18 



Hooker: Physiological observations 



the amount of bending decreased, the gland was moved through 

 successively smaller angles and the zone of bending was restricted 

 to shorter and more basal portions of the tentacle. 



Table VII 



Table VII shows the growth of another tentacle during 

 three successive reactions. The respective elongations were 0.2 

 mm., 0.12 mm. and 0.2 mm. During the first reaction Segments 

 4 to 7 grew. The rate of growth was most intense in the lowest 

 segment and decreased toward the apex. The second reaction 

 was produced by growth in Segments 5 to 7. Segment 4 did not 

 elongate. Here again the most intense growth was at the base. 

 In the third reaction growth was confined to Segments 6 and 7, 

 and was considerably more intense in the latter. Segments 4 

 and 5 did not increase in length. The tentacle was again stimu- 

 lated but did not bend. 



Table VIII 



A third example of this sort is given in Table VIII. The 

 reaction time of the first inflexion was i minute, 40 seconds. 

 Segments 2 to 5 increased in length. The rate of growth was 



