TRANSCRIPTIE 🔗
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Chapter one of the Movement and Habits of Climbing Plants.
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This is a LibriVox recording. All LibriVox recordings are in
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the public domain. For more information or to volunteer, please
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visit LibriVox dot org. The Movement and Habits of Climbing
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Plants by Charles Darwin, Chapter one, Twining Plants. Introductory remarks,
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description of the twining of the hop torsion of the stems,
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nature of the revolving movement and manner of ascent stems,
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not irritable rate of revolution in various plants, thickness of
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the support round which plants can twine, species which revolve
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in an anomalous manner. I was led to this subject
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by an interesting but short paper by Professor Asa Gray
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on the movements of the tendrils of some cucurbitaceous plants.
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My observations were more than half completed before I learnt
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that the surprising phenomenon of the spontaneous revolutions of the
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stems and tendrils of climbing plants had been long ago
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observed by Palm and by Hugo von Mohl, and had
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subsequently been the subject of two memoirs by Duttroch. Nevertheless,
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I believe that my observations, founded on the examination of
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above a hundred widely distinct living species, contain sufficient novelty
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to justify me in publishing them. Climbing plants may be
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divided into four classes. First, those which twine spirally round
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a support and are not aided by any other movement. Secondly,
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those endowed with irritable organs, which when they touch any
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object class bit such organs consisting of modified leaves, branches,
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or flower peduncles. But these two classes sometimes graduate to
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a certain extent into one another. Plants of the third
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class ascend merely by the aid of hooks, and those
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of the fourth by routlets. But as in neither case
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do the plants exhibit any special movements, they present little interest,
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and generally, when I speak of climbing plants, I refer
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to the two first great classes twining plants. This is
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the largest subdivision, and is apparently the primordial and simplest
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condition of the class. My observations will be best given
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by taking a few special cases. When the shoot of
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a hop Humulus lupulus rises from the ground, the two
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or three first formed joints or inter nodes are straight
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and remain stationary, but the next formed whilst very young,
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may be seen to bend to one side and to
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travel slowly round towards all points of the guad compass,
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moving like the hands of a watch with the sun.
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The movement very soon acquires its full ordinary velocity. From
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seven observations made during August on shoots proceeding from a
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plant which had been cut down, and on another plant
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during April, the average rate during hot weather and during
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the day is two hours eight minutes for each revolution,
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and none of the revolutions varied much from this rate.
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The revolving movement continues as long as the plant continues
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to grow, but each separate inter node, as it becomes old,
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ceases to move. To ascertain more precisely what amount of
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movement each internode underwent, I kept a potted plant during
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the night and day in a well warmed room to
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which I was confined by illness. A long shoot projected
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beyond the upper end of the supporting stick and was
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steadily revolving. I then took a longer stick and tied
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up the chute, so that only a very young internode
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one three fourths of an inch in length was left free.
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This was so nearly upright that its revolution could not
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be easily observed. But it certainly moved, and the side
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of the internode, which was at one time convex, became concave, which,
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as we shall hereafter see, is a sure sign of
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the revolving movement. I will assume that it made at
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least one revolution during the first twenty four hours. Early
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the next morning, its position was marked, and it made
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a second revolution in nine hours. During the latter part
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of this revolution it moved much quicker, and the third
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Load full transcript
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circle was performed in the evening in a little over
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three hours. As on the six gating morning, I found
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that the shoot revolved in two hours forty five minutes.
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It must have made during the night four revolutions, each
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at the average rate of a little over three hours.
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I should add that the temperature of a room varied
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only a little. The choote had now grown three and
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one half inches in length and carried at its extremity
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a young internode one inch in length, which showed slight
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changes in its curvature. The next or ninth revolution was
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effected in two hours thirty minutes. From this time forward,
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the revolutions were easily observed. The thirty sixth revolution was
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performed at the usual rate, so was the last or
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thirty seventh, but it was not completed, for the internode
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suddenly became upright, and, after moving to the center, remained motionless.
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I tied a weight to its upper end so as
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to bow it slightly and thus detect any movement, but
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there was none. Some time before the last revolution was
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half performed, the lower part of the internode ceased to move.
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A few more remarks will complete all that need to
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be said about this internode. It moved during five days,
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but the more rapid movements after the performance of the
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third Revolution lasted during three days and twenty hours. The
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regular revolutions from the ninth to thirty sixth inclusive were
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effected at the average rate of two hours thirty one minutes,
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but the weather was cold, and this affected the temperature
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of the room, especially during the night, and consequently retarded
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the rate of movement a little. There was only one
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irregular movement which consisted in the stem, rapidly, making after
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an unusually slow revolution, only the segment of a circle.
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After the seventeenth revolution, the internode had grown from one
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to three fourths to six inches in length and carried
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an internode one and seven eighth inch long which was
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just perceptibly moving, and this carried a very minute ultimate internode.
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After the twenty first roun, the penultimate internode was two
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and one half inches long and probably revolved in a
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period of about three hours. At the twenty seventh revolution,
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the lower and still moving internode was eight and three
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eighths inch, the penultimate three and one half inch, and
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the ultimate two and one half inches in length, and
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the inclination of the whole shoot was such that a
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circle of nineteen inches in diameter was swept by it.
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When the movement ceased, the lower internode was nine inches
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and the penultimate six inches in length, so that from
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the twenty seventh to thirty seventh revolutions inclusive, three internodes
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were at the same time revolving. The lower internode, when
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it ceased revolving, became upright and rigid, but as the
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whole shoot was left to grow unsupported, it became after
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a time bent into a nearly horizontal position. The uppermost
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and growing internet roads still revolving at the extremity, but
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of course no longer round the old central point of
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the supporting stick from the changed position of the center
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of gravity of the extremity as it revolved. A slight
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and slow swaying movement was given to the long, horizontally
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projecting shoot, and this movement I at first thought was
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a spontaneous one. As the shute grew, it hung down
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more and more whilst the growing and revolving extremity turned
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itself up more and more. With the hop we have
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seen that three internodes were at the same time revolving,
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and this was the case with most of the plants
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observed by me. With all if in full health, two
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internodes revolved, so that by the time the lower one
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ceased to revolve, the one above was in full action,
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with a terminal internode just commencing to move. With Hoya Carnosa,
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on the other hand, a dependent shoot without any developed leaves,
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thirty two
inches in length and consisting of seven internodes
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a minute terminal one an engine length being counted continually
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but slowly swayed from side to side in a semi
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circular course, with the extreme internodes making complete revolutions. This
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swaying movement was certainly due to the movement of the
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lower internodes, which however, had not force sufficient to swing
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the whole shoot round the central supporting stick. The case
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of another esclepidaceous plant viz. Seropagia gardinierai is worth briefly giving.
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I allowed the top to grow out almost horizontally, to
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the length of thirty to one inches. This now consisted
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of three long internodes terminated by two short ones. The
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whole revolved in a course opposed to the sun, the
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reverse that of the hop at ra, between five hours
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fifteen minutes and six hours forty five minutes for each revolution.
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The extreme tip thus made a circle of about five
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feet or sixty two inches in diameter and sixteen feet
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in circumference, traveling at the rate of thirty two or
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thirty three inches per hour. The weather being hot, the
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plant was allowed to stand on my study table, and
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it was an interesting spectacle to watch the long shoot
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sweeping this grand circle night and day, in search of
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some object round which to twine. If we take hold
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of a growing sapling, we can, of course bend it
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to all sides in succession, so as to make the
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tip describe a circle like that performed by the summit
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of a spontaneously revolving plant. By this movement, the sapling
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is not in the least twisted round its own axis.
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I mention this because if a black point be painted
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on the bark on the side which is uppermost, when
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the sapling is bent towards the holder's body as the
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circle is described, the black point gradually turns round and
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sinks to the lower side, and comes up again when
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the circle is completed. And this gives the false appearance
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of twisting, which, in the case of spontaneously revolving plants,
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deceived me for a time. The appearance is the more
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deceitful because the axes of nearly all twiny plants are
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rarely twisted, and they are twisted in the same direction
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with the spontaneous revolving movement. To give an instance, the
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inter node of the hop of which the history has
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been recorded, was at first, as could be seen by
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the ridges on its surface, not in the least twisted.
