18 PALUDINA VIVIPARA. 



without: spire lengthened, apex scarcely round- 

 ed, suture deeply impressed; aperture sub- 

 rotund. 



CoLOii of the outside greenish, or brown; of 

 the inside, whitish. 



Geographical Distribution. Say's speci- 

 mens were obtained from the St. John's river 

 in Florida; Mrs. Say has sent me specimens 

 from the Wabash, and Mr. Conrad from near 

 Tuscambia, Alabama; Mr. Anthony has been 

 informed of its existence near St. Louis, Mis- 

 souri, and in Michigan: Valenciennes' speci- 

 mens are from Lake Erie: Cuba is given as 

 the locality of a specimen in the cabinet of the 

 Academy of Natural Sciences. 



OBSERVATIONS. 



This is one of the very few species common 

 to Europe and North America. A comparison 

 of the soft parts may be necessary to prove 

 those found on different sides of the Atlantic to 

 be identical; but where there is not a sufficient 

 difference in the shells to establish varieties, it 

 is not probable that the soft parts would pre- 

 sent distinctive specific characters. 



Deshayes does not cite Say's figures among 



