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University of California Puhlications in Anatomy [Vol. 2 



short and long segments and particles of coarse, as well as of medium 

 sized and fine blackened degenerated fibers can be seen. Many of them 

 have an oblique or a horizontal course running for a considerable 

 distance in the ventral strata, others ascend in a more irregular or 

 even in a straight way upward toward the middle cortical layers. 

 However, hardly any degenerated fibers exist in that cortical area 



Fig. 9, Experiment II. This figure represents a portion of figure 48 at a 

 somewhat higher magnification, demonstrating the relation of the afferent 

 thalamic fibers to the cortex of the sulcus centralis (C). In this experiment the 

 somatic sensory radiation degenerated almost completely. The bulk of the 

 afferent fibers (all details in the figure except the outlines of the cortex repre- 

 sent degenerated fibers) enter as dense bundles into the cortex lining the bottom 

 of the sulcus centralis (C), while the number of fibers decreases toward the con- 

 vexities both of the precentral (CA) and of the postcentral convolution (CP). 

 In the cortex of the bottom of the central sulcus, afferent fibers reach the 

 stripes of Baillarger (dotted, sickle-shaped intracortical stripe) ; a few fine fibers 

 reach even the supragranular layers. This cortical area with the best afferent 

 fiber supply and the best developed granular layer and Baillarger 's stripes 

 is the "nuclear or focal zone" of the entire somatic sensory cortical region 

 of the hemisphere. It corresponds with field 3 of Brodmann. (Compare figs. 6, 7.) 



