288 PALUDINIDiE. 



Valvata pupoidea.* 



Fig. 155. 



Shell minute, elevated, chestnut colored ; whorls four or five, the last nearly 

 disjoined. 



Valvata pnpoidea, Gould, Am. Journ. Sc. 1st ser. xxxviii. 196, 1840; Inv. Mass. 226, 

 fig. 155; Otia, 180. — Haldeman, Mon. 10, pi. 1, figs. 11-13. — Dk Kay, N. Y. 

 Moll. 119. — Chenu, Man.de Conch, ii. 311, fig. 2230. — Anonymous, Can. Nat. 

 ii. 214, fig.— W. G. BiNXEY, L. and Fr. Shells, iii. 13, fig. 19 (1865). 



Shell small, elongated-ovate, opaque, chestnut colored, when di- 

 vested of the rough, dirty pigment which usually adheres closely to 

 it ; whorls four or five, minutely wrinkled, the posterior one 

 ^'"ifi^^ small and flattened so as to form an obtuse apex ; the others 

 ^ cylindrical, and so partially in contact as to expose about 

 V. pupoi- one half of the cyHnder ; the last entirely disjoined from the 

 f^red prcceding one for at least the half of a revolution ; aperture 

 circular, lip simple and sharp ; on looking at the shell from 

 below, no umbilical opening is found ; operculum horny, apex cen- 

 tral, elements concentric. Length, one tenth of an inch ; breadth, 

 three fortieths of an inch. 



Found at Fresh Pond and other ponds, on stones and submerged 

 sticks ; and has been for many years in our cabinets marked as a 

 Paludina. 



Animal very active ; head proboscidiform, half as long as the ten- 

 tacles, bi-lobed in front, dark, terminated with light ; tentacles 

 rather stout, light drab colored, with a line of silvery dots on the 

 upper side, over the large, black eyes ; foot tongue-shaped, as long 

 as the first whorl, dilated into two acute angles in front, light drab 

 color ; respiratory organ occasionally protruded to half the length 

 of a tentacle on the right side. 



This species is widely distinguished from all other described ones 

 by its minuteness, its color, its elongated form, and its want of an 

 umbilicus ; of which characters the last two seem to arise from the 

 loose manner in which the whorls are united. 



Found also in Connecticut (Linslcy) ; District of Columbia (Gi- 

 rard) ; Maine QMig-hch) ; and Canada (Can. Nat.'). 



* This species is made the type of a new genus, Li/ogi/rus, by Professor Gill (Proc. Ac. 

 Nat. Sci. Phil. 1863). It does not appear to me that there are sufficient grouuda for be- 

 lieving it distinct. — VV. G. B. 



