508 QUADRUMANA. 



Asiatic relatives. The general absence of laryngal sacculi has been 

 already noticed ; the os hyoides, however, is always expanded anteriorly, 

 with its inner surface concave. The fur in the Cercopitheci is moderately 

 full and soft ; and its colours are often elegantly disposed and contrasted ; 

 it may be laid down as a rule, that the hairs are always annulated with 

 two or more tints ; and though the Patas may, at first, seem an exception, 

 it is not so in reality. 



The skull in the Cercopitheci (see fig. 289), compared with the skull 

 in the Semnopitheci, differs in several details. In the first place, the 



orbits are thrown less outwardly ; they 

 approach each other more closely, the 

 inter- orbital space being very narrow ; in 

 the next place, the superciliary ridge is 

 less bold, depressed, and angular; it 

 gives a less frowning aspect to the orbits, 

 the outer margin of which is far less 

 projecting, and squared. Again, in the 

 Cercopitheci, the facial bones project 



Skull of Cercopithecus sabams. .. . . r / 



more sensibly, giving an acuter angle to 



the face ; but the lower jaw is less deep ; and the chin retracts more 

 obliquely. The skull is rounded and slightly flattened in front; the 

 dentition need not be recapitulated ; the incisors, especially the middle 

 pair above, are large and oblique ; the canines, which are of considerable 

 magnitude, are compressed, with a sharp cutting edge, posteriorly. 



The Cercopitheci resolve themselves into several small groups, or sets, 

 according to the mutual alliances of the species ; these are respectively 

 represented by the Patas, the Green Monkey, the Talapoin, and the 

 Pogonias ; while for the three White-eyelid Monkeys a sub-generic rank is 

 adopted. The sub-genus is here termed JEthiops, and is characterized 

 by the presence of a fifth tubercle on the last molar of the lower jaw, 

 by the magnitude of the upper middle incisors, and by the hairs being 

 destitute of annulations. 



