304 BULLETIN nil, UNITED STATES NATIONAL MUSEUM. 



In general terms, it may be said that it inhabits the whole Territory, 

 except such limited areas as are too high and cold, and the southeast 

 corner of Arizona. I have personally observed it throughout the 

 length and breadth of Arizona. Some localities are interesting, 

 however, as showing its proclivity for following up the canyons and 

 water courses as far as possible, into regions elsewhere uninhabitable. 

 Thus it was found in abundance in the dee]) canyon of the Colorado, 

 although unable to withstand tin 1 rigors of the climate on the summit 

 of the high bluffs bordering that stream; thence it penetrates the side 

 canyons as far as possible, and was observed in the tributary canyon 

 of Cataract Creek. It naturally reaches the highest elevation where 

 there is a continuous slope from the low country with a very gradual 

 alteration of the conditions. We found it in the cedar woods about 

 Peach Springs, and along the Atlantic and Pacific Railroad as far as 

 Aubrey Station (altitude 5,151 feet), living in large colonies in piles 

 of loose rocks from railway cuttings. They were running actively 

 about, notwithstanding the preceding night had been intensely cold, 

 ice having frozen to the depth of 2^ inches in our camp kettle. The 

 coats of several specimens from there were much denser and softer 

 than any from the Verde Valley, taken at the same season. 



In the valley of the Agua Fria, a tributary of the Gila, this species 

 was found at the stage stations of Bumble Bee and Antelope, at a con- 

 siderable altitude. 



This ground-squirrel is abundant in the Verde Valley, where it 

 derives its subsistence mainly from the dwarf form of mesquite grow- 

 ing there, beneath which wind the intricacies of its complicated bur- 

 rows. It shares the terrestrial habits of the Say ground-squirrel; 

 but there are few of the Sciundae that can not climb when tempting 

 food is seen dangling overhead, and the golden bunches of ripe mesquite 

 beans are sufficiently tempting to stimulate the present species to 

 arboreal enterprise; and it may be seen awkwardly hugging the spiny 

 branches or sunning itself on the limbs, with tail dropped, frequently 

 uttering its hollow call-note. It lays up ample stores of mesquite 

 seeds in its burrow, which doubtless accounts for its somewhat rare 

 appearance above ground during the coldest weather. It has sufficient 

 intelligence to husk the seeds from their long pods before carrying 

 them under ground. The capacity of its cheek-pouches is considera- 

 ble. Those of one that I shot contained 44 mesquite beans, in bulk 

 just a thimbleful. Its mercurial temperament savors of the spiciness 

 of its food. It is much heavier and stouter than the Gila or Rocky 

 Mountain chipmunks, and is brimful of playfulness and noisy activity, 

 delighting in the fierce power of the summer sun. As one rides over 

 the mesquite fiats, it scurries from underfoot, carrying its tail straight 

 up in the air, uttering explosive chipperings as it hurries to the near- 

 est mesquite bush, under whose shade it is quite certain of finding 



