No squirrel was seen in December, January, and February, indicating that all were below ground in winter. _Specimen examined._--San Bernardino County: Desert Springs, 4000 ft., 1 (PC). =Ammospermophilus leucurus leucurus= (Merriam) Antelope Ground Squirrel Antelope ground squirrels were common in the Joshua tree woodland where they were noted up to 4500 feet elevation in Graham Canyon. None was found on the pinyon slopes, possibly because of the competition offered there by _Eutamias merriami_, or because the rocky nature of the soil there rendered burrowing difficult. Although observed less often in winter than in summer, this species is active all year. On February 6, 1949, in Mescal Wash, an antelope ground squirrel was foraging over the snow which was at least six inches deep. These squirrels were attracted to the carcasses of rodents used as bait for carnivore sets, and caused a good deal of trouble by disturbing the traps. Antelope ground squirrels used the topmost twigs of box-thorn bushes extensively as lookout posts, and many of their burrows were at the bases of these thorny bushes. This habit of regularly using observation posts is well developed in each species of ground squirrel found in the San Gabriels. _Specimens examined._--Los Angeles County: 6 mi. E and 1 mi. S Llano, 3500 ft., 2. =Eutamias speciosus speciosus= (Merriam) Lodgepole Chipmunk This chipmunk was characteristic of the most boreal parts of the San Gabriel Mountains. It was recorded from 6800 feet elevation at Big Pines, to an altitude of approximately 9800 feet near Mt. San Antonio, and was common where coniferous timber was interspersed with snowbrush chaparral. In upper Icehouse Canyon and near Telegraph Peak these chipmunks were associated with lodgepole pines and chinquapin, and one mile east of Mt. San Antonio individuals were often observed in thickets of manzanita. This chipmunk usually shunned pure stands of coniferous timber except as temporary forage ground. On Blue Ridge these chipmunks used the uppermost stems of snowbrush as vantage points, and when disturbed ran nimbly over thorny surfaces of the brush in seeking refuge in the tangled growth. In early November of 1951, these animals were not yet in hibernation on Blue Ridge. They were noted on November 6, after the season's first snows had melted; on November 13, however, a cold wind with drifting fog kept most of them under cover, and only two were noted in the course of the day. _Specimen examined._--Los Angeles County: 1 mi. S and 2 mi. E Big Pines, 8100 ft., 1. =Eutamias merriami merriami= (J. A. Allen) Merriam Chipmunk