THE TEETH OF THE HIGHER APES AND MAN 191 



and longer, than in man, but have the obliqne 

 ridge. These teeth are not so human as those of 

 the Chimpanzee and Orang. The lower molars 

 are similar and have the same pattern as in man, 

 but the second has the fifth cusp, which is wanting 

 in man. The third molars are larger than the 

 others, as the molar series increase in size from 

 first to last; in man the reverse is true. They 

 have ample room in the jaws, and are useful 

 grinders. The grinding teeth are very strong, 

 as the massive muscles of this great Ape are used 

 for biting and crushing with tremendous force. 



The Teeth of Man. The teeth of Man are 

 closely related in form and structure to those of 

 the apes below him, and remotely to various mem- 

 bers of the Quadrumana. Indeed, like other or- 

 gans, they bear in their structure the history of 

 a long line of descent, and many of the indica- 

 tions of their history can be read with some cer- 

 tainty. Some of his teeth are quite primitive in 

 type, as the quadritubercular molar, which is 

 found far back in the Eocene; and occasionally 

 this lapses into the still more primitive form of 

 the tritubercular molar. The teeth of Man in 

 general are degraded in form and structure and 

 much reduced in specialization as compared with, 

 for instance, the highly specialized teeth of the 

 Carnivora and Herbivora. The structural integ- 

 rity of the teeth is much more deficient in civilized 



