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Oct 5. 1878.

Phalaris— Blackened glass Pipes.

On upper half Bright Sun-shine all day

2 Pots placed in blackened box, lateral light before S.W window

Pipes varnished with shell-lac & Lamp-black as before with summit closed with black paper & disc of black paper on sand

Pot I. 6 plants with blackened pipes or caps— half as long or deep as seedlings exposed at 8° 20' a.m.

Young seedlings all a little curved to Light —(1) with basal part hardly at all bowed to light. (2 & 3) & 4 inclined to light, but base not bowed (5 & 6) almost as much bowed as any to light!!

These were drawn by Frank

see drawing in Envelope

Pot 2, 6 seedlings with blackened caps, exposed at 8° 40'

Rather older seedlings— All 6 of them with basal part much straighter than the free ones — The caps owing to growth do not now to extend to base down half-way

I must speak of only some transmitted effect. In the very young ones sensitive part extends lower down— The drawing will give length

(1

Oct 6' 1878

Phalaris blackened & white glass Tubes

pipes, at over basal half of seedlings.— 2 pots— only ones thus treated— a little circle paper over top of pipes, & resting on sand, with little mound of sand thrown up in front— In blackened Box — with lateral light— before S.W window— cloudy day.—

Pot I

4° 45— one with black pipe bowed down to ground— a second slightly

4 Pipe Bl

two nearly straight— upper parts as much bowed as any, or very nearly so.

(1 black Pipe greatly bowed, 4 slightly bowed — 3 upright. = 8)

Pot 2. 3 of the black pipes 4 Pipes inclined— one upright— I do not think

that the uprightness can be safely attributed to blackness of tubes because some of the seedlings with of the white glass tube were nearly upright— owing to mechanical difficulty of tilting them — some, were tilted— other not so—

On the whole I am inclined to think what to the inclination of the seedlings with black tubes on base is due to transmitted effect—

N.B. First describe & illustrate curvature to light. — Then show if upper half protected from light, though lower exposed all time to light— does not bend— or only a very little— especially if young, for then, sensitive zone seem to extend lower down — If lower half protected — upper parts bends in usual manner & so apparently does lower due to transmitted effect, but hard to prove this, as tubes offer mechanical difficulty— Then give bending beneath sand. Importance as showing that light must first produce some effect which

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Glass Pipes Basal Halves

can be transmitted, & 2d that it can hardly be a direct ؟؟ chemico-physical effect on cells, for if so the lower parts when illuminated all day would bend.—

(2

Oct. 15/ 1878

Phalaris— Gold-Beaters skin on Basal Half

Blackened twice with thick Indian ink— Sand-banked up round— Base — exposed in blackened boxes before S.W window— Cloudy day — Seedlings very poor ones, raised, from I believe poor seed.—

3 Pots— exposed at 9°a. m. examined at.—

Pot I

(1) unpainted as well curved as any generality ✓

(2) unpainted as well curved as any do ✓

2/7 d Basal part straight or almost straight.

(3) unpainted 6. high basal part rather straight ✓

(4) unpainted Pot basal part very slightly inclined, like most of other tall ones ✓

(5) unpainted do do, do ✓

(6) unpainted basal part straight ✓

(7) unpainted as much curved as any— a short one about 1/4 of inch ✓

(8) Painted — basal part quite straight, upper part curved opposed

(9) Painted basal part slightly inclined, judged by plummet— tip slightly inclined ½ oppose

(10) Painted tallish — most of them above 3/4 of inch,— one nearly 1 inch basal part straight & vertical by plummet— tip inclined

opposed (It is certain that in all —these cases the basal part halves of the free seedlings of equal height with those with basal part protected from Light were considerably. inclined to the light.) X

X Therefore in these tall seedlings upper part was not able to excite basal part to bend.

(11) Painted tallish do do do opposed

(12) Painted tallish do. do. do. opposed

(over)

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(13) Painted like 10, 11, 12 opposed

(14) Painted only .6 high— basal part very slightly inclined to light 1/2 opposed

(3

Oct 16 1878

Phalaris. Young—seedlings —with blackened gold-beater

Indian Ink on Basal half.— sand dug up removed all round round bases

 & then put on— after painting.— In blackened Box S.W. window— Hazy day.

exposed from 9°, 9° 15', & 9° 30' at 8° 40' a.m examined at 4° 30' 8°

Two seedlings 1/4 inch high.— Three seedling in 2d Pot .4 high.

Pot I

(1) basal Half quite perpendicular tried by plummet — tip or upper half well curved to light opposed

1/2 opposed

(2) basal Half, just perceptibly inclined (but rather obliquely) to light, tip curved (marked with Pin.) (a) (over

These 2 great contrast with all other freer ones in Pot I. 1/2 opposed

(3) Pot II. a little inclined to light (marked with pins) B over 1/2 opposed

(4) — quite vertical opposed

(5) inclined from light— opposed (this some— accidental cause such as resistance shrinking of covering) certainly not in least inclined to light.

Striking contrast with all the other many seedlings in Pot. It is conclusive that only exceptionally can upper half left exposed to light cause basal half to bend if all light be excluded from it. So that basal half require double action, viz light on it & transmitted action from above— Whereas upper half bends to light without receiving any transmitted action from below.

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(a) & (b) During night all the free ones become nearly straight, but these 2 (a) & (b) retained same inclination as before & therefore I do not believe that the slight inclination due to light— 2 had become curved from light, I suspect doubtfully due to a little paint having got on one side above tube.