CONTEIBUTIONS TO THE STUDY OF INTERKACIAL 
CORRELATION. 
By E. TSCHEPOURKOWSKY, Moscow. 
Many authors have tried to explain mechanically several of the distinctive 
characters of the races of man, especially the different forms of the skull. I may 
mention Nystrom's hypothesis : he asserted that the head-form may be the product 
of the work of muscles on the one hand, and of the inner pressure of blood on the 
other. We have also similar theories due to Ranke and Thomson, but the evidence 
on which they are based is very slight. I propose in this paper to state some 
considerations based on biometrical methods. In a paper read before the Congress 
of Naturalists and Physicians assembled in St Petersburg in 1900 I made the 
following statements based on the measurements of 700 skulls*. 
(1) The form of the skull is connected with the form of its base, and the variation 
of the first produces a series of the variations in the second, some of which resemble 
embryonic growth. (2) We do not find between the lengths and breadths of skulls 
in the same race a relation which is in accordance with the principle spoken of as 
that of " compensational growth." If one increases, the other also increases. But 
if we pass from one race to another we find that with the growth of length there is 
a decrease of the breadth, and vice versa. This arises from the fact that the most 
brachycephalic races have the greatest breadths and the smallest lengths. The 
effect wcfuld be the same if, instead of different races, we took dolichocephalic and 
brachycephalic groups in the same race. (3) As the decrease of the skull length is 
connected with the decrease of the length of skull-base and of the face-length, we 
should expect that lower races with powerful jaws and small cranial capacity must 
have a tendency to dolichocephaly, and again that the decrease of the facial parts 
and the development of the brain are iufiuences which are favourable to brachy- 
cephaly. (4) In the geographical distribution of the cephalic index we have two 
well-marked regions : generally speaking southern continents are dolichocephalic 
and northern are brachycephalic. We can perhaps distinguish on the earth two 
* Extracted from the Eeport of the Congress. 
