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PLANTS THAT WIGWAG 
I SN’T IT ODD that certain plants act in so human a 
manner that they give the impression that they actu¬ 
ally can think! 
There are numbers of the bean group that act in this 
way. The ordinary clover, for example, is a member of 
the bean group, which means that it is a legume. When 
nightfall comes, it raises its three leaves and folds them 
into a nightcap which it wears until the sun comes out 
in the morning. 
The locust tree is a member of this bean family. Does 
it not bear a bean much like that which is eaten at din¬ 
ner time? The seed pod of the clover is not recognized 
as a bean until it is carefully examined. The leaf arrange¬ 
ment of the clover — one leaf at the tip of the stem and 
two opposite each other farther down — is the same in 
principle as that of the locust, which has many leaflets 
opposite each other. 
The acacia tree folds its locust-like leaves up tight at 
night. This sensitive plant is much like the locust in its 
leaf arrangement. The remarkable thing about it is its 
response to touch, in which action it stands in a class by 
itself. The leaf stem and the leaflets themselves may be 
standing erect in a normal position. Upon the slightest 
touch they immediately shrink and droop as though 
wilted. 
Another most remarkable member of this same family 
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