114 TALKS AFIELD. 



through ellipses or circles several inches in 

 diameter. The parts of the tendril revolve 

 in such a manner as to strike the stem of 

 the plant if there were not some counteract- 

 ing motion. They avoid striking the stem 

 by bending abruptly upwards just before 

 they reach it, and after they have passed it 

 they again fall into their inclined position. 

 In most tendril-climbers the young shoot is 

 bent to one side in such a manner as to 

 avoid the revolving tendril. The concave 

 side of the tip of the tendril is highly sen- 

 sitive to a touch, and when it strikes a stick 

 it coils about it in one or two minutes. If 

 the tendril is rubbed it will begin to coil 

 and cease its motion, but after a time it will 

 resume its former shape and begin again to 

 revolve. Almost any touch, ever so slight, 

 will induce the coiling, although raindrops, 

 coming with much force, have no effect upon 

 it. Although the sensitive tendril coils so 

 readily about any support which it touches, 

 still if two tendrils should strike together 

 they do not coil, but shake hands and pass 

 by. If a vine be thrown from its support 

 to the ground so that the tendrils hang 

 downwards, these organs cease for the time 

 to revolve, but soon raise themselves to a 



