THE FEELINGS OF PLANTS 103 



Darwin showed that the cotyledons of Phalaris 

 became " curved towards a distant lamp which 

 emitted so little light that a pencil held vertically 

 close to the plants did not cast any shadow which 

 the eye could perceive on a white card." In 

 another experiment it was shown that if seedlings 

 kept in a dark place were laterally illuminated 

 by a taper for a minute or two at intervals of 

 three-quarters of an hour, the little stems leaned 

 over to the direction from which the intermittent 

 light had come. Normally the extreme sensitive- 

 ness of leaves to the action of light is well seen in 

 the case of climbing plants, particularly when the 

 specimens are growing up a wall. Even though 

 the effort may entail considerable distortion of 

 stalk, the leaves are invariably brought round so 

 that the face of them is held outwards. It is 

 easy to understand that it is to the advantage 

 of most plants to bring their foliage into such a 

 position that a maximum amount of light is 

 secured. 



Movement towards the light is not an invariable 

 feature in the organs above ground of all plants. 

 In the case of the Ivy there is a distinct tendency 

 for the shoots to bend away from the light. 

 More strange still is the behaviour of the 

 tendrils of the Vine and Virginian Creeper. These 



