It therefore circumnutated rapidly. Some of the lines run at
right angles to one another.
Fig. 74. Rubus (hybrid): circumnutation of stem, traced on horizontal
glass, from 4 P.M. March 14th to 8.30 A.M. 16th. Tracing much magnified,
reduced to half of original size. Plant illuminated feebly from above.
(7.) Rubus idaeus (hybrid) (Rosaceae, Fam. 76).--As we happened to have a
young plant, 11 inches in height and growing vigorously, which had been
raised from a cross between the raspberry (Rubus idaeus) and a North
American Rubus, it was observed in the usual manner. During the morning of
March 14th the stem almost completed a circle, and then moved far to the
right. At 4 P.M. it reversed its course, and now a fresh tracing was begun,
which was continued during 40 ? h., and is given in Fig. 74. We here have
well-marked circumnutation.
(8.) Deutzia gracilis (Saxifrageae, Fam. 77).--A shoot on a bush about 18
inches in height was observed. The bead changed its course greatly eleven
times in the course of 10 h. 30 m. (Fig. 75), and there could be no doubt
about the circumnutation of the stem.
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