uniform colour; on the contrary, the monkey which we call _mone_, and the Greeks, _kébos_, has hair of different colours, and is vulgarly called the _variegated monkey_; this species was the most common of all those animals in the time of Aristotle; and from this character it obtained the name of _kébos_, which in Greek signifies a variety of colours. Thus all the animals of the ape, baboon, and monkey kind, mentioned by Aristotle, may be reduced to four, the _pithecos_, the _cynocephalus_, the _simia porcaria_, and the _kébos_; which we think ourselves sufficiently justified to rank as the _pithecos_ or _pigmy_, the _magot_, the _baboon_, and the _mone_, not only because their particular characters perfectly agree with those mentioned by Aristotle, but also, because the other species must have been absolutely unknown to him, since they are natives of those countries into which the Greek travellers of his time had not penetrated. Two or three ages after Aristotle, we meet with two new names in the Greek authors, _callithrix_ and _cercopithecos_, both relative to the long-tailed monkey. In proportion as discoveries were made, in the southern regions of Africa and Asia, we meet with new animals, and other species of monkies; and as most of these monkies likewise were not of various colours like the kébos, the Greeks composed the generic name of _cercopithecos_, that is, the _ape with a tail_, to denote all the species of monkies, or apes with long tails; and having discovered among them one of a beautiful green colour, they called it _callithrix_, which signifies beautiful hair. This callithrix is found in the southern parts of Mauritania, and in the neighbouring countries of Cape Verd, and commonly known by the name of the _green ape_. With respect to the other seven species of monkies, which we have indicated by the names of Macaque, Patas, Malbrouck, Mangabey, Moustac, Talapoin, and Douc, they were unknown to the ancients. The macaque is a native of Congo, the patas of Senegal, the mangabey of Madagascar, the malbrouk of Bengal, the moustac of Guinea, the talapoin of Siam, and the douc of Cochin-China; all these places were equally unknown to the ancients, and we have been careful to preserve the original names affixed to them in their native countries.