344 STRUCTURE AND ADAPTATION OF TEETH 



without a corresponding increase in the vohime of 

 the brain. 



The striking contrast presented by the larger 

 apes, in their docihty during the earher period 

 of life, and their moroseness and intractability in 

 adult age, is thus easily accounted for; for in 

 proportion as their bodily powers increase, their 

 intelligence degenerates ; and as they attain to 

 years of maturity, the animal powers and propen- 

 sities acquire increased ascendancy over the higher 

 faculties, until at length they are as remarkable 

 for ferocity as formerly for gentleness. 



In the specimen to which I have referred (the 

 young orang), the whole of the deciduous teeth 

 are present, and the first permanent molar has 

 made its appearance ; the dentition exhibiting an 

 exact correspondence with that of a child in its 

 seventh year, excepting in the exaggerated size, 

 angular forms, and relative position of the several 

 classes of teeth. 



These animals employ their powerful incisor 

 teeth in tearing open the tough fibrous husk of 

 the cocoa-nut, and in cutting asunder roots and 

 stems; the remarkably "prominent cusps of the 

 molars indicating their fitness for the comminution 

 of such aliment. 



The presence of large canines does not neces- 

 sarily involve carnivorous habits, unless the molars 

 are ' of the laniary or flesh- cutting type. In the 

 Muntjak deer, for example, a ruminant animal, 



