Correlation oj Brain CapacUij and / ntcUigcnce. 231 



From the measureiuents^f licads ami brains no very extensive 

 conclusions as to mental activity can be drawn. 



High intelligence is most fre(|Uently I'imukI in cases witli average 

 head measurements. 



Kxce})tionally large liead measurements, ns also exceptionally 

 high hi-aiu weights, occasionally pdiiit to gi'cat intelligence, and 

 in the same way exceptionally small head measurements may indi- 

 cate an especially inferior intellect. 



The greatest head measurements and tin- heaviest brain weights 

 are found fairly uniforndy in ))oth highly intelligent and less 

 intelligent persons. 



The -very smallest head measurements, apart from family or other 

 peculiarities, occur in the mentally less functionally capable. 



Pearl (6), in a ])aper not available t(^ us in Melbourne, applies to 

 the above statistical series of Eyerich and L<)\venfeld, Pearson's 

 correlation methods, and deduces therefi'om that a perceptible but 

 vei'v slight ])ositive cm-relation between head size (cii-cumference) 

 and intelligence exists, but warns us from drawing further conclu- 

 jiions or generalisations therefrom. 



Buschan (7) supports the view that there is some correlation 

 between gi-eat skull cajjacity or great brain weight and marked 

 mental ability. In support of this he jioints out, amongst other 

 things, that of the highest professional classes 57 })ei- cent, will have 

 a brain weight of over 1400 gr., and of the lowest classes only some 

 2G per cent, will possess a corresponding brain weight. 



In children, Lee, Lewenz and Pearson (8) conclude " that there 

 is no marked con-elation between intelligence and the size and 

 shape of the head. " 



Lee (D) in the course of an important paper, states "that there 

 is no marked correlation between skull capacity and intellectual 

 ])ower in the case of either sex alone." And. again, " it would not 

 appear from the above resvdts that skull capacity at any rate is a 

 character closely correlated with intellectual ability in the indivi- 

 <lual. and therefoj-e it is rniite eoiieeivably not correlated with 

 )a(-ial al)ilitv." 



In this same paper Miss Lee (-ommits heiself to the following 

 statement : — " Personally I am inclined to hold with Professor 

 Peai'son that the complexity of the convolutions of the brain, and 

 variety of its commissures, rathei- than its uclual size, are the 

 chai-acters we might expect to dift'ei-eiit iate race from laee, and sex 

 from sex, and to have developed with man's civilisation." 



In 1902 Pearson (10), dealing with " upwai'ds of a thousand 

 Cambridge undergraduates," states that " so far as the Cambridge 

 results go, there is no marked correlation between ability and the 



