I have seen only one specimen from the type locality. It is one of the series on which Merriam (1901:112) based his original description. In addition, I have studied several large series of near topotypes. From the material at hand, and from Merriam's description (_loc. cit._), I regard the animals on which the name _uinta_ was based as intergrades between _Thomomys talpoides ravus_, the race to the northeast, on the one hand and the animals of the western and southern parts of the Uinta Mountains on the other hand. The affinities of the type series are with the animals from the latter area which are here all referred to _uinta_. _Specimens examined._--Total, 41, distributed as follows: _Summit County_: 2 mi. S junction Bear River and Haydens Fork, 2 (C. M.); N base, Gilbert Peak, 10,000 ft., 1 (U. S. N. M.); Smith and Moorehouse Creek, 2; Bald Peak, 25 mi. NE Kamas, 15 (8, M. V. Z.; 6, C. M.). _Duchesne County_: Petty Mountain, 15 mi. N Mountain Home, 9,500 ft., 6 (C. M.). _Wasatch County_: Wolf Creek Pass, 18 mi. NW Hanna, 1 (U. S. A. C.); Lost Lake, Uinta Mountains, 10 (B. Y. U.); Current Creek, Uinta Mountains, 1 (U. S. N. M.). _Carbon County_: Forks, Sunnyside, 9,000 ft., 3. _Additional records._--_Summit County_: Uinta Mountains, 6 (see Bailey, 1915:114). =Thomomys talpoides pygmaeus= Merriam _Thomomys pygmaeus_ Merriam, Proc. Biol. Soc. Washington, 14:115. July 19, 1901. _Thomomys talpoides pygmaeus_ Davis, The Recent mammals of Idaho, p. 252, The Caxton Printers, Ltd., Caldwell, Idaho, April 5, 1939. _Type._--Male, adult, skin and skull, No. 55251, U. S. National Museum (Biological Surveys Collection); 10 mi. NE Montpelier, in open sagebrush of Transition Zone, 6,600 ft., Bear County, Idaho; July 29, 1893; collected by Vernon Bailey: original number 4150 (after Merriam, type not seen: see, also, Bailey, 1915:109). _Range._--Limited to Daggett County. _Diagnosis._--Size: Small (see measurements). Color: Upper parts near Bister slightly mixed with black, grading over sides and flanks to Ochraceous Buff on underparts; postauricular patches small and dusky; hind feet white; front feet dusky, being white only at base of claws; chin and nose dusky; tail brown, lighter below and tipped with white. Skull: Very small, slender and smooth; nasals short and slender; zygomatic arches weak and not widely spreading; rostrum narrow; extension of premaxillae posterior to nasals short; parietal ridges hardly noticeable; interparietal large; extension of supraoccipital posterior to lambdoidal suture long; tympanic bullae actually small, but relatively large; basioccipital narrow; interpterygoid space narrow and acutely angled; upper incisors markedly recurved; molariform teeth relatively large.