. The power of movement in plants . Plants; Botany. IV. DICOTYLEDONS. 231 tei'minal shoot of a young plant, growing very vigorously, was selected for observation. The young leaves at first stand up vertically and close together, but they soon bend outwards and downwards, so as to become horizontal, and often at the same time a little to one side. A filament was fixed to the tip of a young leaf whilst still highly inclined, and the first dot was made on the vertical glass at June 13th, but it curved downwards so quickly that by on the following morning it stood only a
. The power of movement in plants . Plants; Botany. IV. DICOTYLEDONS. 231 tei'minal shoot of a young plant, growing very vigorously, was selected for observation. The young leaves at first stand up vertically and close together, but they soon bend outwards and downwards, so as to become horizontal, and often at the same time a little to one side. A filament was fixed to the tip of a young leaf whilst still highly inclined, and the first dot was made on the vertical glass at June 13th, but it curved downwards so quickly that by on the following morning it stood only a little above the horizon. In Fig. 96 Fig. 96 fWJS'^. ^JD°£^ 55 \e°4o'^ Dianthus caryophyllus: circumnutation of young leaf, traced from June 13th to 16th. Apex of leaf stood, at the close of our observations, 8f inches from the vertical glass, so tracing not greatly magnified. The leaf was 5^ inches long. Temp. 15J°-17J° C. the long, slightly zigzag line representing this rapid downward course, which was somewhat inclined to the left, is not given; but the figure shows the highly tortuous and zigzag course, together with some loops, pursued during the next 2^ days. As the leaf continued to move all the time to the left, it is evident that the zigzag Hue represents many circumnutations. (6.) Camellia Japonica (CamelMacese, Fam. 32).—^A youngish leaf, which together with its petiole was 2i inches in length and which arose from a side branch on a tall bush, had a filament attached to its apex. This leaf sloped downwards at an angle of 40° beneath the horizon. As it was thick and rigid, and its 11. 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
