LIMNiEA. 97 



specimen. Its principal distinctive feature is 

 the very convex body whorl, which is almost 

 shouldered, and it is 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. LIMN^A PALUSTRIS, Muller. 



Plate 17. Eg. 4. 



L. fragilk (not of Linn.), Hald. Monog., 20, 53, t. 6, and 



t. 15, fig. 1. 



L. umhrosus, Hald., t. 7, figs. 4, 5. 



L. expansa, Hald. Monog., 29, f. 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 numeroue" 

 in nearly all the. streams of the West Coast, 

 and extends southwards to New Mexico. It 

 is a common European species. I figure (fig. 

 4) an angular monstrosity of this species from 

 Mountain Lake, Cal. 



(71) 



