. The power of movement in plants. Plants; Botany. Chap. IV. CIECUMNUTATION OF STEMS. 203 found to be in constant movement. It crossed five divisions of the micrometer, that is, ^-Jo^li of ^^ inch, in 6 m. 20 s. There cuuld hardly be a doubt that it Tvas the stem which chiefly moved, for the tip did not get quickly out of focus; and tliis would have occurred had the movement been confined to the leaf, which moves up or down in nearly the same vertical plane. (3.) Linum usitatissimum (Linese, Fam. 39^\âThe stems of this plant, shortly before the flowering period, are stated by Fritz Miiller ('
. The power of movement in plants. Plants; Botany. Chap. IV. CIECUMNUTATION OF STEMS. 203 found to be in constant movement. It crossed five divisions of the micrometer, that is, ^-Jo^li of ^^ inch, in 6 m. 20 s. There cuuld hardly be a doubt that it Tvas the stem which chiefly moved, for the tip did not get quickly out of focus; and tliis would have occurred had the movement been confined to the leaf, which moves up or down in nearly the same vertical plane. (3.) Linum usitatissimum (Linese, Fam. 39^\âThe stems of this plant, shortly before the flowering period, are stated by Fritz Miiller (' Jenaische Zeitschrift,' B. v. p. 137) to revolve, or eircumnutate. (4.) Pelaryonium zonale (GeraniaccEB, Fam. 47).âA young plant, 7s inches in height, was observed in the usual manner; but, in order to see the bead at the end of the glass filament Fig. 71. m' g''). y'^^OMji^ â » Pelargonium zonale: circumnutation of stem of young plant, feebly illu- miuated from above. Movement of bead magnified about 11 times ; traced on a horizontal glass from noon on March 9th to 8 oj the 1 Ith. and at the same time the mark beneath, it was necessary to cut off three leaves on one side. We do not know whether it was owing to this cause, or to the plant having previously become bent to one side through heliotropism, but from the morning of the 7th of March to on the 8th, the stem moved a considerable distance in a zigzag line in the same general direction. During the night of the 8th it moved to some distance at right angles to its former course, and next morning (9th) stood for a time almost still. At noon on the 9th a new tracing was begun (see Fig. 71), which was continued till 8 on the 11th. Between noon on the 9th and 5 on the 10th ( in the course of 29 h.), the stem described a circle. This plant therefore circumnutates, but at a very slow rate, and to a small extent. (5.) Tiopaeolum mujus (?) (dwarfed var. called Tom Thumb); (Gerajii
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