56 LAND AND FRESH WATER MOLLUSKS 



have been examined are so great that it is probably better to await a 

 more thorough knowledge of all the species, in the light of which we 

 can judge better whether this character has any systematic value or 

 not. Our American species resemble one another so closely that it 

 seems hardly likely that there are any fundamental differences between 

 them. 



Succinea oregonensis Lea. 



Succinea oregonensis LEA, Proc. Am. Phil. Soc., p. 32, 1841 ; Trans. Am. 

 Phil. Soc., ix, p. 5, 1844. BINNEY, Terr. Moll., n, p. 77, pi. LXVII, 

 fig. 2, 1851. TRYON, Am. Journ. Conch., u, p. 235, pi. (n) xvn, 

 fig. 18, 1866. BINNEY, Land and Fw. Sh. N. Am., i, p. 270, fig. 485, 

 1869. 



Range. California (to 6,500 feet alt .) , Oregon, Washington, and 

 British Columbia. 



Victoria, B. C. ! Wallawalla, Wash. ! 



This species on the Pacific Coast takes the place in the fauna 

 occupied in the East by S. avara Say, which it much resembles. 

 The S. ' oregonensis ' reported from Winnipeg by Hanham was 

 probably a variety of a-vara. The surface has a silky unpolished 

 appearance, from the very fine close wrinkles with which it is covered, 

 and which are characteristic. 



Succinea retusa Lea. 



Succinea retusa LEA, Trans. Am. Phil. Soc., v, p. 117, pi. xix, fig. 86, 1837. 

 W. G. BINNEY, Land and Fw. Sh. N. Am., i, p. 256, fig. 454, 1869. 

 Succinea ovalis GOULD, Inv. Mass., p. 194, fig. 125, 1841, not of Say, 1817. 

 Succinea haydeni var. minor W. G. BINNEY, Land and Fw. 

 Sh. N. Am., i, p. 256, 1869. TRYON, Am. Journ. 

 Conch., n, p. 236, 1866. 



Succinea decampi TRYON, Am. Journ. Conch., n, p. 237, 

 pi. xvii, fig. 23, 1869. BINNEY, /. c., p. 257. 



Range. Northern United States, from Kentucky 

 FIG. 38. Sue- northward to Canada and British America. 

 cinea retusa Lea. In Manitoba at Carberry, Lake of the Woods and 

 Pembina Mountain ; in Alberta at Laggan and Red 

 Deer. Ungava, Labrador ! James Bay at Moose Factory ! Lower Sas- 

 katchewan near Lake Winnipeg ! Norway House ; York Factory ; 

 Fort Resolution, Great Slave Lake ! Yukon River near old Fort 

 Yukon, Alaska ! Stewart River, Yukon district ! Dall River, north of 

 the Yukon ! Duncan Bay, Discovery Passage, British Columbia. 



A widespread and abundant species identified by comparison of the 

 typical specimens or cotypes furnished by the author to the National 

 Museum. 