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But when after these thirty seventh revolution it had grown
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nine inches long and its revolving movement had ceased, it
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had become twisted three times round its own axis in
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the line of the course of the sun. On the
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other hand, the common convolvulus, which revolves in an opposite
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course to the hop, becomes twisted in an opposite direction. Hence,
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it is not surprising that Hugo von Muel page one, O, five,
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one O eight, et cetera, thought that the twisting of
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the axis caused the revolving movement. But it is not
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possible that the twisting of the axis of the hop
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three times should have caused thirty seven revolutions. Moreover, the
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revolving movement commenced in the young internode before any twisting
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of its axis could be detected. The internodes of a
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young Siphomeris and Lecntia revolved during several days, but became
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twisted only once round their own axes. The best evidence, however,
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that the twisting does not cause the revolving movement is
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afforded by many leaf climbing and tendril bearing plants, such
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as Pissum sativum, en Chinocytis lobata, Bignonia capriolata, a Chremocarpus
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scaber and with the leaf climbers Solanum, jasminoids, and various
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species of Clematis, of which the internodes are not twisted,
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but which, as we shall hereafter see regularly perform revolving
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movements like those of true twining plants. Moreover, according to
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Palm page thirty ninety five and Rule page one forty
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nine and Leon, internodes may occasionally, and even not very rarely,
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--> 00:13:40.639
be found which are twisted in an opposite direction to
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the other internodes on the same plant and to the
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course of their revolutions. And this, according to Leon page
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three fifty six, is the case with all the internodes
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of a certain variety of Phasiolus multiflorus. Internodes which have
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become twisted round their own axis, if they have not
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ceased to revolve, are still capable of twining round support,
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as I have several times observed. Mal has remarked page
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one eleventh that when a stemmer twines round a smooth
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cylindrical stick, it does not become twisted. Accordingly, I allowed
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kidney beans to run up stretched string and of smooth
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rods of iron and glass one third of an inch
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in diameter, and they became twisted only in that degree,
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which follows as a mechanical necessity from the spiral winding.
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The stems, on the other hand, which had ascended ordinary
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rough sticks, were all more or less and generally much twisted.
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The influence of the roughness of the support in causing
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axial twisting was well seen in the stems which had
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twined up the glass rods. For these rods were fixed
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into split sticks below and were secured above to cross sticks,
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and the stems in passing the these places became much twisted.
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As soon as the stems which had ascended the iron
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rods reached the summit and became free, they also became twisted,
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and this apparently occurred more quickly during windy than during
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calm weather. Several other facts could be given showing that
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the axial twisting stands in some relation to inequalities in
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the support, and likewise to the shoot revolving freely without
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any support. Many plants which are not twiners become in
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some degree twisted round their own axis. But this occurs
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so much more generally and strongly with twining plants than
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with other plants, that there must be some connection between
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the capacity for twining and axial twisting. The stem probably
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gains
rigidity by being twisted on the same principle that
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a much twisted rope is stiffer than a slightly twisted one,
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and is thus indirectly benefited so as to be enabled
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to pass over in a quality in its spiral ascent,
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and to carry its own weight when allowed to revolve freely.
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I have alluded to the twisting which necessarily follows on
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mechanical principles from the spiral ascent of a stem, namely
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one twist for each spire completed. This was well shown
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by painting straight lines on living stems and then allowing
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them to twine. But as I shall have to recur
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00:16:26.080 --> 00:16:29.799
to this subject under tendrils, it may be here passed over.
239
00:16:30.919 --> 00:16:34.080
The revolving movement of a twining plant has been compared
240
00:16:34.159 --> 00:16:36.840
with that of the tip of a sapling moved round
241
00:16:36.919 --> 00:16:39.960
and round by the hand held some way down the stem.
242
00:16:40.399 --> 00:16:44.200
But there is one important difference. The upper part of
243
00:16:44.240 --> 00:16:48.960
the sapling, when thus moved, remains straight, But with twining plants,
244
00:16:49.000 --> 00:16:51.960
every part of the revolving shoot has its own separate
245
00:16:52.039 --> 00:16:56.840
and independent movement. This is easily proved for when the
246
00:16:56.960 --> 00:16:59.960
lower half or two thirds of a long revolving shoe
247
00:17:00.240 --> 00:17:03.720
is tied to a stick, the upper free part continues
248
00:17:03.840 --> 00:17:07.880
steadily revolving, even if the whole shute except an inch
249
00:17:08.039 --> 00:17:11.559
or two of the extremity be tied up. This part,
250
00:17:11.799 --> 00:17:15.720
as I have seen in the case of the hop ceropagia,
251
00:17:16.039 --> 00:17:21.039
convolvulus et cetera, goes on revolving, but much more slowly.
252
00:17:21.440 --> 00:17:24.480
For the internodes, until they have grown to some little length,
253
00:17:24.880 --> 00:17:29.279
always move slowly. If we look to the one, two,
254
00:17:29.400 --> 00:17:32.720
or several internodes of a revolving chute, they will be
255
00:17:32.880 --> 00:17:35.839
all seen to be more or less a bowed, either
256
00:17:35.960 --> 00:17:40.440
during the whole or during a large part of each revolution. Now,
257
00:17:40.480 --> 00:17:43.319
if a colored streak be painted this was done with
258
00:17:43.440 --> 00:17:46.839
a large number of twining plants along we will say
259
00:17:47.119 --> 00:17:51.279
the convex surface, the streak will, after a time, depending
260
00:17:51.319 --> 00:17:54.359
on the rate of revolution, be found to be running
261
00:17:54.480 --> 00:17:58.039
laterally along one side of the bow, then along
the
262
00:17:58.119 --> 00:18:02.680
concave side, then latter on the opposite side, and lastly
263
00:18:02.759 --> 00:18:08.160
again on the originally convex surface. This clearly proves that
264
00:18:08.240 --> 00:18:12.880
during the revolving movement the internodes become bowed in every direction.
265
00:18:13.839 --> 00:18:17.640
The movement is in fact a continuous self bowing of
266
00:18:17.720 --> 00:18:22.160
the whole shoot, successively directed to all points of the compass,
267
00:18:22.480 --> 00:18:27.480
and has been well designated by Sacks as a revolving nutuation.
268
00:18:28.799 --> 00:18:32.279
As this movement is rather difficult to understand, it will
269
00:18:32.319 --> 00:18:36.039
be well to give an illustration. Take a sapling and
270
00:18:36.119 --> 00:18:38.559
bend it to the south, and paint a black line
271
00:18:38.599 --> 00:18:42.960
on the convex surface. Let the sapler spring up and
272
00:18:43.039 --> 00:18:45.799
bend it to the east, and the black line will
273
00:18:45.839 --> 00:18:49.119
be seen to run along the lateral face fronting the north.
274
00:18:49.839 --> 00:18:52.119
Bend it to the north, the black line will be
275
00:18:52.160 --> 00:18:55.680
on the concave surface. Bend it to the west, the
276
00:18:55.720 --> 00:18:59.240
line will again be on the lateral face, and when
277
00:18:59.319 --> 00:19:02.000
again and to the south, the line will be on
278
00:19:02.079 --> 00:19:07.000
the original convex surface. Now, instead of bending the sapling,
279
00:19:07.359 --> 00:19:10.519
let us suppose that the cells along its northern surface
280
00:19:10.799 --> 00:19:13.079
from the base to the tip were to grow much
281
00:19:13.119 --> 00:19:17.000
more rapidly than on the other three sides. The whole
282
00:19:17.079 --> 00:19:20.759
chute would then necessarily be bowed to the south and
283
00:19:20.880 --> 00:19:25.160
let the longitudinal growing surface creep round the chute, deserting
284
00:19:25.440 --> 00:19:28.519
by slow degrees of the northern side and encroaching on
285
00:19:28.559 --> 00:19:32.599
the west side, and so round by the south, by
286
00:19:32.720 --> 00:19:36.359
the east again to the north. In this case, the
287
00:19:36.480 --> 00:19:40.240
chute would remain always bowed, with the painted line appearing
288
00:19:40.319 --> 00:19:44.359
on the several above specified surfaces, and with the point
289
00:19:44.400 --> 00:19:47.960
of the chute successively directed to each point of the confass.
