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THE NERVOUS SYSTEM 



sociation and commissural fibers from other parts of the cortex. Many of these 

 fibers end in the most superficial stratum of the cortex, the plexiform layer, where 

 the terminal branches of the apical dendrites of the pyramidal cells are widely 

 expanded (Fig. 214). Others terminate as indicated in Fig. 213, where they 



Fig. 213. From the anterior central gyrus of 

 the human cerebral cortex, showing the terminations 

 of corticipetal fibers: a, b, Afferent fibers; B, dense 

 network produced by the terminal branches of such 

 fibers. Golgi method. (Cajal.) 



Fig. 214. Nerve-cells and neuroglia 

 from the cerebral cortex: A, Neuroglia; B, 

 horizontal cells of Cajal ; C, pyramidal cells; 

 D, cell of Martinotti; E, stellate cell. 



are seen forming a close network of unmyelinated fibers. Enmeshed in the 

 dense fiber plexus indicated at B, Fig. 213, are the pyramidal cells illustrated 

 in Layer III of Fig. 215. 



The nerve-cells of the cortex are disposed in fairly definite layers as indicated 

 in Fig. 215. We may enumerate five well-recognized varieties: (1) the pyra- 



