44 Bulletin 31 44 



A. J. Conch, vol. i, p. 12 ; nor is it shown as fig. 16, pi. 47, in 

 Jr. Phila. Acad., vol, 4, 2d ser. as Conrad states. 

 Trigonarca perplana Dall, Trans. Wag., &c., III. 1895, p. 606. 



Conrad's original description. — Shell suboval, much compressed : 

 with radiating striae ; anterior and posterior margins wide and obtusely 

 rounded or subtruncated ; beaks central not prominent ; series of cardinal 

 teeth interrupted by an oblique fosset ; margin entire. I^ength more than 

 half an inch. 



Locality. — Claiborne, Ala. 



Three specimens, presumably the types are in the Conradian 

 collection of the Phila. Academy. 



This resembles in some respects a great over-grown ellipsis 

 but it is quite probably a distinct species. It is very rare, neither 

 de Gregorio nor Cossmann found a single specimen in their re- 

 spective materials from Claiborne Bluff. The latter, however, 

 shows an entirely different form for Limopsis perplanus (figures 

 20-21 , pi. i) which Dall very properly rQ.'a2im.Q.s cossmanni. 



This is the giant Trinacria from the Claiborne sands and ap- 

 proaches in dimensions the declivis from the St. Maurice horizon 

 below. 



Horizon.' — St. Maurice Eocene. 



Specimens figured . — Paleont. Mus. Cornell Univ. 



Trinacria ellipsis Lea, PI. 19. Figs. 12-17. 



Peduculus ellipsis Lea, Cont. to Geol., Dec, 1833, p. 78, pi. 3, fig. 56. 

 Limopsis ellipsis Con., Jr. Phil. Acad. Nat. Sci., IV, i860, pi. 47, fig. 9. 



(Named on p. 297.) 

 Trigonarca ellipsis Dall, Trans. Wag. &c.. Ill, 18^5, p. 606. 



Lea' s original description. — Shell transversely elliptical, compressed, 

 inequilateral, concentrically and minutely striate, with small longitudinal 

 rugose ribs, more strongly marked on the posterior and anterior parts ; 

 beaks rather elevated, recurved ; hinge teeth very small, numerous and 

 scarcely interrupted in the middle ; cicatrices impressed ; cavity of the shell 

 shallow ; margin entire. 



Diam . .2, Length 7-2oths, Breadth 9-2oths of an inch. 



'■''Observation. — In some of its characters 'Ca&ellipsis closely resembles 

 the minor, but is eminently distinguished by the absence of marginal cren- 

 ulations. It is more transverse and has smaller dorsal teeth. Immediately 

 under the beak is a fosset-like impression, which may have been the seat of 

 the ligament. In this it has some resemblance to the nucula ; but is placed 

 above the row of arched teeth. ' ' 



