300 THE GEOGRAPHY OF MAMMALS 



a very limited distribution, but in former days the whole 

 series was connected, in locality as in form, by hosts of 

 ancestors now extinct. 



The Hippopotamidse, or Hippopotamuses, formerly 

 widely-spread over the whole world, have now only two 

 surviving species, the larger Hippopotamus amphibius, 

 which is met with in nearly all the great African lakes and 

 rivers, and the smaller Liberian Hippopotamus (H. 

 liberiensis) which has hitherto been found only in one of 

 the rivers of Liberia. As regards the existing creation, 

 therefore, this peculiar form of Ungulates must be re- 

 garded as strictly Ethiopian. 



The second family of Swine-like Ungulates — the Wart- 

 hogs (Phacochozridm) — is also entirely confined to Africa, 

 where two species are widely distributed from Upper 

 Nubia, throughout Eastern Africa, down to the Cape 

 Colony. 



The true Suidte, or Swine, to which the Wart-hogs are 

 indeed closely allied, embrace three genera — Sus, Pota- 

 mochcerus and Babirussa. The typical Swine (Sus) are 

 found in the southern part of the Palsearctic and the 

 Oriental Regions, extending from Southern Europe, through 

 Western Asia into India and the islands of the Indian 

 Archipelago. It is difficult in many cases to ascertain 

 what are the real wild species of this group, the domestic 

 forms having varied much under domestication for many 

 ages and having been carried by man all over the world. 

 It is probable that the Swine of New Guinea — the so-called 

 Sus papuensis — and those of other Eastern islands may be 

 descendants of domestic or semi-domestic animals. 



In the Ethiopian Region the place of Sus is taken by 

 the River-hog (Potamochoerus), with a slightly different 



