THE STRUCTURE OF THE BRAIN STEM 



411 



<nza.Pi- 



AMMOCCKTES 



TELEOSTEA 



i AMPHIBIA 





PT 



REPTILIA 



CB 



MAMMALIA 



FIG. 181. Diagrammatic view of the brain in different classes of vertebrates. 



(GASKELL.) 



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

 striatum ; GHR, right ganglion habenulse ; I, olfactory ; n, optic nerves. 



