142 University of California Pitblications in Anatomy [Vol. 2 



degenerated : a larg-e zone and a small one. Thus the number of zones 

 in this experiment also ag^rees with the number of lesions. The large 

 zone occupies a,bout the lateral half of the intermediate or macular 

 segment and is found on sections through the posterior third of the 

 lateral geniculate body (marked with an asterisk in 5-8, last row 

 to right). This zone has in more anterior sections a triangular 

 shape with the sharp angle pointing toward the hilus of the nucleus 

 which is, however, reached in most posterior sections only. The small 

 degenerated zone occupies exactly the tip of the lateral geniculate 

 body, and is of triangular shape with the sharp point turned toward 

 the hilus of the nucleus although it does not reach it. This zone is 

 found in the anterior or oral half of the lateral geniculate body 

 (marked with a double cross in 1-4 in the second row from the right, 

 fig. 18). Here, too, both degenerated zones occupy the intermediate 

 or macular segment of the lateral geniculate body, which again agrees 

 with the position of both lesions in the macular cortex over the occipi- 

 tal operculum and in the macular portion of the visual radiation. 

 In particular, the position of the small degenerated zone (double 

 cross) is identical with a portion of the degenerated zone (o) in the 

 left hemisphere, in agreement with the smaller size of its lesion ; 

 while the larger degenerated zone (asterisk) partly corresponds with 

 both small degenerated zones {d and c) in the left hemisphere which 

 agrees with the position of its lesion. 



The general result of both these experiments in the left and right 

 hemisphere is that all of the six degenerated zones are placed in the 

 intermediate segment of the lateral geniculate body where, according 

 to Brouwer and Zeeman's experiments, macular fibers from both 

 retinae terminate. This is in agreement with the fact that all six 

 lesions were located in the macular portion of the striate area or close 

 to it. (Compare Experiment V-b, which is the reverse of the present 

 experiment.) It is also evident that there exists a fair degree of cor- 

 respondence between the number, size, and position of the small degen- 

 erated zones in the lateral geniculate bodj' and in the striate cortex 

 of the corresponding- hemisphere. The conclusion seems to be that 

 each small segment of the lateral geniculate body has its own repre- 

 sentation in the visual projection cortex of the same side, and does 

 not mingle with its neighbors. In other words, there exists a faithful 

 projection of the lateral geniculate body and thus of the hemiretinae 

 upon the striate area, which renders possible a faithful preservation 

 of "figures" in the visual acts. It is also clear that if the macular 



