136 



ELECTRICITY AND PROTOPLASM 



[Cii. VI 



body next to the kathode, but none at the anode end. The 

 result that one obtains depends, ho\vever, to a certain extent, 

 upon the strength of the current that one employs. But NAGEL 

 did not, apparently, measure his currents, so there is no cer- 

 tainty that his results can be at once duplicated. Taking the 

 results for various Invertebrates as they are given, however 

 they are instructive. 



TABLE XIII 



f All the species in this table (all of which, except Ciona, are 

 Mollusca) show in their response a more or less close approach 

 to the type of Pelomyxa (excitation, rest ; rest, excitation) ; and 

 we may believe that with appropriate stimulus they would re- 

 spond in precisely that way. 



In a second class of cases the response of the whole animal 

 belongs to the katex type; thus two species examined by 

 NAGEL showed the following responses : 



TABLE XIV 



* Inconstant in occurrence. 



