(A

Cissus discolor.

The tendrils when cork-screw have a kink in middle like Cucurbitaceæ)

June 30th 7°. 25 P.m. at 10° (ie 2°. 35') had moved 180°. — moved with hands of watch & I believe so continued all night.— (N.B stem twists round stick in reversed direction) I saw tendril rise much more perpendicular in one part of course

July 1'. At 7° 40' set mark fresh (semicircle in 2°. 10')

12. 25' completed circle (ie in 4°. 45')

(semicircle in 2. 25)

5°. 15' second circle complete (ie in 4° 50')

9° 50' 10° 0 third circle complete (ie 4. 45

[in margin:] (All with watch)

The two drawings at back were taken at exactly opposite points & are lateral views: they show that depending leading shoot does not alter position, & the tendril itself is not spirally twisted. The movement

[Av]

[annotated sketches]

July 15th Put crumpled bits of paper for each branch to seize & it was curious what complicated convolutions each made.─

(B

is like taking leading shoot of any plant & pulling it from centre, making it gyrate without twisting, when any one leaf will always point in same direction. I suspect the tendril but little inclined it sweeps circle of only 4.8 inches in diameter, & probably runs up straight stem. the 2 sub-branches of tendril is not twist

July 2d Tendril was at mark at 9°. 5' (if the two circles had been completed at same rate as in day) it could have been there 1° 30' earlier)

Performed first circle (with watch) in 4°. 30'

second circle in 5°.

third circle (I went to bed) in (Red)

The tendrils are certainly slightly sensitive.

July 3d. This morning the Tendril became stationary; so it has moved at least from midday of June 30, July 1, July 2d, till late at night

3 or 4

[Bv]

July 6' New tendril moved with watch & stopped in evening — not sensitive —

― 7th goes on turning — but not sensitive.

July 8th During these 2 days I have occasionally pinched tendrils with finger & thumb & no effect — it occurred to me that opposed excitement. Accordingly I rubbed both branches externally & they greatly diverged. [sketch]

When they had come together. I first touched the one & then the other internally & they converged each in about 10' [sketch]

July 9th: the two branches separately touched one exteriorly & the other interiorly, took shape at [sketch] C; movement perceptible in 5'.

Looking at 2 branches in a line touched them, separately, after interval laterally; one on one side, one on other side & they bent laterally, at right angles to plane joining the two branches. They straighten slowly taking an hour or more. It is clear both branches are

(C

(Cissus)

separately & independently sensitive all round & bend towards whatever point touched.

I then rubbed long peduncle separately on both sides towards base; & on both sides in uppermost part; no movement ensued; not sensitive.

I afterwards tested tips branches & was found f movement just sensible in 4'.—

The peduncle of tendril, after branches have caught contract by spirally winding & so pulls up branch, or itself winds round twig. — so sensitive in some way.—

July 10' Exposed sensitive tendril for 6' in open bottle to S. Æther was sensitive afterwards— perhaps tendril cannot absorb. —

Two days ago I put crumpled bit of paper

[Cv]

Spont contraction

(D

(Cissus)

into 2 branches of tendril, which are seized in most complicated convolutions, & saw peduncle at that end spirally wound up, but not at other end; & not so in much older tendril which had caught nothing —

July 18' Cissus now projects a great distance beyond stick, horizontally, & the terminal tendril moves from side to side but shoot remains nearly stationary.— whether small movement due to shoot or weight of Tendril I know not.

Twice I b rubbed tendril with pencil, with just force to move it a little; this force extremely little; for tendril was attached to long flexible shoot & itself very flexible.— 6 inches long of Black common Cotton hung on tendril caused decided movement — one inch did not.

E)

6 inches again plainly acted, put on very gently & cotton thread so very soft — it acted very slowly, but effectually causing great flexure—

Three inches & one inch of thread did not act, or only very obscurely.—

A third time the thread acted but only slightly & slowly for it took 40' to bend the tendril. —

This bit of thread, (weighing 90 inches) 6 inch long weighed 14/100 of a grain = 1/7' of a grain

7 28 / 5

(Cissus.)