STRUCTURAL ARRANGEMENTS OP CEREBRUM 419 



supra-callosal convolution above, and the hippocampal convolution and the 

 uncus below. The chief fissures separating these are the Sylvian fissure, t 



A 



Forebrain 



yel f 



Corre* 



N. opt. 



eye 



Occipital cortex 



Cerebellum 



FIG. 211. Diagrams from Monakow, showing the evolution of the neopallium, 

 and the gradual shifting of the visual sensory tracts from the mid- brain to the fore- 

 brain, and thence to the occipital cortex. 



A, a bony fish. B, brain of a lizard. C, brain of a mammal (cat). 



central sulcus or fissure of Rolando, the parieto-occipital fissure, the 

 calcarine fissure, the collateral fissure, and the calloso- marginal fissure. 

 Each of the main lobes (or gyri) mentioned above is further subdivided 



