. The power of movement in plants . Plants; Botany. 358 MODIFIED CIEUUMNUTATION. Chap. VIl. Circumnutation. — The circumnutating movements of four young shoots were observed during 5 h. 15 m.; and in this time each completed an oval figure of small size. The main petiole also circumnutates rapidly, for in the course of 31 m. (temp, 91° P.) it changed its course by as much as a rectangle six times, describing a figure which apparently, represented two ellipses. Fig. 149. Desmodium gyrans: A, stem during the day; B, stem with asleep. Copied from a photograph ; figurfes reduced. The movem
. The power of movement in plants . Plants; Botany. 358 MODIFIED CIEUUMNUTATION. Chap. VIl. Circumnutation. — The circumnutating movements of four young shoots were observed during 5 h. 15 m.; and in this time each completed an oval figure of small size. The main petiole also circumnutates rapidly, for in the course of 31 m. (temp, 91° P.) it changed its course by as much as a rectangle six times, describing a figure which apparently, represented two ellipses. Fig. 149. Desmodium gyrans: A, stem during the day; B, stem with asleep. Copied from a photograph ; figurfes reduced. The movement of the terminal leaflet by means of its sub- petiole or pulvinus is quite as rapid, or even more so, than that of the main petiole, and has much greater amplitude. Pfeffer has seen " these leaflets move through an angle of 8° in the course of from 10 to 30 seconds. A fine, nearly full-grown leaf on a young plant, 8 inches in height, with the stem secured to a stick at the base of the leaf, •vas observed from June 22nd to 8 a,m. June 24th ' Die Period. Beweg.,' p. 35-. 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 Darwin, Charles, 1809-1882; Darwin, Francis, Sir, 1848-1925. New York : D. Appleton
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Keywords: ., bookcentury1800, booksubjectbotany, booksubjectplants, bookyear18
