One thing which tends to lessen this in the gorilla is the size of the muscles about the ankle and the flexibility of that joint. Also the joint of the knee, being much larger in proportion to the leg, makes the calf appear smaller than it really is.
The corresponding part of the arm is more like that part of the human body.
In a sitting posture the gorilla rests his body upon the ischial bones, with his legs extended or crossed, while the chimpanzee usually squats, resting those bones upon his heels. He sometimes sits, but more frequently squats. When in these attitudes, both usually fold their arms across their breasts.
The hair of the gorilla is irregular in growth. It is more dense than that of the chimpanzee, but less uniform in size and distribution. On the breast it is very sparse, on the arms, long, and on the back, dense, and interspersed with long coarse hairs. The ground of colour is black, but the extreme end of the hair is tipped with pale white. This is so in early youth, and with age the white encroaches, until, in extreme age, the animal is quite grey. The top of the head is covered with a thick growth of short hair, of a dark tan colour, which looks almost like a wig. This mark seems to be peculiar to certain localities, but is uniform among those captured in the Fernan Vaz basin.
YOUNG GORILLA WALKING
A white trader living on this lake claims to have seen a gorilla which was perfectly white. It was seen on the plain near the lake. It was in company with three or four others. It was thought to be an albino, but in my opinion it was only a very aged specimen turned grey. A few of them have been secured that were almost white. It is not, however, such a shade of white as would be found in an animal whose normal colour is white. I cannot vouch for the colour of this ape seen on the plain, but there must have been something peculiar in it to attract so much attention among the natives.
So far, only one species of this ape is known to science, but there are reasons to believe that two species exist. In the forest regions of Esyira the natives described to me another kind of ape, which they averred was a half-brother to the gorilla. They know the gorilla by the native name njina, and the other type by the name ntyii. They did not confuse this with the native name ntyigo, which is the name of the chimpanzee, nor with kulu-kamba, all of which are known to them; but they described in detail, and quite correctly, the three known kinds of ape, and in addition gave me a minute account of the appearance and habits of the fourth kind, which I believe to be another species of the gorilla. They claim that he is more intelligent and human-like than any one of the others; and they say that his superior wisdom makes him more alert, and therefore more difficult to find. He is said always to live in parts of the forest most remote from human habitation.
The dental formula of the gorilla is the same as that of man, but the teeth are larger and stronger, and the canine teeth are developed almost into huge tusks. One thing to be remarked is the great variety of malformations in the teeth of this animal. It is a rare thing to find among them a perfect set of teeth, except in infancy. The cause of this appears to be violence or accident.
The eyes of the gorilla are large, dark, and expressive, but there is no trace of white in them. That part of the eye which is white in man is a dark coffee-brown in the gorilla, but becomes lighter as it approaches the base of the optic nerve. The taxidermist or the artist, who often furnishes him with a white spot in the corner of his eye, does violence to the subject; and those who pose the animal with his mouth open like a fly-trap, and his arms raised like a lancer, ought to be banished from good society. It is true that such things lend an aspect of ferocity to the creature, but they are caricatures of the thing they mean to portray.