290
00:19:48.799 --> 00:19:52.000
In fact, we should have the exact kind of movement
291
00:19:52.079 --> 00:19:56.680
performed by the revolving chutes of twining plants. It must
292
00:19:56.759 --> 00:19:59.920
not be supposed that the revolving movement is as redu
293
00:20:00.359 --> 00:20:04.160
as that given in the above illustration. In many cases
294
00:20:04.279 --> 00:20:07.920
the tip describes an ellipse, even a very narrow ellipse.
295
00:20:08.480 --> 00:20:12.039
To recur once again to our illustration. If we suppose
296
00:20:12.119 --> 00:20:15.880
only the northern and southern surfaces of the sapling alternatively
297
00:20:16.240 --> 00:20:20.599
to grow, the summit would describe a simple arc. If
298
00:20:20.680 --> 00:20:23.960
the growth first traveled a very little to the western face,
299
00:20:24.279 --> 00:20:27.279
and during the return of very little to the eastern face,
300
00:20:27.720 --> 00:20:31.160
a narrow ellipse would be described, and the sapling would
301
00:20:31.200 --> 00:20:34.200
be straight as it passed to and fro through the
302
00:20:34.279 --> 00:20:38.400
intermediate space. And a complete straightening of the chute may
303
00:20:38.440 --> 00:20:43.279
often be observed. In revolving plants, the movement is frequently
304
00:20:43.359 --> 00:20:46.240
such that three sides of the chute may seem to
305
00:20:46.279 --> 00:20:50.079
be growing in due order more rapidly than the remaining side,
306
00:20:50.279 --> 00:20:53.480
so that a semi circle instead of a circle is described,
307
00:20:53.880 --> 00:20:57.480
the shute becoming straight and upright during half of its course.
308
00:20:58.759 --> 00:21:03.160
When a revolving shoot consists of several internodes, the lower
309
00:21:03.200 --> 00:21:06.559
ones bend together at the same rate, but one or
310
00:21:06.640 --> 00:21:10.880
two of the terminal ones bend at a slower rate. Hence,
311
00:21:11.160 --> 00:21:14.559
though at times all the internodes are in the same direction,
312
00:21:15.160 --> 00:21:20.000
other times the shute is rendered slightly serpentine. The rate
313
00:21:20.079 --> 00:21:22.880
of revolution of the whole shoot, if judged by the
314
00:21:22.920 --> 00:21:26.839
movement of the extreme tip, is thus at times accelerated
315
00:21:27.000 --> 00:21:31.960
or retarded. One other point must be noticed. Authors have
316
00:21:32.039 --> 00:21:35.160
observed that the end of the shoote in many twining
317
00:21:35.200 --> 00:21:39.599
plants is completely hooked. This is very general. For instance,
318
00:21:39.839 --> 00:21:44.720
with the Asclepidacia. The hooked tip in all the cases
319
00:21:44.799 --> 00:21:53.559
observed by me viz. The Ceropagia spherostema, chlodendron, Wisteria, Stephania, Acabia,
320
00:21:53.880 --> 00:21:57.799
and Siphomerus has exactly the same kind of movement as
321
00:21:57.839 --> 00:22:01.160
the other internodes. For a line painted on the convex
322
00:22:01.279 --> 00:22:05.799
surface first becomes lateral and then concave. But owing to
323
00:22:05.839 --> 00:22:09.039
the youth of these terminal internodes, the reversal of the
324
00:22:09.079 --> 00:22:12.799
hook is a slower process than that of the revolving movement.
325
00:22:13.799 --> 00:22:17.559
This strongly marked tendency in the young terminal and flexible
326
00:22:17.599 --> 00:22:21.079
internodes to bend in a greater degree or more abruptly
327
00:22:21.119 -->
00:22:24.279
than the other internodes is of service to the plant,
328
00:22:24.640 --> 00:22:27.720
for not only does the hook thus formed sometimes serve
329
00:22:27.839 --> 00:22:31.359
to catch a support, but and this seems to be
330
00:22:31.440 --> 00:22:34.839
much more important, it causes the extremity of the shoots
331
00:22:34.920 --> 00:22:38.359
to embrace the support much more closely than it could
332
00:22:38.480 --> 00:22:41.920
otherwise have done. And this aids in preventing the stem
333
00:22:41.960 --> 00:22:45.319
from being blown away during windy weather. As I have
334
00:22:45.599 --> 00:22:52.119
many times observed in Lorniseia brachipoda, the hook only straightens
335
00:22:52.119 --> 00:22:56.920
itself periodically and never becomes reversed. I will not assert
336
00:22:57.000 --> 00:23:00.400
that the tips of all twining plants, when hooked, reverse
337
00:23:00.480 --> 00:23:04.440
themselves or become periodically straight in the manner just described,
338
00:23:04.880 --> 00:23:07.799
for the hooked form may in some cases be permanent
339
00:23:08.119 --> 00:23:10.960
and be due to the manner of growth of the species,
340
00:23:11.279 --> 00:23:14.279
as with the tips of the shoots of the common vine,
341
00:23:14.519 --> 00:23:18.960
and more plainly with those of Sissa's discolor plants, which
342
00:23:19.000 --> 00:23:23.920
are not spiral twiners. The first purpose of the spontaneous
343
00:23:24.000 --> 00:23:29.000
revolving movement, or more strictly speaking of the continuous boeing movement,
344
00:23:29.160 --> 00:23:32.759
directed successfully to all points of the compass is as
345
00:23:32.880 --> 00:23:36.720
molar has remarked to favor the shoe finding a support.
346
00:23:37.160 --> 00:23:41.079
This is admirably affected by the revolutions carried on night
347
00:23:41.160 --> 00:23:44.480
and day, a wider and wider circle being swept as
348
00:23:44.480 --> 00:23:48.839
the shute increases in length. This movement likewise explains how
349
00:23:48.839 --> 00:23:51.960
the plants twine. For when a revolving chute meets with
350
00:23:52.000 --> 00:23:55.680
a support, its motion is necessarily arrested at the point
351
00:23:55.759 --> 00:23:59.599
of contact, but the free projecting part goes on revolving.
352
00:24:00.400 --> 00:24:03.480
As this continues, higher and higher points are brought into
353
00:24:03.480 --> 00:24:07.160
contact with the support and are arrested, and so onwards
354
00:24:07.200 --> 00:24:11.119
to the extremity, and thus the chute winds round its support.
355
00:24:11.920 --> 00:24:14.640
When the chute follows the sun in its revolving course,
356
00:24:14.680 --> 00:24:17.759
it winds round the support from right to left, the
357
00:24:17.799 --> 00:24:20.799
support being supposed to stand in front of the beholder.
358
00:24:21.799 --> 00:24:25.160
When the chute revolves in an opposite direction, the line
359
00:24:25.200 --> 00:24:29.839
of winding is reversed. As each internode loses from age
360
00:24:29.920 --> 00:24:33.759
its power of revolving, it likewise loses its power of
361
00:24:33.839 --> 00:24:37.559
spirally twining. If a man swings a rope round his
362
00:24:37.680 --> 00:24:41.039
head and end hits a stick, it will coil round
363
00:24:41.119 --> 00:24:43.880
the stick according to the direction of the swinging movement.
