However, as both the jackal and the adil are found in the same countries; as the species cannot have been altered by a long continuance in a domestic state, and as there is always a considerable difference in the size, and even in the dispositions of these animals, we shall look on them as distinct species, until it be proved that they intermix and produce together. Our presumption on the difference of these two species is the better founded, as it seems to agree with the opinion of the ancients. Aristotle, after having spoken of the wolf, the fox, and the hyæna, gives some obscure intimations of two other animals of the same genus, one by the name of the _panther_, and the other by that of the _thos_. The translators of Aristotle have interpreted _panther_ by _lupus canarius_, and _thos_ by _lupus cervarius_; that is, the dog-wolf and the stag-wolf. This interpretation sufficiently indicates, that they considered the panther and thos to belong to the same species. But I observed, under the article _lynx_, that the lupus cervarius of the Latins is not the thos of the Greeks. This lupus cervarius is the same as the chaus of Pliny, which is our lynx, and which has not a single character that agrees with the thos. Homer, when painting the valour of Ajax, who singly rushes among a band of Trojans, in the midst of whom Ulysses, wounded, was engaged; compares him to a lion that suddenly springs on a troop of the thos, surrounding a stag at bay, disperses and drives them away as mean and contemptible animals. This word, thos, the commentator of Homer interprets by that of panther, which he says is a kind of weak and timid wolf: thus, the thos and panther have been considered as the same animal by some of the ancient Greeks. But Aristotle seems to make a distinction between them, without, however, giving them any distinct characters. "The thos (says he) have their internal parts like those of the wolf; they copulate like dogs, and bring forth two, three, or four young ones at a time, which are born with their eyes shut. The body and tail of the thos are longer than those of the dog; his legs are shorter, but that does not prevent him from being as swift, and he can spring much further. The lion and the thos are enemies, because they both live upon flesh, and seek their food from the same source; hence disputes arise between them. The thos never attacks, and is but little afraid of the human species. He fights with the dog and the lion, whence the lion and the thos are never seen in the same places. The smallest thos is esteemed the best. There are two species of them, and some authors even make three.[A]" This is all Aristotle says concerning the thos, and he speaks still less about the panther; for he mentions it but in one single passage in the 35th chapter of the sixth book of his History of Animals, and there says, "the panther produces four young ones at a time, which are born with their eyes shut like young