The Bindweed. 



CHAPTEK YII. 



THE SLEEP OF PLANTS. 



WHE2T the shades of evening spread over gardens 

 and fields the plant sfold their timorous leaves, 

 as if feeling some premonition of the darkness and cold 

 that are approaching. We have seen how sensitive 

 plants close up their leaflets as soon_as the absence of 

 their beloved sun has made itself felt, or when they 

 are touched by a foreign substance. This habit, how- 

 ever, is not peculiar to these delicate plants only ; it 

 is a feature of a great many other plants, which in- 

 vert their leaves at night in a manner entirely dif- 

 ferent from their normal arrangement during the 

 day. Their appearance is so completely changed that 



