more graceful. Though Zebra markings are not usual upon E. caballus, there are plenty of examples of—what we may perhaps in this case term—a "reversion" to a striped state. The celebrated "Lord Morton's mare,"[1] whose portrait hangs in the Royal College of Surgeons, is an interesting case of this. It was as a matter of fact thought to be an example of that rather doubtfully-occurring phenomenon, "telegony." Its history is briefly this. The animal was the offspring of a mare that had previously produced to a male Quagga a hybrid foal. Afterwards a second foal was produced by the same mare to an Arab sire. This foal, the one in question, was striped, and hence was thought to be an example of male prepotency. But instances are known of unquestioned Horses which show the same stripes, such as a Norway pony which had not even seen a Zebra!
A last remnant of the naked palm of the hand and sole of the foot is left in the shape of a small bare area, smaller in the Horse than in the Asses, known technically as the "ergot," the term being that of the French veterinarians. As already mentioned, the Horse differs from the Asses and Zebras in the fact that the hind-limbs have callosities on the inner side. They are known as "chestnuts," and their nature has been much disputed. It has been suggested that they are the last rudiment of a vanished toe; but in all probability they are, as already suggested, traces of glandular structures, which are common, upon the limbs in many animals (see above, p. 12).
It is a singular fact that there are apparently no wild Horses of this species. The case is curiously analogous to that of the Camel, which also is only known as feral or domesticated. Why the Horse should have become extinct as a wild animal, considering that when it does run wild it can thrive abundantly, is impossible to understand. Sir W. Flower thinks[2] that "the nearest approach to truly wild horses existing at present are the so-called Tarpans, which occur in the Steppe country north of the sea of Azov between the river Dnieper and the Caspian. They are described as being of small size, dun colour, with short mane and rounded obtuse nose." But he adds that there is no evidence to prove whether they are really wild. In favour, however, of their possibly being wild and indigenous European Horses, may be
