26 



LAND AND FRESH WATER MOLLUSKS 



Astoria, Oregon! Victoria, Vancouver Island; Chilliwak Lake, 

 British Columbia. 



A variety megasoma, more than four times the size of the typical 

 germana, hut otherwise quite similar, is occasionally found; some 

 from northern California (Stearns) are in the National Museum. 



Polygyra monodon Rackett. 



Helix monodon Rackett, Trans. Linnean Soc, xm, p. 42, pi. v, fig. 2, 1822. 

 — Morse, Am. Nat., 1, p. 151, figs. 12, 13, 1867. — 

 Binney, Land and Fw. Sh. N. Am., i, p. 120, figs. 200- 

 205, 1869. 



Range. — Eastern United States, east of the plains 

 region, from Texas to Minnesota and northward. 

 Moose Factory, James Bay ! 



Fig. 3. Poly- 

 gyra monodon 

 Rackett. 



Polygyra albolabris Say. 



Helix albolabris Say, Nicholson's Encycl., 1st Am. ed., pi. 1, fig. 1, 18 17 ; Am. 

 Conch., 11, pi. xii, 1 83 1. — Morse, Am. Nat., i, p. 6, pi. 1, figs. 1-11, 

 1867. — Binney, Land and Fw. Sh. N. Am., i, p. 136, figs. 229-232, 

 1869. 



Range. — Eastern United States, from Georgia and Arkansas north- 

 ward to the Saskatchewan. 



Figs. 4-6. Polygyra albolabris Say, \. 



Lake Superior region ; Lake Winnipeg, Manitoba ; and northward 

 to the Saskatchewan River (Richardson). 