364
00:24:44.519 --> 00:24:47.400
So it is with a twining plant, a line of
365
00:24:47.440 --> 00:24:51.119
growth traveling round the free part of the chute, causing
366
00:24:51.119 --> 00:24:54.599
it to bend towards the opposite side, and this replaces
367
00:24:54.640 --> 00:24:58.839
the momentum of the free end of the rope. All
368
00:24:58.880 --> 00:25:02.440
the authors, except Palm and Moule, who have discussed the
369
00:25:02.480 --> 00:25:06.119
spral twining of plants, maintain that such plants have a
370
00:25:06.240 --> 00:25:11.000
natural tendency to grow spirally. Mole believes page one twelve
371
00:25:11.480 --> 00:25:15.319
that twining plants have a dull kind of irritability, so
372
00:25:15.359 --> 00:25:18.640
that they bend towards any object which they touch, but
373
00:25:18.759 --> 00:25:23.920
this is denied by Palm. Even before reading Mull's interesting Treaties,
374
00:25:24.200 --> 00:25:27.359
this view seemed to me so probable that I tested
375
00:25:27.400 --> 00:25:30.240
it in every way that I could, but always with
376
00:25:30.400 --> 00:25:34.519
a negative result. I rubbed many shoots much harder than
377
00:25:34.640 --> 00:25:37.839
is necessary to excite movement in any tendril or in
378
00:25:38.039 --> 00:25:41.960
the footstock of any leaf climber, but without any effect.
379
00:25:42.640 --> 00:25:45.759
I then tied a light forked twig to a shoot
380
00:25:45.799 --> 00:25:50.839
of a hop A Seropagia, spherostema and ad hatota, so
381
00:25:51.160 --> 00:25:53.839
that the fork pressed on one side alone of the
382
00:25:53.880 --> 00:25:58.319
shoot and revolved with it. I purposely selected some very
383
00:25:58.359 --> 00:26:02.279
slow revolvers, as its seemed most likely that these would
384
00:26:02.279 --> 00:26:06.559
profit most from possessing irritability, But in no case was
385
00:26:06.640 --> 00:26:11.720
any effect produced. Moreover, when a shoot winds round a support,
386
00:26:12.039 --> 00:26:16.240
the winding movement is always slower, as we shall immediately see,
387
00:26:16.599 --> 00:26:21.039
than whilst it revolves freely and touches nothing. Hence, I
388
00:26:21.079 --> 00:26:25.279
conclude that twining stems are not irritable, and indeed it
389
00:26:25.359 --> 00:26:28.480
is not probable that they should be so, as nature
390
00:26:28.519 --> 00:26:34.440
always economizes her means, and irritability would have been superfluous. Nevertheless,
391
00:26:34.480 --> 00:26:37.680
I do not wish to assert that they are never irritable,
392
00:26:38.200 --> 00:26:40.880
For the
growing axis of the leaf climbing but not
393
00:26:40.960 --> 00:26:46.720
spirally dwining the phospermum scandas is certainly irritable. But this
394
00:26:46.799 --> 00:26:50.839
case gives me confidence that ordinary twiners do not possess
395
00:26:50.920 --> 00:26:53.960
any such quality. For directly after putting a stick to
396
00:26:54.000 --> 00:26:58.319
the Lofopermum, I saw that it behaved differently from a
397
00:26:58.359 --> 00:27:02.519
true twiner or any other leaf climber. The belief that
398
00:27:02.640 --> 00:27:06.559
twiners have a natural tendency to grow spirally probably arose
399
00:27:06.640 --> 00:27:09.720
from their assuming a spiral form when round round a
400
00:27:09.799 --> 00:27:14.880
support and from the extremity, even whilst remaining free. Sometimes
401
00:27:14.960 --> 00:27:20.160
assuming this form. The free internodes of vigorously growing plants,
402
00:27:20.240 --> 00:27:23.759
when they cease to evolve, become straight and show no
403
00:27:23.920 --> 00:27:28.240
tendency to spiral. But when a shoot has nearly ceased
404
00:27:28.279 --> 00:27:31.920
to grow, or when the plant is unhealthy, the extremity
405
00:27:32.039 --> 00:27:36.079
does occasionally become spiral. I have seen this in a
406
00:27:36.200 --> 00:27:39.160
remarkable manner with the ends of the shoots of the
407
00:27:39.279 --> 00:27:43.960
Stantonia and of the allied Acaba, which became wound up
408
00:27:44.119 --> 00:27:48.240
into a close spire, just like a tendril, and this
409
00:27:48.440 --> 00:27:51.960
was apt to occur after some small, ill formed leaves
410
00:27:51.960 --> 00:27:56.000
had perished. The explanation I believe is that in such
411
00:27:56.079 --> 00:27:59.599
cases the lower part of the terminal internodes vary gradually
412
00:27:59.680 --> 00:28:03.200
and so accessibly lose their power of movement, whilst the
413
00:28:03.240 --> 00:28:07.759
portions just above move onwards and in their turn become motionless,
414
00:28:08.200 --> 00:28:12.680
and this ends in forming an irregular spire. When a
415
00:28:12.720 --> 00:28:16.480
revolving shoot strikes a stick, it winds round it rather
416
00:28:16.519 --> 00:28:20.039
more slowly than it revolves. For instance, a shoot of
417
00:28:20.079 --> 00:28:24.680
the Ceropegia revolved in six hours, but took nine hours
418
00:28:24.799 --> 00:28:28.319
thirty minutes to make one complete spire round A stick
419
00:28:29.240 --> 00:28:34.160
Astrolochia gigyas revolved in about five hours, but took nine
420
00:28:34.200 --> 00:28:38.319
hours fifteen minutes to complete its fire. This, I presume
421
00:28:38.519 --> 00:28:41.680
is due to the continued disturbance of the impelling force
422
00:28:41.799 --> 00:28:45.720
by the arrestment of the movement at successive points. And
423
00:28:45.759 --> 00:28:49.599
we shall hereafter see that even shaking a plant retards
424
00:28:49.720 --> 00:28:53.920
the revolving movement. The terminal internodes of a
long, much
425
00:28:53.960 --> 00:28:58.359
inclined revolving shoot of the ceropagia, after they had wound
426
00:28:58.559 --> 00:29:02.240
round a stick, always slipped up it so as to
427
00:29:02.279 --> 00:29:05.400
render the spire more open than it was at first,
428
00:29:05.799 --> 00:29:08.559
and this was probably in part due to the force
429
00:29:08.599 --> 00:29:12.640
which caused the revolutions, being now almost freed from the
430
00:29:12.640 --> 00:29:17.359
constraint of gravity and allowed to act freely with the wisteria.
431
00:29:17.480 --> 00:29:21.119
On the other hand, a long horizontal shoote wound itself
432
00:29:21.160 --> 00:29:25.400
at first into a very close spire which remained unchanged,
433
00:29:25.759 --> 00:29:30.000
but subsequently, as the chute twined spirally up its support,
434
00:29:30.400 --> 00:29:34.119
it made a much more open spire with all the
435
00:29:34.200 --> 00:29:37.559
many plants which were allowed freely to assent a support.
436
00:29:37.880 --> 00:29:41.680
The terminal internodes made at first a close spire, and
437
00:29:41.799 --> 00:29:44.799
this during windy weather, served to keep the shootes in
438
00:29:44.880 --> 00:29:49.119
close contact with their support. But as the penultimate internodes
439
00:29:49.160 --> 00:29:52.720
grew in length, they pushed themselves up for a considerable
440
00:29:52.799 --> 00:29:56.680
space ascertained by colored marks on the chute and on
441
00:29:56.720 --> 00:30:00.880
the support round the stick, and the spire became more open.
