. The power of movement in plants . Plants; Botany. Chap. VII SLEEP OF LEAVES. 373. perpenlioularly down, the movement of its apex was traced until ; and during this whole time it swayed from side to side, completing more than one ellipse. Bauhinia (Tribe 15).— Fig- 158 The nyctitropic movements of four species were alike, and were highly peculiar. A plant raised from seed sent us from South Brazil by Fritz Muller, was more especially observed. The loaves are large and deeply notched at their ends. At night the two halves rise up and close completely together, like the opposite leafl
. The power of movement in plants . Plants; Botany. Chap. VII SLEEP OF LEAVES. 373. perpenlioularly down, the movement of its apex was traced until ; and during this whole time it swayed from side to side, completing more than one ellipse. Bauhinia (Tribe 15).— Fig- 158 The nyctitropic movements of four species were alike, and were highly peculiar. A plant raised from seed sent us from South Brazil by Fritz Muller, was more especially observed. The loaves are large and deeply notched at their ends. At night the two halves rise up and close completely together, like the opposite leaflets of many Legumi- nossB. With very young plants the petioles rise con- siderably at the same time; one, which was inclined at noon 45° above the hori- zon, at night stood at 75°; it thus rose 30°; another rose 34°. Whilst the two halves of the leaf are closing, the midrib at first sinks vertically downwards and afterwards bends back- wards, so as to pass close along one side of its own upwardly inclined petiole; the midrib being thus di- rected towards the stem or axis of the plant. The angle which the midrib formed with the horizon was mea- sured in one case at dif- ferent hours: at noon it stood horizontally; late in the even- ing it depended vertically; then rose to the opposite side, and at stood at only 27° beneath the horizon, being directed towards the stem. It had thus travelled through 153° )^ a m" «"< °~ <- T o . o g S i g p a g rt S .2 . J S i spin's ° I. 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, bookdecade, booksubjectbotany, booksubjectplants
