44 Bulletin 31 44 



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

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

 Trigonarca perpla7ia 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. Length more than 

 half an inch. 



Locality. — Claiborne, Ala. 



Three specimens, presumably the tj^pes 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 perplayius (figures 

 20-21 , pi. i) which Dall very properly renames cossmafzni. 



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 figicred . — Paleont. Mus. Cornell Univ. 



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



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

 Liptopsis 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 \he ellipsis closely resembles 

 the minor., but is eminently distinguished by the absence of tnarginal 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." 