442
00:30:02.039 --> 00:30:05.599
It follows from this latter fact that the position occupied
443
00:30:05.599 --> 00:30:08.960
by each leaf with respect to its support depends on
444
00:30:09.039 --> 00:30:12.000
the growth of the internodes after they have become spirally
445
00:30:12.200 --> 00:30:16.000
wound round it. I mention this on account of an
446
00:30:16.039 --> 00:30:20.039
observation by Palm page thirty four, who states that the
447
00:30:20.079 --> 00:30:22.920
opposite leaves of the hop always stand in a row
448
00:30:23.079 --> 00:30:26.519
exactly over one another on the same side of the
449
00:30:26.559 --> 00:30:31.519
supporting stick, whatever its thickness may be. My sons visited
450
00:30:31.559 --> 00:30:34.319
a hop field for me and reported that though they
451
00:30:34.400 --> 00:30:38.039
generally found the points of insertion of the leaves standing
452
00:30:38.079 --> 00:30:40.759
over each other for a space of two or three
453
00:30:40.799 --> 00:30:44.279
feet in height, yet this never occurred up the whole
454
00:30:44.480 --> 00:30:48.119
length of the pole, the points of insertion forming as
455
00:30:48.240 --> 00:30:53.000
might have been expected on irregular spire. Any irregularity in
456
00:30:53.039 --> 00:30:56.960
the pole entirely destroyed the regularity of position of the
457
00:30:57.079 --> 00:31:00.640
leaves From casual inspection, it appeared to me that the
458
00:31:00.680 --> 00:31:05.400
opposite leaves of Thunbergia alatta were arranged in lines up
459
00:31:05.440 --> 00:31:09.039
the sticks round which they had twined. Accordingly, I raised
460
00:31:09.079 --> 00:31:12.079
a dozen plants and gave them sticks of various thicknesses,
461
00:31:12.160 --> 00:31:16.160
as well as string to twine round. And in this case,
462
00:31:16.480 --> 00:31:19.559
one alone out of the dozen had its leaves arranged
463
00:31:19.559 --> 00:31:24.319
in a perpendicular line. I conclude therefore, Polln's statement is
464
00:31:24.480 --> 00:31:28.960
not quite accurate. The leaves of different twining plants are
465
00:31:29.039 --> 00:31:33.839
arranged on the stem before it has twined, alternately or oppositely,
466
00:31:34.200 --> 00:31:37.680
or in aspire. In the latter case, the line of
467
00:31:37.759 --> 00:31:42.240
insertion of the leaves and the course of the revolutions coincide.
468
00:31:42.400 --> 00:31:46.240
This fact has been well shown by Dutrochi, who found
469
00:31:46.400 --> 00:31:52.000
different individuals of Solanum dolcamara twining in opposite directions, and
470
00:31:52.079 --> 00:31:55.440
these had their leaves in each case spirally arranged in
471
00:31:55.519 --> 00:31:59.599
the same direction. A dense whirl of many leaves would
472
00:31:59.599 --> 00:32:04.079
apparently be incommodious for a twining plant, and some authors
473
00:32:04.119 --> 00:32:08.039
assert that none have their leaves thus arranged. But a
474
00:32:08.079 --> 00:32:12.799
twining ciphomeris has whirls of three leaves. If a stick
475
00:32:13.079 --> 00:32:17.119
which has arrested a revolving chute, but has not as
476
00:32:17.200 --> 00:32:21.599
yet been encircled, be suddenly taken away. The chute generally
477
00:32:21.640 --> 00:32:25.599
springs forward, showing that it was pressed with some force
478
00:32:25.759 --> 00:32:30.200
against the stick. After a chute has wound round a stick,
479
00:32:30.559 --> 00:32:33.039
if this be withdrawn, it retains for a time its
480
00:32:33.079 --> 00:32:37.559
spiral form. It then straightens itself and again commences to revolve.
481
00:32:38.480 --> 00:32:42.720
The long, much inclined shoot of the ceropegia previously alluded
482
00:32:42.759 --> 00:32:48.319
to offered some curious peculiarities. The lower and older internodes,
483
00:32:48.359 --> 00:32:52.440
which continued to revolve, were incapable on repeated trials of
484
00:32:52.559 --> 00:32:56.039
twining round a thin stick, showing that although the power
485
00:32:56.079 --> 00:32:59.359
of movement was retained, this was not sufficient to enable
486
00:32:59.359 --> 00:33:02.839
the plant to I then moved the stick to a
487
00:33:02.880 --> 00:33:05.839
greater distance, so that it was struck by a point
488
00:33:05.960 --> 00:33:08.359
two and one half inches from the extremity of the
489
00:33:08.400 --> 00:33:12.599
penultimate internode, and it was then neatly encircled by this
490
00:33:12.720 --> 00:33:17.319
part of the penultimate and by the ultimate internode. After
491
00:33:17.440 --> 00:33:20.839
leaving the spirally wound shoote for eleven hours, I quietly
492
00:33:20.920 --> 00:33:23.599
withdrew the stick, and in the course of the day
493
00:33:23.720 --> 00:33:27.920
the curled portion straightened itself and recommenced revolving, But the
494
00:33:27.960 --> 00:33:31.359
lower and not curled portion of the penultimate internode did
495
00:33:31.400 --> 00:33:34.799
not move, a sort of hinge separating the moving and
496
00:33:34.880 --> 00:33:39.119
motionless part of the same internode. After a few days, however,
497
00:33:39.400 --> 00:33:42.480
I found that this lower part had likewise recovered its
498
00:33:42.559 --> 00:33:46.839
revolving power. These several facts show that the power of
499
00:33:47.000 --> 00:33:50.240
movement is not immediately lost in the arrested portion of
500
00:33:50.279 --> 00:33:54.519
a revolving shoot, and that after being temporarily lost, it
501
00:33:54.640 --> 00:33:58.000
can be recovered. When a shoot has remained for a
502
00:33:58.039 --> 00:34:02.759
considerable time round a support, it permanently retains its spiral form,
503
00:34:03.160 --> 00:34:06.720
even when the support is removed. When a tall stick
504
00:34:06.839 --> 00:34:09.440
was placed so as to arrest the lower and rigid
505
00:34:09.480 --> 00:34:13.000
internodes of the serapagia at the distance at first of
506
00:34:13.039 --> 00:34:16.440
fifteen and then of twenty one inches from the center
507
00:34:16.480 --> 00:34:20.800
of revolution, the straight chute slowly and gradually slid up
508
00:34:20.840 --> 00:34:24.480
the stick so as to become more and more highly inclined,
509
00:34:24.840 --> 00:34:28.440
but it did not pass over the summit. Then, after
510
00:34:28.480 --> 00:34:32.280
an interval sufficient to have allowed a semi rotation, the
511
00:34:32.360 --> 00:34:36.360
chute suddenly bounded from the stick and fell over to
512
00:34:36.400 --> 00:34:40.159
the opposite side or point of the compass and reassumed
513
00:34:40.199 --> 00:34:45.559
its previous slight inclination. It now recommenced revolving in its
514
00:34:45.679 --> 00:34:49.360
usual course, so that after a semi revolution, it again
515
00:34:49.519 --> 00:34:52.960
came into contact with the stick, again slid up it,
516
00:34:53.199 --> 00:34:56.280
and again bounded from it and fell over to the
517
00:34:56.320 --> 00:34:59.840
opposite side. This movement of the chute had a very
518
00:35:00.239 --> 00:35:03.360
appearance as if it were disgusted with its failure, but
519
00:35:03.519 --> 00:35:07.440
was resolved to try again. We shall, I think, understand
520
00:35:07.480 --> 00:35:10.639
this movement by considering the former illustration of the sapling,
521
00:35:10.960 --> 00:35:13.519
in which the growing surface was supposed to creep ground
522
00:35:13.519 --> 00:35:16.880
from the northern by the western to the southern face,
523
00:35:17.199 --> 00:35:20.199
and thence back again by the eastern to the northern face,
524
00:35:20.559 --> 00:35:25.280
successfully bowing the sapling in all directions. Now with serapegia,
525
00:35:25.719 --> 00:35:28.400
the stick being placed to the south of the chute
526
00:35:28.559 --> 00:35:31.760
and in contact with it. As soon as the circulatory
527
00:35:31.840 --> 00:35:35.679
growth reached the western surface, no effect would be produced
528
00:35:36.039 --> 00:35:39.239
except that the chute would be pressed firmly against the stick.
