SENSORY ADAPTATIONS OF BATS. 145 



I have frequently found colonies clinging to the roof in places 

 where there were no large prominences and no crevices, and I 

 have seen flying bats secure a foothold in such places in the cave, 

 and also to smooth, but unplaned, lumber in a house. The top 

 and side walls are preferred equally by the different species of 

 Myotis, but Pipistvelhis is generally found on the side walls of the 

 higher chambers. The claws of both feet are hooked about 

 prominences on the stone and when the animal is resting on a 

 vertical wall, the wrist and the nails of the thumbs also rest 

 against the wall and form some support. However, the feet alone 

 are strong enough to support the animal for weeks at a time and 

 even to support several others of its kind when they cling to it. 



The social habit is strongly developed in M. liicifugns. The 

 large colonies seen by Blatchley in Wyandotte and Saltpeter 

 Caves were almost certainly of this .species, although he calls them 

 ]SI. subiilatus. I have never seen them hanging in clusters as 

 large as these but have frequently seen bunches of fifty or more. 

 The guides at the former of these caves tell me that bats gather 

 there in winter in clusters comparable only to a swarm of bees, 

 and probably equalling such a swarm in number of individuals. 

 Myotis siikdatiis and M. vclifer are not abundant in this region 

 but are generally found associated with groups of their abundant 

 congener. 



Corynorhinus macrotis has only been seen in dim light near the 

 entrances, and there it was found clinging to the side walls with 

 its long ears folded down along the sides of the neck. Eptesicns 

 fuscus has not been seen far within the caves nor is it abundant. 

 The largest number I have found in one place is six, taken near 

 the entrance of Mayfield's cave on December 21. 



Pipistrellus subflavns is solitary in habit. Occasionally two are 

 found side by side, though I have never seen them clinging to 

 each other except in mating. However, they do not avoid the 

 vicinity of others of their own kind nor other species. This species 

 seems to prefer the side walls of the higher passages. I have 

 never seen it suspended from the roof except where there was a 

 crevice or prominent ledge. 



