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Vegetable Marrow Apogeotropism

March 16th Plant 2 ft high in Pot tied to stick growing straight up. — terminal shoot curved to one side & glass filament fixed to it. (See tracing) fell from weight at first from 8º 35 to 9.8— Pot being laid horizontally, kept dark— traced on Vertical glass. By 10º 20 had risen & continued to rise till 4º P.m, but by 5º had fallen & travelled to one side.

Here apo-geotropism acts first much more energetically than afterwards— The rise from 9º 8º or 9º 15 to 4º was not absolutely straight, yet shows only trace of circumnutation compared with great circumnutation which commenced after 4º. Moreover after 3º 10 plant placed closer to glass so Tracing less magnified.

We may conclude that apogeotropism checks circumnutation.

We learn that stem is a circumnutation for it made ellipse in between about 4º 30' - 7. 30' ie in about 3º.— Next morning (cold) circumnutated very little. Stem curved for di considerable distance from apex, & stood on morning of 17' above 42º above Horizon; The filament on the terminal shoot stood only 22º above horizon, for this was curved up by the lower shoots in an oblique direction. The check to circumnutation probably is due to whole lower half of cylindrical stem growing more rapidly than the upper half. —