After 22 h. 30 m. this part of the radicle had become straight.

(8.) Radicle 12 mm. long, card affixed almost laterally: after 9 h. deflected laterally in a plane at right angles to that of the bean between 40o and 50o from the vertical and from the card. In the plane of the bean itself the deflection amounted to 8o or 9o from the vertical and from the card, in opposition to Sachs' curvature. After 22 h. 30 m. the extreme tip had become slightly curved towards the card.

(9.) Card fixed laterally: after 11 h. 30 m. no effect, the radicle being still almost vertical.

(10.) Card fixed almost laterally: after 11 h. 30 m. deflected 90o from the vertical and from the card, in a plane intermediate between that of the bean itself and one at right [page 137] angles to it. Radicle consequently partially deflected from Sachs' curvature.

(11.) Tip of radicle protected with goldbeaters' skin, with a square of card of the usual dimensions affixed with shellac: after 11 h. greatly deflected in the plane of the bean, in the direction of Sachs' curvature, but to a much greater degree and in less time than ever occurs spontaneously.

(12.) Tip of radicle protected as in last case: after 11 h. no effect, but after 24 h. 40 m. radicle clearly deflected from the card. This slow action was probably due to a portion of the goldbeaters' skin having curled round and lightly touched the opposite side of the tip and thus irritated it.

(13.) A radicle of considerable length had a small square of card fixed with shellac to its apex laterally: after only 7 h. 15 m. a length of .4 of an inch from the apex, measured along the middle, was considerably curved from the side bearing the card.

(14.) Case like the last in all respects, except that a length of only .25 of an inch of the radicle was thus deflected.

(15.) A small square of card fixed with shellac to the apex of a young radicle; after 9 h. 15 m. deflected through 90o from the perpendicular and from the card. After 24 h. deflection much decreased, and after an additional day, reduced to 23o from the perpendicular.

(16.) Square of card fixed with shellac behind the apex of a radicle, which from its position having been changed during growth had become very crooked; but the terminal portion was straight, and this became deflected to about 45o from the perpendicular and from the card, in opposition to Sachs' curvature.

(17.) Square of card affixed with shellac: after 8 h. radicle curved at right angles from the perpendicular and from the card. After 15 additional hours curvature much decreased.

(18.) Square of card affixed with shellac: after 8 h. no effect; after 23 h. 3 m. from time of affixing, radicle much curved from the square. (19.) Square of card affixed with shellac: after 24 h. no effect, but the radicle had not grown well and seemed sickly.

(20.) Square of card affixed with shellac: after 24 h. no effect.

(21, 22.) Squares of card affixed with shellac: after 24 h. radicles of both curved at about 45o from the perpendicular and from the cards.

(23.) Square of card fixed with shellac to young radicle: after [page 138] 9 h. very slightly curved from the card; after 24 h. tip curved towards card. Refixed new square laterally, after 9 h. distinctly curved from the card, and after 24 h. curved at right angles from the perpendicular and from the card.

(24.) A rather large oblong piece of card fixed with shellac to apex: after 24 h. no effect, but the card was found not to be touching the apex. A small square was now refixed with shellac; after 16 h. slight deflection from the perpendicular and from the card. After an additional day the radicle became almost straight.

(25.) Square of card fixed laterally to apex of young radicle; after 9 h. deflection from the perpendicular considerable; after 24 h. deflection reduced. Refixed a fresh square with shellac: after 24 h. deflection about 40o from the perpendicular and from the card.

(26.) A very small square of card fixed with shellac to apex of young radicle: after 9 h.

Charles Darwin

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