1932] Poliak: Afferent Fiber Systems, Frimate Cerebral Cortex 39 



degenerate, is identical with the posterior or the caudal segment or 

 "fan" of the thalamo-cortical radiation originating in the caudal 

 thalamic segment and supplying the caudal half of the somato-sensory 

 cortex behind the central sulcus (shaded areas in fig. 3). Bundles of 

 the radiation remaining normal are those springing from the oral or 



FcaLc 



Fig. 3, Experiment III. External (upper figure) and internal (lower figure) 

 face of the monkey's hemisphere showing the location and extent of the two 

 projection regions of the cerebral cortex found in this experiment (shaded 

 areas). Somatic sensory region behind the central sulcus (C) and above the 

 fornicate sulcus (Fc) ; visual area in the upper lip of the horizontal branch of the 

 calearine fissure (Fcalc) and in front of the ascending branch of that fissure. 

 Differently shaded areas indicate difference in number of afferent fibers. Small 

 dotted area in the posterior portion of the temporal lobe represents the super- 

 ficial lesion through which the knife was introduced into the substance of the 

 hemisphere. Sylvian sulcus (FS). (Compare figs. 66-74.) 



rostral portion of the thalamus and supplying the oral half of the 

 somato-sensory cortex in front of the central sulcus. The degenerated 

 portion of the thalamo-cortical radiation in great part enters the 

 postcentral convolution and its caudal continuation which is the supe- 

 rior parietal convolution (figs. 66-69, 71). Only a few scattered 



