia) Newberryanum, Gabb, n. s., PL 44, fig. lY. 



I propose this name for the internal mould of a Protocardia in the Newberry 

 collection from Gatun. Although only a cast, it is clearly an unnamed species, 

 and its form is so characteristic that it cannot be mistaken. It is nearly equilate- 

 ral, unusually strongly truncated posteriorly, and the base is gently excavated in 

 front of the posterior angle. Being a cast, of course no surface characters are 

 obtainable, and being somewhat compressed, the amount of its convexity is uncer- 

 tain. , 



Figure. Natural size. 

 C. (trachycardium) Dominicense, Gabb, Tr. Amer. PhiL Soc, vol. 15. 



Found by me at Sapote, Costa Rica, and by Dr. Newberry at Gatun. 



