Page:Life Movements in Plants.djvu/95
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DIURNAL VARIATION OF EXCITABILITY
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apparent over-shooting in the line of recovery.

Fig. 27. Record of diurnal variation of excitability; it exhibits marked nyctitropic movement.
EFFECT OF TEMPERATURE ON VARIATION OF EXCITABILITY.
So far I have merely described the observed diurnal variation of excitability. We may next inquire whether