255 LiGNiTic Stage 63 



Meretrix subimpressa var. Pl. 12, figs. 6, 7. 



Syn. C. subimpressa Con., Jour. Acad. Nat. Sci. Phila., vol. i, p. 130, 

 pl. 14, fig. 26. 

 C. perovata? Aid., Bull, i, Geol. Surv. Ala., p. 53. 



Conrad' s original description. — "Ovate, slightly ventricose, 

 smooth and polished, with concentric slightly inipres.sed lines 

 on the anterior side ; anterior side short, rather acutely round- 

 ed ; posterior side produced, acutely rounded at the extremity; 

 dorsal margin long, oblique, slightly curved ; beaks prominent; 

 lunule lanceolate, defined by a slightly depressed line. Length, 

 lyi in. Height, .8 in. Locality: Marlbourne, Hanover coun- 

 ty, Virginia. Mr. Ruffin. 



' ' This species may be distinguished from C. csquojra bj^ its 

 greater comparative length, smaller size and wanting the strong 

 furrows of that species. Mr. Ruffin obtained several entire 

 specimens. ' ' 



The variety here referred to has some resemblance to M. 

 pearlensis Har. , but has no indications of such markings. From 

 subi77ipressa typical it differs in having its upper and basal mar- 

 gins more rectilnear, its posterior very prolonged, but finally 

 abruptly truncated, its anterior more produced and circular, its 

 beaks slightly more prominent. The moderately deep truncated 

 pallial sinus is the same in both. 



Many specimens are scarcely distinguishable from young M. 

 IcBvigata Lam., though the beaks are always a little pronounced 

 and there are no signs of radiating lines. 



Locality. — Alabama: Woods Bluff. 



Specimens figured. — Paleontological Museum, Cornell Uni- 

 versity. 



Meretrix hatchetigbeensis. PL 12, figs. 11, 12. 



Syn. Cytherea hatchetigbeensis Aid. , Bull, i, Geol. Surv. Ala., 1886, p. 

 39. pl- 4, fig- I. 



AldricK' s original description. — "Shell rather thick, inflated, 

 sub-rotund, transversely striate — the different periods of growth 

 marked by a dropping down of the concentric lamina, giving 

 a ridge-like appearance ; umbones swollen ; beaks elevated ; 

 lateral tooth in left valve transverse, conical and strong ; liga- 

 ment short-curved ; excavation of the pallial impression angu- 

 lar ; margin of the shell entire, thickened in some specimens. 



