The bead moved seven times from side to side, and thus
described 3 ? ellipses in 10 3/4 h.; each being completed on an average in
3 h. 4 m.
On the previous day another seedling had been observed under similar
conditions, excepting that the plant was so
[page 17]
placed that a line joining the two cotyledons pointed towards the window;
and the filament was attached to the smaller cotyledon on the side furthest
from the window. Moreover the plant was now for the first time placed in
this position. The cotyledons bowed themselves greatly towards the light
from 8 to 10.50 A.M., when the first dot was made (Fig. 7). During the
Fig. 7. Brassica oleracea: conjoint circumnutation of the hypocotyl and
cotyledons, from 10.50 A.M. to 8 A.M. on the following morning. Tracing
made on a vertical glass.
next 12 hours the bead swept obliquely up and down 8 times and described 4
figures representing ellipses; so that it travelled at nearly the same rate
as in the previous case. during the night it moved upwards, owing to the
sleep-movement of the cotyledons, and continued to move in the same
direction till 9 A.
Pages:
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45