GROWTH OF THE CEREBRAL CORTEX 



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TABLE 12 

 Showing the thickness of the cerebral cortex according to sex, within each brain 

 weight group. Data taken from tables 6, 7, and 8. The average thickness of the 

 sagittal and frontal sections and that of the horizontal section are separately given, 

 with the average brain weight for each brain weight group examined 



some excesses in favor of male. Groups XIV, XVI and XVII on 

 the horizontal sections also show some excesses in favor of female. 

 These differences, however, lie within the limits of individual 

 variation, and hardly can be regarded as suggesting a difference 

 in cortical thickness due to sex. Therefore, I conclude that 

 there exists no sex difference in cortical thickness when brains 

 of like weights are compared. But, if either body weight or 

 body length are taken as the standard for comparison, a sex dif- 

 ference in cortical thickness appears in favor of male, because 

 the brain weights under such conditions are higher in the males 

 than in the females. 



