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) 
