642 



MANUAL OF PHYSIOLOGY. 



organization and distribution of voluntary motor impulses. In 

 animals whose hemispheres are less complexly developed, such as 

 the dog or rabbit, the " basal agent" seems capable of carrying on 



FIG. 244. 



Diagram of some of the paths taken by nerve impulses in the brain and 

 spinal cord. C. Gray substance of cerebral cortex. c / '. Gray substance 

 of cerebellum. Or. Cranial nerves, some afferent and some efferent. M. 

 Motor (efferent) spinal nerves. S. Sensory (afferent) spinal nerves. 



more elaborate work, independent of the guidance of the higher 

 motor centres in the gray matter of the brain. 



