hensis_, 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.

_Description._--_Color pattern_: Crown Cinnamon mixed with Smoke
Gray; upper two facial stripes black; submalar stripe Fuscous or
Fuscous Black mixed with Ochraceous Tawny; anterior margin of ear
Ochraceous Tawny; posterior margin of ear and postauricular patch
Light Buff or buffy white; hairs inside posterior part of pinna
Ochraceous Tawny; median dorsal dark stripe black; lateral pair of
dorsal dark stripes black and mixed with Tawny, frequently
brownish; median pair of dorsal light stripes white tinged with
Pale Smoke Gray; lateral pair of dorsal light stripes creamy white;
sides Tawny or Ochraceous Tawny; rump and thighs Dark Smoke Gray
strongly mixed with Cinnamon Buff; dorsal surface of tail Fuscous
Black mixed with Clay Color; ventral surface of tail Light
Ochraceous Tawny, with Fuscous Black around margin and Clay Color
around outermost edge; antipalmar and antiplantar surfaces of feet
Cinnamon or Cinnamon Buff; underparts Cinnamon Buff or Light
Ochraceous Buff. _Skull_: Size medium; moderately narrowed across
zygomata. _Baculum_: Slender; not noticeably broadened at base; tip