:-!62 



GENERAL PHYSIOLOGY 



while the stimuhis was passing over a piece of nerve 3 em. in 

 leneth. It is thus found that the rate of conduction of the 



Fig. 154. — Du Bois-Reymond's spriiig-myograph. 



stimuhis in a frog's nerve under normal conditions amounts to 

 approximately 26 m. in the second. 



Other forms of living substance conduct the reaction considerably 

 more slowl}' and some to a very short distance only, the effect 

 being gradually extinguished with the distance. In very slowly 

 conducting objects the rate of conduction can be followed with the 



Fk;. ir.rj, — AsceudiDg limb of the myogrtiphic curve taken with tlic spring-myoy:i-:tph. R, Moment 

 of stimulation : i, beginning of the contraction upon stimulation of the nerve at a remote 

 place (Fig. 153) ; ;:', beginning of the contraction upon stimulation immediately at the 

 iiiuscle. Below, the cvnwe of the tuning forlt. 



eye. Thus, in Difflugia the rate of conduction of the ex- 

 citation can be very easily recognised under the microscope in the 



