Page:Life Movements in Plants.djvu/21

 

CONTENTS

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PART I.

RESPONSE OF PLANT ORGANS.

I.—THE PROBLEM OF MOVEMENT IN PLANTS

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Complexity of the problem—Effects of the different forms of stimuli—Diverse responses under identical stimulus—Modification of response determined by intensity and point of application of stimulus, and tonic condition of organ—Response of pulvinated and growing organs—Necessity for shortening the period of experiment •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •

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II.—THE "PRAYING" PALM TREE

Description of phenomenon—The Recording apparatus—Record of diurnal movement of the tree—Universality of tree movement—Cause of periodic movement—Periodic movement of trees, and diurnal variation of moto-excitability in Mimosa pudica—Relative effects of light and temperature—Physiological character of the movement—Transpiration and diurnal movement—Diurnal movement in inverted position—Effect of variation of temperature on geotropic curvature—Reversal of natural rhythm by artificial variation of temperature •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •          •

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