THE STRUCTURE OF THE BRAIN STEM 





CB 



AMMOCCETES 



PN 





TELEOSTKA 



AMPHIBIA 



CB 



REPTILIA 



CB 



MAMMALIA 



FIG. 180. Diagrammatic view of the brain in different classes of vertebrates. 



(GASKELL.) 



CB, cerebellum- PT, pituitary body ; PN,pinea body; C.STR, corpus - 

 GHR, right ganglion habenulse ; i, olfactory ; n, opti< 



