climates men would degenerate, as well as animals, after a certain number of generations. Another influence of the climate and food is, the variety of colours in the coats of animals: those which are wild, and live in the same climate, are of the same colour, which becomes a little lighter, or a little darker, in the different seasons of the year; on the contrary, those which live in different climates are of different colours, and domestic animals vary so much, that there are horses, dogs, &c. of all colours, while the stags, hares, &c. are almost uniformly of the same. The injuries of the climate, always the same, and constantly eating the same food, produce, in wild animals, this uniformity. The care of man, the comforts of shelter, the variety of food, efface and vary the colour in domestic animals; as does also the mixture of foreign racers, when no care has been taken to assort the colours of the male and female, which sometimes produces beautiful singularities, as we see in pied horses, where the black and the white are so whimsically mixed that they sometimes do not seem the work of nature, but rather the fancy of a painter. In coupling horses the colour and height should be attended to; the shapes should be contrasted, the race should be mixed with opposite climates, and horses and mares bred in the same stud should never be coupled together. All these are necessary cautions, and there are still some others not to be neglected; for example brood-mares ought never to be docked, because, being unable to defend themselves from the flies, they are continually tormented, and the constant agitations which the stings of these insects occasion diminish the quantity of their milk, which has great influence on the temperament and size of the foal, which in every respect will be more vigorous as the mother is more capable of nursing it. It is also preferable to choose brood-mares from such as have always been kept at grass, and have never been hard worked. Mares which have been kept in stables on dry food, and are afterwards put to grass, do not immediately conceive; they must have time to accustom themselves to this new kind of nutriment. Although the usual season of mares is from the beginning of April to the end of June, yet it frequently happens that some are so before that time; but which it would be better to let pass off, because the foal in such case would be brought forth in winter, and suffer both from the intemperance of the season, and badness of milk; and also, if a mare does not become proud till after the month of June, she should not be suffered to take horse, because the foal being produced in summer, cannot acquire strength enough to resist the injuries of the ensuing winter.