MAMMALS OF THE MEXICAN BOUNDARY. 275 



forests of the highest altitude; the Abert squirrel is an inhabitant 

 of the pine belt, between 5.000 and 8,000 feet altitude; the Apache 

 squirrel is known only from the Chiricahua Mountains; while the 

 present species prefers the deciduous timber in the canyons and 

 along- the streams of the lower country, ranging upward into the 

 loAver pine zone about as high as does the Gila chipmunk {Eutamias 

 dor sails). 



AVliile in Arizona I came acros,s the following letter from Dr. 

 Elliott Coues to my friend Mr. "Willard Rice, which is of interest in 

 connection with the history of this squirrel. Doctor Coues kindly 



consented to its publication : 



1726 N Street NW., 

 Washington, D. C. December 2Ji, 188^. 

 Dear Friend Rice : I am glad to hear from you and thank you for the strange 

 squiri-el. which has a stranger history. Do you rememher shooting a s(inirrel 

 for me at Prescott in 18G5? Well, that was a speeies new to science, which I 

 named Sciitrus urizonensis, and puhlished in 1867. From that day to this I 

 never got another one like it, and I think only two or three specimens are known 

 to naturalists besides these two of yours. It is a pleasant memory — these two 

 specimens — bridging an interval of nearly twenty years. 

 Sincerely, your friend, 



Elliott Coues. 



Since discovered by Doctor Coues in 1865, the Arizona gray squir- 

 rel has not proved to be an abundant species, material for its critical 

 study having come to the hands of naturalists very slowly. Dr. 

 J. A. Allen, in the Monographs of Xorth America Rodentia (p. 738), 

 refers this species to Sciurus colliad Richardson, and notes the 

 acquisition of two additional specimens since the single one obtained 

 by Doctor Coues. These were collected in Arizona, by Mr. Ferdi- 

 nand Bischoff, in 1871. In my earlier collections, deposited in tiie 

 American Museum of Natural History, New York, were fourteen 

 specimens, taken in the months of March, April. July, and August. 

 Mr. E. W. Nelson writes me as follows : 



I have met Coues's Sciurus arlsoncnfth only once, when, in February, 1885, I 

 shot a specimen in the mountains just east of the headwaters of the San Fran- 

 cisco River in New [Mexico. A couple of weeks later in the same month a man 

 brought me a second from a trilnitary of the San Francisco about 10 miles 

 lielnw where mine was taken, and told me that it was about equally common 

 with the other gray squirrel (.s'. ahcrti.) 



The Arizona gray squirrel, in common with other squirrels, some- 

 times migrates from place to place in large numbers. ISIr. Stewart 

 Daniels, who obtained many specnnens of mammals and birds for 

 me in Arizona, resided for several years in the canyon of Fossil 

 Creek, 25 miles southeast of Fort Verde, without seeing one of these 

 squirrels, but during March and April, 1880, there was a sudden 

 influx of them, and numbers Avere seen daily. I am indebted to Mr. 

 Daniels for eight specimens, which he kindly sent me at the time. 



In the foothills below Squaw Peak, 4 miles southwest of Fort 



