THE VAMPIRE-BATS 301 



back beneath, instead of above, its supporting metacarpal bone. Moreover, while 

 the greater part of the wing membranes is very thin, the portion along the sides 

 of the body and the lower moieties of the limbs is much thickened ; beneath this 

 thickened portion the remaining parts of the wings lie folded away as if in a case ; 

 and in this condition this species is better adapted for a crawling or climbing life 

 than any other member of the order. There are other peculiarities adapted to aid 

 in climbing, connected with the thumb, feet, and legs. The length of the head and 

 body is two and one-half inches ; and the general color of the upper parts is brown, 

 though beneath they are paler. Even the fur of this bat can, under the micro- 

 scope, be at once distinguished from that of all other species ; the individual hairs 

 being very thick, and with only faint traces of the projecting scales characteristic of 

 other bats. The tail is extremely short. From its structural peculiarities Dr. Dob- 

 son is led to believe that this curious bat hunts for its insect food, not only in 

 the air, but also on the branches and leaves of trees, among which it would certainly 

 be able to creep with ease. 



THE) VAMPIRE-BATS 



Family PHTLLOSTOMATID^ 



The extensive group which it is convenient to allude to collectively under the 

 name of vampires, is exclusively confined to Central and South America and the 

 West Indian islands. While related to the preceding family, with which they agree 

 in the characteristics mentioned on p. 291, they differ in certain other points of im- 

 portance. And they appear to have a relationship to the smooth-nosed free-tailed 

 bats {Emballonurida;} similar to that presented by the leaf -nosed bats {Rhinolophidce} 

 to the typical bats ( Vespertilionidfe) . 



They are characterized by the presence of three bony joints in the third or mid- 

 dle finger of the wing, accompanied either by a well-developed nose-leaf, or by folds 

 of skin and warts on the chin. Such of them as have a nose-leaf (and these are 

 by far the greater majority) may be always distinguished from the leaf -nosed and 

 horseshoe-bats, not only by the number of joints in the third finger, and by the 

 characteristics mentioned on p. 291, but likewise by the presence of a distinct tragus 

 to the moderate- sized ears. Moreover, if we examine the dried skulls of any mem- 

 bers of the two families, we shall find that while in the leaf-nosed bats and their 

 allies the premaxillary bones, in which the one pair of small upper incisor teeth are 

 implanted, are small, separate, and loosely attached to the skull, in the vampires 

 these bones are large, firmly united both to one another and the skull, and generally 

 carry two pairs of large incisor teeth. 



The number of genera and species of vampires is so great that only the more 

 remarkable types can be even mentioned in this work. With the exception of a few 

 species having well-developed tails and a large membrane between the hind legs, 

 which are of strictly insectivorous habits, the vampires are remarkable for the varied 

 nature of their food ; some subsisting on a mixed diet of insects and fruits, others 

 being wholly frugivorous, and a few exclusively bloodsuckers. Others again, 



