5. _The Bonasus of Aristotle is the same as the bison of the Latins._ This proposition cannot be proved, without a critical discussion, with the whole detail of which I shall not trouble the reader. Gesner, who was a learned man, as well as a naturalist, and who thought with me, that the bonasus might be the bison, has more carefully than any other person examined and discussed the observations which Aristotle gives on the bonasus, and at the same time has corrected many erroneous expressions in the translation of Theodore Gaza, which nevertheless all the naturalists have followed without examination: in adopting, therefore, his elucidations, and in suppressing from the remarks of Aristotle, whatever is obscure, contradictory or fabulous, they appear to me reduced to the following description: The bonasus is a wild ox of Poeonia, and is at least as big as a domestic ox, and of the same make; he is covered from the shoulders to the eyes with a long hair, like the mane of a horse; his voice is like the ox; his horns are short, and curved round the ears; his legs are covered with long hair, soft as wool, and his tail is small compared to his size, although in other respects it resembles that of the ox. Like the bull, he has the custom of pawing the ground with his feet; his hide is hard, his flesh is tender, and good. By these characters, which are all we can rely on from Aristotle, we see how near the bonasus approaches towards the bison. Every part, in fact, agrees, the shape of the horns excepted, but which, as we have already observed, greatly varies in animals, who are, notwithstanding, of the same species. We have seen such crooked horns, taken from an hunched ox of Africa, and we shall hereafter prove, that this hunched ox is no other than the bison. This we shall be able to confirm by the testimonies of ancient authors. Aristotle mentions the bonasus as an ox of Poeonia; and Pausanias, speaking of the Poeonian bulls, says, in two different parts of his works, that these bulls are bisons; he even expressly says, that the bulls of Poeonia, which he saw at the public games at Rome, had very long hair upon the breast, and about the jaws. In short, Julius Cæsar, Pliny, Pausanias, Solinus, &c. in speaking of wild oxen, mention the aurochs and the bison, but take no notice of the bonasus. It must, therefore, be supposed, that in less than four or five centuries the species of the bonasus has been lost, unless we allow that the names _bonasus_ and _bison_ indicate only the same animal.