Page:Natural History of the Ground Squirrels of California.djvu/117

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THE GROUND SQUIRRELS OF CALIFORNIA.
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farmers and orchardists reported that little or no damage was done by this rodent, although the big Fisher Ground Squirrel was a decided pest there. The little Antelope "Chipmunks" seemed to keep closely to the wild land, feeding upon the native seeds and fruits, especially those of the cactuses.

Still, locally, they may prove noticeably destructive. This was the case in an almond orchard near Fairmont in northern Los Angeles County, where in June, 1904, the present authors saw the animals climbing the trees in the outer rows next to the wild land and carrying down the as yet unripe almonds. These and the Fisher Ground Squirrels were both complained of bitterly by the owner. Again, in Owens Valley near Independence, on May 7, 1912, a male Antelope Ground Squirrel was captured, with its cheek-pouches filled with wheat. The nearest grain field was a quarter of a mile distant. It is thus quite to be expected that where cultivated land adjoins wild land this species will make raids upon such crops as prove to its liking.


NELSON ANTELOPE GROUND SQUIRREL.

Ammospermophilus nelsoni nelsoni (Merriam).


Other names.—Nelson Spermophile; Nelson Ground Squirrel; Antelope Chipmunk, part; Spermophilus nelsoni; Citellus nelsoni.

Field characters.—A small yellowish-brown ground squirrel with one narrow white stripe on each side of body, and with a short flat tail nearly always held curled up over the rump so as to show the creamy white under side. Length of body alone about 6¼ inches, tail about 2⅘ inches more.

Description.—Adult in summer pelage: General color of upper surface from nose to base of tail light clay color, brightening toward pinkish cinnamon on shoulders, flanks, and outer sides of fore and hind limbs; a narrow white stripe on each side of body from shoulder to side of rump. Eyelids, ears and sides of head dull buffy white; whiskers black. Whole lower surface of body white, the hairs white to bases; soles of feet densely white-haired forward to tubercles, thence to balls of toes naked; upper surfaces of feet white, buff tinged; claws blackish brown with pale horn-colored tips. Tail as in leucurus, but upper side near base clay color; under surface creamy or buffy white centrally. Adult in winter pelage: Coat softer, the hairs being longer and more silky than in summer. General coloration as in summer, but tone of upper surface a little darker, and with a fine grizzling due to more variegated color pattern on the individual hairs. White hairs of lower surface with extreme bases lead-color.

Color variations.—-Sexes alike, as far as we can see. Young colored as in the summer adults, but pelage finer in texture.

Measurements.—Average and extreme measurements, in millimeters, of twenty full-grown specimens from the vicinity of Bakersfield, Kern County, are as follows: Ten males: total length, 226 (210–242); tail vertebræ, 70 (61-76); hind foot, 38.6 (36–40); ear from crown, 5.3 (5–6); greatest length of skull, 39.9 (39.0–41.6); zygomatic breadth, 23.2 (21.4–25.0); interorbital width, 9.9 (9.5–10.4). Ten females: total length, 221 (203–238); tail vertebræ, 68 (64–74); hind foot, 38.4 (35.0–41.0); ear from crown, 5.7 (5.0–6.0); greatest length of skull, 39.4 (37.8–41.3); zygomatic breadth, 22.6 (21.5–24.4); interorbital width, 9.7 (9.0–10.6).

Males will be seen from the above figures to average slightly larger than females. The decidedly greater size of nelsoni as compared with leucurus is at once apparent.

Weights.—Three adult females were found to weigh 141.8, 142.6, and 179.0 grams, respectively; average, 154.5 grams, or 5½ ounces. In bulk nelsoni is thus about 50 per cent larger than leucurus.

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