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INTRODUCTION TO NEUROLOGY 



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Fig. 135. 



Figs. 134. 135. Lateral and median views of the human cerebral hemi- 

 sphere, to illustrate the sequence of maturity of the myelinated fibers of 

 the cortex during the development of the brain, according to Flechsig's 

 observations. The numbers indicate approximately the order in which 

 different parts of the cortex acquire their mature fibers. Areas 1-12 

 (double cross-hatched) constitute the primordial region, made up chiefly 

 of the projection centers; these include the olfactory area (1, 3, 4, and 4a), 



