132 



ANIMAL LIFE IS TUE YOSEMITE 



numerous small, elongated black droppings of this s])eeiess. 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 a-spen, about 2yo 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 Canon; altitude 

 about 10,000 feet, Iludsonian Zone. Habitat of the Siena Mountain Beaver or Aplo 

 dontia. In the willovv thickets were Hudsonian White-crowned Sparrows. The gra.><sy 

 banks contained burrows and runways of the Yoseniite 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 maniiuals in llie sanu» way as is 

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

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

 In Glen Aulin at about 9 :30 a.m. on October ], lOlf), one was seen scamper- 

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



The breeding season of this mouse, }us revealed by oui' trai)|)iiig 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 i:{ 



