TYPICAL BATS. 21 



Inhabiting caves and buildings in the daytime, this species 

 is so similar in its mode of life to the last, that scarcely any 

 observations on this point are necessary. It is, however, 

 stated to fly stronger and at a higher elevation, and not to be 

 so partial to the neighbourhood of trees. 



THE TYPICAL BATS. FAMILY VESPERTILIONID^. 



The members of this, the largest family in the whole Order, 

 are readily distinguished from the Rhijiolophidce by the absence 

 of a leaf-like expansion on the nose, and by the presence of 

 an earlet or tragus in the ear. These characters suffice, there- 

 fore, to distinguish them from the other British Bats, and 

 likewise to differentiate them from the allied family of the 

 Nycteridce, in which both the appendages in question are 

 present. Since they fail, however, to distinguish them from the 

 other two families of insect-eating Bats, we have to add certain 

 other characteristics. These are that the tail is either contained 

 completely within the membrane connecting the hind legs, or 

 is produced but a very short distance beyond its free margin ; 

 while, when the wings are folded and at rest, the first joint of 

 the third or middle finger is extended in the Hiie of the arm, 

 instead of being folded back upon its metacarpal bone. 



All these Bats have comparatively long tails, and minute 

 bead-like eyes, while their ears take origin from the sides of 

 the head, and not from the forehead. Although there are 

 always three pairs of lower incisor teeth, in the upper jaw 

 there may be either one or two pairs of these teeth, which are 

 in either case widely separated from one another in the middle 

 line. As regards the pre-molars, the number of pairs of these 

 teeth in the upper jaw varies from one to three, the anterior 

 ones being always small, and in some instances situated in- 

 ternally to the general line of the teeth ; in the lower jaw there 

 may be either two or three pairs of these teeth. 



