PLATE IV. STRUCTURE OF A NERVOUS MECHANISM. 

 Fig. 1. 



Diagram to show the possible relation to one 

 another of various circuits traversing a single 

 caudate nerve cell, a may be a circuit connecting 

 a peripheral sensitive surface with the cell ; 6 may 

 be the path of a motor impulse : c and d other 

 circuits passing to other cells or other peripheral 

 parts. A current passing along the fibre a might 

 induce currents in the three other fibres 6, c, d, 

 which, traverse the same cell. 



Diagram to show possible relation of fibres from caudate nerve cells of the spinal 

 cord, and fibres from cells in ganglia, as, for example, the ganglia on the posterior 

 roots, a is supposed to be the periphery ; the cell above b one of those in the 

 ganglion. The three caudate cells resemble those in the gray matter of the cord, 

 medulla oblongata, and brain. 



