214 



Messrs. J. B. Farmer and A. D. Waller. 



Nitrous oxide for 5 minutes. 

 Hydrogen for 5 minutes. 



Carbon dioxide for 3 mi- 

 nutes. 



Carbon dioxide for 4 mi- 

 nutes. 



Carbon dioxide for 2 mi- 

 nutes. 



Experiment III. 

 Elodea. 



Diminution of movement. 

 Diminution. 



Arrested, followed by 

 more rapid movement. 



Ditto. 

 Ditto. 



Nerve. 



Diminution of responses. 

 Diminution. 



Diminution from 15 to 5, 

 followed by augmenta- 

 tion to 35. 



Diminution, followed by 

 augmentation. 



Ditto. 



Time. 

 1 



5 

 6 

 7 

 8 

 9 



10 

 II 

 12 

 18 



16 

 17 

 18 



