1898 - 99 .] Dr Hepburn on Improved Form of Craniometer. 609 
skulls the height varied from 132 mm. to 144 mm., giving an 
average height of 1 40 mm. 
The supra-zygomatic segment varied from 109-120 mm., the 
average being 113*9 mm. ; the infra-zygomatic segment varied from 
21-30 mm. Kepresenting the supra-zygomatic segment in the 
terms of a percentage of the entire height, it varied from 78*5-84 
per cent., the average percentage for the group being 81*3 per 
cent., leaving an average of 18*6 per cent, for the infra-zygomatic 
segment. 
(6) Dolichocephali. — In this set the height varied from 128- 
146 mm., giving an average of 135*5 mm. 
The supra-zygomatic segment varied from 98-114 mm., the 
average being 106*1 mm. ; the infra-zygomatic segment varied 
from 22-35 mm., the average being 29*4 mm. Again, reducing 
the supra-zygomatic segment to a percentage of the total height, 
we find that it varied from 74 per cent, to 83*8 per cent., giving an 
average of 78*1 per cent., and leaving an average of 21*8 per cent, 
for the infra-zygomatic segment. 
(c) Anthropoids. — The figures showed a steady reduction of the 
supra-zygomatic segment, with a corresponding increase in the 
infra-zygomatic segment, so that upon the figures referred to, these 
apes formed a sequence from man in the order orang, gorilla, young 
chimpanzee, adult chimpanzee. 
In view of the fact that the segmentation of the basi-bregmatic 
height into supra- and infra-zygomatic segments suggests approxi- 
mately the relative proportions between the height of the cerebrum 
and the height of the cerebellum, the results above referred to are 
extremely interesting, whether considered as averages or per- 
centages. 
In the human skulls whose measurements have been given, the 
average supra-zygomatic height is 113*9 mm. or 81*3 per cent, of 
the total height for the brachycephali, and 106*1 mm. or 78*1 per 
cent, of the total height for the dolichocephali. Approximately, 
therefore, the cerebrum, with the skull-cap, is 7*8 mm. or 3*2 per 
cent, higher in the brachycephali as compared with the dolicho- 
cephali. On the other hand, the infra-zygomatic segment in 
brachycephali has an average of 26 mm. or 18*6 per cent, as com- 
pared with 29*4 mm. or 21*8 percent, in dolichocephali, apparently 
