VELOCITY OF TRANSMITTED IMPULSE 153 



In a tissue in optimum condition the velocity of trans- 

 mission is the same under feeble and strong stimulation. 



Fatigue depresses the rate of conduction of excitation. 



Velocity of transmission of excitation is enhanced at a 

 higher temperature. 



Excitation is transmitted in both directions ; but the 

 velocity is not necessarily the same in the two cases. 

 In Biophytum the velocity in the centrifugal direction is 

 greater than in the centripetal. 