529
00:35:40.079 --> 00:35:43.039
But as soon as growth on the southern surface began,
530
00:35:43.440 --> 00:35:46.920
the chute would be slowly dragged with sliding movement up
531
00:35:46.960 --> 00:35:50.800
the stick, And then as soon as the eastern growth commenced,
532
00:35:50.920 --> 00:35:53.199
the chute would be drawn from the stick, and its weight,
533
00:35:53.320 --> 00:35:56.840
coinciding with the effects of the changed surface of growth,
534
00:35:57.039 --> 00:36:00.039
would cause it to suddenly fall to the opposite side,
535
00:36:00.239 --> 00:36:05.239
reassuming its previous slight inclination, and the ordinary revolving movement
536
00:36:05.559 --> 00:36:08.760
would then go on as before. I have described this
537
00:36:08.920 --> 00:36:12.199
curious case with some care, because it first led me
538
00:36:12.320 --> 00:36:16.199
to understand the order in which, as I then thought,
539
00:36:16.519 --> 00:36:20.039
the surfaces contracted, but in which, as we now know
540
00:36:20.159 --> 00:36:23.559
from Sacks and two de vries, they grow for a
541
00:36:23.599 --> 00:36:27.400
time rapidly, thus causing the chute to bow towards the
542
00:36:27.480 --> 00:36:32.440
opposite side. The view just given further explains, as I
543
00:36:32.559 --> 00:36:36.480
believe a fact observed by Mole page one thirty five,
544
00:36:37.039 --> 00:36:40.360
namely that a revolving chute, though it will twine round
545
00:36:40.400 --> 00:36:43.280
an object as thin as a thread, cannot do so
546
00:36:43.480 --> 00:36:47.599
round a thick support. I placed some long revolving shoots
547
00:36:47.599 --> 00:36:50.679
of a westeria close to a post between five and
548
00:36:50.800 --> 00:36:54.360
six inches in diameter, but though aided by me in
549
00:36:54.440 --> 00:36:58.400
many ways, they could not wind round it. This apparently
550
00:36:58.559 --> 00:37:01.800
was due to the flexure of shute whilst winding round
551
00:37:01.880 --> 00:37:05.719
an object so gently curved as this post. Not being
552
00:37:05.719 --> 00:37:08.519
sufficient to hold the chute to its place, when the
553
00:37:08.519 --> 00:37:12.000
growing surface crept round to the opposite surface of the chute,
554
00:37:12.320 --> 00:37:16.440
so that it was withdrawn at each revolution from its support.
555
00:37:17.880 --> 00:37:21.000
When a free shoot has grown far
beyond its support,
556
00:37:21.360 --> 00:37:24.800
it sinks downwards from its weight, as already explained in
557
00:37:24.840 --> 00:37:29.360
the case of the hop with the revolving extremity turned upwards.
558
00:37:30.079 --> 00:37:33.000
If the support be not lofty, the chute falls to
559
00:37:33.039 --> 00:37:37.119
the ground, and, resting there the extremity rises up. Sometimes
560
00:37:37.159 --> 00:37:41.000
several shoots, when flexible, twined together into a cable and
561
00:37:41.039 --> 00:37:45.480
thus support one another. Single thin, depending chutes, such as
562
00:37:45.519 --> 00:37:49.719
those of the Solia dromondai, will turn abruptly backwards and
563
00:37:49.880 --> 00:37:54.880
wind up on themselves. The greater number of the depending chutes, however,
564
00:37:55.199 --> 00:37:59.800
of one twining plant, the Hibertia dentata, showed but little
565
00:38:00.559 --> 00:38:05.159
to turn upwards. In other cases, as with the Cryptostagia
566
00:38:05.199 --> 00:38:10.159
grande flora, several internodes which were at first flexible and revolved,
567
00:38:10.320 --> 00:38:13.159
if they did not succeed in twining round to support,
568
00:38:13.519 --> 00:38:18.480
become quite rigid and supporting themselves upright, carried on their summits.
569
00:38:18.599 --> 00:38:23.000
The younger revolving internodes here will be a convenient place
570
00:38:23.039 --> 00:38:26.119
to give a table showing the direction and rate of
571
00:38:26.239 --> 00:38:30.480
movement of several twining plants, with a few appended remarks.
572
00:38:31.119 --> 00:38:35.159
These plants are arranged according to Lindley's Vegetable Kingdom of
573
00:38:35.239 --> 00:38:38.480
eighteen fifty three, and they have been selected from all
574
00:38:38.559 --> 00:38:41.320
parts of the series so as to show that all
575
00:38:41.440 --> 00:38:45.199
kinds behave in a nearly uniform manner. The rate of
576
00:38:45.360 --> 00:38:54.280
revolution of the various twining plants. Acrotylodons, Negodium scandas Palapodipia
577
00:38:54.679 --> 00:38:59.480
moves against the sun. June eighteenth, first circle was made
578
00:38:59.639 --> 00:39:05.000
in six hours zero minutes. Eighteenth second circle six hours
579
00:39:05.079 --> 00:39:10.679
fifteen minutes, late in the evening. Nineteenth third cycle five
580
00:39:10.840 --> 00:39:16.320
hours thirty two minutes, very hot day, nineteenth fourth circle
581
00:39:16.840 --> 00:39:23.239
five hours zero minutes, very hot day. Twenty fifth circle
582
00:39:23.599 --> 00:39:29.480
six hours zero minutes. The Dodium articulatum moves against the sun.
583
00:39:30.199 --> 00:39:35.159
July nineteenth. First circle was made in sixteen hours thirty
584
00:39:35.199 --> 00:39:41.360
minutes shoot very young. July twentieth, second circle fifteen hours
585
00:39:41.480 --> 00:39:47.000
zero minutes. July twenty first third circle eight hours zero minutes.
586
00:39:47.679 --> 00:39:54.239
July twenty second fourth circle ten hours thirty minutes monocotoldons
587
00:39:55.079 --> 00:40:00.639
Ruscus androgynus. The leacia, placed in the hot house, moves
588
00:40:00.800 --> 00:40:05.320
against the sun. May twenty fourth, first circle was made
589
00:40:05.440 --> 00:40:10.360
in six hours fourteen minutes. Shoot very young. May twenty fifth.
590
00:40:10.440 --> 00:40:15.039
Second circle two hours twenty one minutes. May twenty fifth,
591
00:40:15.079 --> 00:40:19.920
third circle three hours thirty seven minutes. May twenty fifth,
592
00:40:20.039 --> 00:40:24.760
fourth circle three hours twenty two minutes. May twenty sixth,
593
00:40:25.000 --> 00:40:30.039
fifth circle two hours fifty minutes. May twenty seventh. Sixth
594
00:40:30.079 --> 00:40:34.920
circle three hours fifty two minutes. May twenty seventh, seventh
595
00:40:34.960 --> 00:40:40.920
circle four hours eleven minutes. Asparagus unnamed species from q
596
00:40:41.639 --> 00:40:47.000
Leasia moves against the sun, placed in hot house. December
597
00:40:47.000 --> 00:40:50.880
twenty sixth. First circle was made in five hour zero minutes.
598
00:40:51.320 --> 00:40:56.840
December twenty seventh, second circle five hours forty minutes. Temas
599
00:40:56.840 --> 00:41:02.480
communists dioscore ci, a young shoot from a tuber in
600
00:41:02.559 --> 00:41:07.559
a pot placed in the greenhouse, follows the sun. July seventh.
601
00:41:07.639 --> 00:41:11.920
First circle was made in three hours ten minutes. July seventh.
602
00:41:12.039 --> 00:41:16.639
Second circle two hours thirty eight minutes. July eighth, third
603
00:41:16.760 --> 00:41:22.159
circle three hours five minutes. July eighth, fourth circle two
604
00:41:22.239 --> 00:41:26.920
hours for fifty six minutes. July eighth fifth circle two
605
00:41:27.000 --> 00:41:32.079
hours thirty minutes. July eighth, sixth circle two hours thirty minutes.
