ARCHITECTURAL CHANGES DUE TO GROWTH. 



.245 



YEARS, 10 



30 



50 



60 



70 



30- 



20 

 10 

 0, 



F.3s. 



YEARS.IO 



10 



FlG. 49. Charts C, D, E. Showing the increase in the medullated 

 fibres in the three layers during the growing period, and the 

 decrease in advanced age. Birth, to 79 years (modified from 

 Vulpius). C, third frontal gyrus, left side ; D, anterior cen- 

 tral gyrus, right side; E, first temporal gyrus, left side. 

 , outer layer ; , middle layer ; . . . ., inner layer. 



