Chapter XXII.

1. Both the horse and mare begin to use sexual intercourse at two years old. Such early cases, however, are rare, and their offspring small and weak; and generally they commence at three years old, and they continue to produce better colts till they are twenty years old. The period of gestation is eleven months; parturition takes place in the twelfth. The male does not impregnate the female in any particular number of days; but at times in one, two, or three, sometimes in more. The ass mounts and impregnates more quickly than the horse; and the act of intercourse is not laborious in horses as it is in oxen. Next to the human subject, the horse in both sexes is the most lascivious of all animals. The sexual intercourse of the younger horses takes place before the usual age according to the goodness and abundance of their food. The horse generally produces but one colt, or sometimes two at the outside. The hemionus has also been known to produce two, but this is considered extraordinary. The horse begins sexual intercourse at thirty months old, so that it can produce proper colts when it has done changing its teeth. Some have been known, they say, to impregnate mares while changing their teeth, unless they were naturally barren.

2. The horse has forty teeth. It sheds its four first teeth at thirty months old, two above and two below. A year afterwards, it sheds four more in the same manner, two above and two below. And again, at the end of the next year, it sheds four more in the same manner. When it is four years and a half old, it sheds no more; and individuals have been known to shed them all at first, and others that have shed them all in the last year. These circumstances are rare, so that it usually happens that the horse is most fit for sexual intercourse at four years and a half old. The older horses are more full of semen, both the males and the females, than younger ones. Horses will copulate both with their dams and with their offspring; and it is thought to be a sign that the herd is complete, when they copulate with their offspring. The Scythians ride upon their pregnant mares when the embryo begins to turn in the uterus, and say that it renders parturition more easy. All other quadrupeds lie down in the act of parturition; wherefore their young are always produced lying on their side; but when the mare feels that the time for parturition is approaching, she stands upright to part with her colt.

3. Horses generally live eighteen or twenty years; some live twenty-five or thirty years; but if they are carefully treated, their life may be extended to fifty years. Thirty years, however, is a very long life for the male, and twenty-five for the female. Some have been known to live forty years. Males live a shorter time than females, on account of the act of sexual intercourse; and those that are brought up separately longer than those which live in herds. Females attain their proper length and height in five years; the males in six. In six more years the fulness of body is acquired, which continues till they are twenty years old. The females attain perfection more rapidly than the males; but in the uterus the males are the more rapidly developed. This is also the case in the human subject. This also takes place in those animals which produce several at a birth.

4. They say that the mule sucks for six months, but the mare will not permit it to come afterwards, because it drags and hurts her. The horse sucks for a longer time. The horse and the mule attain perfection after casting their teeth; and when they have cast them all, it is not easy to know their age. Wherefore they say that, before casting its teeth, the horse has its mark, which it has not afterwards. After the teeth have been changed, the age is usually ascertained by the canine tooth; for that in riding horses is generally worn down, for the bridle rubs against it. In horses which have not been ridden, it is large and not worn. In young horses it is small and sharp.

5. The male copulates at all seasons, and as long as he lives; the female also as long as she lives; and at all seasons, unless they have on a fastening or some other hindrance, no peculiar time is appropriated for copulation in either sex, for there is no period of coition when they cannot also bring up their young. In Opus there was a horse in a herd which engendered when he was forty years old; but it was necessary to lift up his fore legs for him. Mares begin to desire sexual intercourse in the spring; and when the mare has foaled, she does not become pregnant again immediately, but waits for a time, and produces better foals at the end of four or five years. It is quite necessary that she should wait one year, and should pass through a fallow, as it were.

6. The horse, then, bears young at intervals, as I have observed; but the ass is not subject to intervals. Some mares are quite barren, and others, though they conceive, yet do not produce their young; and they give as a reason for this, that upon dissection the fœtus was found to contain other reniform bodies round the kidneys, so that it appeared to have four kidneys. As soon as the mare has foaled, she eats the chorion, and bites from the head of her foal the substance called hippomanes. In size this substance is somewhat less than a dry fig. Its form is flat and round, and its colour black. If any person is at hand to take it before the mare, and she smells it, the scent renders her wild and mad. For this reason it is sought after and collected by poisoners. If an ass copulates with a pregnant mare, the pre-existing fœtus is destroyed. Those who keep herds of horses do not place a leader over them, as they do over oxen, for they are not naturally stationary, but active and wandering.