354 DESCRIPTIONS OF NEW SPECIES OF FOSSILS 



OLIVA, Brug. 



O. RECTicuLARis, Lam., A. S. V., v. 10, p. 613. 

 0. cylindrical Sby., Q. J. Gr. S., v. 6, p. 45. ■ 



Most of the specimens retain their polished surface and color patterns perfectly 

 preserved, and the present series removes all doubt that I previously had as to the 

 specific identity of the Santo Domingo fossil with the living forms. 



0. ISPIDTJLA, Linn., Syst, Nat., 12 ed., p. 1188. 



These olives also retain enough of their color to render certain the determina- 

 tion, based principally on size and figure, notwithstanding the fact that the recent 

 shells are only found in the Eastern seas. 



FASCIOLARIA,Lam, 



F. TULiPA, Linn, sp., Syst. Nat., Ed. 9, p. T54. 



F. distans, Lam., A. S. V., vol. 9, p. 433. 



F. semi-striata, Sby., Q. J, G. S., v. 6, p. 49. 



F. rhomboidea, Rogers, Tr. Amer. Philos. Soc, v. 6, p. 376, PL 30, f. 3. 



A widely spread shell, occurring in the miocene of the West Indies and the 

 United States, and yet living on the same coasts. F. tulipa and F. distans diff"er 

 only in those characters in which shells are most likely to vary, while in this 

 respect F. rhomboidea is intermediate, and on comparing the Costa Rican shells, it 

 is impossible to ally it more with one than another of these forms. In short, the 

 species is the same throughout, as even some of the students of living mollusca are 

 inclined to admit, and as is proven by the older forms. The divergence in the 

 character of the markings seem to have begun in the miocene. In rhomboidea 

 the lines are 2.5 mill, apart^ in distans twice as far, and .in tulipa close together. 



LATIRUS, Montf. 

 L. iNFrNDiBUiiUM, Gmel. in Lam-, A. S. V., v. 9, p. 386, 



Fossil in the Miocene, West Indies, and still living on the same coasts. 



VASUM, Bolt. 



Y. MURicATUM, Born. sp. Desh , A. S. V., v. 9, p. 391. 



Turb. Hailensis, Sby., Q. J. G. S., v. 6, p. 5a. 



F. Haitensis, Gabb, Tr. Amer. Phil. Soc, 1873, p. 218. 



In the above quoted memoir I followed Sowerby in separating the fossils from 

 the living form. But from the more recent fossils now before me, I find the 

 suture character, on which I depended, exists in a transitional degree, and the West 

 Indian fossil must be recognized as the lineal ancestor of the recent shell yet com- 

 mon in the West Indies. 



