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ANATOMY OF THE CENTRAL NERVOUS SYSTEM. 



So long as we are unable correctly to name all of these fibers according to 

 their function, it will be advantageous, for the sake of clearness, — e.g., in 

 investigations in pathology, — to introduce provisional names for them. 



Let us distinguish (1) the radii, medullary rays; (2) the interradial 

 net-work, consisting mostly of fibers running parallel with the surface; (3) 

 the superradial net-work, and (4) the tangential fibers. Along the boundary 

 between the superradial and the interradial net-works, the latter becomes 

 greatly thickened. This layer, everywhere visible to the naked eye as a 

 white line, is so much thicker in the region of the cuneus that it is there 





Fig. 153. — Three sections through the cortex of the anterior central gyrus. 

 A, From a child 1 V4 years old. B, From a man 36 years old. C, From a man 

 of 53 years. Myelin staining. Controls have shown that the differences are 

 essentially occasioned by the age. Yet the possibility that a different amount of 

 use of the cortical region under discussion may have added in some degree to 

 the difference cannot be overlooked. (After Kaes.) 



very easily recognized. It is designated as the line of Gennari, or after its 

 later describers as the line of Baillarger, or the line of Vicq d'Azyr (in the 

 cuneus particularly). In the occipital lobe, however, the line lies somewhat 



