139 ^'^^- Maurice and Claiborne Pelecypoda 139 



Univ. Mits., Austin). 



Horizon. — Claiborne and St. Maurice Eocene. 



Specimens figured. — Paleont. IMus. Cornell Univ. 



Localities.— QX^ShorViQ and Lisbon, Ala. Shell Bluff, Ga. 

 These Georgia imprints and casts seem closely related to perovata 

 and neusensis. 



Meretrix mortoni Con., PI- 43. Figs. 14, 15. 



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 Q.oi\., Am. Jr. Conch., vol. i, 1865, p. 6. 

 Cytherea csqnorea van cominduta de Greg., partivi, Mon. Faun. Eoc. 



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

 C. crquorea Cossm., Notes Compl. &c. , 1S93, p. 10, var. jnortoni. 



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. ceqiiorea, nobis, [C. liydii 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. ccquorea 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 cBquorea, 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. Mortoni 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/« 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 Jigured. — Paleont. Mus. Cornell Univ. 



Locality. — Claiborne, Ala. 



