326 University of California Publications in Zoology [Vol. 10 



Ammospermophilus leucurus leucurus (C. H. Merriam) 

 Antelope Chipmunk 



An abundant species along the lower desert slopes of the 

 San Jacintos. Beginning at the southeast, the species was first 

 encountered on Piiion Flat well up into the piiion belt. It was 

 here observed as high as Asbestos Spring. 4500 feet. From there 

 northeast all over the Dos Palmos and Black Mountain country 

 it was plentiful, as also down Palm Canon from about the 3000- 

 foot contour to its mouth. Numerous at Palm Springs, Snow 

 Creek, and as far up San Gorgonio Pass as Cabezon, 1700 feet. 

 Nothing was seen of this rodent at Whitewater, where Citellus 

 I. chlorus was common. Apparently the antelope chipmunk 

 does not far invade the open sandy stretches of desert, which 

 are complementarity occupied by C. t. chlorus. 



An interesting discovery was the existence of A. I. leucurus 

 as a colony, probably now isolated, in San Jacinto Valley. Here. 



around Vallevista, they upied a wash well out from the mouth 



of a canon entering the valley from the east. 



Specimens of this chipmunk were taken as follows: Dos 

 Palmos and Carrizo Creek. 3000 to 3500 feet, five (nos. 1933- 

 1937) ; Palm Canon, 3000 feet, one (no. 2058) ; Palm Springs, 

 450 feet, five (nos. 6043-6045, 6393,, 6757) ; Snow Creek, 1500 

 feet, five (nos. 1508-1512) ; Cabezon. 1700 feet, seven (nos. 1308- 

 1314) ; Vallevista. 1800 feet, four (nos. 2268-2271). 



The specimens from Vallevista do not present appreciable 

 differences from those from the desert base of the mountains. 

 Although typically a member of the arid Lower Sonoran fauna, 

 this rodent in places ranges higher than most other Lower Son- 

 oran forms, even well through the Upper Sonoron, as on the 

 north side of the San Bernardino Mountains (see Grinnell, 1908, 

 p. 141). It is not difficult, therefore, to explain its occurrence 

 in San Jacinto Valley by one-time invasion during a period of 

 meteorologically favorable seasons over the intervening Upper 

 Sonoran hills from the vicinity of Cabezon. 



Both at Cabezon and Vallevista this chipmunk was observed 

 in cactus plants, eating buds or fruits. The animals appeared 

 to be well able to move about and handle the prickly fruits 

 without incurring injury. In one ease, however, a stout thorn 



