THE GROUND SQUIRRELS OP CALIFORNIA. 



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under side of the tail brilliantly white. This latter feature is in itself 

 unique, for it is accompanied by a most striking mannerism, that of the 

 almost constant carriage of the stubby, flat-haired tail in an upright 

 position, held against the back, so that the white under surface shows 

 as a white ' ' flag ' ' when the animal is scurrying away, much as with the 

 similarly advertising marks of the cottontail rabbit and antelope ; only 

 with the ground squirrel the effect in catching the eye of the observer 

 is still further heightened by the way in which it is spasmodically 

 twitched whether the animal be at rest or running. This flickering 

 beam of white ever holds the attention as long as the squirrel is below 

 the level of the horizon, and short of its burrow or the concealing tangle 

 of prickly vegetation which it is so anxious to put between it and its 

 pursuer. 



The race called appropriately Desert Antelope Ground Squirrel 

 (locally, Antelope "Chipmunk" because of its stripes, small size and 

 sprightly manners) occurs broadly over the Colorado and Mohave 

 deserts, thence north clear through the Inyo region. It shows rather 

 wide adaptability to the varying conditions in this vast area, more so 

 than any other desert ground squirrel, and ranges from below sea level, 

 as on the floor of Death Valley, np regularly to 6,500 feet on the steep 

 slopes of the desert mountains. It even ' ' spills over ' ' the confining rim 

 of the Mohave Desert to the westward, locally, on to the Pacific drainage, 

 as shown in detail in the accompanying list of specimens and on the 

 map (fig. 24). Although notably continuous in its range over great 

 stretches of country, it is not difficult to discover preferences, as indicated 

 by relative abundance. Level sandy ground is, as a rule, but sparsely 

 inhabited ; and we know of some stretches of desert, such as the floor 

 of the Coachella Valley northwest of Salton Sea, where none at all 

 seem to exist, although the species is abundant in the foothills adjacent. 

 The kind of ground most generally preferred seems to be hard-surfaced, 

 gravelly wash-fans or hill slopes. Kinds of vegetation present seem to 

 be immaterial, though clumps of squaw tea, creasote bush, cactus, or 

 tree yucca characterize much of the territory where the Antelope 

 Squirrels are most abundant. 



Our mention of the above preferences must not give an erroneous 

 idea as to special nature of the habitat of this species. It may be said 

 again, for emphasis, that this animal thrives in a great variety of 

 situations. We have seen it on the mesquite-crowned sand dunes of 

 Death Valley, there as a companion of the Death Valley Round-tailed 

 Ground Squirrel; on the sagebrush covered flats at the extreme head 

 of Owens Valley, in the metropolis of the Stephens Soft-haired Ground 

 Squirrel; on the creasote hillsides near Little Lake, one of our very 

 few record stations for the Mohave Ground Squirrel ; among the pinons 

 and granite boulders of the northern section of the Panamint Moun- 

 tains, then associated with the big Fisher Ground Squirrel; and even 

 upon the steep rocky slopes of the White Mountains at 7,800 feet alti- 

 tude, in the same rock slides with the Inyo Golden-mantled Ground 

 Squirrel! Truly a cosmopolite is the Antelope Ground Squirrel, just 

 so far as the dry atmosphere of the desert extends ; but the coastal fog 

 and general humidity of the Pacific drainage are almost strictly taboo. 



The burrow of this rodent is in nearly all cases situated at the side 

 of a dense brush-clump or boulder so that protection is afforded from 



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