P L E I C E N E P S S I L S . 67 



CAEDITA TRIDENTATA. — Say. 



Plate XIX. Pigs. 8-msb 9. -Tib 



Cardita tridentata, Say, Jour. Ac. Nat, Sci., Vol. 5, p. 216. 

 Cardita tridentata, Con., Foss. Ter. For., p. 76, pi. 43, fig. 11. 



C. testa rotundata trigona, crassa; radiatim costata; costis ekvatis, crenulatis. 



Description. Shell round, triangular, thick, radiately ribbed ; ribs elevated, strongly 

 crenulated. 



This little species is distinguished by its sub-triangular outline, thick, robust and 

 coarsely crenulated ribs. The beaks are slightly turned forward. There are two teeth 

 in the left, and one in the right valve. 



The species is an inhabitant of the southern coast, and we have never found larger 

 specimens. 



Plate XIX. Fig. $>, Interior of right valve. 



" p, Exterior of left valve, natural size. 



Locality. Sumter District. Museum, College of Charleston. 



C A R DITA C A R I N A T A . 

 Plate XIX. Fig."Ht- in 



Carditamera carinata, Con., Proc. Ac. Nat. Sci., Vol. 1, p. 305. 

 Carditamera carinata, Con., Foss. Ter. For., p. 65, pi. 37, fig. 1. 



C. testa elongato-ovata; latere buccali brevissimo; costis transversis radiantibus, ancjulatis, 

 muricato-squamosis . 



Description. Shell ovately oblong, buccal side very short; ribs radiating transversely, 

 angular muricated and squainose. 



18 



