54 MOSTLY MAMMALS 
ancestor. Some of these Somali asses are, it is true, more 
striped on the legs than is commonly the case with the 
domesticated breed ; but then some examples of the latter 
are nearly or quite as fully marked as the wild race, while 
some African specimens have nearly uniformly coloured 
limbs. Possibly the Somali wild ass may originally have 
ranged into Syria and Arabia; and, in any case, it is 
probable that it was first tamed there, and thence intro- 
duced into Europe. Indeed, the Greek name (ovos) of the 
ass is stated to be derived from a Semitic root; and since 
this name occurs but once in the “Iliad,” and not at all 
in either the “ Odyssey” or in Hesiod, it has been inferred 
that the ass was a rare and little-known animal in Greece 
during the epic period. 
Whether any truly wild horses have _ survived till 
modern times has been disputed. With the exception of 
the Mongolian Przewalski’s horse, which does not seem 
specifically distinct from the domesticated Eguus caballus, 
the only animals which can lay claim to that title are the 
so-called tarpan of the steppes of Central Asia, which for- 
merly ranged as far westward as the Volga, but are now 
exterminated. Some authorities are of opinion that these 
tarpan are a truly wild race, while by others they are 
regarded as feral—that is to say, descended from a domes- 
ticated stock. It is certain that the droves of tarpan 
at times received an influx of feral animals; but whether 
they were feral or truly wild—and the evidence seems 
rather in favour of their wild origin—they undoubtedly 
resembled the ancestral type of the horse. This, of course, 
will be due in the one case to reversion, and in the other 
to direct inheritance. They were rather small, clumsily 
built animals, with remarkably ugly heads; their general 
colour being dun. During the Pleistocene period horses 
