The _Macaco_ apes constitute another genus, which forms the link between the guenons and the baboons, or dog-headed monkeys. They are neither exclusively African nor Asiatic monkeys, since species of macacoes are found in both these continents. They are usually subdivided into the macacoes with long tails, and those with short tails; and there is one species which wants this appendage altogether. This is the Magot-- perhaps the most noted of all the macacoes, since it was the earliest known to European nations, and is, in fact, the only species that is indigenous to Europe. It is the magot that inhabits the Rock of Gibraltar. Much has been written as to whether this monkey is really indigenous to Europe--some naturalists alleging that it reached Gibraltar from Africa, where it is also common. But it is not generally known that, on European ground, the magot is not confined solely to the Gibraltar Rock. It is also found in other parts of the south of Spain; and, it is likely enough, has existed there long enough to claim the character of a native. In the chain of natural affinities, the _Baboons_, or dog-headed monkeys, stand next to the macacoes. These are more of a quadruped form than any yet mentioned; and, both in a moral and physical sense, they are certainly the ugliest of animals. The hideous Drills and Mandrills, so well-known in our menageries, belong to this genus; as also the Chacma, or great dog-monkey of the Cape. There are, in all, seven or eight species of baboons, and most of them inhabit Africa. One of the most singular of them, the Hamadryas, extends its range into Arabia; while another, the Black Baboon, is an inhabitant of the Philippine Isles. With the baboons we close our list of the Monkeys of the Old World; but, in order to complete the account of these quadruped mammalia, it is necessary to find a place for those strange creatures usually known as Lemurs. These are usually grouped by themselves, and in a classification succeed the American monkeys--to some of which they have a greater resemblance than to those of the Old World; but, as they are all exclusively inhabitants of the latter, they may appropriately be noticed here.