SENSITIVE PLANT 



give us the best information about the study of plants, and 

 which are not very attractive little books, quite agree with 

 the ordinary views of the subject. 



For one finds in them that plants differ from animals in 

 being " incapable of motion." This, of course, just means 

 that an animal, or rather most animals, can walk, swim, or 

 fly about, whilst plants have roots and do not move from one 

 spot to another. But it is not true to say that plants cannot 

 move, for most plants grow, which means that they move, 

 and in some few cases, we find that plants behave very much 

 in the same way as animals do when they are touched or 

 excited in any way. 



We shall have to speak about tendrils, roots, and insect- 

 catching plants later on. But it is perhaps the Sensitive 

 Plant which shows most distinctly that it can shrink back or 

 shrink together when it is bruised or roughly handled. 



It will be described in its place, but just to show that 

 this plant can move of its own accord, it is only necessary 

 to hold a lighted or burning match about an inch or so below 

 the end of a long leaf. If one does this then all the little 

 leaflets begin to fold up, and finally the main stalk droops ; 

 soon afterwards other leaves higher up the stalk begin to be 

 affected in the same way, and fall limply down one after the 

 other. It is supposed that this movement frightens a grazing 

 animal, who will imagine there is something uncanny about 

 the plant and leave it alone. There are many respects in 

 which this reaction of the Sensitive Plant resembles that 

 found in animals. It does not take place if the plant is 

 chloroformed or treated with ether; the leaves also get 

 " fatigued " if too often handled, and refuse to rise up again. 



There are, however, only a very few plants in which an 

 immediate, visible answer to a stimulus can be detected. But 



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