THE CEREBRAL CORTEX 



613 



types: those whose axons enter the projection paths, and those whose 

 axons enter the association paths; also that while these cells intermingle 

 with each other in all portions of the cortex, yet certain areas are char- 

 acterized by an undue proportion of one or the other type, and may 

 accordingly be considered as 

 either projection centers or as- 

 sociation centers. 



The larger cells belong, as 

 a rule, to the projection centers, 

 and the peculiar type of large 

 cell contained in a given center 

 may often be considered as 

 characteristic of that particular 

 area. Thus the motor area con- 

 tains giant pyramidal cells 

 (Betz cells), and the visual area 

 the giant 'solitary cells' of 

 Mevnert. 



> 



The larger cells, being of 

 Golgi's Type I, are assumed to 

 be connected with the projec- 

 tion fibers. On the other hand, 

 the smaller cells granule cells, 

 polymorphous cells, etc. which 

 more frequently belong to 

 Golgi's Type II, are thought to 

 supply the axons of association 

 paths. Those large areas- 

 parietal lobe, frontal lobe, 

 lobulus insulae which consist 



in so large a part of the smaller type of cells, may therefore be supposjd 

 to contain the larger association centers. 



The cells in any given portion of the cortex are not only arranged in 

 layers parallel to the surface of the cerebral convolutions, but the 

 passage of fibers of the medulla to or from their terminations within 

 the pallium, also separates the cells of the cortex into irregular rows 

 or striatious, whose axis is perpendicular to the surface of the con- 

 volutions. 



FIG. 529. LARGE PYRAMIDAL CELL OF THE 

 CORTEX. 



(After W. von Bechterew.) 

 "The Nervous System.") 



(Barker, 



