THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 
3 
of the glenoid cavity ; he writes: “The form of the glenoid cavity 
.... bears an intimate relation to the dentition of the animal 
and the nature and extent of the movement of the jaws. Thus 
in a child it is nearly flat with no well marked surrounding ele- 
vations, its axis is transverse and little rotary motion is made 
use of. In the adult it is deeply sunk, the axis of the condyle 
is oblique and rotary movements are largely made use of in 
triturating food. In the felidae it is strictly transverse, their 
teeth adapted for slicing but not grinding, would gain nothing 
by lateral motion, which is rendered quite impossible by the 
manner in which the long transverse condyles are locked into the 
glenoid cavity by strong processes in front and behind . . in 
Herbivora the condyle is roundish, the ascending ramus long, 
the pterygoid muscles large and the glenoid cavity shallow. 
In the whale, which of course does not masticate at all . . the 
articulation is reduced to a mere ligamentous attachment.” 
Here, then, I think we have the key to our problem, and that 
we shall find that it is to some differences in the method and ex- 
tent of mastication that is due the distinction in the form of the 
glenoid fossae between civilized and primitive man. Since, 
therefore, in the Eskimo we have a race which seems most 
uniform in the display of glenoid flattening, we will take them 
as the champions of the “shallow-glenoid” type, and examine, 
first, the conditions of their life and the nature of the food they 
have to masticate, and, secondly, the form of the masticatory 
apparatus presented in their skulls. 
Now it is well known that the staple diet of the Eskimo is 
of a more or less purely animal nature, fish, flesh, and fowl being 
their main means of subsistence, while, to judge from all accounts, 
much of the meat they eat must be of a very tough nature; 
so that, on the whole, we could not find any other race of the pres- 
ent day in which there would be so much need for strong jaws, 
and so much need too to use them in such a manner that their 
food should be thoroughly triturated before being swallowed. 
A few extracts from the writings of authors who have lived 
among and studied the Eskimos will perhaps be of use to em- 
phasize my point, and give confirmation to my statement as 
to the nature of the Eskimo’s food. 
