SENSITIVE PLANTS 



vibration of the ground caused by its approach ; and 

 should it step in amongst them, the tempting and 

 juicy fohage shrinks before it, for one plant conve3's 

 the shock to its neighbours by the touch of its own 

 leaves as they droop. Thus what was a moment 

 before a mass of tempting green leaves becomes 

 almost instantly in appearance very scrubby fare 

 for the animal which anticipated much better 

 refreshment. 



Some readers may, perhaps, be inclined to doubt 

 if the movements of these plants would protect 

 them from the attacks of grazing animals, but it is 

 interesting to observe that the stems of the exam- 

 ple illustrated, and of many other species besides, 

 are protected with strong and sharp spines. This 

 feature alone shows that such plants have had to 

 protect themselves against browsing animals ; and 

 now when they have turned down their leaves out 

 of harm's way, they present to their enemy, for 

 its first nibble, nothing but prickly stems ; so that 

 should the intruder not be awed by their uncanny 

 movements, but proceed with its intention, its first 

 mouthful would scarcely be agreeable after its 

 richer anticipations. 



Then, too, let us suppose that a hungry cater- 

 pillar climbs the stem of a sensitive plant and 

 endeavours to feed upon its leaves. The cater- 

 pillar, of course, has to reach a leaf by its stalk, 

 and in doing so it either gets thrown suddenly to 

 the ground by the prompt drooping of the leaf, or, 

 should it succeed in adhering, finds the succulent 

 leaflets gathered in a tightly-closed bundle, most 



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