1899.] 



BRAIN OF THE GORILLA. 



69 



some importance. The Y-sliapecl fissure was visible on the mesial 

 surface, and between the fvrks of the Y ex-tended doiun for a short 

 distance from the upper surface of the brain a fissure. Tha 

 arrangement, in fact, is closely like that figured by Benham in 

 figs. 24 and 29 of his paper. I shall follow him in terming the 

 short middle fissure the lateral parieto- occipital and the Y-shaped 



Kg. 3. 



Braiu of Gorilla belonging to the University of Oxford. Dorsal view. 

 Op. Operculum. Other letters as in flg. 1. 



fissure the mesial parieto-occipital. I have used the expression 

 " apparent difference " to distinguish this hemisphere from that 

 in which the sum tofal of the parieto-occipital fissures was 

 represented by one Y for a good reason. When the furrow of 

 that hemisphere is explored by pushing aside its margin a median 



