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ANIMAL LIFE IN THE YOSEMITE 



numerous small, elongated black droppings of this species. These natural 

 avenues of travel are used also by other small mammals such as white- 

 footed mice and chipmunks. One of these meadow mice was captured in 

 a trap set on top of a heap of dead branches of aspen, about 2i/2 feet above 

 the ground. Foraging is carried on down close to the water's edge, as 

 many individuals were trapped close beside streams; and occasionally one 

 is seen swimming in the water. 



Fig. 21. Willow and grass covered seepage slope in head of Lyell Caiion; altitude 

 about 10,000 feet, Hudsonian Zone. Habitat of the Sierra Mountain Beaver or Aplo- 

 dontia. In the willow thickets were Hudsonian White-crowned Sparrows. The grassy 

 banks contained burrows and runways of the Yosemite Meadow Mouse. Photograph 

 taken July 24, 1915. 



This mouse is more restricted than its path-traveling relatives to night- 

 time foraging. Being a free-ranging animal it might be subject to capture 

 by day-prowling, carnivorous birds or mammals in the same way as is 

 Peromyscus. For that reason, probably, it is abroad but little during the 

 day. Only on one occasion did we see an individual of this species alive. 

 In Glen Aulin at about 9 :30 a.m. on October 1, 1915, one was seen scamper- 

 ing over the leaf mold on the floor of a lodgepole pine forest. 



The breeding season of this mouse, as revealed by our trapping records, 

 embraces most of the summer season ; we are unable to give its exact limits. 

 A quarter-grown youngster collected at Merced Grove Big Trees on June 13 



