Page:Life Movements in Plants.djvu/260

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LIFE MOVEMENTS IN PLANTS


Datum. all)“. I subjected it to periodic stimulation, and obtained from it a series of contractile responses. After recoVery from stimulus it regained its normal length which remained constant for some time as seen in the horizontal base-line. But as a result of successive stimulations, the mature style resumed its growth with increasing acceleration. This is seen in the recovery overshooting its former hori- zontal limit (Fig. 85).

FM. 8.3. Record of responses of a mature style in which growth had come to a Ship, l'p-mrvc shows contraction under stimulus. Renewal of growth at sixth response, after which growth-elongation i~l shown by the trend of the hare-line dmvnwards.

From the investigations that haVe been described in this and in the previous Papers an insight is obtained into the complexity of response arising from various factors. it has been shown that the sign of response is modified by the intensity of stimulus, by its point of application, and by the tonic condition of the responding tissue. The funda- mental reactions have, been found to be essentially the same in pulvinated, in growing and non-growing organs. The