448 STUDIES IN GENERAL PHYSIOLOGY 



elements each of which may be considered as in its own 

 state of electrotonus. As a support for the correctness of 

 this idea I quote the interesting observation of Roux, to 

 which this investigator has recently again called attention: 



Every cell in an egg which is divided into a smaller or larger 

 number of cells (morula or blastula) reacts individually, giving rise 

 to altered electrical fields (special polarization) as long as the egg 

 is vigorous. If, however, the vitality of the egg is reduced by 

 cooling or poisoning (not sufficiently to cause death), the com- 

 plexus of cells reacts as a whole, in other words, like an egg which 

 is not yet divided into cells. 1 



If these two opposite conditions can occur in one and 

 the same animal (under only different conditions), it is per- 

 haps not extravagant to assume that the central nervous 

 system of Amblystoma may behave like a homogeneous 

 whole when subjected to the constant current, while the cen- 

 tral nervous system of Crustaceans may behave as a series of 

 separately irritable elements in its galvaiiotropic reactions. 

 Whether the central nervous system of Amblystoma behaves 

 in its galvaiiotropic phenomena as in its secretory processes 

 is a question still to be investigated. 



It seems to me that our experiments on the polar excita- 

 tion of the glands of the skin of salamanders may lead to a 

 different explanation of the liquefaction of protoplasm ob- 

 served by Kuhne at the anodal side of Actinosphserium 

 from that which he has given. 2 Kuhne compares this process 

 with the tetanus of contractile elements. Might we not 

 rather in this case be dealing with processes similar in nature 

 to phenomena of "secretion? One can readily understand 

 how violent phenomena of secretion brought about through a 

 strong electrical current might lead to a disintegration of 

 the substance of a tender Protozoon, since the much tougher 

 epidermis of Amblystoma goes to pieces at the anodal side 



1 Pflttf/ers Arehiv, Vol. LXIII, p. 512. 



2 Untersuchungen iiber das Protoplasma (Leipzig, 1864). 



