An old female trapped on March 18,1951, in San Antonio Canyon, had three embryos each about 105 mm. long from rump to crown, and weighed 9.2 lbs. The average weight of four non-pregnant females was 6.8 lbs., whereas the average of six males was 7.5 lbs. _Specimens examined._--Total, 11, distributed as follows: Los Angeles County: Mescal Canyon, 4800 ft., 1; 4 mi. E Valyermo, 5200 ft., 2; Cow Canyon, 4500 ft., 2; San Antonio Canyon, 3000 ft., 1; Thompson Canyon, 2500 ft., 2 (PC); 1/2 mi. W Palmer Canyon, 2000 ft., 3 (PC). Family FELIDAE =Lynx rufus californicus= Mearns Wildcat Wildcats range over the whole of the San Gabriel Range, with the possible exception of the tops of the highest peaks such as Mt. San Antonio and Mt. Baden Powell. Sign of these animals has been observed, or specimens have been taken, from the coastal sage belt up to about 8500 feet in the yellow pine forests on Blue Ridge. The subspecies _baileyi_ occurs on the desert slope of the range. Wildcats are most common in the chaparral belt where they forage widely from the ridges down into the canyons. Judging from trapping records bobcats are not so common here as the gray fox. Bobcats occur in the sage belt, where they are most common in the broken country around washes and in brushy areas. Although bobcats and coyotes occupy the same general areas here, the habitat preferences of these animals seem to be different, with coyotes occupying the more open country. An indication of the hunting habits of bobcats is furnished by the occurrence of masses of prickly-pear thorns beneath the skin of the legs, particularly the forelegs, of three specimens trapped in the sage belt. These thorns probably were acquired while the bobcats foraged for woodrats or cottontails in the patches of prickly-pear, which are locally abundant in the sage belt. On March 12, 1951, a small subadult female bobcat, trapped at 4000 feet in San Antonio Canyon, was found dead in the trap and had numerous deep cuts around its head and shoulders, and severe bruises on the right shoulder. The spacing of the cuts, and the tracks around the set, indicated that while held in the trap this animal had fought with a second bobcat that had inflicted the fatal wounds. It seems unlikely that the fight was caused by a male attempting to copulate with the female held in the trap, for the female was found to be carrying an embryo. In Live Oak Canyon, in December, 1950, tracks and bits of fur indicated that a bobcat had killed and eaten a gray squirrel. Remains of cottontails were found in the stomachs of two bobcats. All six bobcats from the Pacific slope had nematode worms in the pyloric end of the stomach. Two females obtained on March 12 and 19, 1951, each had one embryo approximately one inch long (rump to crown). The following list gives the weight of each of the specimens from the Pacific slope of the San Gabriels.