190 COMPAEATIVE DENTAL ANATOMY 



tails of organization, the dentition of the Gorilla 

 is not so human as that of some of the lower Pri- 

 mates. That of the Chimpanzee is more close. 

 The diastema is still wide, and the canines are 

 large and baboon-like. The jaws are large and 

 square, the arch is a mere parallelogram, and the 

 brain-case is much smaller. The great ridges 

 erected to support the muscles of mastication are 

 very conspicuous. The incisors are of similar 

 shape to those of man, and relative sizes of the 

 central and lateral are nearly the same as that 

 of man. The crowns are coarses, square, heavy, 

 and roughly ridged. The canines are of great 

 size and strength, quite like those of the Baboons. 

 The crown is trihedral in section, with a groove 

 on the labial face and a cutting edge behind. It 

 stands out in such prominence as to give a fero- 

 cious look to the face, and adds to the square- 

 ness of the jaws. It is not as large in the female 

 as in the male. They erupt after the third molar, 

 which is the reverse in man. The upper pre- 

 molars are of bicuspid form, as in man, but the 

 cusps are more high and pointed, and are united 

 by a strong cross ridge. The uppers are im- 

 planted by three roots. The lower first premo- 

 lar is strong, pointed, and caniniform. The sec- 

 ond is tricuspid. Both are implanted by two 

 roots, like the true molars. The upper molars 

 are more strong and square, the cusps sharper 



