THE MOTOR TRACT. 

 Fig. 159. 



319 



The motor tract. 



12, eighth pair ; 13, hypoglossal ; 14, spinal nerves ; 15, spinal acces- 

 sory of right side, separated from par vagum and glosso-pharyngeal. 



Fig. 160 (on the following page), the sensory tract (from Sir C. Bell). 

 A, pons varolii ; B, B, sensory tract separated ; C, union of posterior 

 columns ; D, D, posterior roots of spinal nerves ; E, sensory roots of the 

 fifth pair. 



The ganglia at the base of the brain are regarded by Dr. Carpenter as 

 constituting the true sensorium. a doctrine which he has es- . 



i i t Thesensonum. 



tablished by many weighty arguments, and which is doubt- 

 less one of the most important thus far introduced by any physiologist. 



The idea here intended to be conveyed is, that the thalami, striata, 

 sensory ganglia, and nervous arrangements below, constitute an isolated 

 apparatus ; distinct from which, and superadded, are the cerebral hem- 

 ispheres. 



From observations on the animal series, the conclusion seems to be un- 



