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Aug 28th 1878

Tomato Seedlings Light

Painted Useless

2 seedlings with Hypocotyl painted with thick Indian ink from middle (measured) upwards including short petioles of Cot. & extreme base of Cots. — 2 other seedlings with basal Half (& beneath the ground) painted & exposed at 8° 45' in blackened box before S.W. window Morning bright

5° 10' P.m. They have behaved as might have been expected— The lower .2 or .25 of natural Hypocotyl stem does not bend, but upper part bends so much as to be nearly Horizontal &Cots faced the light— Now the 2 painted in upper part had this part nearly straight, but just below curved, but whole seedlings not so much curved as the natural seedlings

The 2 with painted basal halves had this part nearly straight, whereas upper unpainted half much curved, so that seedlings, nearly, yet not quite, faced light like the natural seedlings.

Aug. 29th The seedlings had grown nearly straight during night— Pot was reversed & placed at 8°. 30' a.m before S.W window & examined at 5° P.m.— (The painted parts were not again painted) The 2 with basal halves painted nearlyupright— The 2 with upper half painted were as much curved to light as any of natural seedlings, & the painted part had become slightly curved—

One seedling had upper surface & another had power surface of cotyledons painted, & both of them were as thoroughly well turned to light as any of the natural seedlings.—

Sept 2d exposed as above & treated same way at 10°. 35, examined 5° 40'

3' painted upper half of Hypocotyl & between base of cotyledons— 2 of these nearly straight, one with basal unpainted part curved to light, but the basal part in normal seedling does not bend down very low.— Of the 3 with basal ↘

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part painted— This part seems certainly straight.

(Exposed to apogeotropism in dark 5° 45'. Sept 2d — examined. 11° 20' 3° of the 3d with painted upper half, 1 considerably bent up. 2d very slightly 3d hardly at all.

Of the 3 with painted lower half, 2 have the upper half still directed to light & so have not been in the least acted on by apogeotropism; the 3d looks vertically up & so perhaps has been very slightly acted — The unpainted ones greatly bent upwards.)