316 G. G. Mac Curdy — Significance of the Piltdown Skull. 



broad with a marked flatness on top, and the mastoid processes 

 are relatively small. 



The lower jaw is, in some respects, more primitive than the 

 cranium. The horizontal ramus is rather slender, resembling 

 in shape that of a young chimpanzee, especially in the region 

 of the symphysis. Only two teeth, the first and second molars, 

 were found, and these were in their sockets. They are typi- 



FlG. 1. 



Fig. 2. 



Feg. 3. 



Fig. 4. 



Fig. 1. 

 Fig. 3. 



Heidelberg man. 

 Modern man. 



Fig. 2. 

 Fig. 4. 



Chimpanzee. 

 The Sussex jaw. 



A, Articular process or condyle (broken in the Sussex lower jaw). S, Sig- 

 moid notch, c, Canine tooth. 1, 2, 3, First, second, and third molars. 

 From a sketch by Sir Kay Lankester in The Daily Telegraph. 



cally human although relatively of large size and narrow, thus 

 requiring more linear space for their setting in the jaw. Each 

 has a fifth cusp. The crowns are worn flat by mastication, 

 indicating that the canines were not so prominent as to inter- 

 fere with essentially human processes of trituration, also that 

 the individual was of adult age. The ascending ramus is 

 unusually broad and the sigmoid notch at the top in front of 

 the articular process is shallow. In these respects, the Sussex 

 lower jaw approaches that found near Heidelberg. The feeble 



