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of the young leaves were far from coming into contact (see in Hothouse).

The terminal pair & even penultimate pair of young leaflets turned not only downwards but at a considerable angle backwards towards the base of the compound leaf. The whole compound leaf at 8.20 p.m. stood at an angle of 36° with the perpendicular, & next morning at 9h 45m a.m in my study this same leaf stood at 52° 1/2 with the perpendicular; it had therefore risen 16° 1/2 in the act of going to sleep, (like oxalis sensitiva) the rising having been conspicuous to the eye.

[45v]

The older leaves were not syringed

The terminals & penultimate were much more inclined, (as in sleep) & were inclined at a considerably higher angle than 56° to horizon.

[3v]

The older leaves were not syringed

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The main petioles are arched (does arc change during sleep?) & I measured angles by a line from joint of main petiole with axis to the joints of terminal leaflets.— By the 12° on the 30' in Hothouse main petiole had sunk a little more more to (viz 5° 1/2° 6°) ie to 64°.

I felt so much impressed that bloom on lower surface was not for protection during sleep, that I today 30th at 12° syringed the 3 young upper leaflets for 2m (placing plant out of doors in moderate wind) with water at 64°, (nearly the temp of the house), & within 1m afterwards measured the inclination of several leaflets, which before had all been horizontal, (as explained in p. 1)

The surfaces now sloped at various angles between 45° & 56° to the horizon: The terminals & penultimate were much more inclined, (as in sleep) & were inclined at a considerably higher angle than 56° to horizon: the front edge of one leaflet as having moved downwards through 45°, & the edge of other

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having moved down through angle of 54 56.°

The main petiole which of one leaf which it before (viz at 12°) had stood with perpendicular at p angle of 58° 1/2, after the syringing stood at 64° (& so remained until 1° 25') & had therefore become depressed 5° 1/2 (too little to be certain about). In appearance the leaves had become considerably depressed: Had they become more bowed? The upper surface of the leaflets were much spotted with wet, but not all wetted (bloom?) the lower surface were dry from owing fr the bloom; & these lower surface were well syringed, as I syringed obliquely— They wd naturally get much wet in this oblique position.

(a) Odd projecting glands, alive only on young leaves, yellow & secreting much matter placed between sub-petioles on upper surface of main petioles

[5v]

(a) Can this fluid act as grease or as a synovial secretion— In all the older leaves, as far as I saw this gland dry & blackened, & the leaflets on older leaves only turned through 90°.

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The syringing was finished at 12° 13m at 12° 46' h the leaflets had begun to bend up so as to make blades h move nearly horizontal — at 1° 20' most of the leaflets were horizontal, but some still somewhat inclined.

Nov. 30' 8° 45' P.m. measured angle between of divergence of 2 opposite leaflets asleep— & it was 50° — (ie 4 less than last night in my study.)

I measured angle from the perpendicular of 2 terminal on 2 distinct leaves & found one (red wool)— at an angle of 36° & the other white wool at only 14° turned inwards or to base of leaf— In the day, I think the 2 terminal leaflets are directed much forwards.

[sketch] 36° Perpendicular.

[sketch] Red wool leaf 84° 144° 1/2

(see next Page)

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Dec 1 1873 12°. First for the younger leaf at base of last page (Red wool), the divergence of the midribs of the 2 terminal leaflets was now 84°, so that each diverged from the prolonged line of the midrib 42°, or 48° from a line at right angles to the midrib; & as last night the midrib was pointed backwards 36° from the perpendicular, it must have moved 84° backwards from its position during the day, neglecting the downward movement. The midribs of the next pair diverged at 144°, & these bend a little backwards at night. The midribs of the 3rd leaflet formed a straight line.

Turning now to the next older leaf (white wool) the divergence of the terminal leaflets was 74°, & on the same principle

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as before, it must have moved backwards 51°. The divergence of the midribs of the next pair was 138°. The midribs of the 3rd pair in a straight line.

