THE HUMAN DENTITION 137 



certain quite primitive and generalized features. Whether the 

 individual existed during the first or the second interglacial 

 phase is disputed. But from mammalian remains in the same 

 and in contemporaneous deposits we infer that the country in 

 ■which he lived was well forested and possessed a relatively 

 moist climate. 



The mandible is extraordinarily massive and although it is 

 considerably longer than any mandible of today it is not 

 really much longer in the dental arch than many modern jaws. 

 The unusual length is due to the marked breadth of the ramus. 



Fig. 49. — Occlusal view of the Heidelberg mandible (F. 3, W.R.U. ; from cast by 

 Krantz). This cast has been broken at the symphysis and in the right ramus. Note 

 the cruciform pattern of furrows on the molar teeth and the angle between the long 

 axes of the first and second molars, both features distinctively human. 



Ill the great vertical depth of the body, the breadth of the 

 ramus, the form of the symphysial region, the absence of an 

 "ape-shelf" and the occurrence of merely a moderate amount 

 of bony tissue encroaching upon the anterior part of the 

 tongue space, the Heidelberg mandible displays ancestral fea- 

 tures reminiscent of Propliopithecus. The masseter and inter- 

 nal pterygoid must have been the most powerful masticatory 

 muscles ; the area for attachment of the temporal indicates that 

 it was not disproportionately large for the massive skull. 

 Similar features are to be noted in Propliopithecus. The 



