143 St. Maurice and Claiborne Pelecypoda 143 



Mosley's Ferr)^ Brazos Co. ; Cedar Cr., Robert.son Co. ; Alum 

 Bluff, Trinity River ; Hurricane Bayou, Houston Co. ; Collier's 

 Ferr}', Brazos River, Burleson Co. 



Louisiana : Three miles S. E. of Negreet ; Simpkins' Place; 

 Clear Lake ; Marble Quarr3^ 



Mississippi : Wautubbee. 



Alabama : Hamilton Bluff, Lisbon, base of Claiborne. 



South Carolina : Center Hill. 



North Carolina : Rocky Landing, Neuse River. Var. nut- 

 tali^ 16-17 utiles above Newbern, Neuse River, Exp'd. '98. 



Meretrix nutlali Conrad, PI. 45, Figs. 4, (5-8vars. ) 



Cytherea Nuttali Con. Jr. Phila. Acad. Nat. Sci.,-vol. 6, 1834 p. 149. 

 Dione nuttali Con., Amer. Jour. Conch., vol. i, 1865, p. 6. 



Conrad's original description. — Shell subcordate, ventricose, with 

 crowded, elevated acute concentric lines on the inferior portion, obsolete 

 above ; beaks prominent ; lunule cordate, merely defined by an obscure im- 

 pressed line ; cavity of the umbo capacious. 



Locality. — Claiborne, Alabama. 



This species resembles C. PoulsoJii, nobis, {C.globosa Lea) but differs 

 in its striae and in the beaks which are not so greatly curved forwards. It 

 is smaller than the Poulsoni. 



PI. 19, fig. I of Harris' Reprint of Conrad's Fossil Shells 

 was doubtless taken from the type specimen of nuttali novj in the 

 Phila. Acad, collection, though that is a right valve while Conrad's 

 illustration represents both, especially the left. The specimen as 

 illustrated is somewhat emarginate or truncate antero-basallj", 

 while our specimens are more regularly ovate, with more pointed 

 pasterior. The lunule is exceedingly indistinctly marked off 

 from the main surface of the valve in this species. Several of 

 our specimens are much larger (50-65 mm.) than Conrad's type, 

 (43 mm.) in fact his specimen was dwarfish and somewhat pe- 

 culiar. The sharply incised concentric lines, especially basally 

 are very noticeable in this species. 



Type.—Vh\\2i. Acad. 



Horizon. — Claiborne and St. Maurice (var. forms). 



Specimens figured. — Claiborne ; in C. U. Museum. 



