14 VIVIPARA. 



r a , Linn. (= Uiieafa, Kiister) , Georgiana, 

 Lea, Ben gale n sis, Hald. (= Waltoni, nob.) 

 carinata, Val., inornata, Biuney. 



Melantho, subpurpurea, Say, p o n- 

 d e r o s a , Say, d e c i s a , Say, genicula, 

 Conrad, i n t e g r a , Say, Texana, Tryon, 

 De Campi, Currier, Nolani, Tryon, subsolida, 

 Anth., coarctata, Lea, ohesa, Lewis, rnfa, Hald., 

 Mllesii, Lea, gihha, Currier, lima, Anthony, 

 exilis, Anth., incrassata, Lea, Troostia7ia, Lea, 

 Haleiana, Lea. 



TuLOTOMA, bimonilifera. Lea. 



It is a curious fact that the family Vivipa- 

 ridse is not represented west of the Rocky 

 Mountains by a single species (nor is it found 

 at all in South America), although the Rissoi- 

 dse, Valvatidaa and Limnaeidae are all repre- 

 sented there. 



[40] 



