So far, only one species of this ape is known to science; but there are certain 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 do not confuse this with the native name _ntyigo_, which is the name of the chimpanzee. Neither is it a local name for the _kulu-kamba_. All of those apes are known to the natives. They described in detail, and quite correctly, the three known kinds of ape. In addition they gave me a minute account of the appearance and habits of a 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. 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 more remote from human habitation. On my next voyage I mean to hunt for this new species. 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 into 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 deficiency appears to be violence. 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. It 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. Those who pose him with his mouth opened 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. The ears of the gorilla are very small and lie close to the sides of the head. The model of them is much like the human ear. The lower lip is massive, and the animal frequently relaxes it, so that a small red line is visible between the lips. The usual height of the adult male gorilla, if standing quite erect, is about five feet ten inches. The tallest specimen that has ever been taken is a trifle more than six feet two inches. I shall not pursue the comparison into minute details, but shall leave that to the specialist, in whose hands it will be treated with more skill and greater scope. As my especial line of research has been in the study of the speech and the habits of these animals, I shall confine myself to that. But the general comparison made is necessary to a better understanding of these subjects. CHAPTER XXI