OF CONCHOLOGY. 309 



Maine, New HampsWre, Massachusetts, New York, Norfolk, 

 Va. 



Smaller than V. Crouldi, which it much resembles ; it diflfers 

 in the outer lip not being smooth in the middle. 



2. Vertigo corpulenta, Morse. 



Plate 15, figure 24. 



Ovate, striate, polished, translucent, apex obtuse ; whorls 

 four, very convex, with deep suture ; aperture rounded, trun- 

 cated by the parietal wall, lip slightly thickened and reflected ; 

 teeth four, small and obtuse, one on parietal wall, one on the 

 columellar margin, one on the middle of the labrum and one 

 near its base. 



Length 2-5, diam. 1-3 mill. 



Little Valley, Washoe Co., Nevada, Eastern slope of Sierra 

 Nevada, alt. 6500 ft. 



3. Vertigo Gouldi, Binney. 



Plate 15, figure 20. 



Ovate-cylindrical, apex obtuse ; whorls four, convex, with 

 well marked sutures ; aperture semi-oval, truncated above by the 

 parietal wall, the outer lip sub-reflexed, and incurved in the 

 middle ; there are two sharp teeth on the umbilical lip, two more 

 within the outer lip and one on the parietal wall ; umbilicus per- 

 forate. Chestnut color. 



Length 2, diam. 1 mill. 



New England and Middle States. 



4. Vertigo milium, Gould. 



Plate 15, figure 21. 



Ovate with obtuse apex ; whorls five, well rounded, with deep 

 sutures ; aperture semi-oval, truncated above, outer lip incurved 

 in the middle, lip white and reflected, parietal wall covered with 

 callus ; there are two sharp teeth on the parietal wall, a broad 

 tooth on the umbilical margin, with occasionally one or two little 

 tubercles near its base, one in the base of the aperture and two 



