196 Fresh-Water Shells. 



Genus LIMN^A, Lam. 



Shell thin, ohlong or turreted, last whorl large ; aperture largt^ 

 rounded before, narrowed and acute behind, outer lip sharp, inner 

 lip forming a fold on the pillar, and usually spreading over it. 

 Animal with short, triangular tentacula. 



LiMNiEA StAGNALIS. (LiNN.) 



Fig. 1. 



a 1/ 



Fig. 2. 



Fig. 1. — The empty shell. 

 Fig. 2, A. — The animal in the shell. 

 B. — Mass of eggs magnified. 



Our shell is about two inches long, the aperture being nearly 

 one-half of the total length. It consists of five or six whorls, of 

 which the four uppermost are slender and tapering to an acute 

 point. The body of the Avhorl is as large as represented in the 

 figures. There is a conspicuous fold on the inner lip. 



This is by far the largest Limnea known in Canada, and is 

 easily recognized by its superior size alone. * 



* The remainder of this article is copied from Gould's Invertebrata of 

 Massachusetts. 



