298 AFRICAN GAME ANIMALS 



to these dimensions the largest British East African skulls 

 are: male, 28^ inches, female 25^^ inches. Specimens of 

 the skulls of the Nile hippopotamus have been examined 

 from the Victoria Nyanza, White Nile, Lado Enclave, Blue 

 Nile, and Atbara River. On the White Nile hippopotamuses 

 were observed as far north as Jebelein, 13 degrees north 

 latitude, by the members of the Roosevelt expedition in 

 1910. This point is well beyond the sudd area, where the 

 conditions are quite arid and the desert margins of the 

 river at this point form a natural barrier to the northward 

 extension of the hippopotamus. Farther northward and 

 eastward they occur in the upper waters of all the tribu- 

 taries of the Nile having their sources in the Abyssinian 

 highlands. 



East African Hippopotamus 



Hippopotamus amphibius kiboko 



Native Names: Swahili, kiboko; Kikuyu, nguo ; Masai, olmakau. 

 Hippopotamus amphibius kiboko Heller, 1913, Smith. Misc. Coll., Vol. 61, 

 No. 22, p. I. 



Range. — From the Rift Valley of East Africa eastward 

 to the seacoast, north as far as southern Abyssinia, and 

 southward through German East Africa; limits of range 

 not known. 



A series of five specimens of hippopotamus shot by 

 Colonel Roosevelt at Lake Naivasha are in the National 

 Museum. The skulls of these specimens show such con- 

 stant differences from Nile specimens that they have been 

 recently recognized as a new race by Heller. This new 

 East African race is characterized by the wide nasal bones, 

 great elevation of the orbits, and the lambdoidal crest above 

 the interorbital region, which has a deeply concave surface 

 in consequence, and the less constriction of the rostral part 

 of the skull. From typical amphibius of the Nile it is 

 further distinguishable by its smaller body size and smaller 

 canine teeth. It may be distinguished from capensis of 

 South Africa and the Zambesi River system by its more 

 circular orbit, the lighter body coloration, and the more 

 heavily haired ears and tail tuft. 



