PERSONALITY OF PLANTS 
serves that purpose. A revolving root tip makes 
a very efficient drill with which the hardy 
plant may bore a way through refractory soil. 
It is claimed that the great whirling sweeps 
made by tendrils of various climbers are merely 
amplifications of the circumnutation occurring 
in all plant terminals. 
Before leaving the subject of scientific move- 
ment in the plant world, it will be of in- 
terest to briefly consider some of the vegetable 
motions which are called forth by the stimulus 
of touch. Almost everyone is familiar with 
the Sensitive Plant and its double rows of tiny 
leaves. Touch any one of them and the whole 
group will instantly begin to contract and bend 
toward the stalk. We say begin, for so slow is 
the transmission of the impulse that one can 
readily see its progress, as one after another of 
the leaves respond. 
A motion which has forethought and design 
behind it occurs in the leaves of the famous and 
crafty Venus Fly-Trap. Two sections of leaves 
edged with teeth-like nerve-hairs form the two 
halves of an enticing-looking bowl and cover. 
The slightest contact with one of the delicate 
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