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Geotropism— Canary grass

Cutting off tips

 not preventing apogeotropism

Dec. 6' 11° 10 A.m put 2 pots on sides, so almost horizontal in dark closet, mostly with tallest plants pointing in all directions

Dec. 7' 8° a.m. — Four of the plants had thin tips cut off (see former experiments) the following lengths .14, .12, .1, .07 of an inch & these were curved as much as others from apo-geotropism. Indeed the one cut off .14, which was a young plant was more curved than any of the others. The curvature was chiefly in uppermost part, so that the plants in these 2 pots presented a very different appearance from those same plants which had been when exposed to a lateral light. The blade of first leaf, protruded from many of seedlings was very little curved. Hence apo-geotropism almost confined to upper part; but not a zone like Heliotropism

Albino seedling. ie not red, but white with greenish tinge this was as much acted on by apogeotropism as the others— Exposed laterally to light at 8°. 5' a.m.

(Dec. 15th cut off .2 of inch from 3 seedlings about 1 inch high some a .1 of inch or lower more or less, & laid at 10°, 45' horizontal, but day cold & plants had been kept very hot, by 4° 30' P.m had hardly moved except the quite young plants, but next morning 10° 30', the 3 cut-off one were curved upwards.— The other plants had drops of syrup placed on lower sides so as to cause osmosis, but this did not interfere with apogeotropism.— nor did some slips of blotting paper which I had previously placed on their lateral sides.— One by One young seedling was bent in in opposition to apogeotropism! (over)

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Geotropism Canary grass

Dec. 7th 11° 25' several young plants about 1 inch high, measured, but with some shorter were placed in dark cupboard & pots made by eye horizontal at 11° 10 a.m.

Dec. 8th the plants were upturned, so that most of them lay quite flat in contact with soil. The base for 1/10' of inch was hardly or not at all bent, & therefore was a rectangular bend just above the 1/10th, & it is all rubbish of difference between bending from light & darkness & apogeotropism— Quite young plant Quite young seedlings were bent.

(At 11° 15' (Dec 8th) plant placed upright in same cupboard at 4° P.m. tips all vertical, so that they were of this shape [sketch] Tip risen & then

at 10° 10' P.m they were thus [sketch] & next morning

(Dec. 9th) 8° 30' a.m. this shape this upper portion much the more sensitive to apo-geotropism. [sketch] straighten say

Dec. 14th I cut off .2 from tip of plant .52 high & same amount from another seedling 1 inch high(?), but cd not feel sure whether geotropism had acted.— Gum with lamp-black smeared for about .2 below apex no effect in preventing geotropism, & I think slips of blotting paper with syrup no effect.—