HOWELL — SEVEN NEW CHIPMUNKS 
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part of the range of Eutamias cinereicollis and so closely resembles that species 
in color that it has until recently escaped recognition. The sides are slightly 
paler and the nose less heavily washed with clay color than in cinereicollis, but 
in all other markings the resemblance between the two species is remarkable. 
However, arizonensis is decidedly smaller, with much shorter ears and hind feet, 
while the skull closely resembles that of atristriatus, and is widely different in 
size and proportions from that of cinereicollis. 
Eutamias amoenus vallicola subsp. nov. 
Type. — No. 168,027, U. S. National Museum (Biological Survey collection); 
female adult, skin and skull; from Bass Creek, near Stevensville, Montana 
(altitude 3,725 feet); collected March 23, 1910, by Clarence Birdseye; original 
number 1052. 
Suhspecific characters. — Similar to Eutamias amoenus luteiventris, but averaging 
paler throughout, especially the head, upper parts of body, and under surface 
of tail. 
Measurements of type. — -Total length, 223; tail vertebrse, 102; hind foot, 32.5; 
ear from notch, 14. Skull: Greatest length, 33.6; zygomatic breadth, 18.8; mas- 
toidal breadth, 15; interorbital breadth, 7.5; length of nasals, 11.3. 
Remarks. — This subspecies is apparently confined to the Bitterroot Valley 
and the adjacent foothills, but the exact limits of its range are not known. 
Twenty-six specimens from the valley, representing both winter and summer 
pelage, have been examined. 
Eutamias ruficaudus simulans subsp. nov. 
28487 
Type.-no. 4 - 3 ^ 
, U. S. National Museum (Biological Survey collection); 
female adult, skin and skull; from Coeur d’Alene, Idaho; collected June 1, 1891, 
by Clark P. Streator; original number 881. 
Suhspecific characters. — -Similar to Eutamias ruficaudus ruficaudus, but color 
of sides, under surface of tail, and tail edgings paler; skull with relatively broad 
braincase and rostrum. 
Measurements of type. — -Total length, 248; tail vertebrae, 117; hind foot, 33; 
ear from notch, 14. Skull; Greatest length, 35; zygomatic breadth, 19.3; mas- 
toidal breadth, 15.8; interorbital breadth, 7.8; length of nasals, 12.1. 
Remarks. — This race of the rufous-tailed chipmunk occupies the mountains of 
northwestern Montana (west of the main divide), northern Idaho, northeastern 
Washington, and southeastern British Columbia. It bears a rather striking 
resemblance to Eutamias amoenus felix of the coast region of British Columbia, 
but may be distinguished from that species by its slightly larger skull, longer and 
slightly paler tail, whiter underparts, paler sides of body and face, and more 
tawny head. 
Eutamias bulleri solivagus subsp. nov. 
Type. — No. 116,882, U. S. National Museum (Biological Survey collection); 
female adult, skin and skull; from Sierra Guadalupe, Coahuila, Mexico; col- 
lected May 1, 1902, by E. W. Nelson and E. A. Goldman; original number 15,169. 
