[26]

Oct 24th /73/ Oxalis acetosella— & sensitiva

Potted kept in cool greenhouse. This morning I observed yesterday during very heavy rain that plant out of doors had leaves depressed, but as I have proved that cold thus acts I did not know whether it was beating of water or cold that acted; so this morning I syringed strongly the above plants with water at 72°; & in a few minutes almost every leaf young & old had 3 leaflets depressed on an average about 45°, some more less & some more. The younger leaves after so violent a syringing had leaves dry or only spotted, whilst the old leaves were well wetted — The leaves did not rise again for 1/4 of hour.

Case like Dandelion for here cold & watering causes depression at about same angle, but nearly so great & perfect a movement as sleep— With O. sensitiva the only difference is that movement is quicker & the position taken as far as leaflets concerned the same as sleep.

I do not very clearly see advantage of the 45°— will drops strike less violently on surface, I suppose so & less often to [illeg] & less [illeg] all the time during [gale] rain.

[in margin:] N.B the old leaves of Cassia do not go to sleep.

/over

[26v]

Oct 25th I shook for 1m pot with the Acetosella, & the leaves became very slightly depressed; I then squirted with warmish water at some in one part & they immediately became depressed - far more effect than mere shaking, & yet I shook them as violently as could any gale of wind.

O. sensitiva shaking seemed to have very little effect & syringing more. — Young leaves are wetted in drops when syringed.— Blowing with bellows very little effect, but the plant was rather torpid, a few leaflets slightly moved.

I then syringed with water at 62° & this produced far more effect, & on the young leaves the leaflets shut pretty well. — Water certainly seems to produce more effect than shaking or blowing. — All the leaves young & old were well spotted with water after syringing

O. acetosella. (Oct 25' 12°) plant had stood in greenhouse, temp. 55°

I blew on it violently with bellows for 1 1/2m, on half the plants, a little & but a little effect was produced — I then syringed gently the same half of pot for short time with water at 62°, & this almost instantly caused far more depression of the leaflets. The leaves were hardly more agitated by the water than by the blowing.

[27]

Oxalis acetosella

Oct 26 /73/7° 30' Am

Plants in greenhouse at temp of 50° put 3 leaves in water of same temp. after 20' only trace of depression of leaflets— Put at same time other 3 leaves in water at 71°, after 20; only trace of depression. —

I brushed several times lightly with my open hand the leaves of all the plants, after 3' perhaps a trace of effect after 20' a slight depression of som most of them

I then syringed strongly the plants on one side of large pot with water at 62° & the leaflets almost instantly became on this side much more depressed: no doubt the finer jets of water beat the leaves laterally about far more than shaking or brushing: or blow My jet was like heavy rain with a gale of wind. (at 11° 30', i.e 4h. afterwards I looked at the leaves in the water those in the cold in Garden were well depressed — those on plant in pot all elevated. — This in the 71° water & glass had been put in case & no doubt water had risen to 80° had expanded— We see potency of cold. —