SAKI MONKEYS. 



177 



the forehead being of the same greyish-black colour as the bodj-. The moustache 

 Ls yellow. 



In the young of tliis species the moustache is white, while the uuder-parts of 

 the body are grey. 



The Red-Backed Saki {Pithecia chiropoies). 



Witli the red-backed siiki, wliicli was tirst obtained liy Humboldt on the banks 

 of the Urinoco, and also occurs in Guiana, we come to the first of another group of 

 tlie genus, distinguished in several points from all the species j-et described. 



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^^.s^:^;;^-- 







THE BLACK SAKI (J Hat. sizej. 



In the first place, the hair of the head, although ra<liating from a central point 

 in the young, in the adult is divideil by a median parting, and falls down on either 

 side. Then the long beai-d is divided by a gap in the middle of the chin into two 

 lateral moieties, while the fur on the body, instead of being long and harsh, is short 

 and soft. The tail also has shorter hair than in the last gi'oup, and is thick and 

 club-shaped. Finally, the hinder part of the lower jawbone is more expanded than 

 in the t^-pical group. The peculiar form of the neatlj'-divided and flattened hair 

 of the head gives these animals the appearance of wearing a wig. 



The general colour of the fur in this saki is blackish-brown, but there is a 

 considerable area on the back and shoulders of a yellowish-red tint, from wliich the 



VOL. I. —12 



