PARIETAL REGION IN THE PRIMATE BRAIN 



335 



Depending on the position of the sulcus, whether near the mesial 

 or lateral border or as in this case intermediate, the position 

 of other furrows will vary, particularly the paramesial above, 

 and which may be on the mesial surface, and the inferior occipi- 

 tal which may be in part on the tentorial surface. The position 

 of the lunate is primarily determined by the relative development 

 of the areas in front and by the extent of striate cortex. These 



superior -parietal 



interparietal 



S interm. prim 

 S. angularis, 



S. interm. sec. 

 parieto-occipital 

 paroccipital 



anterior-occipital 



transverse-occipital 

 paramesial 



lateral calcarine 



inferior occipital temporo-parietal 



prelunate 



Fig. 18 Right hemisphere of a Soudanese negress. 



factors may be such that the lunate is crowded far back, or may 

 fail to develop or assume varying forms or be divided by a gyrus 

 translunatus. With the shifting of the area striata there is asso- 

 ciated a corresponding shifting of the furrows about it. 



The prelunate or lateral occipital is best shown on the left 

 side. From the changes in the areas above and below the forward 

 projection of peristriate area of which this sulcus is an axial fold- 



