THE NERVOUS SYSTEM. 



197 



FIG. 102. DIAGRAM SHOWING THE RELATION OF SOME OF THE CELLS AND 

 FIBERS OF THE SPINAL CORD. Lateral aspect of the cord. 



a, Anterior median fissure ; ac, cells of the anterior horn ; an, anterior 

 root of spinal nerve ; c, axone ; co, collateral fibers ; e, fibers con- 

 necting higher brain centers with cerebellum; fi, sensory fibers of 

 fillet to the brain ; g, gn, go, ganglion of posterior root ; gr,. gray 

 matter ; ir, fibers of the posterior sensory tract ; I, fibers to cere- 

 bellum; m, cell in the anterior horn or column of gray matter; 

 n, spinal nerves ; o, cells in the posterior horn or column of gray 

 matter ; nc, nucleus gracilis and nucleus cuneatus ; nr, nucleus ruber ; 

 r, a fiber of posterior root ; rb, ganglion cells of medulla ; s, tract 

 of fillet to the brain ; sp, fibers of superior peduncle of the cere- 

 bellum ; t', fiber of crossed pyramidal tract; ts, point of decussation; 

 v, division of fiber x into its cranial and caudal extensions ; w, a 

 collateral of the longitudinal fiber ir. 



