FREAKS OF PLANT LIFE. 



or covering those parts from which the tentacles are 

 absent. 



When any small object is placed on the glands, it 

 causes a movement in the tentacles. The impulse 

 is transmitted from those which are touched to others 

 which surround them, and, one by one, the tentacles 

 bend over towards the centre of the leaf, in order to 

 enclose the irritating object. If the latter is a living 

 object it is more speedily and effectively clasped 

 than a dead one. The time required to cause all 

 the tentacles to close over an object depends upon 

 circumstances. The inflection is more rapid over 

 a thin-skinned insect than a tough-coated one, and 

 the period varies from one to four or five hours for 

 all the tentacles to be closed down upon the captive. 

 If the glands are only touched by a hair or thread, 

 and nothing is left upon them, the tentacles at the 

 margin will curve inwards. This movement may be 

 caused by touching a gland three or four times, and 

 in ten seconds from being touched the movement 

 has been seen to commence. 1 



1 Withering states that in 1780 Mr. Whateley inspected 

 some of these leaves (£>. rotundifotia) and observed small 

 insects imprisoned therein. On Mr. W. pressing with a pin 

 other leaves, yet in their expanded state, he observed a 

 remarkable sudden and elastic spring of the leaves so as to 

 become inverted upwards, and, as it were, encircling the pin 

 which evidently showed the method by which the fly came 

 into its embarrassed position. 



