[A]

Sept 4th

Tropaeolum minus 1877

Sept 3d

Marked during day 24 leaves most of which were inclined about 45° to light, but some were horizontal, viz the latter were leaves on depending trailing branches: everyone of them next at night were vertical. On morning of Sept 4th recovered their they resumed their original position, & at night were again vertical & on morning of 5th again inclined as before or horizontal. (The petioles of those which were inclined to the light during the day were inclined, but at right angles to the lamina: at night the uppermost part of petiole for alm 1/4 of inch in length was still at right angles to lamina; but beneath this a portion generally of from 1/2 to 1 inch in length is was curved, & it is this curvature which causes leaves lamina to become vertical, & this curvature disappears in the day. See diagram at back made by tracing peduncles & section of leaves, gathered at night.—)

Sept 5 at 8° 18' A.m Shutter opened at about 6°. 15' put pan with plants in quite dark cupboard: at observation for 5°) 11° 15' no depression of blades. — 3° 15 no depression: — 5° 20' I think a little declined, but some still sub-horizontal???— 8° 45' P.m. no difference in position not gone to sleep!! 10° 30' P.m. no difference.) (note inherited sleeping Habit)

Sept 6th 8° A.m leaves in same position & have never gone to sleep & now placed plant in window to N.E. into which the Sun never shines: at night 8° 30', all the leaves on front of plant, facing to light gone to sleep with petioles bent, but many to the back & the depending leaves on both sides not gone to sleep. To On the left side, (of the leaves encircled with thread) only those on tall shoot gone to sleep. All this agrees with what I observed in greenhouse. viz that plants on inner or dark side did not go to sleep.

no external difference perceptible in bending part of Petiole.

(over) (a)

(B

If the horizon to the N.E late in evening had been brighter, I shd have said that leaves became vertical to face last trace of light & remained fixed in this position till the light reappeared next morning. It is surprising what a little obscurity during the day prevents the leaves at night going to sleep, as shown by those on back of plants in greenhouse & in the present experiment.— After the plants had gone to sleep to above extent they were placed in dark cupboards & next morning (Sept 7' 9° A.m.)— were examined & all those which were asleep last night were now awake, so they have an inherited habit of waking, but not an inherited habit of sleeping.) Sept 7' 9° 5' A m. placed plant in Verandah on S. side of House until 12° but the sun was too hot & soil had got dry, so watered & put pan in study window again— leaves highly inclined, but far from vertical.

[Bv]

Tropæolum Canariense

Sept 6th 8° 20' P.m. a large number of leaves facing in all directions (marked with white thread) with laminæ vertical & petioles close to blade at rt ∟ to blade, but near just below bent at right angles.) (Sept 7 I found that these leaves are almost vertical during the day; so now 2° P.m I have marked several which though highly inclined are not vertical.

Sept. 7. 8° 30' P.m The leaves have become a little more vertical.

Sep 8' 7° 40 a.m (shutter open at 6° 15') plant awake & leaves certainly less vertical than they were last night.

Sept. 13' Put plants in greenhouse, & went at night but cd see no signs of plain sleep. —

(C

1877

Tropaeolum minus

Sept 7. 8° 20', P.m all the leaves towards light— well vertical.

It looks as if as soon as light failed they fell, but this does not agree with effect of dark cupboard:

(Sept 8th 7° 40' A.M. leaves well inclined, showing how quickly awake — shutters opened about 6° 15' before which extremely little light cd. enter.— Day cloudy — 12° put plants in dark cupboard.— 3° P.m. leaves not vertical, (perhaps a little more inclined that they were?) 10°. 15' P.m. The leaves in front of plant quite verti & asleep, those on the back, which had been less illuminated during the morning were not asleep. It appears that the sleep is here inherited with reference to a particular period of the 24°s but that— the leaves must have been stimulated exposed during the same for some hours to the light.)

Sept 9th. 10° 30' A.m. The leaves here certainly awakened (for standing behind the plants I cannot see the under side of the leaves). 10° P.m a few of the leaves (plants kept all the day in dark cupboards) have gone to sleep, but the far greater number not so.—)

(Sept 10th 9° 45' The few leaves which were asleep last night are now awake) in the dark The plants were placed than 9° 45' placed in study window towards which they were already naturally directed from having been thus kept, but they bent still more eagerly to the light

At night all went to sleep more conspicuously than I have ever before

(D

Tropaeolum minus

seen them; so that the blade of all were vertical, accepting a very few leaves on the back of plant & a few on some depending shoots

(Sept 11th. 6°. 45' They had now been illuminated by shutter having been open for 1/2 25' hour & were well awake, all the blades being directed (for plants stood on very low table some way beneath with leaves only just below sill of window) at about 45° to zenith. I then (6° 45') turned pot round so that the leaves were directed at 45° to interior of room (well lighted for days clear) with there backs or under surface to the N.E. window, but down toward the ground.

(by 11° 10' a good many leaves had turned over so as to face light & many others were horizontal.) 8° 30' P.m. very few of the leaves have gone to sleep— only a few of those turned to the light, which were just the ones which before whilst on the shady side did not go to sleep. Those on the back or now shady side of the plant are all horizontal, though before these were just the leaves which went to sleep best. Turned the plants round again to their old original direction, so that the now horizontal leaves will tomorrow be exposed to the light.)

Sept 12th 9° P.m. All the leaves which during the day have faced the light are well asleep.

(Sept 13' 8° 35 A.m. Put plants after being then shortly exposed to light in dark cup-bords, but too old to be trustworthy — A few leaves in middle vertical: 10° P.m. no signs of sleep.)