C 109 ] 

 3. Polygyra septemvolva, Say. 



Plafe 11, figure 22. 



Shell discoidal, with seven whorls, which are closely ribbed- 

 striate above, the periphery subangular ; smooth below, and ex- 

 hibiting about four whorls besides those forming the walls of the 

 rather large umbilicus. Horn color. 



Diam. 14, height 3-5 mill. ^Coll-'^^ • ^ -^ ■ 



'" Florida.' 



4. Polygyra Carpenteriana, Bland. 



Plate 11, figures 23, 24. 



Subdifecoidal, spire slightly elevated ; whorls 5J to 6J, thin, 

 shining, closely • obliquely ribbed above, smooth beneath the 

 angular periphery ; base showing 2J whorls, with a minute per- 

 foration. Light horn color or -rufous, with frequently opaque 

 irregular bands crossing the whorls. 



Diam. 8— 10, alt. 3— 4 mill. Ccl-' '(:>■--■ ^ 

 East Florida. 



5. Polygyra VOlvOXiS, Parreyss. 



Plate 11, figure 25. 



Spire a little elevated ; whorls 7, flattened above, convex be- 

 neath, the periphery carinate ; upper surface and base near the 

 aperture closely ribbed, the balance of the base smooth; over 

 two whorls visible below, besides a narrow umbilicus. Horn 

 color, with frequently white blotches or bands running across 

 the whorls. 



Diam. 9, alt. 4 mill. C(P^.T.Q..-n. 



East Georgia and Florida. 



This is perhaps a young state of P. septemvolva, Say, 



