20 
NATURAL HISTORY. 
Suddenly the roaring ceased. I stopped, thinking that it was a male, which was preparing to 
advance on me. But I listened in vain — the beast had fled. When I reached the spot I saw 
nothing but broken branches of trees. I measured some of them with my thumb, and found boughs 
of five inches diameter broken in two by the powerful grip of this monster of the forest. Although 
disappointed in my chase, I was glad to find a corroboration of the explanation I had given of 
the wearing down of the animals’ front teeth, for some of the branches plainly bore the tooth- 
marks.” 
As the teeth of the Gorilla are admirably adapted for their duties of masticating and biting 
vegetable food, sometimes soft and sometimes hard, and as they resemble in number and general 
arrangement those of man, it is necessary to notice them briefly. They are of three kinds, the front 
ones, which bite when the jaw is moved up and down, the large eye teeth (or dog teeth), which pierce, 
and the back teeth, which crush and grind. The first-mentioned are called incisor teeth or cutters, and 
there aie four in the upper and four in the lower jaw, as in man j the inner two in each jaw being 
UPPER JAW. 
UNDER JAW. 
THE TEETH OF THE GORILLA. 
larger than the outer two. They project slightly, and those of the upper jaw cut on the lower ones, 
and are, when the jaws are clenched, in front or “over-hung.” In shape they are adapted for biting 
a piece out of anything, and they have one fang each, which fits into a socket in the jaw. In the 
upper jaw there is a space between the incisor teeth and the great eye or dog teeth. This is one 
of the matters which distinguish the jaw of the Gorilla from that of man, whose teeth are continued 
in a row without any spaces where the gum is visible between them. The cause of the space is that 
the lower eye tooth is so large and long that when the mouth is closed it fits in there. This space is 
called a “ diastema,” and, as it is a term which will often be mentioned, it is necessary to notice that it 
is taken from the Greek word Siao-r^a, “an interval.” In the lower jaw the incisor teeth are succeeded 
by the eye teeth without any diastema. The eye or dog teeth are usually called canines, from Cants, a 
dog, they being very distinct in that animal. They are four in number, two being in each jaw, one 
on either side, and those of the upper jaw are long and pointed, being rounded, moreover, outside, 
and marked by grooves inside. The lower canines are nearly as large as the upper ones, and, as already 
noticed, fit in the diastema in front of those of the upper jaw. 
Behind the canine teeth are, on each side in both jaws, five crushing teeth, that is to say, ten 
in each jaw, and twenty in all. In the upper jaw there is a continuous row of teeth from the canines 
in front to the last of the crushers, which occupy the position of the upper wisdom teeth of man, but 
in the lower jaw there is not tins serried row of teeth, for, between the crushing ones and the canine, 
there is another space or diastema into which the upper canine tooth fits when the mouth is closed. 
