_Thomomys bottae absonus_ Hall and Davis, Proc. Biol. Soc. Washington, 47:52, February 9, 1934; Goldman, Proc. Biol. Soc. Washington, 48:156, October 31, 1935. _Thomomys perpallidus aureus_ Bailey, N. Amer. Fauna, 39:75, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):100, June, 1927. _Type._--Male, adult, skin and skull, No. 250016, U. S. National Museum (Biological Surveys Collection); Jacobs Pools, Houserock Valley, 4,000 ft., Coconino County, Arizona; June 7, 1931; collected by E. A. Goldman; original number 23569 (after Goldman, type not seen). _Range._--Southern Utah in Kane and Garfield counties, in the drainages of Kanab Creek, Johnson Creek, Paria River and Escalante River. _Diagnosis._--Size medium (see measurements). Color: Upper parts Ochraceous Buff mixed with dusky; sides and underparts Light Ochraceous Buff; chin, nose, cheeks and top of head grayish black; postauricular patches black mixed with buff; front feet, hind feet, inguinal region and distal third of tail white. Skull: Nasals relatively long; rostrum narrow; ascending processes of premaxillae narrow; extension of premaxillae posterior to nasals short; lambdoidal and sagittal crests poorly developed; zygomatic arches light; jugals nearly straight; palate narrow; molariform teeth small. _Comparisons._--Compared with topotypes of _Thomomys bottae trumbullensis_, _absonus_ differs in: Size smaller. Color: Markedly lighter throughout. Skull: Smoother, less angular; zygomatic arches weak as opposed to robust; nasals more convex as viewed laterally; extension of premaxillae posterior to nasals less; ascending processes of premaxillae narrower; palate narrower; palatal pits shallower; rostrum narrower; molariform teeth smaller. For comparisons of _absonus_ with _Thomomys bottae aureus_ see account under that form. Among named races of _Thomomys bottae_, _absonus_ most closely resembles _planirostris_, but can be distinguished from the topotypes as follows: Size markedly smaller. Color: Lighter, more buffy throughout. Skull: Smaller, less ridged and more nearly flat; nasals convex as opposed to flat; extension of premaxillae posterior to nasals less; width of ascending processes of premaxillae less; zygomatic arches weaker; palate narrower; alveolar length of upper molar series shorter; tympanic bullae more inflated ventrally; molariform teeth smaller and lighter. _Remarks._--One specimen from Kanab is an intergrade between _trumbullensis_ and _absonus_. The majority of its characters are with _absonus_ to which it is referred (see Hall and Davis, 1934:52). Two specimens from Escalante are intergrades between _absonus_ and _dissimilis_, but are referable to _absonus_. _Specimens examined._--Total, 3, distributed as follows: _Garfield County_: Escalante, 5,258 ft., 2 (B. Y. U.), _Kane County_: Kanab, 4,925 ft., 1 (M. V. Z.). =Thomomys bottae alexandrae= Goldman