ELECTROLYTES IN LIVING MATTER 



103 



has any effect whatever, the stimulation occurs at the cathode. As 

 far as Infusorians are concerned, it is generally stated that the stimu- 

 lation occurs at the anode; but this statement is nevertheless wrong, 

 as Dr. Bancroft has recently shown.* If a constant current goes 

 through a Paramecium, the effect is that the position of the ciha on 

 the side of the cathode is altered, while on the side of the anode the 

 cilia retain their normal position, provided the current is not too strong. 

 The abnormal position of the cilia on the side of the cathode consists 

 in their free end pointing toward the oral end of the Paramecium. 

 It can be shown that this is the position of the cilia which is produced 

 by any kind of stimulus, mechanical or chemical. Budgett and I have 



shown that if a Paramecium be put into — solution of NaCl (or any 



salt), the Infusorian moves backward. This is due to the fact that the 

 salt causes a change in the position of the cilia, the latter pointing with 

 their free end forward instead of backward. If a constant current 

 is sent through a Paramecium, this change in the position of the cilia 

 occurs at the cathode end, while at the anode end no such change 

 occurs. It is therefore obvious that if we speak of the stimulating effect 

 of a constant current upon an Infusorian, we should state that this 

 stimulation occurs at the cathode side of the Infusorian. The opposite 

 statement is due to an observation made by Kiihne; namely, that Acti- 

 nosphcBrium, a Rhizopod, when subjected for some time to a constant 

 current, begins to disintegrate on the anode side.f This effect he called 

 a stimulation, or even tetanus. Maxwell and I, however, pointed out 

 long ago that this is merely a play on words, inasmuch as these phe- 

 nomena of disintegration (cytolysis ?) observed by Kiihne are caused 

 by electrolysis and are not necessarily connected with the stimulating 

 effect of the current. This is corroborated by observations made by 

 Budgett and myself.J 



Not only muscular contractions but phenomena of secretion can 

 also be produced by a current. When a current is sent through a 

 trough filled with water which contains an Amblystoma, a secretion 

 of whitish mucus appears on the skin wherever the outside of the 

 latter is struck by the current curves emanating from the anode (Figs. 

 18 and 19). § Here we have also apparently an anode effect of the 

 current. This effect depends partly, at least, upon a stimulation of the 

 central nervous system, and we do not know whether the stimulation 

 is anodic or cathodic. It may be that the influence of the central 



* F. W. Bancroft, Pfliiger's Archiv, Vol, 107, p. 535, 1905. 



t Kuhne, Untersuckungen uber das Protoplasma und die Contractilitat, Leipzig, 1864. 



X Loeb und Budgett, Pfliiger's Archiv, Vol. 65, p. 518, 1879. 



§ Loeb, Pfliiger's Archiv, Vol. 65, p. 308, 1896. 



