WILD TARPAN AND ITS RELATIONS 107 



inherit their colour, either directly or by reversion, 

 from the wild tarpan. This led Darwin ^ to conclude 

 that all the existing breeds of horses are probably 

 descended " from a single dun-coloured, more or 

 less primitive stock, to which our horses occasion- 

 ally revert." And although in the light of the 

 foregoing evidence as to the existence of more 

 than one type of Prehistoric wild horse in Europe, 

 this conclusion requires some little modification, it is 

 probably not far from the truth, though the Arab 

 may perhaps form an exception to the generalisation. 

 It being admitted, then, that the wild Mongolian 

 tarpan is related not only to some of the existing 

 horses and ponies of Western Europe, but likewise 

 to their Prehistoric ancestors, it seems only logical 

 that it should not be separated from the species 

 typified by domesticated horses, and its name will 

 therefore be Equus caballus przevalskii, or, at all 

 events, until it is definitely proved to be entitled to 

 a designation of earlier date. 



Adult stallions of the Mongolian tarpan stand 

 about 13. 1 hands (53 inches) at the shoulder; and, 

 as might naturally be expected, its nearest domesti- 

 cated representatives are the ponies of the same 

 district, which measure from about 12.2 to 13.3 

 hands, and in their rough, untrimmed coats are 

 very like their wild relatives, although they have 

 developed long, flowing manes, with forelocks, and 



1 op. cit., p. 65. 



