262 ZOOLOGY. 



otherwise in so long a distance it would have little chance 

 of alighting exactly upon the trunk." Its food consists 

 chiefly of leaves. 



Order 4. Chiroptera (Bats). — The bats form a well-cir- 

 cumscribed group of mammals, very distinct from any 

 other, especially in the greatly modified fore-limbs, the ra- 

 dius and ulna being united, and the second tc the fifth 

 metacarpal bones and phalanges being very long and slender, 

 supporting a thin, leathery membrane or skin, extending 

 to the hind legs, and wholly or partly enclosing the tail; 

 the hind toes being, however, free, as when at rest or in 

 the vegetarians when feeding, bats hang head downwards, 

 holding on by their claws. The sternum is slightly keeled 

 for the attachment of the muscles of flight. The mam- 

 mary glands are pectoral. In other respects, especially the 

 dentition, the bats resemble the Insectivora. The form of 

 the teeth differs from the ordinary insectivorous bats in 

 those which live on fruit. The vegetable-eating or fruit- 

 ing bats have a superficial resemblance to the flying lemurs; 

 and because their mammae are pectoral, have been placed 

 next to the Primates. 



Bats live in caves and in the hollow of trees by day; all 

 hibernate in the same situations, going into winter quar- 

 ters in the autumn, and reappearing in the warm twilight 

 of spring. Though the eyes are small, and the sight, so 

 far as we know, deficient in keenness, they show wonderful 

 skill in avoiding objects during their rapid flight. The ears 

 are very large, and in the vampires the nose is adorned 

 with sensitive, leaf-like growths of complicated form. Cer- 

 tain bats, but not the true vampires, are known to enter 

 houses and to suck the blood of sleeping persons, who 

 awake to find their feet covered with blood. 



The largest bats are the fruit bats or flying foxes (Ptero- 

 pus) of the East Indies, one species of which expands one 

 and a half metres (nearly five feet) from tip to tip of the 

 wings. They assemble in large flocks in the Moluccas to 

 eat fruit, by day hanging by thousands on the trees. Our 



