(1

July 31

Bauhinia grandiflorus Itajahy seedling

First true leaf of curious shape, like two leaflets united: at night the 2 halves close by the upper surface & be come into close contact; but this peculiar movement does not essentially differ from opposite leaflets of Mimosa coming into contact.

Upper & more especially lower surface considerably repellent of water. — When the pulvinus is rubbed the two 1/2 leaves approach each other a little, but my study very cold — It appears as if touching point between the 2 1/2 leaves excited movement most

Syringing the leaflets with water at 83° F. did not cause movement. Three leaves of which I touched points are now in about 30' (?) completely closed!!! No I have no doubt the effect of bringing from window to middle of Study Table; for I rubbed filaments of two of same leaves in afternoon & it produced no effect in 30' but when pot placed in washing corner, the 2 leaves were found completely closed in 1/2 Hour 28'.—

(2

Aug 1'

Bauhinia

[sketch] Seedlings now a little older & double leaf fully expanded, sub-horizontal — in younger seedlings above horizon, in older seedlings below horizon — Shaking seedlings makes the midrib descend vertically & then the 2 laminæ are vertical — When expanded a vertical plane passing including the mid-rib passes through stem of plant.; & when closed a vertical plane passing going between closed laminae & running through midrib & pass through vertical stem. — In commencing sleep the 2 laminæ meet & mid-rib hangs down vertically & soon is is inclined backwards so that if prolonged wd. strike axis of plant half-way up stem. 7° 15' P.m the mid-rib has now crossed petiole & point projects behind [sketch]

(The petioles rise at night: one was stood at ∠ of 45° above horizon at 11° a.m & at 10° 15 P.m stood 75°, so had risen 30°. Another stood 50° above horizon at 11° & at night 10° 15' P.m at 84°, so had risen 34°. The midrib of one which stood in day almost horizontally & which in evening depended vertically & so had moved through 90° at 10° 15' stood on opposite side only 27° beneath horizon, so had travelled 90° + 63° =

(over

[2v]

(Bauhinia)

= 153° since 11° in morning — This is the most remarkable part of movement. In moving backwards the close leaf passes close on one side of petiole, against which it presses; — so moves in same plane in which the 2 half halves close together.

N.B The rising of petioles makes whole plant on each branch more compact & pyramidal, like a Lombardy poplar compared with Common poplar.

Less — surface exposed to zenith — But petiole of M. albida pudica fall at night, so hardly cause. —