60 NATURAL HISTORY ESSAYS 



importance, and vice versa. Thus we have the 

 perplexing variations amongst the Felidae, as 

 instanced by the serval and the servaline cats, 

 or by the ocelot of America, with its fulvous, grey, 

 and pallid phases : the puzzling and unsolved 

 relationship between the European brown bear 

 ( Ursus arctos], the barren ground bear ( U. richard- 

 soni), and the grizzly ( U. horribilis] : whilst the 

 protean variations of the Burchell zebra (JE. bur- 

 c/iellii] are now ranked as sub-species under the 

 names of E. b^lrchell^^ chapmanii, granti, selousi, 

 and so on. It will thus be seen that not only are 

 wild animals liable to considerable variation, but 

 also that the study of this phenomenon alone would 

 occupy a lifetime. 



The splendid roan antelope ( Hippotragus equi- 

 nus) of Africa is a very unstable species, and 

 serves as an excellent example of animal variation. 

 It is distributed over a large portion of the African 

 continent, from the White Nile as far south as 

 and including the Transvaal ; while in former 

 times it was also found in Cape Colony, north of 

 the Orange River. It occurs in West Africa, but is 

 absent from the Congo forest region. With the 

 single exception of the eland, the roan is the 

 largest of all the magnificent antelopes of Africa, 

 and stands about 56 inches high at the shoulder, 

 its splendid proportions being enhanced by its 

 stately bearing and self-possessed carriage. The 



