566 U. S. NATIONAL MUSEUM BULLETIN 205 



Type Locality. — Point Lake, Mackenzie District, Northwest Territories, 

 Canada. Range. — Boreal America, in the east from Hudson Strait north to 

 northern Baffin Island (Admiralty Inlet, Pond Inlet, Strathcona Sound) ; and 

 southern part of Somerset Island near Fort Ross, Bellot Strait; west of Hudson 

 Bay north of about lat. 62° N. to near eastern end of Great Slave Lake, Clinton 

 Colden Lake, west and north to Cape Bathurst and Cape Kellett on west coast 

 of Banks Island (Anderson, Nat. Mus. Canada Bull. 102 (1946) , p. 147, Jan. 24, 

 1947). 

 Lemmus trimucronatus alascensis Merriamf* 



1884. Myodes obemis True, Proc. U. S. Nat. Mus., vol. 7 (App., Circ. 29), 



p. 596, Nov. 29, 1884. (Part.) 

 1900. Lemmus alascenis Merriam, Proc. Washington Acad. Sci., vol. 2, p. 26, 



Mar. 14, 1900. 

 1900. Lemmus yukonensis Merriamf, Proc. Washington Acad. Sci., vol. 2, 



p. 27, Mar. 14, 1900. (Charlie Creek, Yukon River, Alaska.) 

 1937. Lemmus trimucronatus alascensis Anderson, Mammals and birds of the 

 western Arctic District, Northwest Territories, Canada, in Canada's Western 

 Northland, Dept. Mines and Resources, Ottawa, p. 110, July 9, 1937. (Lem- 

 mus sibiricus chrysogaster, see Ellerman and Morrison-Scott, Checklist of 

 Palaearctic and Indian Mammals, 1758 to 1946, Publ. Brit. Mus. (Nat. 

 Hist.), p. 656, Nov. 19, 1951, and Lemmus trimucronatus alascensis are 

 regarded as related by Ognev, The mammals of Russia (U.S.S.R.) and ad- 

 jacent countries, Publ. Acad. Sci. U.S.S.R., vol. 6, p. 470, 1948.) 

 Type Locality. — Point Barrow, Alaska. Range. — -Alaska, north of lat. 62° N., 

 northwestern Arctic Canada, including northern part of Yukon and northwestern 

 part of Mackenzie District, Northwest Territories, east to Cape Bathurst. 



Lemmus trimucronatus helvolus (Richardson) * 



1828. Arvicola (Lemmus) helvolus Richardson, Zool. Journ., vol. 3, p. 517. 



1908. Lemmus helvolus Preble, North Amer. Fauna No. 27, p. 182, Oct. 26, 

 1908. 



1944. Lemmus trimucronatus helvolus Davis, Murrelet, vol. 25, No. 2, p. 22, 

 Sept. 19, 1944. 



Type Locality. — Near headwaters of one of southern tributaries of Peace River, 

 or between there and Jasper House region, Alberta, Canada (Preble, loc. cit.). 

 Range. — Rocky Mountains region of northwestern Alberta and in British Colum- 

 bia from headwaters of Peace River, Babine Mountains, Omineca Mountains, 

 Stikine Mountains, and Coast Mountains as far south as Stuie at head of Bella 

 Coola River, and Rainbow Mountains (about lat. 52°30' N.), and north to Tan- 

 talus and Teslin Lake in southern Yukon (Anderson, Nat. Mus. Canada Bull. 102 

 (1946), p. 147, Jan. 24, 1947). 



Lemmus trimucronatus minusculus Osgoodf * 



1904. Lemmus minusculus Osgood, North Amer. Fauna No. 24, p. 36, Nov. 



23, 1904. 

 1944. Lemmus trimucronatus minusculus Davis, Murrelet, vol. 25, No. 2, p. 23, 

 Sept. 19, 1944. 