It is clear that if the terminal & penultimate leaflets merely twisted on their axes & simply became depressed during sleep, their midribs wd occupy the same position the divergence of their midribs wd be the same as in the day; but we have seen how the case is.

Shook the plant for exactly 1 minute in hothouse, & leaflets were then somewhat twisted. (Judging from 2 leaves brought from Eliz-, cutting them off causes the leaflets to become vertical, & at night they went to sleep in ordinary position, but the next day standing in water never resumed horizontal position; nor did putting one in water at 95° cause it to expand. —

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Dec 1. 12.30 There are only small drops on top of the glands, & the sub-petioles not at all wet. I put a little scraped indigo & vermillion on the summits of 2 glands on difft leaves, (viz on leaf with red wool & on terminal glands with thread)

Dec. 2d has never flowed down on to sub-petioles., though fluid did along chanelled main petiole.—

My view quite an error— Leaf with thread, some pairs with no glands & short as well as others; so with leaves from Elizabeth which moved at night...)

(Dec. 2d. at 12° 1° brought plant from Greenhouse & shook it intentionally during journey for 2m.; leaflets were depressed at the end of journey.— Before starting I measured angle of main petiole of younger leaf (red thread) with the perpendicular & it was 73° & so was after the Journey.— A second leaf white wool & older (third leaf on axis on stem) had angle before journey of 62 1/2° & after journey of 71°, so it had fallen become depressed 8° 1/2; which is contrary movement to sleep movement of main petiole.

Nevertheless with both leaves the main petiole seemed, after rough measure, to be less bowed after journey than before, as if it had straightened itself — (See Back)

[9v]

Dec. 2d— 9° 15' P.m. I measured the angle of petiole with the perpendicular when plant was fast asleep. in younger leaf (Thread) it was now only 60°, so that it had risen 13°: in older leaf white wool, it was now 50°, so that it had risen 12° 1/2°. I do not see any use in this rising of whole leaf which is now certain during sleep. The turning backwards of the terminal & penultimate leaflet, makes the whole series much more compact, as the terminal pair turn under the others. I observe that the midribs of 2 leaves terminal leaflets of 2 leaves are directed towards base (as already ascertained), & the midribs of the next pair or two are turned a little forward during sleep, (new fact,) so that they all tend to converge; but there is some variability, especially from age in positions of midribs or leaflets during sleep.

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Dec. 2d. I painted at 12° 30' indigo line on upper surface of sub-petioles from middle of main petiole on the upper surface of leaflet, now that (at 5°) they are asleep, the blue line face the main petiole & lies close to it; so that it has twisted only 90°; & we must remember that the lower surface of leaf faces the sky only obliquely in a much depending position & not horizontal as it was when the upper surface faced to zenith.— The difference between the older & nearly nearly vertical leaves & those with lower surfaces exposed seems to lie— in the end of sub-petioles close to blad blade being more closely pressed at upper margin to the main petiole bowed inwards to the main petiole, but I suppose it must be further twisted. The sub-petiole of the 2 terminal leaflets are in close contact, when their leaves are inverted, but are not so in the older terminal leaflets which are not inverted.

(Dec. 5' Pinching & pricking with needle the sub-petiole & main petiole in all sorts of places causes no movements—: I tried 2 leaves— one both good, one— one very good.—)

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Dec. 5. young leaflet full-grown. Lower surface beautifully silvery & dry after immersion: upper surface much spotted with large spots after short shaking in water at 55°; but the distal end of midrib alone distinctly silvery!!—

S Ether makes no difference on upper surface, still spotted with cold water— lower so the non-adhesion of water must depend on state of surface— Lower surface wetted & loses loses its silvery appearance, but not readily, by water after ether & can be blown almost dry.—

83°-82° for 1m no change in either surface.

94°-93° for 1m lower surface thickly spotted with wet, & silver also left in spots,— upper surface same state

91°-89 1/2° for 2m other half of the same leaf, was left in the same state as last, so that the 2m immersion made up for the lower temperature.