1932] Poliak: Afferent Fiber System.^, Primate Cerebral Cortex 



283 



Fig 78, Experiment VII. In this experiment the lesions (L) are confined 

 to the precentral convolution (CA) all the rest of the hemisphere remaining 

 unimpaired. Besides numerous association and callosal fibers many corticofugal 

 fibers degenerated. They are: numerous fine fibers descending from Brodmann 's 

 field 6, numerous coarse fibers descending from Brodmann 's field 4 (pyramidal 

 fibers of the precentral "motor" area); numerous fine efferent fibers entermg 

 the caudate nucleus (NC) and the stratum subcallosum, numerous medium 

 sized fibers reaching the upper comer of the globus pallidus (Gp), the number 

 of the latter being hardly less than that of the pyramidal fibers; a con- 

 siderable number of fairly coarse fibers reaches the stratum intermedium 

 of the peduncle, the substantia nigra and the reticulate substance of the mid- 

 brain, ventral tegmental field and dorsal pontine nuclei. (Compare Experi- 

 ment VIII, figs. 80-84, and my paper, 1928.) None of the pyramidal fibers 

 decussates in the corpus callosum to reach in this way the opposite peduncle. 

 The pyramidal tract forms the middle third of the peduncle of the same side. 

 Internal capsule (C'i), Sylvian fossa (FS), globus pallidus (Gp) , putamen (Put). 



