24 VIVIPARA. 



Length 13-5, diam. 10 mill. 



Alexandria, La. 



Smaller than V. Troostiana, of different form 

 and darker color. Mr. Binney considers the 

 two identical, but they ajDpear to me to be 

 quite distinct. I have never seen any speci- 

 mens of either except those in Mr. Lea's 

 cabinet. 



11. VIVIPARA PONDEROSA, Say. 



Hald., p. 13, t. iv. 

 Plate 14, fig. 4. Plate 15, fig. 6. 



This species inhabits from Ohio to Iowa, 

 and southward to Alabama. I have figured 

 (fig. 4) an Alabama specimen as representing 

 the var. A mentioned by Haldeman. V. regu- 

 laris, Lea, is undoubtedly the young of this 

 species ; my figure (fig. 6) is drawn from one 

 of Mr. Lea's types. 



(50) 



