IN THE LOWER ANIMALS, ETC. 347 



rals being larger in proportion to the central 

 pair. 



The characters of the canine tooth are well 

 marked in its conical shape and the deeper im- 

 plantation of the root, but it rises in a small 

 degree only above the general plane of the teeth. 

 There is a greater difference in form and size 

 between the premolars (bicuspides) and the true 

 molars ; the former are more rounded : and 

 although we may occasionally meet with cases 

 in which the upper bicuspides are furnished with 

 three, and the lower with two fangs, this point 

 of resemblance to the lower type is comparatively 

 rare. The tubercles of the molar teeth are less 

 prominent, and the third molar is not so fully 

 developed. 



We have observed that even in the highest 

 Quadrumana the space in front of the upper and 

 behind the lower canine is as well marked as in 

 the Carnivora. In man alone the teeth are 

 arranged in an uninterrupted series ; and in the 

 well-formed jaw they exhibit a beautifully regular 

 parabolic curve, in place of the angular dispo- 

 sition of the teeth in the chimpanzee ; and the 

 difference between the sexes is no longer indi- 

 cated by the greater size of the canines in the 

 male. (Fig. 60.) 



In harmony with the more delicate contour of 

 the human teeth, the jaws and their processes are 

 far less massive than in the higher Quadrumana. 



