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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 12°. 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 8° 10' when first laid horizontally to 8° 45 fell probably owing to weight of cotyledons, which are large then rose very slowly, during rose during next 2° 10' till it rose to its original position. It then rose very slowly till 10° 35' P.m. (ie for 11° 45' for nearly 12°) & during whole of following night & until 11° 30' a.m on the 10th & then circumnutated slowly. We see the influence of nachwirkung in difference of rate during first 2° 10' & following 12°. & 24°. — 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 20° 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. —