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(1

Cotyledons of Cabbage Red Variety 1877

Oct 7th The Cotyledons are not equal & a bristle was fixed almost longitudinally to the smaller one & the 2 were [sketch] Light covered thus, & a mark of triangular paper fixed beyond or on under side & vertical glass on near side. The marked cot. See diagram (1) first rose greatly between 10° 35' & 11°. 40' so that no doubt cd be made on glass. At 10° 47' the mark was placed in another position & dots commenced. The bristle was viewed a little obliquely. Observation continued till 10° 37 P.m. In this time the cot. went up 4 times & down 4 times. There was also lateral movement. It is clear that movement continues after dark. At 10° many of the cotyledons were almost closed & quite deserved to be called asleep.

The movement was not at all influenced by light, which was almost uniform.)

(Next morning (Oct 8) at 6° 45' end of bristle high up as shown in diagram (1) & rose considerably to 8°. (N.B. The figure became so complicated at 4° that I slided the glass & then continued, so that the dot made at 4° is in 2 places.—)

Oct 8th. After 8° the plant bent so much over to light, that twice I had to change marks.— The mark was placed closer to Cots, so this tracing

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Cotyledons Red Cabbage 1877

much exaggerated, but the same leaf occupied the same position. Tracing given in Diagram (2.)

The first dot made at 9°25' last at 5° 30: in these 8 hours went thrice down on horizontal — thrice up or horizontal. At 7° came into field again, but no mark made. Movements when it was getting dark much more rapid & continued moving quickly till 10° P.m, but not recorded. It is certain that cotyledons approach each other (& stand sub-vertically at night & open during day.—

(I tried thrice & could not detect that pinching caused any movement, but rather difficult as cots ate in constant movement)

(Oct. 8th on same day another plant observed: The line joining 2 cot. placed transversely to light & bristle fixed to the longer cot. with the mark close behind so that tracing greatly exaggerated. In this position movements better shown than in last case. see diagram 3. At first plant bent so much towards light, that first dot was made at 10° 3' continued till 4°, when bristle went beyond range of glass. At 5° 30' came on glass again & so continued till 8° 45' & at 9° went beyond glass again. Between 10°. 3' & 9° (ie 11 hours) went at least 4 times obliquely up & thrice down