310 NEEVE-TISSUE. 



The hypothesis becomes, perhaps, admissible that all we call positive 

 concrete knowledge f. i., 1, 2, 3, etc., or a, &, c, etc., primarily gained by 

 sense impressions is localized in special ganglionic elements, while abstract 

 or general nervous activity rests in the diffused, nucleated portions of the 

 gray substance between the ganglionic elements. Such diffused activities 

 are : hope, fear, imagination, dreaming, etc. The increase of knowledge 

 throughout life would mean that there was a corresponding new formation of 

 ganglionic elements. Intelligence could depend chiefly upon the number 

 of these elements, and their number could be increased by education and by 

 learning. Memory could be based on the grouping of bioplasson particles, 

 which at certain times might be brought into motion, and again might return 

 to relative rest. 



Nervous action, perhaps, depends entirely upon a contraction of the bio- 

 plasson reticulum. Should such a contraction be induced on the periphery 

 of the body, it would be conveyed to the center, and recognized as pain ; if, 

 on the contrary, contraction start in the center and be conducted to the 

 periphery, it would result in muscular movement. From this point of view 

 the designation of sensitive and motor nerves becomes superfluous, for 

 experiments have already proved that the same nerve can at one time be a 

 sensitive, at another time a motor, conductor. We need only assume sensitive 

 and motor stations in the centers, in connection with each other. What the 

 motor .agent is which causes movement in the bioplasson reticulum of the 

 central organ, as well as throughout the whole organism, we do not know, 

 and consequently are at liberty to give it any name. As regards the spinal 

 cord, the nerve action seems to be sufficiently plain. (See Fig. 131.) 



Reflex action, coordinate sensation, motion, and conduction from and to 

 the brain take place in separate routes, which must be in connection with 

 the sensitive and motor ganglionic elements by means of offshoots. The 

 multipolar form of these bodies, perhaps, may be accounted for in this way. 



