Reseatolies ou the Discliarwe of the Electric OriJ-an. 



51 



during the first response, but becomes imperceptible if the second 

 stimulus occm^s at a sufficient interval after the first." He report- 

 ed the efïect of temperature u\K)n the phenomenon and also gave 

 the discussion al)out the locality of this peculiarity. More recently 

 Lucas '"'reported his researches on the locahty of the same phenom- 

 enon by his ingenious method, and concluded that it is an after 

 effect of the disturbance propagating through a nerve or a nniscle. 

 In this paper he plotted many curves which represent the relation 

 between the interval of the two stimuli and the same from the first 

 stimulus to the connnencement of the second response, and not 

 only did he accept the behaviour of the delay of the second response 

 au;reeing with that of Gotch, so that he modified his first statement, 

 but he found that the interval between the first stimulus and the 

 second response becomes greater in some cases, when the second 

 stimulus is l)rought very near to the refractory period. Quoting 

 his words: "In the more complex cases with which I have 

 dealt, namely the excitation of nerve and the recording of the 

 consequent electric response in the innerviated muscle, it appears 

 that a new phenomenon inust be recognised; the electric response 

 becomes still later when the second stimulus is brought very near 

 to the first. This suggests an important difference associated with 

 the passage of the propagated disturbance through successive tissues 

 having unlike time relations." Now we shall reproduce here two 

 figures of such kind given in his paper. 



o oos 

 E.rj}. 11. 



The Journal of Physiology, Vol. 41, p. 63, li)10. 



