THE SPINAL CORD 56* 



for the transmission of motor or volitional impulses from the encephalon 

 to the spinal cord. 



FIG. 23 1 . DIAGRAM OF THE PYRAMIDAL TRACT OR MOTOR PATH. III. Common oculo-motor 

 nerve. IV. Pathetic nerve. V. Motor division of the trigeminal nerve. VI. The abducens 

 nerve. VII. Facial nerve. IX. and X. Motor divisions of the glosso-pharyngeal and pneumogas- 

 tric nerves. XI. Spinal accessory nerve. XII. HypoglossaJ nerve. (Van Gehuchten.) 



The pyramidal tracts are also the conductors of the nerve impulses dis- 

 charged by the cells of the cerebrum during the occurrence of the affective 

 or emotional states, that excite to activity the lower nerve centers; those that 



36 



