16 



Hooker: Physiological observations 



The reaction is represented in Table V and Fig. io. No move- 

 ment was observed for an hour after stimulation. The region of 

 elongation and curvature was shorter than in the second reaction. 



Table V 



The acceleration of growth on the convex side was less than in the 

 previous reaction, and the tentacle was not fully bent for 7 hours 

 and 30 minutes. It remained in this condition 2 hours and 30 

 minutes before unbending again. The tentacle was again straight 

 25 hours after stimulation. It measured 3.98 mm., an increase of 

 0.24 mm. After this experiment the tentacle stopped secreting, 

 and no further reaction could be obtained. 



Fig. 10. A graph representing the third reaction of the same tentacle shown 

 in Fig. 9; drawn according to data in Table V, and on the same scale as Fig. 4. 



