144 PHYSA. 



21. PHYSA D'ORBIGNYANA, Lea. 



Plate 7, fig. 8. 



Shell broadly oval, obliquely inflated, widely 

 striate, semi-transparent, very fragile, dove- 

 color ; spire rather obtuse ; whorls five, the 

 last very large; aperture very large, broadly 

 elliptical ; outer lip regularly expanded, thick- 

 ened and pale saffron color under the margin ; 

 columella impressed and slightly thickened in 

 the middle, and furnislied with a fold. 



Length 14, diam. 8 mill. 



Salt Lagoon, near Monterey, California. 



This species is interesting from the fact of 

 its inhabiting water which is quite salt. It is 

 very near in outline to lieterostropha, Say, but 

 it is a rather smaller, thinner species, not quite 

 so long in proportion, and the longitudinal 

 stria3 distinguish it at once. These stride are 

 rather coarse and distant, and the whole sur- 

 face of the whorls is covered over with minute 

 parallel stria). The aperture is about three- 

 fourths the length of the shell. 

 (60) 



