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LIFE MOVEMENTS IN PLANTS
by wound, gives rise to greater and more persistent retardation
of growth.
SUMMARY.
Mechani'al stimulus induces incipient contraction or re- tardation of rate of growth, the effect being similar to that induccd by electric _sti1nulus.
Stimulus by Contact or friction induces a retardation which is, relatively speaking, moderate. On the cessation of stimulus tho normal 'ntc of growth is restOrcd within an hour.
[ntcnsc stimulation caused by the wound givos rise. to grontcr and morn pvrsistont I'vtm'dn'iimi of growth.