OF THE UNITED STATES. 159 



time since into East Florida, at the Cotvfort, on St. 

 John's river. It is in the collection of the Academy. 



14. H. *concava Shell much depressed; sub- 

 orbicular, horn colour, or whitish, immaculate; vo- 

 lutions five, irregularly wrinkled across, more con- 

 vex beneath; suture distinctly impressed; umbilicus 

 very large, exhibiting all the volutions to the sum- 

 mit distinctly; aperture large, short; labrum to- 

 wards the base very slightly and inconspicuously 

 reflected. 



Inhabits Illinois and Missouri. 



Greatest width 7-10 of an inch. 



Found in moist places near the Mississippi river, 

 on the Missouri as high as council bluff, and on the sea 

 islands of Georgia. It is a much depressed shell. 



15. H. *dealbata. Shell conical, oblong, thin 

 and fragile, somewhat ventricose; volutions 6-7, 

 wrinkled across, wrinkles more profound and acute 

 on the spire; spire elongated, longer than the aper- 

 ture, subacute ; aperture longer than wide, labrum 

 not reflected; umbilicus small, profound. 



Length more than 3-4 of an inch. 

 Breadth 9-20 of an inch. 



In the Cabinet of the Academy and Philadelphia 

 Museum. 



luhabits Missouri and Alabama. 



Cabinet of the Academy. 



In outline it resembles a Bulimus. Four speci- 



