EFFECT OF ETHER 297 



gave rise to acceleration, which is characteristic of the first 

 stage. In Tropaeohmi the petiole absorbs the vapour 

 more readily, consequently the enhancement of geotropic 

 reaction at the first stage is followed by an arrest at the 

 second stage (fig. 172, b). 



-Fig. 173. Effect of chloroform on geotropic response of the 

 terminal leaflet of Desmodium. 



Note enhancement at the first and reversal at final stage. 



Experiment 161. Effect on piilvinus of terminal leaflet 

 of Desmodium. — The leaflet was executing a slow up- 

 movement. Application of chloroform induced preliminary 

 enhancement of geotropic reaction in the course of 40 seconds. 

 Continued action induced a reversal of the geotropic move- 

 ment (fig. 173). 



Effect of Ether on Geotropic Curvature 



Experiment 162. Petiole of Tropaeolum. — After the 

 attainment of uniform geotropic up-movement, a speci- 

 men of Tropaeolum was subjected to the action of ether 

 vapour ; this induced a great enhancement of the move- 

 ment in the course of 3 minutes, as seen in the erection 

 of the curve and in wider spacing of the successive dots 



(fig- 174). 



Having thus obtained a definite proof of the enhancement 



