AFRICAN MONKEYS. 163 



resisting any intrusion upon it. The African Monkeys are mostly 

 of small size ; and are remarkable for the agreeable variety and 

 intermixture of their colours, and for their playful, lively dispo- 

 sitions. They are classed under two genera, Colobus and Cerco- 

 pithecus. Of the genus Colobus little is at present known, no 

 specimens having been brought alive to Europe ; and, of several 

 of its species, only mutilated skins having been examined. The 

 reason of this is partly that the skins are much valued by the 

 negroes on account of their long, soft, silky hair ; and that the 

 hunters will not be at the trouble of skinning and preparing the 

 head and limbs, so long as the fur of the body is the only part of 

 value to them. It is certain, however, that numerous species 

 exist, which may be all readily distinguished from those of the 

 Cercopithecus by this simple and apparently trifling character, 

 that the hairs of the former are of the same colour throughout, 

 although different hairs have different hues, whilst the hairs of 

 the latter are marked by rings of various shades. Thus a very 

 small piece of the skin will enable us to separate the two genera ; 

 but the character which essentially distinguishes them, is the 

 absence of the thumb from the hands of the Colobus, and its 

 presence in the Cercopithecus. It has been stated that in the 

 Semnopithems, this organ is but slightly developed ; still, how- 

 ever, it can be opposed to the fingers. In some species of the 

 Colobus a rudiment of it is perceptible ; but this never rises 

 above the skin, and is totally destitute of motion : and in what 

 may be regarded as the typical species, it is entirely absent. 

 This deficiency is in some degree compensated by the great 

 length of the other fingers. The habits of the Colobi re- 

 semble those of their Asiatic representatives the Semnopitheci. 

 and their stomachs are larger than those of ordinary Monkeys, 

 and exhibit the same complication of structure as those of 

 their eastern relatives, although they possess fully-developed 

 cheek-pouches. 



153. To the genus Cercopithecus belong nearly all the Monkeys 

 of the Old World, with which we are most familiar ; and it may 

 probably be regarded as the typical genus of the tribe, possess- 

 ing, as it does, in a pre-eminent degree, all the characters which 



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