FOLIAGE LEAVES: THE LIGHT-RELATION 
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FIG. 4. Two sensitive plants, showing the motile leaves. The plant to the left has its 
leaves and numerous leaflets expanded ; the one to the right shows the leaflets 
folded together and the leaves drooping. After KERNER. 
the morning and evening (see Fig. 170). As a result, the 
apex of the leaf points in a general north or south direction. 
It is a significant fact that when the plant grows in shaded 
places the leaves do not assume any such position. It 
seems evident, therefore, that the position has something 
to do with avoiding the danger of too intense light. It 
