THE NEAREST ALLIES OF THE HORSE. 95 
marks on knees and hocks reappear frequently im’ horses, Darwin 
considers that if grey or red brown asses had been steadily selected 
and bred from, the shoulder stripe would have been as generally and 
| completely lost as in the horse. These markings are best seen in the 
male ; often when present in the young they disappear in adults. 
Size shows a neat gradation” from the wretched little 7-hand 
donkey of the Maharattas up to the 16-hand dray horse ; it varies 
enormously with domestication, but among the equines in the wild 
. state seems to range from 1] hands or 12 hands (onager and zebra) 
through 13 hands (quagga), and 13} hands (peechey) to 14 hands 
in the kiang, and still more in the wild horse. 
Aabits—All these wild equines are strong, hardy, swift-footed, 
courageous, but shy, and curious in the extreme. They vary much 
in tameability, but have ali been more or less brought under control, 
and they exhibit as much variety in character as we see in domestic 
horses. The liking of these animals for, and their ready association 
with, other species is remarkable. All seem to be fond of the gnu, 
and they do not object to the presence among them of so different 
acreature asthe ostrich. The gregarious instinct seems stronger 
in some forms, such as the zebra, than in others like the kiang, but 
the size of the troops is probably determined much by the amount 
of pasture available and the freedom from disturbance by man. 
The same influences determine the range, both African and Asiatic 
forms are retreating before the advancing steps of civilization, and 
they all seem to frequent the mountains in hot weather and the 
o 
plains in cold, according to the amount of pasturage available. The 
Kiang and zebra are most fond of mountains, the onager inhabits 
hills and sandy deserts, and the peechey grassy plains, These 
differences seem to be determined by local circumstances : in fact, 
the equine adapts himself to the conditions of his surroundings. 
The voice ranges from a neigh, so familiar in the horse, to a bray, 
equally familiar in the ass. The intervening sounds seem to vary 
as much as the tuneful notes of transport mules when the trumpet 
sounds ‘‘ feed.” 
The ears vary much in relative development as regards length, 
sharpness of tip, and fineness, exhibiting every gradation between 
the familiar auricle of the ass and the neat delicate corresponding 
part in the horse. 
. Our information as to osteological characters is very scanty, but 
it suffices to show us that the differences are simply those of 
