NATIONAL CHARACTERISTICS OF SKULLS. 221 



head ; equally valuable evidence is afforded by the one as 

 the other. The conclusions which I draw from these facts 

 are briefly as follows. 



It is highly probable that when the struggle for exist- 

 ence was less keen than at present, and the human brain 

 was in consequence less prone to rapid growth, human 

 skulls preserved a pretty uniform type : thus, e.g., all the 

 Neolithic skulls yet discovered are, I believe, dolicho- 

 cephalic, and bear a very close resemblance to each other ; 

 further observation, moreover, shows that the skulls of 

 prehistoric man are unusually bilaterally symmetrical. 

 (Of the Palaeolithic skulls I do not speak, as Ave have 

 not a sufficient number for forming a correct opinion.) 

 It is quite in accordance with the doctrine of evolution 

 to suppose that different environments (such as differ- 

 ences in climate, soil, mode of livelihood, e.g. living 

 by the chase or by agriculture) would produce certain 

 and definite cranial changes ; hence would arise national 

 types of skull, slow in arriving at the degree of differ- 

 ence which exists between an Eskimo and a Negro, slow 

 to change from that type when once acquired. After a 

 time the modifying influence of civilization would come 

 into operation ; and we should a priori expect to find that 

 the wide difference in the environments of individuals, 

 which results from the various existing grades of society, 

 would tend to produce a divergence in the forms of a 

 nation's crania. We are able inductively to verify this 

 deduction. Europe is a field where people are subjected 

 to widely different environments ; and it is precisely in 

 Europe that we observe the hard and fast lines which 

 Ketzius made between the skulls of two nations fade 

 away and cease to mark one type from another. A simi- 

 larity of external circumstances and an absence of marriage 

 with other nations will tend to produce but one type of 

 skull; a difference in external circumstances, and inter- 



