[137] 



on the outer lip ; umbilicus open, rather large. Chestnut 

 color. 



Length -90, diam. "65 mill. 



Inhabits nearly the whole country east of Mississippi River. 



6. Vertigo ovata, Say. 



Plate 15, figure 22. 



Ovate conical, ventricose, apex conical, whorls five, very con- 

 vex, with deep suture ; aperture half round, truncate above, lip 

 thickened within and reflected, marked externally by a groove, 

 outer lip incurved in the middle ; teeth six to eight, a large 

 sharp one and a small one on the parietal wall, two on the 

 columellar margin, one of them at its base, and two on the 

 labrum, one of which is also basal ; umbilicus open. Dark 

 amber colored, shining. 



Length 1-8, diam. 1 mill. 



Northern United States. 



6. Vertigo simplex, Gould. 



Plate 15, figure 23. 



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

 suture ; aperture rounded, peristome nearly continuous, scarcely 

 reflected, without teeth ; umbilicus nearly covered by the lip. 

 Dark brown. 



Length 1-6, diam. '8 mill 



Maine to Pennsylvania. 



7. Vertigo ventricosa, Morse. 



Plate 15, figure 26. 



Ovate-conic, smooth and shining, apex obtuse; whorls four, 

 very convex, with deep suture ; aperture small, rounded triangu- 

 lar, the middle of the outer lip incurved, lip widely reflected 

 and thickened within ; there is one large tooth on the parietal 

 wall, another occupies the columellar lip, with a smaller one 

 near its base, and there are two large teeth on the outer lip, 

 making five in all ; umbilicus smooth. Light chestnut color. 



Length 1-6, diam. 1 mill. 



Maine, New Hampshire, Mohawk and Greenwich, New York. 



