_Thomomys talpoides columbianus_ Goldman, Jour. Mamm., 20:234, May 15, 1939. _Type._--Obtained at Touchet, Walla Walla County, Washington, by C. P. Streator on September 10, 1890; type in United States National Museum. _Racial characters._--Larger and brighter in color than _devexus_. Near ochraceous orange in color. _Measurements._--Five male and three female topotypes average, respectively: total length 213, 209; length of tail 60, 58; hind foot 29, 28. _Distribution._--Walla Walla County, between the Snake River and the Oregon boundary and from the Columbia River east to the Columbia County line. =Thomomys talpoides aequalidens= Dalquest _Thomomys talpoides aequalidens_ Dalquest, Murrelet, 23:3, May 14, 1942. _Type._--Obtained at Abel Place, 2,200 ft., 6 miles south-southeast of Dayton, Columbia County, Washington, by S. H. Lyman, on April 6, 1934; type in Museum of Vertebrate Zoölogy. _Racial characters._--Large size, very dark color. _Measurements._--The average of four male topotypes and the measurements of one female topotype are, respectively: total length 202, 201; length of tail 57, 59; hind foot 26, 27. _Distribution._--Southeastern Washington east of the range of _columbianus_ and north of the higher parts of the Blue Mountains. =Thomomys talpoides wallowa= Hall and Orr _Thomomys quadratus wallowa_ Hall and Orr, Proc. Biol. Soc. Washington, 46:41, March 24, 1933. _Thomomys talpoides wallowa_ Goldman, Jour. Mamm., 20:234, May 15, 1939. _Type._--Obtained at Catherine Creek, 7 miles east of Telocaset, 3,500 ft., Union County, Oregon, by R. T. Orr on June 29, 1932; type in Museum of Vertebrate Zoölogy. _Racial characters._--Similar to _devexus_ but much darker. Similar (in Washington) to _aequalidens_ but much smaller. _Measurements._--Four males and 4 females from Mountain Top and Stay-a-while Spring, Columbia County, average, respectively: total length 191, 180; length of tail 56, 52; hind foot 26, 25. _Distribution._--The higher parts of the Blue Mountains. _Remarks._--Washington specimens referred to this race are intermediate between _wallowa_ and _aequalidens_ but are colored like _aequalidens_. =Thomomys talpoides fuscus= Merriam _Thomomys clusius fuscus_ Merriam, N. Amer. Fauna, 5:69, July 30, 1891. _Thomomys myops_ Merriam, Proc. Biol. Soc. Washington, 14:112, July 19, 1901 (type from Conconnully, Okanogan County, Washington). _Thomomys fuscus fuscus_ Bailey, N. Amer. Fauna, 39:126, November 15, 1915. _Thomomys talpoides fuscus_ Hall and Dalquest, Murrelet, 20:4, April 30, 1939.