THE GROUND SQUIRRELS OP CALIFORNIA. 



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we properly (from a scientific standpoint), consider any animal 

 altogether apart from its normal surroundings. 



In the Inyo Mountains this squirrel was found by H. S. Swarth (MS) 

 to range from the level of the lowest pinons in Mazourka Canyon, about 

 7,500 feet altitude, to the highest summit visited by him, 10,500 feet. 

 In the White Mountains, east of Laws, the senior author found it to 

 range down Silver Canyon to as low as 7,000 feet altitude, and here 

 this and the Antelope Ground Squirrel of the lower country overlapped 

 in their ranges to a small degree. The "Callos," in such precipitous 

 canyons as Silver Canyon, were essentially "rock" squirrels, in that 

 they had their retreats in the slides of shale rock at the bases of the 

 cliffs and even in the broken rock outcrops far up the canyon walls. 

 Through and along these they clambered, a bit clumsily perhaps, but 

 without loss of foothold so far as was seen. 



Higher up, on the lofty rolling plateau forming the summit of this 

 mountain range, the Golden-mantled Ground Squirrels were extremely 

 abundant along the edges of the stunted forests of foxtail and lodgepole 

 pines, and even far from timber out on the sagebrush flats, but in the 

 latter locations there were always near at hand fractured granite out- 

 crops which afforded safe retreats. Where there were grassy meadows 

 the animals foraged all over them. It occurred to the observer that here 

 in the White Mountains there was but this one species of ground squir- 

 rel and that it therefore had the run of the whole place, as it were, 

 without meeting with any competitor, as is the case in the Sierras and 

 elsewhere. This would account for the facts as observed, namely, that 

 in the White Mountains the Copperheads were extraordinarily abundant 

 and ranged widely into all sorts of associations. 



Our lines of rat-traps baited with rolled oats brought in many 

 "Callos," even youngsters but a third grown, and it was practically 

 impossible to keep steel traps set during the day, as the bait, consisting 

 of the bodies of the various birds and small mammals prepared for 

 specimens, seemed to be especially attractive to the squirrels. Wherever 

 the traps were set, they would be searched out and unwittingly sprung 

 as the squirrels scrambled over them in quest of the bait. It seemed 

 impossible that the "Callos" could have located some of the settings 

 except through scent, and it is reasonable to suppose that the sense of 

 smell is employed not only in seeking meat but when searching for the 

 bulbs of certain plants. 



Young were out in numbers the last week of July at the 10,000-foot 

 level, being then one-third to one-half grown. Lower down, in Black 

 Canyon at 8,000 feet altitude, half-grown young were seen on July 5 

 (1917) ; and at 10,500 feet altitude, on Cottonwood Creek, third-grown 

 young were noted on August 8. This shows the usual variation of 

 appearance of young with altitude, which of course has to do with 

 advance of the season, and so with temperature. 



In Mazourka Canyon, Inyo Mountains, two females, each containing 

 six embryos, medium-sized and small, respectively, were taken May 19 

 and 22 (1912). We found no evidence of litters of a larger number 

 than six; and there is certainly no more than one litter per year. 



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