LEAVES AND LIGHT 



stalk of every separate blossom bends so that its head turns 

 to the best lighted or sunniest side. Thus, if you have 

 Foxgloves planted against a wall, every flower will turn 

 away from it ; if you plant them in a circular bed, every 

 one turns to the outside, so that every flower can get the 

 sunlight. 



Every one who has kept plants in a window knows that 

 the stems turn towards the light. This has the eff*ect of 

 placing the leaves where they can get as much sunshine as 

 possible. The leaves themselves are also affected by sun- 

 light. They seem to stretch out in such a way that they 

 absorb as much of it as they can. 



That, of course, is what they ought to do, for they want 

 to obtain as much as possible of the sunlight to carry on the 

 work of forming sugar and starch inside the leaf. 



Not only each leaf by itself endeavours to place itself in 

 the best light-position, but all the leaves on the same spray 

 of, for instance. Elm, Lime, or Horsechestnut, arrange them- 

 selves so that they interfere with one another as little as 

 possible.^ Very little light is lost by escaping between the 

 leaves, and very few of the leaves are overshaded by their 

 neighbours on the same branch. 



Thus all co-operate in sunlight-catching. But, when a 

 number of different plants are competing together to catch 

 the light on one square yard of ground, their leaves try 

 to overreach and get beyond their neighbours. 



On such a square yard of ground, it is just the competi- 

 tion amongst the plants, that makes it certain that every 

 gleam of light is used by one or other of them. 



Every one of all those plants of itself alters the slope of 



1 Kerner, Natural History of Plants; also Scott EUiot, Nature 

 Studies — Plant Life. 



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