er facial stripe Sepia; ocular stripe
Chaetura-Drab; submalar stripe Fuscous Black mixed with Sayal
Brown; ear black; anterior margin of ear Mars-Yellow,
posterior margin grayish white; hairs inside posterior
portion of pinna Dresden-Brown; postauricular patch Pale
Smoke Gray; median dorsal dark stripe black; lateral dorsal
dark stripe black mixed with Sayal Brown; outermost dorsal
dark stripe obsolete, Buckhorn-Brown mixed with black; median
pair of dorsal light stripes grayish mixed with
Buckhorn-Brown; outer pair of dorsal light stripes creamy
white; sides Buckhorn-Brown; rump Pale Smoke Gray mixed with
Saccardo's Umber; dorsal surface of tail black mixed with
Buckhorn-Brown; ventral surface of tail Sayal Brown;
outermost edge of tail Light Buff; antipalmar surface of
forefeet Warm Buff; antiplantar surface of hind foot
Ochraceous-Tawny; underparts creamy white with dark underfur.
_Skull_: Large, with strong zygomata; braincase well
inflated. _Baculum_: As in _E. u. umbrinus_.

_Comparisons._--From _E. u. umbrinus_, the subspecies from
the Uinta and northern Wasatch Mountains in Utah, _E. u.
fremonti_ differs in: Sides darker; antiplantar surfaces of
feet darker; postauricular patch grayer; crown more grayish;
skull slightly larger.

From _E. ruficaudus ruficaudus_, the species and subspecies
from western Montana, _E. u. fremonti_ differs in: General
tone of upper parts, sides, underside of tail, and feet, all
darker in coloration; baculum shorter and proportionally
twice as wide at base.

For comparison with _E. u. montanus_, see the account of that
subspecies.

_Remarks._--The geographic ranges of _E. umbrinus fremonti_ and
_E. ruficaudus ruficaudus_ are allopatric and no specimens have ever
been taken in the intermediate area to indicate whether or not
these two species anywhere occur together. The bacula in the two
species differ to the same degree as those of _E. quadrivittatus_ and
_E. umbrinus_. The differences between _E. u. fremonti_ and _E. r.
ruficaudus_ are such that in my opinion, _E. ruficaudus_ is a distinct
species.

_Specimens examined._--Total number, 58.

=Montana=: _Park Co._: Beartooth Mountains, 2 BS.

=Idaho=: _Bonneville Co._: Big Hole Mountains, 9,000 ft.,
near Irwin, 1 BS.

=Wyoming=: _Yellowstone Park_, 2. Park Co.: 16-1/4 mi. N and
17 mi.