DE. J. CLELANOD ON THE VARIATIONS OE THE HUMAN SKULL. 
151 
To the first of these groups there is scarcely any objection ; for it must be admitted 
that the French skulls examined, with the exception of skull 24, exhibit a certain ap- 
proach to the brachycephalic protile. But in the other groups there are great misplace- 
ments, sufficient to show that the radial measurements are not calculated by themselves 
to exhibit altitude and comparative development of the frontal and occipital regions. 
The key to this may be found on examination of the deviations in position of the post- 
auricular depression as compared with the front of the foramen magnum. Thus the 
Kafir skulls exceed the French in height both actual and as compared with length, yet 
the radial measurements would lead to a contrary supposition ; and the explanation is 
that in the Kafir the postauricular depression is one-fifth of an inch more elevated above 
the foramen magnum than it is in the French. So also the low-skulled Germans are 
associated with the rather high-skulled Greeks by the ear being a quarter of an inch 
lower in the German. The Maori and Greek are placed in opposition, the Maori 
seeming to have the anterior part of the arch weakly developed, and the Greek the pos- 
terior part weakly developed, but the postauricular depression is placed more than a 
fifth of an inch further forwards in the Maori than in the Greeks. 
The circumstances which regulate the level of the postauricular depression as com- 
pared with the front of the foramen magnum are various. Yielding of the base, so as 
to make it transversely flat or concave as viewed from the exterior, obviously causes de- 
scent of the ear. Thus the gravitation changes of advancing years depress it, and the 
European skulls, with the exception of the Scotch, have it low, apparently because the 
base is not so massive and resisting as in races which have the base-line longer. 
Levelness of base-line is accompanied with a low ear, as in the French and German 
female skulls 25 and 34. Partly from this cause, and probably partly from slenderness of 
base, the ear is lower in the female than the male. The Germans have the ear parti- 
cularly low, partly from slenderness of base, and partly, as may be supposed, from breadth ; 
for growth of the lateral part of the brain will not only press outwards the lateral wall 
of the cranium but will depress its inferior limit. In all this there is evidence of what 
has been already suggested, that yielding from pressure is not a phenomenon confined 
to elderly skulls. Pressure is continually acting on the cranium, and produces most 
effect when the bones are least capable of resistance, precisely as has been shown by 
Exgel* to be the case with the bones of the face. 
The variations of the position of the postforaminal depression backwards and forwards 
are more difficult to explain ; but it is evident that this point corresponds very nearly 
with the outer extremity of the upper border of the pars petrosa, which limits poste- 
riorly the middle fossa of the base of the skull ; therefore the further back it is it indi- 
cates the greater elongation of the temporo-sphenoidal lobe and the portion of the brain 
above it, with corresponding shortening of the occipital lobe and cerebellum. 
Seeing that radial measurements extending to the roof of the skull are vitiated as an 
indication of height by the variable elevation of the ear above the base, probably the 
* Das Knochengeriiste ties menschlichen Antlitzes : Vienna, 1850. 
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