[ 82 ] 

 3. Vitrina Pfeififerii, Newcomb. 



Plate 3, figure 3. 



Globoselj depressed, whorls 3 ; suture very finely margined ; 

 aperture large, oblique, roundly ovate; lip thin, columella 

 arched, 



Diam. 5, height 2 mill. 



Carson Valley, Cal. 



V. limpida is smaller, with only 2| whorls, and thinner. Y. 

 Angelicx is more globose, with more prominent spire. 



BINNEYA, Cooper. 

 1. Binneya notabilis, Cooper. 



Plate 3, fig. 4. 



Depressed, smooth and shining, epidermis extending be- 

 yond margin of aperture, translucent when young, but opaque- 

 ly thickened when old. Nuclear whorl with about thirty 

 delicate transverse ribs. Pale brown. 



Diam. 12, height 3 mill. 



Santa Barbara I., Cal. 



HELICELLIN^. 



Genera. 



Maceocyclis, Beck. Shell moderate, widely umbilicate, 

 planorboid, striate; whorls 4-5, the last wide, descend- 

 in o- and flattened above at the aperture. 



Hyalina, Ferussac. Shell moderate or small, globosely 

 depressed, moderately umbilicated or perforated, or 

 umbilicus closed, but impressed; whorls 4-6, vitreous, 

 shining, regularly increasing, not angled at the pe- 

 riphery, nor flatly depressed at the aperture. 



MACROCYCLIS, Beck. 

 1. Macrocyclis Newberryana, W. C Binney. 



Plate 3, figure 5. 



Large, whorls 6, first ones flattened, but ultimate one con- 

 vex, beneath convex; reddish-brown, striate, decussated by 



