RECONSTRUCTION OV TROGLODYTES NICER 



6ii 



Shortly afur Uk- appcarancf ol this midair mass tlu- nucleus of Col! 

 begins to diminish. 1 lir tliminution ol this nuclear mass contimu's ra])idly 

 until the I'ntire column with its nucleus disappears. 



FIG. 2-2. \ EN rKAL SURFACE OF GRAY MATTER Ol- BRAIN STEM, 

 TROGLODYTES NIGER. 



Key to Diagram, int. oli\ i , InlVrinr Olive; i ai. cin. body, Lateral Geniculate Body; meso-cen. body, 

 Mesial Geniculate Body; I'ontile, Pontile Nuclei; v. cii. and \e\t. cochi.., Ventral CochUar Nucleus; v. 

 GR. COL. and vent, gray coi.., Ventral Gray Column. 



The nucleus of Burdach reaches its maximum at the le\el of disappear- 

 ance' of the nucleus ol Coll. It then <^raduall\ diminishes and comes to an end 

 below the mid-\ entncular \v\v\. 



The substantia gelatmosa trigeniini described in connection with the 

 high cervical le\cl ol the spinal coicl yraduallx passes more Into the latero- 

 meridianai position, which is charaett'ristic ol this structure. 1 laving reached 

 this [)osition it continms upward almost unchanged to the upper icxel ol tlie 

 pontile portion of the stem where it linallN becomes e.xpanded as the convolu- 

 t lones c|uinti. 



