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LIFE MOVEMENTS IN PLANTS
alkalis induce antagonistic reactions, abolition of excitability with alkali taking place in a contracted, and with acid in an expanded condition of the pnlvinus.
The responses exhibit fatigue when the period of rest is diminished. The passage of constant current is found to remove the fatigue.
Response is enhanced on exposure to light, and dim- inished in darkness. Light is shown to exert a direct stimulating action on the pulvinas, independent of photo- synthesis.
