TO RELATIVE CAPACITY OP RACES. ^15 



ihat the highest average weights of brain in both sexes occur not 

 later than twenty years of age, it appears a more legitimate inference 

 to trace to exceptional cerebral development towards the period of 

 adolescence, the mortality which rendered available so many exam- 

 ples of unusually large or heavy brains, than to assume that the 

 normal healthy brain begins to diminish at that age. 



It is a fact familiar to popular observation that a large head in 

 youth is apt to be unfavourable to life. A tendency to epilepsy 

 appears to be the frequent concomitant of an unusually large brain ; 

 and with the congestion accompanying its abnormal condition, this 

 may account for the weights of such diseased brains as have been 

 repeatedly found in excess of nearly all the recorded examples of 

 megalocephaly in the cases of distinguished men. But a greater 

 interest attaches to a remarkable example of healthy megalocephaly 

 Tecorded in the British Medical Journal for 1872. The case was 

 that of a boy thirteenyears of age, who died in Middlesex Hospital 

 from injuries caused by a fall from an omnibus. His brain was found 

 to weigh 58 oz. He had been a particulaity healthy lad, without any 

 evidence of rachitis, and very intelligent. This is a strikingly excep- 

 tional case of a healthy brain, at the age of thirteen, exceeding in 

 weight all but two of the greatest ascertained brain-weights of dis- 

 tinguished men. 



From the evidence already adduced of relative cubical capacity of 

 the skulls of different races, it appears, as was to be expected, that 

 there is a greater prevalence of the amply-developed brain among the 

 higher and more civilized races. But all averages are apt to be 

 deceptive; and the progressive scale from the smallest up to the 

 greatest mass of brain is by no means in the precise ratio of an intel- 

 lectual scale of progression. The results of Dr. J. B. Davis's investi- 

 gations, based on the study of a large, and in many cases a seemingly 

 adequate number of skulls, bring out this remarkable fact, that, so 

 far from the Polynesians occupying a rank in the lowest scale, as 

 afl&rmed by Professor Yogt, the Oceanic races of the Pacific generally 

 rank in internal capacity of skull, and consequent size of brain, next 

 to the European. 



But it is of more importance for our present enquiry to note that, 

 as exceptionally large and heavy brains occur among the most civilized 

 races, in some cases — and in some only, — accompanied with corres- 

 ponding manifestations of unusual intellectual power: so also it 



