DR. J. CLELAND ON TIIE VARIATIONS OE THE HUMAN SKULL. 
165 
undergone no increase ; but the elongation of the inferior part of the skull is due to the 
length of the occipital hone from the foramen magnum to the tuberosity. Hence the 
proportion of the arch to the base-line exceeds even what is usually found in infancy or 
childhood, being 3'3. The orbito-frontal angle is large and the midfrontal small, the 
postforaminal angle large, and the angle of the tuberosity small, so that the combination is 
produced, not otherwise occurring, of a vertical forehead with prominent eminences going 
together with the rounded and full appearance given behind by a low-placed tuberosity. 
It may further be observed that the enlargement of the arch has taken place princi- 
pally in the frontal and occipital regions, the parietal remaining of a normal length. 
Now in the growth from infancy, the frontal and occipital regions normally increase in 
length as compared with the parietal. If, then, further researches should show that in 
unusually large skulls the parietal is generally less enlarged than the frontal and occipital 
regions, we shall have evidence that the excessive development of the arch takes place 
by a continuance of the method of growth by which the latest steps of its ordinary 
growth are effected. 
The Greek skull 46, already alluded to as having some peculiarities, appears to he an 
instance of Kephalon less marked and of a different kind. It is true that this skull is 
not singular in its size, when compared with all the other skulls in the list ; it is, how- 
ever, the largest of the five Greek skulls, and bears evidence of its shape being altered 
from the national model by continued enlargement. The profile diagram has a much 
more dolichocephalous appearance than those of the other Greek skulls, and one might 
be disposed to doubt the alleged nationality ; but such a doubt does not explain the 
peculiarities, namely, the small cranial curvature, the long base-line, and the large orbito- 
frontal angle. All the peculiarities, however, are removed and the shape of the cra- 
nium assimilated to that of the other Greek skulls if we suppose the frontal portion of 
the arch to be rotated downwards round the fronto-parietal point, so as to lessen the 
fronto-parietal angle, shorten the base-line, push back the line of orbital length, and 
throw the foramino-optic line into a more nearly vertical position. This seems to show 
that this skull presents an instance of individual enlargement accomplished by flattening 
out of the fronto-parietal angle, the result of elongation of the base-line in consequence 
of continued levelness of base, the growing brain having pressed too much downwards 
to admit of the usual contraction of the orbito-basilar angle in process of growth. The 
enlargement of the skull in this instance is produced less by any unusual increase of 
size of the bones than by their being placed at unusual angles one to another. 
Hunchback (skull 93). — This skull exhibits arrest of development in various respects, 
while in others it is fully grown. There is no deficiency in the face nor in the regions 
of the base ; but the frontal part of the arch is short, and, consequent on this, the deep 
frontal angle is small and the cranial curvature deficient. Also the midparietal angle 
is more acute than is usual in adults. These peculiarities, so far as one may judge from 
external appearances, seem to be yery usual among rachitic dwarfs, and not the mere 
idiosyncrasies of this one skull. 
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