. The power of movement in plants . Plants; Botany. Chap. IV. DICOTYLEDONS. 233 the day, it is doubtful whether some of these cases ought not to have been included in the present chapter. (7.) Pelargonium zonale (Geraniacese, Pam. 47). — A young leaf, li inch in breadth, -with its petiole 1 inch long, borne on a young plant, was observed in the usual manner during 61 h.; and its course is shown in the preceding figure (Fig. 98). During the first day and night the leaf moved downwards, but circumnutated between 10 and On the second day it sank and rose again, but between 10


. The power of movement in plants . Plants; Botany. Chap. IV. DICOTYLEDONS. 233 the day, it is doubtful whether some of these cases ought not to have been included in the present chapter. (7.) Pelargonium zonale (Geraniacese, Pam. 47). — A young leaf, li inch in breadth, -with its petiole 1 inch long, borne on a young plant, was observed in the usual manner during 61 h.; and its course is shown in the preceding figure (Fig. 98). During the first day and night the leaf moved downwards, but circumnutated between 10 and On the second day it sank and rose again, but between 10 and 6 it circumnutated on an extremely small scale. On the third day the circumnutation was more plainly marked. (8.) CissuK discolor (Ampclidese, Fam. 67).—A leaf, not nearly Fig. 99. full-grown, the third from the apex of a shoot on a cut-down plant, was observed during 31 h. 30 m. (see Fig. 99). The day was cold (15°-16° C), and if the plant had been observed in the hot-house, the circumnutation, though plain enough as it was, would probably have been far more con- spicuous. (9.) Vicia faba (Leguminosse, Fam. 75).—A young leaf, 3'1 inches in length, measured from base of petiole to end of leaflets, had a filament affixed to the midrib of one of the two ter- minal leaflets, and its movements were traced during 51i h. The filament fell all morning (July 2nd) till 3 , and then rose greatly till ; but the rise this day was so great, com- pared with that which subsequently occurred, that it was probably due in part to the plant being illuminated from above. The latter part of the course on July 2nd is alone given in the following figure (Fig. 100)! On the next day (July 3rd) the leaf again fell in the morning, then circumnu- tated in a conspicuous manner, and rose till late at night; but the movement was not traced after , as by that time the filament pointed towards the upper edge of the glass. During the latter part of the night or early mor


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Keywords: ., bookcentury1800, booksubjectbotany, booksubjectplants, bookyear18