GENERAL OBSERVATIONS ON THE QUADRUMANA. 
205 
above and below to a point at the elbow. This curious arrangement, so unlike that in most of the lower 
Mammals, is common to the Gorilla, Chimpanzee, Orang, some species of Hylobates, and even to some 
American Monkeys. It is not invariable in the same genus, for in Hylobates agihs the hair on the fore- 
arm is directed downwards, or towards the wrist, in the ordinary manner, and in Hylobates lar , it is 
nearly erect, with only a slight forward inclination. It can,” he adds, “ hardly be doubted that with 
most Mammals the thickness of the hair and its direction on the back is adapted to throw of! rain, and 
even the transverse hairs of the Dog’s leg may serve for this end when he is curled up asleep.” 
Mr. Wallace remarks that the convergence of the hair towards the elbow on the arms of the Orang 
serves to throw off the rain when, as is the custom of this animal, the arms are bent, with the hands 
clasped round a branch, or over its own head. But the previously-mentioned naturalist aptly remarks 
HEAD OF the BLACK HOWLER. (From the Proceedings of the Zoological Society.) 
that the attitude may not determine the direction of the hair; and that, on the contrary, the direction 
of the hair may determine the attitude. Of course the darkness of the negro makes any likeness, real 
or imaginary, with the Monkey, all the greater, and really the resemblance of the American Monkey — 
whose name (Satavas) indicates his ill looks — with its jet-black skin, white rolling eyeballs, and hair 
parted at the top of its head, to a young negro, is laughable enough. 
Any one who visits the Zoological Gardens soon becomes aware that there is a great variety of 
expression in the eyes and muscles of the face of Monkeys, and infinitely greater in amount than in 
any other animals, and in some points infinitely less than in man. Mr. Darwin has collected facts, and 
given the result of liis own observations upon the different methods of expression produced by the facial 
and other muscles, and the following is from his work on the li Expression of the Emotions”: — 
“ It is not possible to distinguish in Monkeys, at least, without more experience than I have had, 
the expression of pleasure or joy from that of affection. Young Chimpanzees make a kind of barking 
noise when pleased by the return of any one to whom they are attached. When this noise — which the 
keepers call a laugh — is uttered, the lips are protruded ; but so they are under various other emotions 
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