ANATOMICAL STRUCTURE OF ANTHROPOID APES. 59 



poral bone. The nasal bones are higli, very narrow 

 in their upper part, and widening below. When 

 they are nnited in the centre of the nasal bridge, a 

 s'oping,keel-sliaped projection may often be observed. 

 The inferior turbinated bones of the nasal cavity are 

 remarkable for their size. In the skulls of young 

 animals the inter-maxillary bones, which are in all 

 anthropoids early united with those of the same 

 region, stand up high and peaked between the nasal 

 bones and those of the upper jaw. 



The crowns or prominent external surfaces of the 

 enormous canine teeth project in the centre of the face 

 on either side like pillars, just below the nostrils, and 

 extend above and below the row of teeth in the two 

 upper jaws (see Fig. 16). In this way the crowns of 

 the canine teeth form a retreating triangular space, 

 of which the base-line of the equilateral triangle 

 corresponds with the row of teeth. The chin part 

 of the lower jaw, in a front view, also takes the 

 form of an equilateral triangle. In the latter case 

 the base-line is covered by that section of the row of 

 teeth containing the incisor teeth. The sides of the 

 triangle are covered by the converging canine teeth 

 (see again Fig. 17). The incisor teeth, enclosed 

 between the latter, in tliat part of the lower jaw 

 already described, are retreating. The rami of the 

 lower jaw are high and very wide. The angle of 

 the lower jaw is obtuse (Fig. 15). The front or 

 coronoid process and the back or condyloid process of 

 the ramus of this bone are separated I'rom each 

 other by a deep, hollow cleft. The condyloid process 

 projects abruptly above, but is less marked behind. 



