1932] Poliak: Afferent Fiber Systems, Primate Cerebral Cortex 285 



Fig. 80, Experiment VIII. In this experiment portions of the precentral and 

 frontal cortex and a part of the subjacent white substance of the frontal lobe 

 were destroyed. The lesion (L) remains confined to the cortex and to the nearby 

 white suljstanee with the exception of a single small lesion visible in this 

 figure, the deepest in the series. Besides this, a small cortical injury of the post- 

 central convolution opposite the precentral lesion in figure 81 was found. Beside 

 numerous association and callosal fibers, tlie following efferent fibers degenerated: 

 (1) very numerous and very fine fibers to the head of the caudate nucleus (Nc) 

 and to its stratum zonale and str. subcallosum, (2) others of medium size form- 

 ing the innermost segment of the cerebral peduncle to the stratum intermedium 

 of the peduncle and to the substantia nigra, (3) others to the globus pallidas, 

 and finally (4) the pyramidal fibers. No descending fibers from the precentral 

 and from the convex frontal cortex (from field 4, 6, 8, 9 of Brodmann) enter 

 the red nucleus or the roof of the midbrain. Superior frontal convolution (F^). 

 (Compare with fig. 7 and figs. 81-85, 96.) 



