SYNOPTICAL TABLE. 



Genus. Bitliynia. 

 Bithynia nuclea, Lea. (Pal.) 

 Bithynia seminalis, Hin^s. (Pal.) 



Amnicola seminalis, Cooper. 

 Bithynia castanea, Mull. 

 Bithynia teutaculata, Lin. (Helix. ) 



Family. VALVATID^. 



Genus. Valvata. 

 Valvata tricarinata, »S'«?/. (Cycl.) 

 Valvata carinata, Sowb. 



unicarinata, De Kay. 

 bicarinata, Lea. 

 Valvata sine era, Say. 

 Valvata striata, Lewis. 



depressa, pars, Kiist. 

 Valvata pupoidea, Gould. 

 Valvata humeralis, Say. 



Spurious Species. 

 Valvata arenifera, Lea. 



cinerea, Wheatley. 

 buccata, Wheatley. 



Family. AMPIILLARIID^. 



Genus. Aiupullaria. 



AmpuUaria depressa, Say. 

 Ampullaria paludosa, Say. 



hopetonensis, Lea. 



Spukious and Extralimital. 



Ampullaria borealis, Valenc. 

 Ampullaria rotiindata, Say. 



A. globosa, Hald. 

 Ampullaria urceus, Miill. 

 Ampullaria fiagelluta. Say. 

 Ampullaria Jlatilis, Reeve. 

 Ampullaria cerasum, Hanley. 

 Ampullaria miltocheilus, Reeve. 

 Ampullaria gheisbrechtii, Reeve. 

 Ampullaria fumata. Reeve. 

 Ampullaria violacea, Val. 

 Ampullaria reflexa, Sowb. 

 Ampullaria malleata, Jonas. [Ian. 

 Ampullaria paludinoides, Crist and 

 Ampullaria scalaris, D'Orb. 



The figures are generally in outline, but in connection with the 

 descriptions, will, I hope, answer their purpose. Many have been 

 copied by permission from Haldeman's Monograph, Those 

 drawn from nature are, with few exceptions, by my friend Mr. E. 

 S. Morse, of Portland, Maine. 



In the check lists printed in 1860, the genera Amnicola, Vivi- 

 para, Valvata, and Ampullaria, were placed in one family of 

 Viviparidse. That list was prepared only for the temporary 

 arrangement of the collection. It becomes necessary now to 

 adopt some system of arrangement more in accordance with the 

 recent advancement of conchological science. I have, therefore, 

 followed the system proposed in the Genera of Recent Mollusca, 

 by H. and A. Adams, copying their definitions of families and 

 genera. Their subgenera are not adopted. The characters on 

 which the families and higher divisions are based, are explained 

 in Carpenter's " Lectures on Mollusca," in the Smithsonian Re- 

 port, 1860, p. 151 et seq. 



BuELiNGTON, N. J., July, 1862. 



