. The power of movement in plants . Plants; Botany. Chap. VII. SLEEP OF LEAVES. 355 Bommet, les inferieures vers la base du petiole commun;" but the leaflets on a young plant observed by us in the green- house merely sank vertically downwards at night. The leaflets are raised in Sphxivphysa salsola, Golutea arborea, and Astra- galus uliyinosus, but are depressed, according to Linnaeus, in Qlycyrrhiza. The leaflets of Rdbinia psevdo-acacia likewise sink vertically down at night, but the petioles rise a little, viz., in one case 3°, and in another 4°. The circumnutating move- ments of a ter
. The power of movement in plants . Plants; Botany. Chap. VII. SLEEP OF LEAVES. 355 Bommet, les inferieures vers la base du petiole commun;" but the leaflets on a young plant observed by us in the green- house merely sank vertically downwards at night. The leaflets are raised in Sphxivphysa salsola, Golutea arborea, and Astra- galus uliyinosus, but are depressed, according to Linnaeus, in Qlycyrrhiza. The leaflets of Rdbinia psevdo-acacia likewise sink vertically down at night, but the petioles rise a little, viz., in one case 3°, and in another 4°. The circumnutating move- ments of a terminal leaflet on a rather old leaf were traced during two days, and were simple. The leaflet fell slowly, in a slightly zigzag line, from 8 to 5 , and then more rapidly; by 7 on the following morning it had risen to its diurnal position. There was only one peculiarity in the move- ment, namely, that on both days there was a distinct though small oscillation up and down between and 10 , and this would probably have been more strongly pronounced if the leaf had been younger. Coronilla rosea (Tribe 6).—The leaves bear 9 or 10 pairs of opposite leaflets, which during the day stand horizontally, with Fig. Coronilla rosea; leaf asleep. their midribs at right angles to the petiole. At night they rise up, so that the opposite leaflets come nearly into contact, and those on the younger leaves into close contact. At the same time they bend back towards the base of the petiole, until their midribs form with it angles of from 40° to 50° in a vertical plane, as here figured (Pig. 146). The leaflets, however, some- times bend eo much back that their midribs become parallel to and lie on the petiole. They thus occupy a reversed position to what they do in several Leguminosse, for instance, in Mimosa. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these
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Keywords: ., bookcentury1800, bookdecade, booksubjectbotany, booksubjectplants
