Eesearohcs on the Discharge of the Electric Orsan. 



No. 77. 



The modal latent periods of 1 and 2 in No. 77 were found by the formula .''o= V'.ii.c.. 

 Since the stimulus was indirect, it must be allowed that the values of the modal latent period 

 thus found may be somewhat larger than the correct values. 



In the doseending stiuuilus, tlio discbarge occurs by the 

 closiiig-stimiüus and in tlie ascending by tlie opening-stimnkis. 

 The positive direction of tlie ordinate on the oscillograms shows 

 the descending stimnlus. 



In Xo. 77, the modal latent period of the third experiment 

 shows extraordinary prolongation. The discharge was caused by 

 an ascending stimulation current of tolerably long duration and the 

 preceding discharge was that due to the descending current. The 

 succeeding discharges were evoked by the stimulus of the same 

 direction and the result was that, the shorter tlie duration the 

 shorter the modal latent periods, tliougli it is longer than the 

 normal. The prolongation may be interpreted either as the 

 effect of some local cliange caused l»y the ascending stimulating 

 current of long duration, of wliich the longer the duration, 

 the greater is the ])rolongation ; or as the influence of tlie 

 preceding stimulus which is recovered Ijy repeating the opposite 

 current. The former is more probal)le if the observation is 

 limited to this film only, l)ut in tlie discharge evoked by the 

 stimulus of the same direction in Oscillogram No. 70, it cannot 

 be observed that the modal latent period is prolonged. The 

 number of the series of experiments of the above kind is 

 onlv two, and therefore we cannot give a definite conclusion. 



