174 TILLEES OF THE GKOUND CHAP. 



it were, make the plants rock to and fro instead of 

 keeping steady. What he always wants to do is 

 to stop them when they have moved just to the 

 point that suits him, and that is the difficulty. 

 When they have reached that point they either go 

 on, or else they seem to want to come back to the 

 point they started from. They seem to remember 

 the peculiarities of their ancestors, and to feel a 

 kind of homesickness to be back to the point they 

 started from. 



Perhaps this may seem a fanciful way of putting 

 the matter, but, however we put it, it is of the 

 greatest importance to us. Civilised man prospers 

 and multiplies because, by working through long 

 ages, he has succeeded in producing all sorts of 

 wonderful plants, which feed and clothe him. But 

 those plants, cultivated and improved by man for a 

 few thousand years only, go back as wild plants 

 into the inconceivably distant past. In their cells 

 and fibres they have memories of the time before 

 man was ; let civilised man slacken his grip never 

 so little, and they will slip back into their ancient 

 ways. They will become poisonous, or unwhole- 

 some ; their seeds will grow small, their fruits bitter, 

 their roots will become tough and fibrous again, 

 and so on. 



When we read that man started to cultivate 

 plants thousands of years ago, that he has been 



