VALVATA. 



13 



The outline figure published by Say and copied iu my figure IG 

 is not very satisfactory, nor have I ever seen specimens referred to 

 this species which can easily be distinguished from ecarinate forms 

 of V. tr^icarinata. Fig. 11 is a view of the animal copied from 

 Haldeman. Kirtland quotes it from Ohio. 



I give also a figure of a specimen of V. sMata furnished by 

 Dr. Lewis. I have no doubt of its identity with V. sincera. The 

 name is preoccupied by Philippi, Enum. Moll., p. 15T. Dr. Lewis' 

 description is as follows: — 



Valvata striata. — Shell conical, depressed, nmbilicate ; aper- Fig. 18. 

 ture round ; epidermis brown and very regularly striate. Has tf??^^ 

 all'the other features of sincera except color and translucency. ^!^_) 



Animal not observed. Very rarely seen. Of several hundred y. striata. 

 specimens of Valvata only seven were this species. {Lewis.) 



No. 8936 of the collection was labelled V. sincera by Dr. R, 

 E. Griffith. 



Valvata piipoidea, Gould. — Shell small, elongate-ovate, opaque, 

 chestnut-colored, when divested of the rough, dirty pigment which usually 

 adheres closely to it ; whirls foiir or five, minutely wrinkled, 

 the posterior one small and flattened so as to form an obtuse Fig. 19. 

 apex; the others cylindrical, and so partially in contact as to A 

 expose about one-half of the cylinder; the last entirely dis- ^^^ 

 joined from the preceding one for at least the half of a revolu- „ , 

 tion ; aperture circular, lip simple and sharp ; on looking at the pupoidea. 

 shell from below, no umbilical opening is found; operculum 

 horny, apex central, elements concentric. Length .1, breadth 3-40 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 tentacles, 

 bilobed 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 whirl, dilated into two 

 acute angles in front, light drab-color ; respiratory organ occasionally pro- 

 truded 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 



