124 MAMMALIAN DENTITION 



Arabian Baboon, the dentition of which is presented in Fig. 

 43, feeds solely upon roots and berries. The pronounced elon- 

 gation of the jaws which has plainly occurred after the pre- 

 molars had become reduced in number gives the animal a dog- 

 like appearance and has resulted in actual convergence back- 

 ward of the limbs of the dental arch. In the mandible the 

 interdental space is very narrow, the symphysial region being 

 largely filled up with bone. Sloping incisors, enormous ca- 



Fig. 43. — Dentition of Arabian Baboon (Papio hamadryas arabicus, Thomas; 

 9.823-5). Example of a purely herbivorous Primate dentition. Compare the molars 

 in this figure with those of the Pig (Fig. 72). Note the secondary elongation of all 

 the molars but especially of the lower third. 



nines and a typical Primate sectorial first lower premolar are 

 again obvious, the last-mentioned being especially well marked. 

 The molars are strikingly developed ; they increase in size from 

 first to third in both jaws and the transverse ridges joining 

 the high nipple-shaped cusps are very pronounced. The last 

 lower molar is considerably lengthened by the occurrence upon 

 its talonid of a large hypoconulid. Altogether the dentition of 



