134 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ho 



nocturnal and not crepuscular, beginning to forage 30 to 40 minutes 

 after sunset. Then it moves in such a delicate, mothlike fashion in 

 and out of foliage that it is not easily detected. It has been suggested 

 that to see this species the observer should station hunself at dusk 

 under a tree whose foliage is not too dense to be seen through (e.g., an 

 ash) and watch closely for the bats to appear among the branches 

 overhead. Close attention is necessary, for the movements of the 

 long-ear may be so stealthy that the presence of even five or six 

 individuals hunting simultaneously in a single tree may be overlooked. 

 Furthermore, the observer should choose fine weather for his vigil 

 inasmuch as P. auritus seems to be much affected by atmospheric 

 conditions. 



Undoubtedly this species catches some flying insects, but much of 

 its prey is picked from foliage. It hovers somewhat like a humming- 

 bird to pick insects from leaves or flowers, or it plunges into the middle 

 of a spray and remains for several seconds clinging to the twigs. It 

 has been observed climbing among branches, on tree trunks, and on 

 walls, presumably in search of food. 



Flight from tree to tree or roost takes a special form. When the 

 destination is near at hand the bat darts through the air with a swift, 

 direct flight. When the destination is more distant, the bat makes a 

 plunging descent to within a few inches of the ground and makes off 

 in a jerking zig-zag fashion. So sudden and irregular are its move- 

 ments that its course is difhcult to follow. 



In direct flight the ears appear to be held erect, but when the bat 

 threads its way among foliage in search of insects they are thrown 

 forward so as to resemble a "proboscis" or are curled downward and 

 forward so as to suggest "cheek pouches." In sleep the ears are 

 bent backwards until they lie close along the body, partially covered 

 by the wings, or they are curled down and forward almost like the 

 horns of a ram. In the former position the tragus always points 

 forward, in the latter it may be reflexed. The ears may be folded or 

 unfm-led slowly, or snapped up suddenly. The action of the two ears 

 can be synchronized or independent. 



P. auritus alights in an upright position, clinging first to an object 

 with its thumbs. It soon reverses its position and hangs head down- 

 ward. In climbing or walking, the limbs are moved alternately, the 

 head bobs to and fro, and the bat advances in a curious jerky fashion 

 but with surprising speed. Preparing to fly, the bat raises its head, 

 pricks forward its ears, and looks about with a seemingly intelligent 

 air. Wlien forced to do so, P. auritus swims rather well. 



The long-ear has a variety of call notes. The commonest are a 

 high-pitched chirping squeak used in ordinary communication and in 



