THE STRUCTURE OF THE BRAIN STEM 



439 



Optic 



-Denf^te Nucleus 



InjWior Olive 



Vest i bub Spinal Tract 



Crossed Pyramidal Tract 



Direct Pyramidal Tract 



D65C6MDING M6RVE 

 TRACTS. 



FIG. 200. Schema of course taken by chief descending tracts of brain stem. (GORDON 

 HOLMES.) The tract in red, to the right of the rubro-spinal tract, includes the 

 posterior longitudinal bundle, together with the fibres of the thalamo-spinal and 

 tecto -spinal tracts. 



