PHYSA. 165 



43. PHYSA SMITHSONIANA, Lea. 



Plate 7, fig. 9. 



Shell elliptical, rather thin, translucent, 

 shining, pale-brown, almost olivaceous ; spire 

 rather acute ; sutures impressed ; whorls five, 

 somewhat convex, the last one large and 

 somewhat constricted ; aperture elongately 

 elliptical ; outer lip somewhat thickened and 

 dark brown under the margin ; columella 

 impressed and twisted. — Lea. 



Length 12, diam. 6 mill. 



Loup Fork of Platte River. 



44. PHYSA DEFORMIS, Currier. 

 Plate 9, fig. 16. 



Shell small, narrowly ovate, thick; whorls 

 four, well rounded, the last not proportion- 

 ately enlarged but somewhat flattened, which, 

 in connection with its well-rounded whorls, 

 (81) 



