20
LIFE MOVEMENTS IN PLANTS
was found permanently abolished at the death of the plant.
Fig. 6. Effect of physiological depression on diurnal movement of the petiole of Arenga saccharifera. The uppermost curve exhibits variation of temperature, (a), normal diurnal curve, (b), modification after 3 days' and (c) after 7 days' withholding of water.
These experiments conclusively prove that the periodic movement of the leaf-stalk induced by variation of temperature is a physiological phenomenon, and from analogy we are justified in drawing the inference that the movement of the Faridpur tree is also physiological. The question, however, was finally settled by the unfortunate
