( i^- : 



the corpus geniculatum externum of the same side had lost almost 

 all its cells in the frontal third only ^), whereas in the corpus quadri- 

 geminnm anticum a slight loss of nerve fibres in the superficial 

 layer was visible. 



The ventriculus lateralis has been drawn in a dorsal direction by 

 the degeneration of the callosum fibres and the softening in the gyr. 

 splenialis. 



The tapetum, which in the human brain consists, at least, partially, 

 of callosal fibres, shows but few degenerated fibres. The great 

 majority of commissural fibres remain dorsally to the occipital strata 

 and spread into the dorsal (mesial and lateral) cortex ; a few pass 

 the sagittal strata in a more or less oblique direction and may run 

 for a certain distance in the area of the tapetum. This latter is 

 almost exclusively formed by the fasc. subcallosus (Muratoef), sub- 

 stance grise subependymal re (ükjérine). 



For cell alterations the right hemisphere was used, the cortex of 

 which had not been injured ai all. The parafïine blocks were cut 

 in sections of 10»/ and stained with toluidin blue. 



lat 



Foto 1. 2 



Folo 3, 4, Ü 



Fig. la. 



Figure i represents a section through the cortex of the gyr. splenialis 

 of a normal cat; the exact situation is to be seen on diagram la. 

 The photo shows a typical lamination of the so-called visuo-sensory 

 zone (area striata), characterised by the absence of the lamina 



1) I do not insist in this paper on this statement, which is doubtlessly of im- 

 portance for our knowledge of visual localization, and which agrees, in principle, 

 with some of von Monakow's fundamental observations. 



