We have already remarked, that no species approaches so near each other, as that of the fallow-deer to the stag: nevertheless, the axis appears to be an intermediate shade between the two. He resembles the fallow-deer in the size of his body, length of his tail, and his coat, which is the same during his whole life: the only essential difference is in his horns, which nearly resemble those of the stag. The axis, therefore, may be only a variety depending on the climate, and not a different species from that of the fallow-deer; for, although he is a native of the warmest countries of Asia, he exists and multiplies easily in Europe. There are many herds of them in the royal menagerie; and they produce together as freely as the fallow-deer. It has never, however, been observed, that they mix either with the fallow-deer, or with the stags, and this is the cause of our presuming, that they are not a variety of one or the other, but a particular and intermediate species. But as no direct and decisive experiments on this subject have yet been made, and as no necessary means has been used to oblige these animals to unite, we will not positively affirm that they are two different species. We have already seen, under the articles of stag and fallow-deer, how many instances these animals give of varieties, especially in the colour of their hair. The species of the fallow-deer and stag, without being very numerous in individuals, is universally diffused; both are met with in either continent, and both are subject to a great number of varieties, which appear to form lasting kinds. The white stags, which are a very ancient race, since the Greeks and Romans mention them, and the small brown stags, which we have called _Corsican stags_, are not the only varieties of this species. There is in Germany another race, known in that country by the name of _Brandhertz_, and by our hunters by that of the _Stag of Ardennes_. This stag is larger than a common stag, and differs from other stags not only by its deeper colour, being almost black, but also by long hair upon the shoulders and on the throat. This kind of mane and beard give him some affinity, the first to the horse, and the latter to the goat. The ancients have given to this stag the compound names of _Hippelaphus_ and _Tragelaphus_. As these denominations have occasioned critical discussions, in which the most learned naturalists are not agreed, and as Gesner, Caius, and others, have said, that the hippelaphus was the rein-deer, we shall here give the reasons which have occasioned us to think differently, and have led us to suppose that the hippelaphus of Aristotle is the same animal as the tragelaphus of Pliny, and that both these names equally denote the stag of Ardennes.