MONO CHIPMUNK. Eutamias amoenus monoensis Grinnell and Storer

Field characters.—Size small (head and body about 4-1/2 inches, tail 3-1/4 inches long). (For comparative measurements see footnote 15, p. 177.) Usual chipmunk pattern of coloration; flanks light brown. (See pl. 3c). Distinguished from frater by smaller size, paler coloration generally, less conspicuous white markings, and yellowish rather than reddish color on bases of tall hairs; from alpinus and pictus by larger size, relatively longer tail and darker general tone of coloration. Voice: Similar to that of Tahoe Chipmunk.

Occurrence.—Moderately common in Canadian Zone on east base of Sierra Nevada; recorded on Mono Craters and from Leevining Creek south to Gem Lake and Silver Lake. Altitudes of capture, 7000 to 9100 feet. Lives largely within the belt of mountain mahogany, where it stays in brushy and rocky places.

The Mono Chipmunk in the Yosemite section is limited in its range to the east slope of the Sierras. It touches or overlaps the ranges of three other species of small chipmunks, and difficulty may therefore be experienced in identifying the animals in the field.

The Mono Chipmunk seems to be restricted to the arid Canadian Zone, and it there dwells chiefly within the belt of mountain mahogany. While typically a ground dweller, like the Allen Chipmunk of the west slope, it does sometimes ascend the smaller trees up to a height of 6 or 8 feet. It perches commonly on the tops of boulders where it obtains an unobstructed view over the tops of the bushes roundabout.

In September, 1915, around Williams Butte, the Mono Chipmunks were busily engaged in harvesting seed crops of one sort or another. At Gem Lake they ranged down from the nearby brush and rocks to the border of a meadow and were seen under the willows there pulling down the grass heads and gathering the ripening seeds. Elsewhere they ranged out under the sagebushes, sharing this sort of cover with the Sagebrush Chipmunk.