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ART. II. — Descriptions of one netv Cretaceous, and seven New Eocene Fossils. By 



T. A. Conrad. 



The Eocene fossils described in this paper were obtained in Georgia by 

 J. Hamilton Couper, Esq. The name of each species of Echinode7'mata has been 

 adopted at the particular request of Mr. Couper. 



TESTACEA. 

 MITRA. 



M. GEORGiANA. PI. 1, fig. 4. — Fusiform ; spire turreted ; volutions five or six, tuberculated, tubercles acute 

 and extending over the inferior half of each volution ; upper portion contracted and angulated ; suture 

 impressed ; aperture elliptical, about half as long as the shell; columella with four plaits. 



This shell has been inadvertently figured among the Newer Eocene species. It is 

 known to occur only in the lower division of the Eocene strata. 



CATOPYGUS, Agas. 



C. CoNRADi. PI. 1. fig. 9. — Ovate, longitudinally subangulated in the middle, caused by the slightly 

 flattened surface of the disk; sides of posterior margins obliquely truncated ; ambulacral pores minute ; 

 anus transversely oval; extremity truncated ; base slightly concave about the mouth except posteriorly, 

 where it is slightly convex. 

 C. Conradi, Couper. MSS. 



Locality. Palmyra, Lee county. In white limestone. 



C. oviFORMis. PI. 1, fig. 15. — Ovate, rounded above; posterior lateral margins obliquely truncated ; anus 

 oval, not transverse, posterior end below the anus emarginate. 



Locality. Timber Creek, N. J. Cretaceous limestone. 



A smaller species than the preceding, and differs in being emarginate posteriorly ; 

 in the anus not being transverse ; in the more rounded disk, &c. 



This limestone in New Jersey is linked with the green sand by the presence of 

 Ostrea vesicularis, Gryplicea vomer., &c. The same rock at Wilmington, N. C, shows 

 still more intimate connection with the lower green strata, by the presence of 

 Ammonites placenta, De Kay ; Trigonia thoracica, Morton ; and CitTUS crotaloides, 

 which were discovered by Mr, Tuomey. Lyell and Tuomey regard the limestone 

 at Wilmington as a member of the Eocene formation, but the occurrence in it of the 

 three fossils above mentioned, together with the corallines of the Timl^er Creek beds, 

 are sufficient evidence of its Cretaceous character. 



