. The power of movement in plants . Plants; Botany. Chap. I. PHALAEIS. f53 Fisr. 49 action of light; and if any enters even temporarily on one side, they merely bend to this side in slightly zigzag lines. Of the three tracings one alone (Pig. 49) is here given. Had the observations been more frequent dnring the 12 h. two oval figures would have been described with their longer axes at right angles to one another. The actual amount of movement of the apex from »do to side was about •3 of an inch. The figures described by the other two seedlings resembled to a certain exttnt the one hero given.
. The power of movement in plants . Plants; Botany. Chap. I. PHALAEIS. f53 Fisr. 49 action of light; and if any enters even temporarily on one side, they merely bend to this side in slightly zigzag lines. Of the three tracings one alone (Pig. 49) is here given. Had the observations been more frequent dnring the 12 h. two oval figures would have been described with their longer axes at right angles to one another. The actual amount of movement of the apex from »do to side was about •3 of an inch. The figures described by the other two seedlings resembled to a certain exttnt the one hero given. A seedling which bad just broken through the ground and projected. only Jgth of an inch above the Phal"ris Ci'nari'ensis: circumnu- tation of a cotyledon, with a mark placed below the apex, traced on a horizontal glass, from Nov. 26th to 27th. Movement of apex ;-d 7 times, here reduced to one-half scule. 50) shows that the apex course ten times in the Fig. 50. surface, was next observed in the same manner as before. It was necessary to clear away the earth all round the seedling to a little depth in order to place a mark beneath the apex. The figure (Fig. moved to one side, but changed its course of the ten hours of observa- tion ; so that there can be no doubt about its circumnutation. The cause of the general movement in one direction could hardly be attributed to the entrance of lateral Ught, as this was carefully guarded against; and,we suppose it was in some manner connected with the removal of the earth round the little seedling. Lastly, the soil in the same pot was searched with the aid of a lens, and the white knife-like apex of a spsdling was found on an exact level with that of the surrounding surface. The soU was removed all round the apex to the depth of a quarter of an inch, the seed itself remaining covered. The pot, protected from lateral light, was placed under the micro- 4. Please note that these images are extracted from
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Keywords: ., bookcentury1800, booksubjectbotany, booksubjectplants, bookyear18
