108 THE FAUNA OF 



pig-like animals differ from those ungulates which live 

 on hard ground in the greater number of functional 

 toes, in the way in which these toes spread out to pre- 

 vent the animal sinking in the mud, and in the absence 

 of the elaborate arrangement which enables a sheep 

 or an antelope to swallow large quantities of partially 

 masticated vegetable food, which is regurgitated and 

 thoroughly masticated later, when the animals feel 

 themselves relatively safe from pursuit. 



Among the odd-toed ungulates the tapirs, both the 

 Malayan form and those occurring in South America, 

 are forest animals, haunting much the same regions as 

 do the pigs. The great enemy of the American forms is 

 the jaguar, and the fact that when attacked the animals 

 endeavour to reach thick cover suggests that the forest 

 habitat is partially determined by the need for protec- 

 tion. As in the case of the pigs it is probably partially 

 determined also by the need for finding relatively soft 

 and succulent food, for the teeth of pigS and tapirs 

 have not the elaboration of structure found in the more 

 highly differentiated ungulates. 



The rhinoceroses show somewhat different conditions 

 in regard to habitat, for while some haunt more or less 

 open plains, others, like the Javan and Siimatran 

 rhinoceroses of South-East Asia and the conmion 

 rhinoceros of Africa, are found in forested country, and 

 subsist largely on leaves and twigs. Horses are not 

 forest animals. The elephants, on the other hand, both 

 Indian and African, are found in dense jungles, but in 

 both cases this seems to be largely on account of the 

 animals' great intolerance of heat, for they emerge 

 into the more open regions both at night and during 

 the cooler parts of the day. 



Among the rodents, the squirrels and flying squirrels. 



