NORTH AMERICAlsr LAND MAMMALS. 207 



*Lemmus trimucronatus (Richardson). 



1825. Arvicola trimucronata Richardson, Journ. Parry's Sec- 

 ond voyage, app., p. 309. 

 1900. Lemmus trimucronatus Stone, Proc. Acad. Nat. Sci. 



Philadelphia, p. 35. March 24, 1900. 

 Type Locality. — Point Lake, Mackenzie, Canada. 



t*Lemmus yukonensis Merriam. 



1900. Lemtnus yuTconensis Merriam, Proc. Washington Acad. 



Sci., vol. 2, p. 27. March 14, 1900. 

 Type Locality. — Charhe Creek, Yukon River, Alaska. 



Genus DICROSTONYX Gloger. 



1841. Dicrostonyx Gloger, Gemeinn. Hand- u. Hilfsbiich d. 

 Naturgesch., p. 97. Type, an American species, probably Mus 

 Tiudsonius Pallas. 



*Dicrostonyx hudsonius hudsonius (Pallas). 



1778. Mus hudsonius Pallas, Nov. Sp. Quadr. Glir. Ord., p. 

 208. 



1897. Dicrostonyx hudsonius Bangs, Proc. Biol. Soc. Wash- 

 ington, vol. 11, p. 237. September 17, 1897. 



Type Locality. — Labrador. 



*Dicrostonyx hudsonius alascensis Stone. 



1900. Dicrostonyx hudsonius alascensis Stone, Proc. Acad. Nat. 



Sci. Philadelphia, p. 37. March 24, 1900. 

 Type Locality. — Point Barrow, Alaska, 



*Dicrostonyx hudsonius grcBnlandicus (Traill). 



1823. Mus groenlandicus Traill, Scoresby's Journ. Voy. northern 



Whale-Fishery, p. 416. 

 1911. Dicrostonyx hudsonius groRnlandicus Jacobi, Abhandl. u. 

 Berichte k. Zool. u. Anthrop.-Ethnol. Mus. Dresden, vol. 13, 

 1908, No. 4, p. 9. 1911. 

 Type Locality. — ^Jameson's Land, Greenland. 



t*Dicrostonyx nelsoni Merriam. 



1885. Cuniculus torquatus True, Proc. U. S. Nat. Mus., vol. 7 



(1884), p. 596. 1885. (Part.) 

 1900. Dicrostonyx nelsoni Merriam, Proc. Washington Acad. 



Sci., vol. 2, p. 25. March 14, 1900. 

 Type Locality. — St. Michael, Alaska. 



t*Dicrostonyx richardsoni Merriam. 



1900. Dicrostonyx richardsoni Merriam, Proc. Washington 



Acad. Sci., vol. 2, p. 26. March 14, 1900. 

 Type Locality. — ^Fort Churchill, west shore of Hudson Bay, 



Keewatin, Canada, 



