1 68 RALPH S. LILLIE. 



Further light appears to be thrown upon the connection 

 between bioelectric currents and formative processes by the 

 above described phenomenon of rhythmical cilia-like vibratory 

 movements of precipitation filaments. This phenomenon is fre- 

 quent in newly formed filaments from iron and copper. The 

 rhythm is typically slow, varying from one to five per second, 

 and the movements are found only in the smaller filaments 

 during the earliest stages of their formation, usually ceasing 

 within a minute or two after their first appearance; at times, 

 however, they may last for five minutes or more, especially with 

 copper filaments. It appears probable that the phenomenon 

 depends upon a rhythmical intermittency in the outflow of the 

 solution contained within the tubular filament. As shown above, 

 the metallic area at the base of the filament is an anode, the 

 corresponding cathode being situated outside. The flow of 

 solution through the tube is continuous so long as the extremity 

 remains open, and is accompanied by an electric current. If, 

 however, the opening be temporarily sealed by the deposition of 

 precipitate, both the liquid flow and the electric current must 

 at once cease; such a cessation of the liquid flow probably has a 

 certain mechanical effect upon the position of the filament, while 

 the electrical variation causes a change of surface-tension; and 

 it seems likely that both effects combine to cause a movement, 

 which has the effect of reopening the extremity of the filament and 

 renewing the former condition. A rhythm is thus started which 

 may continue for some time with often remarkable regularity. 

 The determining condition of the phenomenon would then be 

 the alternate disruption and reformation of a part of the tubular 

 membrane, with corresponding opening and closing of the elec- 

 trical circuit through the tube; the mechanical effects would 

 result partly from the interruption of the liquid flow, but prob- 

 ably chiefly from the electrocapillary variation. Both the energy 

 and the material for the process are furnished by the electric 

 current through the tube. 



knowledge is in many respects exact. If the transmission of the local excitation- 

 state is due to the formation of local electrical circuits having the properties of 

 electrical circuits in general, the difficulty of accounting for the rapid propagation 

 of the excitation-wave along a highly irritable and rapidly responding element 

 like a nerve-fibre at once disappears. 



