THE NATURAL HISTORY SURVEY. 



279 



Habitat: Found plentifully in creeks, ponds, lakes and 

 rivers, attached to pieces of floating wood, submerged vegeta- 

 tion, stones, etc. Also found attached to floating garbage, 

 such as decaying apples, vegetables, etc. 



Remarks: This is one of our most common species, and, 

 excepting L. stagnalis, is the finest and largest Limncea we have. 

 It is always characterized by a long and attenuated spire which 

 is generally twice as long as the aperture. In palustris the spire 

 and aperture are nearly equal, and the shell is wider in proper- 



FIG. 91. 



Radula of LIMN^A REFLEXA Say. (Original.) c, central tooth; 1, 

 first lateral; 11, 14, intermediate teeth; 18, 24, 29, 37, 39, marginals. 



tion to its length-than in reflexa, and the latter is very rarely 

 malleated. There is great variation in the attenuation of the 

 spire, which the figures well illustrate. The lip is sometimes 

 continuous and entirely separated from the body whorl, and 

 the whorls are swollen and separated by a deep suture, as 

 shown on plate xxxi, Fig. I. This is intermediate between the 

 typical form and variety scalaris. 



The animal is generally rather sluggish in movement, but 

 sometimes moves with considerable rapidity, especially when 

 feeding. The species is as widely distributed in the present 

 area as pahistris. 



Dr. Howard N. Lyon has raised this species from the egg 



