43S 



PROCEEDINGS OF THE ACADEMY OF 



[May, 



A NEW ECPHORA OF THE CHESAPEAKE MIOCENE. 



BY HENRY A. PILSBRY. 



Ecphora parvicostata n. sp. Fig. 1. 



The shell is shaped like the more globose forms of Ecphora quadri- 

 costata (Say); the umbilicus moderate, rapidly contracting inward, 

 not so ample as in E. q. umbilicata (Wagner). The last whorl has 

 four very low, narrow spiral ribs; the surface above the upper rib 

 slopes upward to the suture, immediately below which it is a little 

 swollen. The spiral ribs are stronger on the spire, where two are 



/ 



&, 





Fig. 1. — Ecphora parvicostata, natural size. 



exposed, the suture revolving on the third. Between the ribs there 

 are irregular growth-wrinkles, but no spiral striae. 



Length 82, diam. 70 mm. (apical whorls wanting). 



Three specimens of this form were found in a tray together with 

 Ecj>Jmr<t quadricostata umbilicata (Wagner) and E. tricostata .Martin, 



