320 Notes on a Collection of Mammals. [ZOE 
from trees, but it was particularly abundant in brush heaps, old 
lumber piles, and was common on fences. The two specimens 
taken on August 9 were caught in a cavity between a fence- 
board and post. They were male and female, adults, and in 
excellent breeding pelage. . 
7. Spermophilus chrysodetrus Merr. Gilded Chipmunk. 
Animals of this species seemed abundant above 6000 
feet on the west slope of the Sierra and at a lower altitude on the 
eastern slope. They were first seen on a rocky hillside near 
Cisco, a station on the Central Pacific Railroad below Summit 
Station. Afterwards they were found commonly at Summit 
Station, along=the Truckee River, on Mt. Tallac, and on a spur 
of the Sierra, skirting the east shore of Lake Tahoe and sloping 
down to the Carson Valley. They prefer open hillsides thinly 
grown with pines and most frequently make their burrows 
beneath rock piles and ledges. They seem to be entirely terrestrial. 
I did not see one on trees and bushes. They feed on various 
grasses and flower-seeds and probably also on the seeds of the 
fir and pine. 
Twenty specimens show a large amount of seasonal and 
individual variation. No one feature appears to be constant. 
The dorsal stripes vary in length, breadth, and intensity of color. 
In six specimens only can the white stripes be traced as far as 
the base of the tail; they also extend forward and blend into the 
golden yellow of the shoulders and post-auricular patches. In 
one specimen, No. 72, a female, the post-auricular patches are 
nearly white, and others show a complete gradation to the rich 
golden brown of the most highly colored specimens. The shoulders 
vary in color from a tawny iron-gray to the deepest orange. The 
color of the central area of the under side of the tail varies from 
pale orange to deep chestnut, and the tips of the fringing hairs 
from silvery gray to ochreous. A young specimen about two- 
thirds grown, taken August 6 on Mt. Tallac, is not so bright as 
the adults. In it a leaden gray suffuses the lower parts and 
extends well up on the sides, while the crown-patch, shoulders, 
and post-auricular regions are only softly tinged with ochreous. 
8. Spermophilus beldingi Merr. Belding’s Spermophile. 
This short-tailed spermophile is one of the most conspicuous 
