514 U. S. NATIONAL MUSEUM BULLETIN 205 



sis in region of Manitoba-Saskatchewan boundary, Canada (Anderson, Nat. 

 Mus. Canada Bull. 102 (1946) , p. 34, Jan. 24, 1947) . 



Onychomys leucogaster missouriensis (Audubon and Bachman) * 



1851. Mus missouriensis Audubon and Bachman, The viviparous quadrupeds 



of North America, vol. 2, p. 327, and pi. 100, No. 20. 

 1914. Onychomys leucogaster missouriensis Hollister, Proc. U. S. Nat. Mus., 



vol. 47, p. 438, Oct. 29, 1914. 

 Type Locality. — Fort Union, near present town of Buford, Williams County, 

 N. Dak. Range. — Northeastern Wyoming, western North Dakota (V. Bailey, 

 North Amer. Fauna No. 49 (December 1926), p. 84, Jan. 8, 1927), and eastern 

 and northern Montana; north to southeastern Alberta (Calgary, Medicine Hat, 

 Little Sandhill Creek, near Steveville) and southern Saskatchewan (Carlton, 

 Dundurn, Indian Head, Last Mountain Lake, Osier, Weyburn, Wood Mountain, 

 and east of Frenchman River) ; zonal range, chiefly arid Transition and Upper 

 Sonoran (Anderson, Nat. Mus. Canada Bull. 102 (1946), p. 134, Jan. 24, 1947) ; 

 east to Glen Ullin, N. Dak.; west and south along Missouri River to Bozeman, 

 Mont.; and southwest along branches of Powder and Little Missouri Rivers into 

 northeastern Wyoming. 



Onychomys leucogaster arcticeps Rhoads* 



1898. Onychomys arcticeps Rhoads, Proc. Acad. Nat. Sci. Philadelphia, vol. 

 50, p. 194, May 3, 1898. 



1914. Onychomys leucogaster arcticeps Hollister, Proc. U. S. Nat. Mus., vol. 

 47, p. 439, Oct. 29, 1914. 



Type Locality. — Clapham, Union County, N. Mex. Range. — Upper Sonoran 

 Great Plains, from Wyoming and South Dakota to Texas. North to Big Horn 

 River in Wyoming and to Cheyenne River in South Dakota; east to Bonesteele, 

 Gregory County, near Missouri River in South Dakota; western third of Kansas, 

 intergrading with breviauritus in Meade and Ellis Counties, Kansas (Black, 

 Kansas State Board Agric. Thirtieth Biennial Rept., 1935-1936, p. 187, 1937) ; 

 south to Fort Lancaster, southwestern Pecos County, Tex.; and west to Bear River 

 Divide in southwestern Wyoming, western edge of Great Plains (Golden, Salida, 

 and Westclifie) in eastern Colorado, Panhandle of Oklahoma (Blair, Amer. Midi. 

 Nat., vol. 22, No. 1, p. 117, July 1939), and Upper Sonoran plains of eastern 

 New Mexico, including Pecos River Valley from Santa Rosa to Carlsbad, and 

 grading insensibly into ruidosae farther west (V. Bailey, North Amer. Fauna 

 No. 53 (December 1931) , p. 139, Mar. 1, 1932) . 



Onychomys leucogaster brevicaudus Merriamf * 



1891. Onychomys leucogaster brevicaudus Merriam, North Amer. Fauna No. 5, 

 p. 52, July 30, 1891. 



Type Locality. — Blackf oot, Bingham County, Idaho. Range. — Southern Idaho, 

 extreme southwestern Wyoming, northwestern Utah, and west across northern half 

 of Nevada into eastern California. Semiarid southern Idaho from Owyhee County 

 east into Wyoming and north to Pahsimeroi Valley, Custer County (Davis, 

 The Recent mammals of Idaho, p. 278, Apr. 5, 1939) ; in Utah, east to Wasatch 

 foothills (Hall, Univ. California Publ. Zool., vol. 37, No. 1, p. 5, Apr. 10, 1931) 

 and south to Sevier County (Stanford, Journ. Mamm., vol. 12, No. 4, p. 360, 



