228 



ANATOMY OF THE CENTRAL NERVOUS SYSTEM. 







I- ' , 



4 







1 "1 '" ti%y 



A '-if 



>*■-*« 



\ifj 



i,'-': -' f ° 4 ■ ' '^ <, ' *i> 



-^.'^' Mv ° -i ' ° • ' '" M "M '■ £ 

 .'- '"-'■/' . > '''■-•'' • .° ■ ''•■ '' ■ ' "i 



' h:,' '■;.' • " «■ ''/,•';,*. ° ; „ 



/' =■' "-.."'■.'it® ' ^ ; 



c 



50 



r 



dividual cells are larger 

 and their apical proc- 

 esses longer, the farther 

 the cells lie from the sur- 

 face. The fourth layer 

 of cells, Ij'ing beneath 

 the large pyramids, con- 

 sists again of smaller 

 cells, not uniformly dis- 

 tributed. They are 

 wedged in between the 

 radiating masses of med- 

 uUated fibers passing 

 into the cortex. 



Besides the pyramidal 

 cells mentioned, there is 

 scattered in all layers 

 of the cortex a large 

 quantity of smaller, 

 polygonal cells, the neu- 

 raxons of which split up 

 completely very soon 

 after leaving the cell. 



In Fig. 150 these cells 

 appear as numerous, 

 clear, polygonal struct- 

 ures lying everywhere in 

 the neighborhood of the 

 pyramids. 



In order to become 

 acquainted with the his- 

 tology of the cortex, it is 

 necessary to employ sev- 

 eral methods. Each 

 shows a different pict- 

 iTre, and only by com- 

 bining these is there ob- 

 tained an accurate con- 

 ception of it as a whole. 

 Since a small part only 

 of the cells is visible 

 in Fig. 151 (left side). 



