38 Bulletin 31 38 



IJnwpsis cuneus Con., Jr. Acad. Nat. .Sci., vol. 4, i860, p. 297, pi. 47, 



fig. 17. 

 Trigonouelix ciineiis Con., Amer. Jr. Conch, vol. i, '65, p. 12. 

 Linwpsis ( Trigonoccelia) cuneus de Greg., Mon. Faun. Eoc. &c., 1890, 



p . 191, pi. 23, fig. 28 b. 

 Trinacria cuneus Cossniann, Notes Suppl., 1893, p. 15. 



Conrad^s original description. — Shell cuneiform, broad, posterior end 

 flattened and forming an angle at the umbonial slope. Length, half an 

 inch. This is a very remarkable species very unlike any I have hitherto 

 seen. 



Locality. — Claiborne, .W?l., London clay. 



This is the most cuneate of the American Eocene species of 

 this genus and is closely allied to certain Paris Basin forms. A 

 clo.se study of the beaks and ligamental pits in this and the for- 

 eign representatives is sufficient to prove that we have here sim- 

 ph' one extreme in a long series of species, all really closely akin. 

 The shortness of the series of hinge teeth is brought about by 

 the pointed umbones ; the beaks are really opisthogyrate ; the 

 pit is anterior to the beak as developed and is necessarily deep to 

 possess the required volume in such a contracted space ; radii no- 

 ticeable anteriorly and posteriorl3\ 



The sperimens figured are from the Claiborne sand. 



In Bull. I of the Ala. State Geol. Surv. Aldrich has starred 

 this in the Lisbon column (and not the Claiborne) but all speci- 

 mens known to me are from the 17 ft. "sand" bed. 



7)'/>^.— Phila. Acad. Coll. 



Specime7is figured. — Paleont. Mus. Cornell Univ. 



Trinacria ledoides Meyer, PI. 18. Figs. 10 a. 



Trigonoccelia ledoides Meyer, Bull. Ala. Geol. Surv., No. i, 1886, p. 



79, pi, I, fig. 20. 

 Liinopsis ( Trigonocuelia) ledoides de Greg., [Mon. Faun. Eoc, Ala., 



1890, p. 191. 

 Trinacria ledoides Dall, Trans. Wag. &c, vol. Ill, p. 604. 

 Trinacria ledoides Cossmann, Ann. de Geol. and Pal., 12th liv., 1893, 



p. 15- 

 Meyer's original description. — Convex, ovate; posterior side carin- 

 ated ; hinge narrow, divided by a minute pit ; about eight teeth on each 

 side ; more vertical near the pit, more horizontal near the end ; surface with 

 concentric lines of growth crossed by indistinct radiating lines, which are 

 not perceptible on the umbo, beak turned toward the carinated side ; the 



