CHAPTER XIII 
THE INDIVIDUAL PLANT 
In the last chapter, when referring to the sense-life of 
plants, we intentionally left out of consideration a diffi- 
cult little question which ought to be mentioned. 
Our own bodies, and those of all animals with a con- 
centrated nervous system, are so controlled by our will 
that we always think of ourselves and animals as in- 
dividuals, We transfer this idea to the higher plants, 
who to us seem individuals also, but as a matter of 
fact in them there is, so far as we know, no concentrated 
nervous system, and neither brain nor will power, 
The various cells which make up a plant are neither 
entirely free nor are they without individuality of their 
Own. Some very interesting cases have been lately 
described in which one almost seems to see the plant 
rigorously sacrificing some of its members for the 
benefit of the survivors. 
The youngest leaves or shoots are those which are 
least specialised, and in which it seems the protoplasm 
is least exhausted. They have more adaptability, being 
able to suit themselves more readily to changes in climate 
or soil conditions, or to differences in the supply of 
moisture or sunlight. Old leaves, on the other hand, 
are not so well able to withstand sudden and unusual 
changes in temperature, long periods of drought or of 
darkness.1. This principle must not be carried too far, 
but perhaps explains the following curious observation. 
When plants are withering or drying up the water is 
often withdrawn from the older leaves and stems, and 
concentrated in the young growing parts. 
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