606
00:41:33.280 --> 00:41:39.159
Lapageria rosea. The le ciersai in greenhouse follows the sun.
607
00:41:40.000 --> 00:41:44.800
March ninth. First circle was made in twenty six hours
608
00:41:44.840 --> 00:41:51.000
fifteen minutes. Shoot Young March tenth. Semicircle eight hours fifteen minutes,
609
00:41:51.639 --> 00:41:57.280
March eleventh, second circle eleven hours zero minutes, March twelfth,
610
00:41:57.320 --> 00:42:02.679
third circle fifteen hours thirty minutes. March thirteenth, fourth circle
611
00:42:02.840 --> 00:42:08.639
fourteen hours fifteen minutes. March sixteenth, fifth circle eight hours
612
00:42:08.760 --> 00:42:11.800
forty minutes when placed in the hot house, but the
613
00:42:11.840 --> 00:42:18.000
next day the chuote remained stationary. Roxburghia vire deflora roxburg
614
00:42:18.079 --> 00:42:22.639
Acia moves against the sun. It completed a circle in
615
00:42:22.679 --> 00:42:30.880
about twenty four hours. Dicotylodons Homolus upulus urtipasia follows the sun.
616
00:42:31.559 --> 00:42:34.400
The plant was kept in a room
during warm weather.
617
00:42:35.360 --> 00:42:39.039
April ninth. Two circles were made in four hours sixteen minutes.
618
00:42:39.199 --> 00:42:45.639
August thirteenth. Third circle was two hours zero minutes. August fourteenth,
619
00:42:45.800 --> 00:42:51.159
fourth circle two hours twenty minutes. August fourteenth, fifth circle
620
00:42:51.239 --> 00:42:56.679
two hours sixteen minutes. August fourteenth. Sixth circle two hours
621
00:42:56.719 --> 00:43:01.840
two minutes. August fourteenth, seventh circle two hours zero minutes.
622
00:43:02.400 --> 00:43:07.679
August fourteenth, eighth circle two hours four minutes. With the
623
00:43:07.760 --> 00:43:10.920
hop a semi circle was performed in traveling from the
624
00:43:11.039 --> 00:43:14.719
light in one hour thirty three minutes, in traveling to
625
00:43:14.840 --> 00:43:18.280
the light in one hour thirteen minutes. Difference of rate
626
00:43:18.519 --> 00:43:26.280
twenty minutes. Akebia Quinata Lardza Belesia placed in hothouse moves
627
00:43:26.360 --> 00:43:30.760
against the sun. March seventeenth. First circle was made in
628
00:43:30.880 --> 00:43:35.800
four hours zero minutes. Shoot Young March eighteenth. Second circle
629
00:43:36.199 --> 00:43:40.320
one hour forty minutes, March eighteenth, third circle one hour
630
00:43:40.440 --> 00:43:45.920
thirty minutes, March nineteenth, fourth circle one hour forty five minutes.
631
00:43:47.000 --> 00:43:54.280
Stontonia Latifolia Lardze Ballesia, placed in hot house moves against
632
00:43:54.280 --> 00:43:58.039
the sun. March twenty eighth. First circle was made in
633
00:43:58.199 --> 00:44:02.840
three hours thirty minutes. March twenty ninth, second circle three
634
00:44:02.880 --> 00:44:11.599
hours forty five minutes. Spero Stemma marratum Shazendresier follows the sun.
635
00:44:12.800 --> 00:44:16.280
August fifth first circle was made in about twenty four
636
00:44:16.320 --> 00:44:20.360
hour zero minutes. August fifth second circle was made in
637
00:44:20.440 --> 00:44:27.159
eighteen hours thirty minutes. Stefania Rotunda Menace Permecier moves against
638
00:44:27.239 --> 00:44:31.280
the sun. May twenty seventh. First circle was made in
639
00:44:31.599 --> 00:44:36.840
five hours five minutes. May thirty, second circle seven hours
640
00:44:37.039 --> 00:44:41.800
six minutes, June second, third circle was made in five
641
00:44:41.880 --> 00:44:46.639
hours fifteen minutes, and June third fourth circle six hours
642
00:44:46.679 --> 00:44:53.639
twenty eight minutes. Trales brakistakes Malpigasia moves against the sun.
643
00:44:54.119 --> 00:44:56.920
One shoot made a circle in twelve hours and another
644
00:44:57.079 --> 00:45:00.280
in ten hours thirty minutes, but the next day, which
645
00:45:00.400 --> 00:45:03.400
was much colder, the first shoot took ten hours to
646
00:45:03.440 --> 00:45:09.880
perform only a semi circle. Gibertia dentata Dillameasia, placed in
647
00:45:09.960 --> 00:45:13.159
the hot house, followed the sun and made May eighteenth
648
00:45:13.480 --> 00:45:16.920
a circle in seven hours twenty minutes. On the nineteenth,
649
00:45:17.039 --> 00:45:20.480
reversed its course and moved against the sun and made
650
00:45:20.519 --> 00:45:24.400
a circle in seven hours. On the twentyth, moved against
651
00:45:24.440 --> 00:45:27.400
the sun one third of a circle, then stood still.
652
00:45:28.119 --> 00:45:31.000
On the twenty sixth, followed the sun for two thirds
653
00:45:31.039 --> 00:45:33.760
of a cycle, and then returned to its starting point,
654
00:45:34.199 --> 00:45:37.760
taking for this double course eleven hours forty six minutes.
655
00:45:39.079 --> 00:45:45.280
Solia rumandi pittosporesia moves against the sun. Kept in greenhouse.
656
00:45:45.960 --> 00:45:49.639
April fourth first circle was made in four hours twenty
657
00:45:49.639 --> 00:45:54.800
five minutes. April fifth, second circle eight hours zero minutes,
658
00:45:55.199 --> 00:46:00.519
very cold day, April sixth, third circle six hours twenty
659
00:46:00.559 --> 00:46:05.239
five minutes. April seventh, fourth circle seven hours five minutes.
660
00:46:06.079 --> 00:46:13.159
Polygonium jumietorum polygonacea. This case is taken from Dutoche, page
661
00:46:13.159 --> 00:46:17.679
two ninety nine. As I observed no allied plant follows
662
00:46:17.719 --> 00:46:21.039
the sun. Three shoots cut off a plant and placed
663
00:46:21.079 --> 00:46:24.679
in water, made circles in three hours ten minutes, five
664
00:46:24.719 --> 00:46:29.320
hours twenty minutes, and seven hours fifteen minutes with Sterea
665
00:46:29.480 --> 00:46:36.360
chenenisi lugomenose. In Greenhouse Moves against the Sun. May thirteenth,
666
00:46:36.440 --> 00:46:40.639
first circle was made in three hours five minutes. May thirteenth,
667
00:46:40.800 --> 00:46:45.840
second circle three hours twenty minutes. May sixteenth, third circle
668
00:46:46.000 --> 00:46:50.360
two hours five minutes. May twenty fourth, fourth circle three
669
00:46:50.400 --> 00:46:54.360
hours twenty one minutes. May twenty fifth, fifth circle two
670
00:46:54.360 --> 00:46:58.599
hours twenty seven minutes. May twenty fifth, sixth circle two
671
00:46:58.679 --> 00:47:05.039
hours thirty five minutes. Phasiolus vulgaris lugaminose a. In greenhouse
672
00:47:05.159 --> 00:47:09.440
Moves against the Sun, May, first circle was made in
673
00:47:09.719 --> 00:47:13.599
two hours zero minutes. May first second circle was made
674
00:47:13.679 --> 00:47:17.320
in one hour fifty five minutes. May first third circle
675
00:47:17.679 --> 00:47:22.880
was made in one hour fifty five minutes. Depladinae Europhylia
676
00:47:23.360 --> 00:47:29.119
applesinacea moves against the sun. April eighteenth. First circle was
677
00:47:29.159 --> 00:47:33.800
made in eight hours zero minutes. April nineteenth, second circle
678
00:47:33.920 --> 00:47:38.599
nine hours fifteen minutes.
