THE GROUND SQUIRRELS OP CALIFORNIA. 



699 



which way the other has gone. Smell serves as a means of identifying 

 the other members of the same family. Outsiders are quickly detected 

 and promptly driven away. The members of one family of squirrels 

 which was closely watched were found to be very sociable, never quarrel- 

 ing among themselves. The parents were often seen sitting side by side 

 feeding in perfect harmony (see fig. 29), while at other times this pair 

 would sit together and rub noses in a very affectionate way. The only 

 time that they were seen to show fight was when a strange male squirrel 

 attempted to enter their burrow, and then the male of the pair promptly 

 put the intruder to flight. 



Fig. 29. Adult male and female Nelson Antelope Ground Squirrels, feeding in 

 uarmony side by side under wholly natural conditions. Photographed by J. Dixon, 

 May 9, 1918, on lower San Emigdio Creek, Kern County. The openings under the 

 horizontal layers of the wash banks afforded these squirrels safe retreats. Note the 

 characteristic Ammospermophilus pose of body and tail. 



The alarm note of the Nelson Antelope Ground Squirrel is much 

 subdued as compared with the clear penetrating trill of the Desert 

 Antelope Ground Squirrel. In fact, the former is much less frequently 

 heard at all. While the junior author was watching a family of Nelson 

 Squirrels at play on the morning of May 8, 1918, an old female was seen 

 to disappear into one of the numerous holes in the bank. About two 

 minutes later his attention was attracted by the low, inquisitive chirr 

 of this same squirrel, which was standing motionless less than ten feet 

 behind him. This alarm note was repeated five or six times at intervals 

 of from 30 to 45 seconds. In uttering this note the mouth was opened, 

 but the effort was not convulsive nor was the thorax greatly contracted. 

 The note was subdued in tone and probably not audible to human ears 

 at a distance exceeding one hundred feet. The confidential quality of 

 the call note reminded the observer very much of the clucking note of 

 the female valley quail when keeping her young together. 



107 



