Thompson, Medullaiion of Cortical Fibers. 371 



time on the II and III Meynert layer of the child measured 

 about the same as, or a little less than, the adult/ In fact the 

 most significant growth process in the later periods was stated 

 to be the increase in the thickness of the II and III Meynert 

 layer due to the addition of new medullated fibers. In the 

 description of the cortex of the child, Kaes states that the oc- 

 cipital region and possibly also the central region have reached 

 the stage of development in which the boundary line between 

 the II and III Meynert layer and the outer association layer is 

 fixed by the medullation of the Baillarger and Gennari layers.' 



At these points, therefore, we should expect to find that 

 the II and III Meynert layer of the child measures a little less 

 than that of the youth or adult. But the tables of measure- 

 ments for the child cortex give a thickness for the II and III 

 Meynert layer of these regions which is more than twice as 

 great as that of the youth or adult. ^ No attempt is made to 

 reconcile this discrepancy between the tables and the descriptive 

 statements, nor is any process mentioned which could account 

 for a thinning of the II and III Meynert layer subsequent to 

 the appearance of the Baillarger and Gennari layers. 



The comparison of the Chinese and Hindu brains with the 

 German revealed no very marked differences of fiber stratification. 

 The general impression gained from the preparations was that in 

 the Asiatic brains, the fibers are coarse and less numerous, while 

 in the German brains they are fine and more numerous.* The 

 measurements showed that both the Hindu and the Chinaman 

 were below the Germans in their development. The difference 

 was most marked in the case of the Hindu. ^ His brain had a 

 medullary center which was narrower than that of the German, 

 and a cortex which was broader. In both these respects the 

 Hindu brain resembled that of the child, rather than that of the 



' 5> p. 33. 



* S. P- 35-37- 



» S, p. 36 table. 

 ' 6, p. 14. 



* 6, p. 10-14, 



