588 ZOOLOGY. 
with the same habit of sleeping, head downward, holding on 
by its hind feet, is the Galeopithecus of the East Indies. 
This singular creature has been placed among the lemurs. 
by some authors. G. volans Pallas inhabits Java, Sumatra, 
Borneo, and Siam. 
Order 4. Chiroptera.—The bats form a well-circumscribed. 
group of mammals, very distinct from any other, especially 
in the greatly modified fore-limbs, the radius and ulna being’ 
united, and the second to 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, how- 
ever, 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 mus- 
cles of flight. The mammary glands are pectoral. In other 
respects, especially the dentition, the bats resemble the 
Insectivora. The form of the teeth differs from the ordi- 
nary insectivorous bats in those which live on fruit. The 
vegetable-eating or fruit-eating hats have a superficial resem- 
blance to the flying lemurs; and because their mamma are: 
pectoral, have been placed next to the Primates. 
