24 
among monkeys. Finally, they are all inhabitants of the old 
world. 
The Gibbons are the smallest, slenderest, and longest- 
limbed of the man-like apes: their arms are longer in pro- 
portion to their bodies than those of any of the other man- 
like Apes, so that they can touch the ground when erect ; 
their hands are longer than their feet, and they are the only 
Anthropoids which possess callosities like the lower monkeys. 
They are variously coloured. The Orangs have arms which 
reach to the ankles in the erect position of the animal; their 
thumbs and great toes are very short, and their feet are longer 
than their hands. They are covered with reddish-brown hair, 
and the sides of the face, in adult males, are commonly pro- 
duced into two crescentic, flexible excrescences, like fatty tu- 
mours. The Chimpanzees have arms which reach below the 
knees ; they have large thumbs and great toes, their hands are 
longer than their feet, and their hair is black, while the skin of 
the face is pale. The Gorilla, lastly, has arms which reach to 
the middle of the leg, large thumbs and great toes, feet longer 
than the hands, a black face, and dark-grey or dun hair. 
For the purpose which I have at present in view, it is un- 
necessary that I should enter into any further minutie 
respecting the distinctive characters of the genera and species 
into which these man-like Apes are divided by naturalists. 
Suffice it to say, that the Orangs and the Gibbons constitute 
the distinct genera, Simia and Hylobates; while the Chim- 
panzees and Gorillas are by some regarded simply as distinct 
species of one genus, Zroglodytes; by others as distinct 
genera—Troglodytes being reserved for the Chimpanzees, 
and Gorilla for the Engé-ena or Pongo. 
Sound knowledge respecting the habits and mode of life of 
the man-like Apes has been even more difficult of attainment 
than correct information regarding their structure. 
Once in a generation, a Wallace may be found physically, 
mentally, and morally qualified to wander unscathed through 
