MAMMALS OF THE MEXICAN BOUNDARY. 291 



copper mines of the Mimbres, near Foi-t Webster, New Mexico. Mr. 

 H. W. Henshaw has taken it at El More and Dr. J. E. McKee at 

 Fort Defiance in this Territory. To the north of the Colorado 

 River, Dr. C. Hart Merriam obtained it at Ogden, Utah, in 1872, 

 thus greatly extending its known range; and its future occurrence 

 in the area lying between that point and the Arizona border may 

 be safely predicted. 



This preeminently saxicolous mammal is common in the limestone 

 bluff's and canyons bordering the Verde River in the vicinity of the 

 military post of Fort Verde; but I never detected it, during a resi- 

 dence of more than four years, in the broad river bottom. In fact, 

 it avoids level ground, always seeking cliffs and the rockiest places. 



It infests the bluff banks and side canyons of Beaver Creek, which 

 springs from numerous sources in the Mogollon Mountains of central 

 Arizona and empties into the- Rio Verde at Fort Verde. This was 

 the most convenient place in which to study the habits of this nimble 

 climber, whose fleetness and boldness, displayed in scaling the per- 

 pendicular cliffs (the crevices and holes of which afford it sufficient 

 shelter), never ceased to excite my admiration and astonishment; but 

 its excessive shyness precluded a close acquaintance. It was next to 

 impossible to kill one; and the few specimens taken were the result 

 of snap shots, usually from the saddle, when both the squirrel and 

 myself were in motion, or of tedious lying-in-wait. It runs with 

 extraordinary' swiftness, quickly placing a wall of rock between 

 itself and an enemy, or disappearing into a crevice. It lacks the 

 curiosity of the eastern chipmunk, and seldom ventures to exhibit 

 itself after being frightened to cover. 



It delights in the picturesque caves and ruined buildings of the 

 cliff' dwellers, in which these canyons abound. From the shelter and 

 concealment of these ancient habitations I have been able to watch 

 the actions of this chipmunk, whose timidity contrasts strikingly 

 with the confiding familiarity of the Arizona chipmunk. When all 

 is quiet and it fancies itself unobserved, one emerges from a hori- 

 zontal fissure in the wall of soft limestone and utters a resounding 

 note, followed by a chirrup and rattle, as another little fellow comes 

 out close behind it. Then they make a rush along some previously- 

 invisible ledge and disappear in a vertical seam, before unnoticed, as 

 if by magic. Thence issue excited chipperings, followed by the 

 scratching of cla'ws upon the rock face overhead, and they are gone. 

 Another family presently appears in another quarter, where they 

 frolic noisily and nervously brandish the long, bushy tail, which is 

 the crowning glory of this pretty species, figuratively speaking, for 

 they drag and whirl it after them as they scuttle like lizards over the 

 cliff. Again the pattering of paws and dropping of loose scales of 

 limestone from above announce the return of the first pair. They 



