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EL BOGOI TO MOMBASA 
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the legs appearing to be kept very upright, and unless hard 
pressed do not “ lay themselves out ” at all. Grevy’s starts 
off at a trot, with free, high action, and its movements recall 
those of the horse rather than the ass. Its head is held 
high, too, while the other keeps a more horizontal position 
of the neck. I have read that the trot is an acquired pace, 
peculiar to the domestic horse and not natural to it in its 
wild state. If so, the paces of Grevy’s zebra correspond more 
with our civilised horses’ than can those of their nearer wild 
relatives’. 
I have often been asked, when mentioning the fact that 
Equus burchelli. Equus grevyi. 
Zebra Hoofs. 
the two kinds of zebra are frequently found consorting 
together (it being especially common to see a single stallion 
grevyi in a troop of the smaller species), whether they do not 
cross breed. In reply to this question I say, certainly never. 
Wild animals of distinct species do not interbreed in a state of 
nature—unless, perhaps, very rarely, under quite exceptional 
circumstances; and then, probably, only owing to artificial 
causes, such as one kind being almost wholly exterminated by 
man. Even in the few recorded cases, the hybrid animals are 
often doubtfully so, and may be erroneously called by that 
name. I do not believe the females allow any such intercourse. 
That they graze together is nothing extraordinary ; many 
totally different kinds of herbivorous creatures are in the habit 
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