272 AFRICAN GAME ANIMALS 



two to the level of the nasal bones, the tip of the process 

 giving rise on the sides of the snout to a low, hairy wart. 

 Bush pigs differ further by the loss of the first lower pre- 

 molar, which in the common pig is a fairly well-developed 

 tooth lying isolated midway between the second premolar 

 and the enlarged lower canine tooth. The female differs 

 from Sus by the lesser number of mammae, which are but 

 three pairs. In coloration bush pigs may usually be known 

 by their bright-red color, and on this account they are often 

 called red river-hogs, a term, however, which is applicable 

 only to the West African species, porcus. In eastern Africa 

 the old boars usually lose their red color, which is replaced 

 by black in adult life, at which time they assume quite a 

 dark coat, relieved only by the whitish mane and head. 

 The newly born young are marked by longitudinal stripes 

 of pale-yellow or buff on a dark-brown ground-color. Bush 

 pigs are inhabitants of forest or dense bush country and 

 are found everywhere in Africa where such cover occurs, 

 from the Cape to the northern frontiers of Abyssinia and 

 the Soudan, and from sea-level to the upper limits of forest 

 growth, or to an altitude of ten thousand feet in the equa- 

 torial highlands. Several fossil species have been found in 

 the Miocene of India which have a close resemblance to 

 bush pigs in tooth structure, but the evidence is too frag- 

 mentary to warrant their identity with Potamochcerus, 

 which is quite unrepresented in the later Tertiary beds of 

 Asia or Europe. A race known to naturalists as larvatus 

 exists at the present time on the island of Madagascar, 

 but as it is scarcely distinguishable in either color or skull 

 characters from the mainland races, it is doubtless a recent 

 importation through the agency of man and has no signifi- 

 cance as showing a recent land connection between Mada- 

 gascar and the continent of Africa. The mammal fauna of 

 Madagascar is so peculiar and limited to so few types that 

 the island must have remained isolated throughout most 

 of the Tertiary time to have prevented the introduction of 

 any of the modern African forms of antelopes and car- 

 nivores. The only other existing African ungulate which 

 had representatives in Madagascar is the pygmy hippo- 

 potamus, which was represented by two species during the 

 rleistocene age on the island. Two species of bush pig are 



