. The power of movement in plants . Plants; Botany. Chap. I. PRIMULA. 45 14 oT; of the Fig. filament was, as far as could be ascertained, about inch. Belianthus annwis (Compositse).—The upper part hypocotyl moved during the day-time in the course shown in the annexed figure (Fig. 32). As the line runs in various directions, cross- mg itself several times, the movement may be con- Bidered as one of circximnu- tation. The extreme actual distance travelled was at least "1 of an inch. The movements of the cotyle- dons of two seedlings were observed; one facing a north- east window, and t
. The power of movement in plants . Plants; Botany. Chap. I. PRIMULA. 45 14 oT; of the Fig. filament was, as far as could be ascertained, about inch. Belianthus annwis (Compositse).—The upper part hypocotyl moved during the day-time in the course shown in the annexed figure (Fig. 32). As the line runs in various directions, cross- mg itself several times, the movement may be con- Bidered as one of circximnu- tation. The extreme actual distance travelled was at least "1 of an inch. The movements of the cotyle- dons of two seedlings were observed; one facing a north- east window, and the other 80 feebly illuminated from above as to be almost in darkness. They continued to sink till about noon, when they began to rise; but between 5 and 7 or 8 they either sank a little, or moved laterally, and then again began to rise. At 7 on the following morning those on the plant before the north-east window had opened so little that they stood at an angle of 73° above the horizon, and were not observed any longer. Those on the seedling which had been kept in almost complete darkness, sank during the whole day, without rising about mid-day, but rose during the night. On the third and fourth days they continued sinking without any alternate ascending movement; and this, no doubt, was due to the absence of light. Frimula Sinensis (Primulaceoe).—A seedling was placed with the two cotyledons parallel to a north-east window on a day when the light was nearly uniform, and a filament was afSxed to one of them. Prom observations subsequently made on another seedling with the stem secured to a stick, the greater part of the movement shown in the annexed figure (Pig. 33), must have been that of the hypocotyl, though the cotyledons certainly move up and down to a certain extent both diumg the day and night. The movements of the same seedling were traced HeUanthus annum : circumnutation of hypocotyl, with filament fixed across its summit, traced on a horizontal glass i
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Keywords: ., bookcentury1800, booksubjectbotany, booksubjectplants, bookyear18
