. Botany of the living plant. Botany. 130 BOTANY OF THE LIVING PLANT the hinge is raised: if it is greater on the upper side the hinge is depressed. This appears to be the mechanism of the so-called " Sleep-Movements " of the Leguminosae, Wood-Sorrel, and various other plants. But the point which gives the Sensitive Plant its name is that it also executes movements of a like nature in response to mechanical shock. The disturbance of walking roughly through a patch of Mimosa pudica leaves a broad track of completely transformed â vegetation. But if the stimulus be applied gently, step
. Botany of the living plant. Botany. 130 BOTANY OF THE LIVING PLANT the hinge is raised: if it is greater on the upper side the hinge is depressed. This appears to be the mechanism of the so-called " Sleep-Movements " of the Leguminosae, Wood-Sorrel, and various other plants. But the point which gives the Sensitive Plant its name is that it also executes movements of a like nature in response to mechanical shock. The disturbance of walking roughly through a patch of Mimosa pudica leaves a broad track of completely transformed â vegetation. But if the stimulus be applied gently, steps in the change can be Fig. 90. Shoot of Mimosa pudica. I. with leaves in the normal day-positioD. II. iu the night-position assumed at duslc, or after stimulation. B = inflorescences. (After Strasburger.) A gentle touch at the sensitive lower surface of the hinge at the base of the petiole makes the whole leaf fall, and the stimulus may then be extended outwards to the pinnae and successive pinnules. Or if the distal pair of pinnules be pinched, or stimulated with the hot head of an extinguished match, the stimulus received distally will extend downwards. The pinnules will fold in successive pairs, and finally the leaf as a whole will fall. If the stimulus be strong it may extend along the stem to other leaves. There may thus be a convevaiice of the stimulus to a distance. The movement following on shock is in the first instance due to stimulus of the protoplasts of the turgid cells, resulting in their loss. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bower, F. O. (Frederick Orpen), 1855-1948. London, Macmillan and co. , limited
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1919
