LIMNZA. 97 
specimen. Its principal distinctive feature is 
the very convex body whorl, which is almost 
shouldered, and itis also umbilicate; but I 
am inclined to believe these the result of acci- 
dental distortion rather than specific differ- 
ences, and in all other respects it corresponds 
with proxima. 
13. LIMNA PALUSTRIS, Miller. 
Plate 17, fig. 4. 
L. fragilis (not of Linn.), Hald. Monog., 20, 53, t,.6, and 
: t. 15, fig. 1. 
L. umbrosus, Hald., t. 7, figs. 4, 5. 
L. expansa, Hald. Monog., 29, t. 9, figs. 6, 8. 
L. Sumassii, Baird. Plate 17, fig. 5. 
This species extends across the continent 
through the great lakes and their tributaries 
from Lake Champlain. It is very numerous 
in nearly all the streams of the West Coast, 
and extends southwards to New Mexico. It 
is acommon European species. I figure (fig. 
4) an angular monstrosity of this species from 
Mountain Lake, Cal. 
(71) 
