80 HELICID^. 



appears to have been overlooked until lately, when it was 

 mistaken for Mr. Say's species, from which it differs very 

 considerably, resembling, indeed, Succinea oblonga,J)Ta.^. 

 more than any other species. 



It does not offer any considerable variation except in 

 size, and the greater or less expansion of the aperture, 

 the latter variation affecting its conical figure. When 

 the anterior part of the aperture is not much contracted 

 the body whorl has the appeai-ance of being compressed, 

 and the aspect of the shell is long and narrow. The 

 shell is particularly thin and delicate, so that the color 

 of the animal is seen through it. The quantity of the 

 dotting of the animal varies very much, in some being 

 so thick as to give the whole animal a dark gi-ay color, in 

 others so sparse as to leave them almost white. It ap- 

 pears to prefer the margins of water on wet and marshy 

 ground, especially where there are fragments of wood 

 saturated with water. We are not aware of its having 

 been found in any other situation. It is also frequently 

 taken on the leaves of flags, (/n's versicolor,) on the stems 

 of Pontederia and other aquatic plants. 



It deposits its eggs, to the number of about twenty, 

 enveloped in a mass of tlun transparent gelatme, at the 

 foot of aquatic plants. These gelatinous masses are 

 very numerous in this latitude, in the warm days of 

 June. The eggs are oval and transparent. 



