POLAR EFFECTS OF MODERATE CURRENTS 219 



same ; hence the slight difference in the extent of trans- 

 mission in the two cases. As regards the sub-petiole R, the 

 anode-make, Am, showed no excitation. On break of the 

 circuit, again, no excitatory effects were observed at either 

 anode or kathode. This cycle of operations was repeated 

 once more, with precisely similar effects. 



The results of these experiments will be seen, in proper 

 sequence, in the following tabular statement, which sum- 

 marises the effects caused by currents acting in a given 

 direction — the direct — and its reverse, for the purpose of 

 corroboration. It should be remembered that at any 

 given moment, when a point on the one sub-petiole is made 

 kathode, K, a point on the other is simultaneously made 

 anode, A'. Excitatory contraction or closure is denoted 

 by C,v and the direction of the arrow indicates the trans- 

 mission in intra- and extra-polar directions. O denotes 

 absence of excitation. 



■ Table I. — Effect of Feeble Current on Leaflets of Mimosa 



The results given in the above table may be expressed in a 

 more condensed form as follows : — 



Table II. — Leaflets of Mimosa under Feeble Current 

 E.M.F. =4 volts; current = "j micro-ampere 



