THE TROPICAL FOREST 107 
antelopes have become modified for forest life. ‘This is 
especially true of the little duikerboks (Cephalophus), 
whose slender bodies enable them to glide through the 
undergrowth. The African harnessed antelopes (Trage- 
laphus) also, and the African sable antelopes (Hippo- 
tragus) are found in wooded country. In the African 
tropical forest also is found the rare and little-known 
okapi, a relative of the giraffe, but with stripes recall- 
ing those of a zebra (Fig. 46). 
In tropical Asia the sambar and its allies are the chief 
deer of forests, but the muntjacs (Cervulus) also haunt 
wooded country, choosing upland regions. In the 
dense jungles of South-East Asia occur various members 
of the genus Tragulus, including small, almost rodent- 
like animals, of primitive structure, called chevrotains. 
They are the smallest of living ungulates, being only 
about a foot in height, and their slender legs and bodies 
enable them to glide through the jungle, and thus to 
persist despite their generalized structure. An allied 
form, the water chevrotain, occurs on the west coast 
of Africa, where it inhabits swampy regions. 
In a densely forested region, rivers or swamps, with 
their special types of vegetation, obviously afford 
advantages to animals not fitted for arboreal life 
proper. We find, therefore, that such parts of the forest 
have special animals. The wild pigs of India and the 
adjacent regions, the bush pigs.of Africa, are examples 
of forms which haunt the damper parts of forests. 
Africa has also its hideous wart-hogs (Phacochoerus) 
while the islands of Celebes and Buru lodge in their 
forest the curious babirusa with its enormously elon- 
gated tusks. America has no true pigs, but the slender- 
limbed peccaries replace them, and are similarly 
inhabitants of the swampy parts of forests. All these 
