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Heliotropism

An upright Cot. of Phalaris & Brassica exposed to Lat light, will bow down till almost horizontal & will thus conquer apogeotropism, when acting at most favourable angle.— On other hand if these Cots & Hypocotyl are at first placed horizontally before strong lateral light & thus exposed simultaneously. They are to Heliotropism & Apogeotropism, the latter is victorious at first, though ultimately almost conquered. Now I can understand this only the effects of light accumulating, as might have been

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expected from Nachwirkung, like [illeg] light [illeg] continuously acting though if we understand rightly this is decried by Wiesner.— But apogeotropism will be continually acting.— This look therefore rather as if Apogeotropism were acted sooner than Heliotropism & as soon as full force exerted conquered Apogeotropism.

Sep 22/79/