676 AFRICAN GAME ANIMALS 



fold or protocone of enamel Is enlarged. Notwithstanding 

 this similarity of structure, the various groups which are 

 recognized by distinct English names have been employed 

 as genera by some writers, who divide the genus up into 

 zebras {Hippotigris), asses {A sinus), and the horse {Eqmis), 

 on the basis of external differences. Unfortunately, when 

 we come to consider the fossil species such differences cannot 

 be employed, and we are at a loss to know whether in these 

 extinct species we are dealing with zebras, asses, or horses. 

 The fossil species first make their appearance in the Upper 

 Pliocene and the genus continues on down through the 

 Pleistocene to the present time. The former range covered 

 North America, Europe, Asia, and North and South Africa, 

 being absent only from South America. Recently the first 

 specimen of fossil horse has been recorded from South 

 Africa by Broom. It is based on some tooth remains from 

 Pleistocene deposits near Cape Town, which Indicate a 

 very large species apparently exceeding the horse In size. 

 The existing representatives occur in a small part of central 

 and southern Asia and Africa. In the latter continent they 

 extend from the northeastern portion southward along the 

 eastern half to the Cape region and southwest coast as far 

 north as Angola. The number of living representatives 

 does not exceed six or seven valid species, which are com- 

 prised in the horse, two zebras, and three or four species of 

 asses. 



The Bonte-Quagga or Quagga Zebra 



Equus quagga 



Equus quagga Gmelin, 1788, Systema Naturae, p. 213. 



The name quagga has been derived from the call of the 

 zebra, which consists of a short bark, kwa-ha, repeated sev- 

 eral times. The name came originally from the Hottentot 

 word quaha, through the Cape Dutch, who applied It first 

 to the true quagga and later distinguished the other or more 

 fully striped races as bonte-quaggas. The quagga has by 

 most recent writers been considered a distinct species from the 

 Burchell zebra and its northern races owing to the restriction 

 in the quagga of the stripes to the forward part of the body. 

 It is, however, less widely separated in coloration from the 



