FAMILY LYMN.EIU.'E 77 



California ! Oregon ! Seattle, Wash. ! Sumas Lake, British Colum- 

 bia ; Vancouver Island ! headwaters of the Yukon ! Lake Marsh ! 

 Lake Lindeman ! Old Fort Yukon, Alaska ! Saccatalontan and Nu- 

 lato ! Lower Yukon, and in the Yukon delta ! Dall River ! north of the 

 Yukon in Alaska. Point Romanof, Norton Sound, Alaska ! Avacha 

 Bay, Kamchatka ! etc. 



This well known species is almost universally distributed in the 

 quiet waters of boreal America, and in the Pleistocene marls. The 

 distinctions which have been relied on to separate L. haydeni Lea, 

 and L. expansa Haldeman, are due to pathologic mutations. L. 

 nuttalliana and proxinia Lea, are trivial varieties. 



Lymnaea (Stagnicola) reflexa .Say. 



Lyiniu-us n-ffc-xits Say, Journ. Acad. Nat. Sci. Phila., II, p. 167, 182 1 ; .A.m. 



Conch., IV, pi. XXXI, fig. 2, 1832 (Lakes Erie and Superior). 

 Lhnneus I'/oniralus Sav, Journ. Acad. Nat. Sci. Phila., 11, 



p. 167, 1821 ; not of Urapamaud, 1805. 

 IJmneus umhrosus Sav, Am. Conch., iv, pi. 31, fit;, i, 



1832 (new name for doiii^atus Say). 

 Limnaa exilis Le.a, Trans. Am. Phil. Soc, v, p. 114, pi. 



XIX, fig. 82, 1837 (pathologic mutation). 



Ratig-e. — Northern LTnited States and Canada. 



Prairie Lake, near Red River of the North ; and 

 Beaver Creek, Manitoba. 



This species barely crosses the boundarj' and may- 

 be one of those captured bv the northward drainage '^ !^ 



' - .... . f"^" re/iexa bav. 



when the headwaters of the Mississippi were inter- 

 rupted and turned northward by the changes in the land levels of this 

 region which have been elucidated by the late General G. K. 

 \\'arren. 



Lymnaea (Stagnicola) catascopium Say. 



Lymnaa catascopium Sav, Nicholson's Encycl., Am. ed., 11 (no pagination), 



pi. 2, fig 3, 18 17 (Delaware River). 

 Lmhuitus catascopium 'i>\\. Am. Conch., vi. pi. 55, fig. 2, 1832. 

 Lymnea cornea Valenciennes, in Humboldt and Bonpland, Rec. d'obs. de 



Zool., 11, p. 251, 1832. 

 Limncea sumassi Baird, Proc. Zool. Soc. London. 1863, p. 68. — Binnev, 



Land and Fw. Sh. N. Am., 11, p. 43, fig. 57 (not fig. 56), 1865 (British 



Columbia). 



Range. — L. catascopium ■ Northern United States to the Rocky 

 Mountains, Canada and northward ; var. sumassi : Idaho, Washing- 

 ton and British Columbia. 



Ottawa, Canada ! Ungava, Labrador ! Lake Winnipeg, Manitoba ! 

 Hudson Bay drainage of Keewatin ! Moose River at Moose Factory, 



