6 MUSEUM BULLETIN NO. 9. 



skulls of these people is, therefore, further evidence of the 

 activity and extensive movements of their mandibles during 

 the process of mastication. Lastly, the coronoid process is 

 low and very stout, and its distance from the condyle renders 

 the leverage of the temporal muscle on the mandible still more 

 effective. 1 



Dr. Ales Hrdlicka 2 remarks upon the great development 

 of the jaw muscles in the skulls of the Eskimo, with especial 

 reference to the size and strength of the temporal muscles and 

 their probable effect upon the shape of the skull. He also notes 

 the great breadth of the ascending ramus of the mandible, strong 

 coronoid process, and, in certain of the lower jaws examined 

 by him, "remarkable individual variations, due to a great 

 development and activity of the masseter muscles." From 

 this very instructive paper I will quote the following paragraph 

 (page 211), as it is of exceptional interest in the present 

 connexion : 



"The lower jaw presents a moderate to fairly prominent, 

 and not rarely square chin, medium height, very strong build, 

 and broad ascending branches. A marked and general feature 

 is a pronounced bony reinforcement of the alveolar arch extend- 

 ing above the mylo-hyoid line from the canines or first bicuspids 

 to or near the last molars. This physiological hyperostosis 

 presents a more or less irregular surface and is undoubtedly 

 of functional origin, the result of extraordinary pressure along 

 the line of teeth most concerned in chewing, yet its occurrence 

 in infant skulls indicates that at least to some extent the feature 

 is already hereditary in these Eskimos." 



When we turn to the shape of the palate we find still more 

 evidence, both as to the severe nature of the work which the 

 jaws are called upon to perform, and also the chewing method 

 which has evidently been of most service in its accomplishment. 



1 See "A consideration of some of the more important factors concerned 

 in the production of man's cranial form," by Prof. A. Thomson, Journ. Anthr. 

 Inst., 1903. 



2 See "Contribution to the Anthropology of Central and Smith Sound 

 Eskimo," American Museum of Natural History, Vol. 5, Pt. 2. (Anthro- 

 pological paper). 



