214 ANIMAL LIFE IN THE YOSEMITE 



camp food supply were offered. Oatmeal was taken by preference, then 

 bread crusts. Dried prunes, put in at the same time, were not touched 

 until later. Once during the day one of the squirrels washed its face by 

 licking its forepaws and then rubbing them over its face. 



At Porcupine Flat a red fir stub was found to be inhabited by Flying 

 Squirrels. Two of the animals were trapped there and evidence of a third 

 obtained, after which the trunk was cut down and examined. The stub 

 was about 40 feet high and 5 feet in diameter, hollow at the base, and 

 well rotted interiorly. Inside, just beneath the bark, at a height of 10 feet 

 above the level of the ground, was a nest which was at least one year old. 

 It was composed chiefly of shredded bark. In a cavity in the center of the 

 tree, at the same level, was a new nest, evidently incomplete. This was 

 made of twig ends from the red fir, rolled into a spherical mass about 

 5I/2 inches (140 mm.) in diameter. The twigs used were % inch or less 

 in diameter and from 1 to 4 inches in length. They had been cut off neatly 

 from the extreme ends of the smaller branches of the fir, and green needles 

 were still adhering to the twigs. There was as yet no internal cavity in 

 this nest. Below the newer nest was a large mass of fir twigs. Various 

 cavities in the stump below the two nests contained droppings, suggesting 

 extended occupancy. Lumbermen near Chinquapin told of cutting down 

 a tree in which a nest containing two young was found. 



A pure albino Flying Squirrel, with pink eyes and pink claws, was 

 found in Yosemite Valley in August, 1918. It had been drowned in a 

 water bucket in Camp 17. This specimen was mounted and on exhibition 

 in the Superintendent's Office in 1919. 



The young of the Flying Squirrel are produced during the summer 

 season. The broods are small, and evidently but one brood is reared each 

 season. Four females containing embryos were collected, as follows: June 

 11, Merced Grove Big Trees, 2 small embryos; June 18, Mono Meadow, 

 4 embryos; June 29, Porcupine Flat, two specimens, one with 2 small 

 embryos, the other with 4 large embryos. A young individual, scarcely 

 half-grown, was taken in Yosemite Valley on July 13. A quarter-grown 

 youngster, which fell out of its nest in a black oak, was obtained in the 

 Valley on September 16 ; this represented an exceptionally late brood. 

 Two individuals, obtained at Aspen Valley on October 17 and at Sweet- 

 water Creek on October 31, were about half-grown. All these young 

 animals were well furred and all, including the smallest one, had obvious 

 'flight membranes.' 



The enemies of the Sierra Flying Squirrel are not known with certainty. 

 Several individuals which had come to grief in different ways were noted 

 by our party. In Yosemite Valley the dried remains of one was found 

 on the ground. On the Yosemite Falls trail, November 19, 1915, one was 



