139 S'^- Maurice and Claiborne Pelecypoda 139 



Univ. Mus., Austin). 



Horizon. — Claiborne and St. Maurice Eocene. 



Speciviens figtired. — Paleont. Mus. Cornell Univ. 



Localities. — Claiborne and Uisbon, Ala. Shell Bluff, Ga. 

 These Georgia imprints and casts seem closely related to perovata 

 and neusensis. 



Meretrix mortoni Con., PI- 43. Figs. ^4^15, f<o. 



Cytherea mortoni Con., Jr. Phila. Ac. Nat. Sci., vol. 7, 1834, p. 150 ; 



pi. 20, fig. I. Harris' Reprint Con. Foss. Sh., &c. 

 Dione mortoni Con., Am. Jr. Conch., vol. i, 1865, p. 6. 

 Cytherea ceqiiorea var. coniinduta de Greg. , partim, Mon. Faun, Hoc. 



Ala., 1890, p. 217, pi. 34, fig. 5. 

 C. cequorea Cossm., Notes Compl. &c., 1893, p. 10, var. mortoni. 



Conrad's original description. — Shell ovate, convex, with numer- 

 ous regular impressed lines ; lunule cordate, defined by an impressed line. 

 Length two inches, height one and a half inches. 



Locality. — Claiborne, Ala. 



Allied to C. cequorea, nobis, [C. hydii Lea) but is a much larger spe- 

 cies, with more regular sulci. It is not uncommon at Claiborne, and I 

 could readily distinguish it from C. ceqttorea in every stage of growth. I 

 give it the name of my friend. Dr. S. G. Morton, through whose kind as- 

 sistance I was enabled to visit the most remarkable tertiary deposits in the 

 southern states. 



There is, to be sure, a somewhat superficial resemblance to 

 be noticed between this form and cequorea, but it appears to us 

 that there is no close real relationship between the two ; in fact 

 they would seem to belong to two quite distinct stocks of the 

 genus. Morto7ii is much larger, more elliptical in outline, less 

 cuneiform, thinner, and with a more arching ligamental margin 

 and much more perfect, or even, surface undulations. It is a 

 flattened-out/^;^z^a/a with the lines, shown peripherally in that 

 species, drawn over the whole surface. 



Type. — Phila Acad. (^Mortoni card contains also perovata 

 and P. var. aldrichi.) 



Horizon. — Claiborne Eocene. 



Specimens figured. — Paleont. Mus. Cornell Univ. 



Locality. — Claiborne, Ala. 



