BATS 59 



end of July the days had shortened so that Eptesicus was abroad at 7 :30. 

 In late August, at Merced Lake, it was out at 7 :15 p.m. ; and on October 2 

 that same year, in Yosemite Valley, a bat of this species was seen over 

 Sentinel Meadow at 5 :46 p.m., when Half Dome was still pink-tinged with 

 direct sunlight. 



When foraging, this bat courses about in clear places in the forest or 

 over open caiions; usually it keeps well up, anywhere from 25 to 50 feet 

 above the ground. Each individual seems to have a definite forage route 

 or beat. If the collector misses a shot, he is sure to have another chance 

 at the same bat if he but holds his post until the animal swings around over 

 its course again. The flight is relatively slow, and its course is maintained 

 in a direct line for longer periods than is that of most other bats. These 

 features, together with its larger size, render the Large Brown Bat an 

 easier target for both the eye and the gun than are most other species. 



The electric lights in the 'streets' of Yosemite 's tent cities serve to 

 attract multitudes of native moths and other night-flying insects and these 

 in turn draw the bats. One evening in July there were fully 20, mostly 

 of the present species, to be seen about the lights in one of the camps, 

 where they seemed to be faring exceedingly well. 



Our records for this bat, based upon specimens taken, end with 

 August 28 (1915) at Merced Lake; but bats believed to be of this species 

 were seen until late in October. No Large Brown Bats have been observed 

 in the region during the winter months. The species seems not to have 

 been found anywhere in California during that season; in all probability, 

 like many of the birds, it retires to some more southerly locality to spend 

 the period when flying insects are scarce or wanting in our latitudes. 



Hoary Bat. Nycteris cinerea (Peale and Beauvois) 



Field characters. — Largest bat in the Yosemite region, slighly larger than either 

 Large Brown Bat or Pallid Bat. Total length 51/2 inches (135 mm.), tail 21/2 inches 

 (60 mm.), hind foot % inch (11 mm.), ear 1/3 inch (9 mm.), stretch 151/2 inches 

 (398 mm.). Coloration 'hoary,' the hairs being brown at base and extensively tipped 

 with white; wing membranes blackish. Tail membrane furred like back. (See pi. 21a.) 



Occurrence. — Recorded definitely twice in Yosemite region; probably rather common. 

 Individual specimens taken at Snelling, April 15, 1916, and at Merced Lake, August 20, 

 1915. Inhabits wooded localities and finds daytime refuge in trees. Solitary. 



The Hoary Bat, one of the most distinctive of our Californian bats, is 

 included in the fauna of the Yosemite region on the basis of two specimens 

 captured. On several other occasions, however, individual bats which we 

 believed to be of this species were seen in flight. 



