Mean (5) | 35.2 | 18.8 | 15.5 | 10.8 | 226 | 96.0 | 5.20 | 18.29 | Min. [Male] | 34.7 | 18.4 | 15.2 | 10.1 | 215 | 93.0 | 5.03 | 17.80 | Max. | 36.8 | 19.4 | 16.2 | 11.5 | 232 | 115.0 | 5.53 | 19.36 | | | | | | | | | | Mean (6) | 35.7 | 19.1 | 15.6 | 10.9 | 226 | 98.0 | 5.28 | 18.67 | Min. [Female] | 35.1 | 18.8 | 15.1 | 10.3 | 215 | 89.0 | 5.06 | 18.09 | Max. | 36.5 | 19.5 | 16.0 | 11.5 | 231 | 105.0 | 5.58 | 19.35 | --------------+------+------+------+------+-----+-------+------+-------+ Eutamias amoenus (J. A. Allen) _Diagnosis._--Size medium; over-all tone of upper parts often grayish olive; baculum small or medium, slender; tip of baculum 30 to 38 per cent of length of shaft; skull medium, narrow across zygomata. _Comparisons._--From _E. dorsalis utahensis_, the only subspecies of this species in Wyoming, _E. amoenus luteiventris_ differs in: Dorsal light and dark stripes distinct; over-all tone of upper parts less grayish (more tawny); tip of baculum less than 38 per cent of length of shaft in adult specimens. From _E. umbrinus fremonti_, the only subspecies of this species which occurs in the same area with _E. amoenus_ in Wyoming, _E. a. luteiventris_ differs in: Smaller size; tawny underparts; base of baculum not noticeably widened. For comparisons with _E. minimus_ see the account of that species. Eutamias amoenus luteiventris (J. A. Allen) _Tamias quadrivittatus luteiventris_ J. A. Allen, Bull. Amer. Mus. Nat. Hist., 3:101, June, 1890. _Eutamias amoenus luteiventris_, Howell, Jour. Mamm., 3:183, August 4, 1922. _Type._--Male, adult, skull and skin, No. 11991/37996 (NM); from "Chief Mountain Lake" [Waterton Lake], 3-1/2 mi. N United States-Canadian Boundary, Alberta; obtained on August 24, 1874, by Elliot Coues; original No. 4596. _Diagnosis._--General tone of upper parts ochraceous; underparts strongly buffy; tip of baculum in adult specimens, more than 30 per cent and less than 38 per cent of length of shaft.