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Oct. 9th - 11th

Cassia— " sea-side"

Apogeotropism.

Cassia Tosa

Some seedlings were laid horizontally & observed in dark. One which was 1 1/2 inch high. was not acted on by apogeotropism, but still distinctly circumnutated in its horizontal position.— a young one — became bowed vertically up in 12º. One which was 1 1/4 high had its movement traced during 9th of Oct on vertical glass & on following day on the horizontal

(See Tracing) From 8º 10' when first laid horizontally to 8º 45 fell probably owing to weight of cotyledons, which are large then rose very slowly, during rose during next 2º 10' till it rose to its original position. It then rose very slowly till 10º 35' P.m. (ie for 11º 45' for nearly 12º) & during whole of following night & until 11º 30' a.m on the 10th & then circumnutated slowly. We see the influence of nachwirkung in difference of rate during first 2º 10' & following 12º. & 24º. — The line only slightly zig-zag.— This line a remarkable contrast with irregular zig-zag course pursued, when the hypocotyl had been deflected only about 20º by Heliotropism & recovered itself very slowly through apogeotropism.—

See account given under Heliotropism.

Only the upper above 1/4 of inch parts of hypocotyl is bowed upwards by apogeotropism. —