THE EAR IN ANTHROPOIDS 5 
The chimpanzee has never been observed to indulge 
in this expression of the emotions. To call the gorilla 
untamable is not perhaps quite fair to the gorilla. 
These beasts live so short a time in captivity, so far as 
experiments have shown, that there has been but 
little time to put the belief to the proof. The gorilla 
possesses the requisite physical basis for educatability. 
The brain is on the average, says Dr. Keith, larger than 
that of the chimpanzee, though the highest records 
among the chimpanzees beat the lowest record among 
gorillas. As to its complex structure, the brain of both 
differs in no essentials from the human brain, and the 
ancient controversy about the “ hippopotamus minor,” 
as Kingsley called it, has been laid to rest long since. 
Blackness of visage does not distinguish the gorilla, 
as was once thought when every chimpanzee with a 
black face was gravely suspected of being a gorilla 
or the result of a mésalliance between the one and the 
other. But the smaller and more refined-looking ear 
of the gorilla, somewhat like that of the eastern Anthro- 
poid, the orang-utan, contrasts with the big ears of the 
chimpanzee, and is on the whole an external mark of 
difference between them. Any one can observe for 
himself that the human ear is liable to great variations, 
and some persons are chimpanzee-like, while others 
come nearer to the gorilla in this feature. The general 
structure of the two apes leads to the conclusion that 
the gorilla is the older type, and the chimpanzee the 
more modified. But this is not wholly true, for the 
chimpanzee has retained the undoubtedly more primi- 
tive aboreal mode of life to a fuller degree than the gorilla, 
whose likenesses in this respect to man are not so much 
an indication of special relationship as a parallel diverg- 
ence from the normal, so far as apes are concerned. 
These adaptations to an arboreal life have left their 
mark upon the outward appearance of both anthropoids. 
26 
