The
square was refixed, and on the 29th, that is, ten days after the first
square had been attached, and two days after the attachment of the last
square, the radicle had grown to the great length of 3.2 inches, and now
the terminal growing part had become bent away from the square into a hook
(see Fig. 68).
Fig. 68. Quercus robur: radicle with square of card attached to one side of
apex, causing it to become hooked. Drawing one-half natural scale.
No. 2. Square attached on the 19th; on the 20th radicle slightly deflected
from it and from the perpendicular; on the 21st deflected at nearly right
angles; it remained during the next two days in this position, but on the
25th the upward curvature was lessened through the action of geotropism,
and still more so on the 26th.
No. 3. Square attached on the 19th; on the 21st a trace of curvature from
the square, which amounted on the 22nd to about 40o, and on the 23rd to 53o
from the perpendicular.
No. 4. Square attached on the 21st; on the 22nd trace of curvature from the
square; on the 23rd completely hooked with the point turned up to the
zenith.
Pages:
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307