THE STRUCTURE OF THE CEREBRAL CORTEX 



269 



of them is shown in Fig. 123 and they are drawn separately in 

 Fig. 125 as they appear in the precentral gyms (gyrus centralis 

 anterior of Fig. 54). These afferent fibers may be either sensory 

 projection fibers or association fibers from other parts of the 



Fig. 123. Diagrammatic illustration of the arrangement of neurons in 

 the cerebral cortex as revealed by the Golgi method. The figure is copied 

 from Obersteiner and the layers are numbered differently than in Brod- 

 mann's scheme, Fig. 127. Obersteiner's layer III includes layers III, IV, 

 and V of Brodmann. The arrows indicate the direction of nervous conduc- 

 tion, and the axons of the neurons are marked by a cross, x ; gl., layer of su- 

 perficial neuroglia cells; m, beginning of the layer of white matter; 12, 13, 

 14, and 15 mark neuroglia (glia) cells; the other numbers designate different 

 types of neurons. 



cortex. The synapses between these incoming fibers and the 

 neurons of the cortex among which they end are of various types. 

 Many of the afferent fibers end in the outermost layer of the 

 cortex (layer 1 of Figs. 123 and 124) among the dendrites of the 



