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Sept. 12' Red Cabbage, apogeotropism of Hypocotyl. 4 ellipses

The hypocotyl of seedlings partially etiolated, 2 1/2 inch high, was laid almost horizontally so that axis of Pot was inclined only 14° above horizon.

But the hypocotyl had been somewh considerably bowed by having been exposed to feeble lateral light, & pot was so placed that the bowed upper part projected downward 30° or 40° below Horizon — Movement traced on vertical glass— Plant kept in complete darkness, except when observed for a few seconds & then very feebly illuminated. Plant arranged at 8° 30' a.m but the marks [sketch] were at first beneath vertical glass; hypocotyl rose rapidly & at 9° 20' the first dot cd be made on the glass. See Tracing. From 9° 20' to 12° continued to rise rapidly, & line only very slightly zig-zag, just a trace of. The Hypocotyl, then began to circumnutate & continued so to do till 10° 40' P.m. During night rose a little & next morning was beginning to circumnutate at still high level It is very interesting to observe that the irregular circular figures continued to rise, so that here we have circumnutation only slightly modified by apogeotropism. It shd be remembered that at this higher level, movements much much exaggerated, as marks seen traced very obliquely on vertical glass.— I did not think it worth while to continue observation, on the 13th as the same kind of figure wd certainly have been prolonged formed. At 8°. 30' a.m on the 13' the upper part of Hypocotyl was still 32° from the vertical; the extreme basal part having not having curved curved or, very little. There were many other seedlings in some same pot, & these had been acted on very differently; the most nearly vertical being only 12° from the →

[32v]

Ascended almost with hardly any zig-zags for 3h.10m. — then began to circumnutate for next 11 h. — describing figure which probably require 4 ellipses, each of which rose a little above the previous one.— During the night. & following morning was still rising in zig-zag line

(a) perpendicular, & the least modified 51° from the perpendicular; so that the one observed had been acted on in at very nearly an intermediate degree, compared with all the other seedlings— No doubt with time allowed it this one wd have become vertical & a figure exactly like that given wd have been formed at a still higher level on the horizontal glass— for tracing had nearly reached top of the vertical glass.—