April thirtieth, third circle nine hours
679
00:47:38.679 --> 00:47:46.039
forty minutes. The Platina crascinodia moves against the sun. May sixteenth.
680
00:47:46.119 --> 00:47:50.519
First circle was made in nine hours five minutes. July twentieth,
681
00:47:50.639 --> 00:47:55.480
second circle eight hours zero minutes. July twenty first third
682
00:47:55.519 --> 00:48:02.199
circle eight hours five minutes. Sirpegia gardineri a sclepidatia moves
683
00:48:02.239 --> 00:48:06.239
against the sun. Shoot very young two inches in length.
684
00:48:06.400 --> 00:48:09.960
First circle was performed in seven hours fifty five minutes.
685
00:48:10.519 --> 00:48:15.639
Shoot still young. Second circle seven hours zero minutes long shoot,
686
00:48:15.800 --> 00:48:20.800
third circle six hours thirty three minutes long shoot, fourth
687
00:48:20.840 --> 00:48:25.559
circle five hours fifteen minutes long shoot fifth circle six
688
00:48:25.639 --> 00:48:33.039
hours forty five minutes. Stephanotis Floribundai esclipidasia moves against the
689
00:48:33.079 --> 00:48:36.000
sun and made a circle in six hours forty minutes
690
00:48:36.320 --> 00:48:41.960
a second circle in about nine hours. Hoya Carnosa Esclipidasia
691
00:48:42.519 --> 00:48:46.239
made several circles in from sixteen hours to twenty two
692
00:48:46.280 --> 00:48:54.159
hours or twenty four hours. Apotmoyea perpore convolvolasia moves against
693
00:48:54.239 --> 00:48:58.840
the sun plant placed in room with lateral light. First
694
00:48:58.840 --> 00:49:03.360
circle was made into hours forty two minutes. Semicircle from
695
00:49:03.400 --> 00:49:06.719
the light in one hour fourteen minutes to the light
696
00:49:06.920 --> 00:49:11.360
one hour twenty eight minutes. Difference fourteen minutes. Second circle
697
00:49:11.480 --> 00:49:15.679
was made in two hours forty seven minutes. Semicircle from
698
00:49:15.719 --> 00:49:18.880
the light in one hour seventeen minutes to the light
699
00:49:19.000 --> 00:49:25.320
in one hour thirty minutes, difference thirteen minutes. Epomoyer ducundar
700
00:49:25.800 --> 00:49:30.719
convolvalasi moves against the sun. Placed in my study with
701
00:49:30.840 --> 00:49:35.519
windows facing the northeast weather hot. First circle was made
702
00:49:35.599 --> 00:49:39.079
in five hours thirty minutes. Semicircle from the light in
703
00:49:39.239 --> 00:49:41.960
four hours thirty minutes to the light in one hour
704
00:49:42.159 --> 00:49:46.920
zero minutes. Difference three hours thirty minutes. Second circle was
705
00:49:47.000 --> 00:49:50.360
made in five hours twenty minutes. Late in the afternoon,
706
00:49:50.599 --> 00:49:55.320
circle completed at six forty pm. Semicircle from the light
707
00:49:55.480 --> 00:49:58.079
in three hours fifty minutes to the light in one
708
00:49:58.159 --> 00:50:03.039
hour thirty minutes, different two hours twenty minutes. We have
709
00:50:03.239 --> 00:50:05.920
here a remarkable instance of the power of light in
710
00:50:06.039 --> 00:50:11.920
retarding and hastening to evolving movement. See Errata errata on
711
00:50:12.159 --> 00:50:16.880
pages twenty eight thirty two forty fifty three. Statements are
712
00:50:17.000 --> 00:50:20.360
made with reference to the supposed acceleration of the revolving
713
00:50:20.480 --> 00:50:24.719
movement toward alive. It appears from the observations given in
714
00:50:25.199 --> 00:50:28.239
the Power of Movement in Plants, page four fifty one
715
00:50:28.719 --> 00:50:34.000
that these conclusions were drawn from insufficient observations and are erroneous.
716
00:50:35.239 --> 00:50:42.039
Convolvous sepum large flowered cultivated variation moves against the sun.
717
00:50:42.880 --> 00:50:46.440
Two circles were made, each in one hour forty two minutes.
718
00:50:46.840 --> 00:50:50.599
Difference in semicircle from and to the light fourteen minutes.
719
00:50:51.360 --> 00:50:57.400
Riverea tilefolia convolvo racia moves against the sun. Made four
720
00:50:57.519 --> 00:51:01.199
revolutions in nine hours, so that on average each was
721
00:51:01.280 --> 00:51:07.960
performed in two hours fifteen minutes. Plumbago roseau genesia follows
722
00:51:08.039 --> 00:51:10.920
the sun. The shute did not begin to evolve until
723
00:51:11.000 --> 00:51:13.719
nearly a yard in the height. It then made a
724
00:51:13.800 --> 00:51:17.639
fine circle in ten hours forty five minutes. During the
725
00:51:17.719 --> 00:51:21.480
next few days it continued to move, but irregularly, and
726
00:51:21.639 --> 00:51:24.960
August fifteenth, the shoot followed during a period of ten
727
00:51:25.039 --> 00:51:29.679
hours forty minutes a long and deeply zigzagged course, and
728
00:51:29.840 --> 00:51:35.519
then made a broad ellipse. The figure apparently represented three ellipses,
729
00:51:35.639 --> 00:51:38.599
each of which averaged three hours thirty eight minutes for
730
00:51:38.760 --> 00:51:46.719
its completion. Jasminum Posiplorum Bentham Jasminecia moves against the Sun.
731
00:51:47.360 --> 00:51:50.199
A circle was made in seven hours fifteen minutes, and
732
00:51:50.280 --> 00:51:57.239
a second rather more quickly Plodendrum tomsonae Verbenacia follows the Sun.
733
00:51:57.920 --> 00:52:03.519
April twelfth. First circle was made in five hours forty
734
00:52:03.599 --> 00:52:07.760
five minutes. Shoot very young April fourteenth. Second circle three
735
00:52:07.840 --> 00:52:12.119
hours thirty minutes. April eighteenth, a semi circle five hour
736
00:52:12.320 --> 00:52:16.280
zero minutes directly after the plant was shaken on being moved.
737
00:52:16.960 --> 00:52:22.280
April nineteenth. Third circle three hours zero minutes. April twentieth,
738
00:52:22.400 --> 00:52:28.320
fourth circle four hours twenty minutes. Tacoma jasmina days bignier
739
00:52:28.559 --> 00:52:33.320
Za moves against the Sun. March seventeenth. First circle was
740
00:52:33.400 -->
00:52:37.480
made in six hours thirty minutes. March nineteenth. Second circle
741
00:52:37.599 --> 00:52:41.599
seven hours zero minutes. March twenty second third circle eight
742
00:52:41.719 --> 00:52:46.079
hours thirty minutes, very cold day, March twenty fourth fourth
743
00:52:46.199 --> 00:52:52.440
circle six hours forty five minutes from Bergia Alata Atanta
744
00:52:53.039 --> 00:52:57.480
moves against Sun April fourteenth. The first circle was made
745
00:52:57.559 --> 00:53:01.960
in three hours twenty minutes April eighteenth. Second circle two
746
00:53:02.039 --> 00:53:06.480
hours fifty minutes April eighteenth, third circle two hours fifty
747
00:53:06.519 --> 00:53:11.039
five minutes April eighteenth, fourth circle three hours fifty five minutes.
748
00:53:11.239 --> 00:53:18.159
Late in afternoon, at Hadota Psidernafolia, a cante ca follows
749
00:53:18.239 --> 00:53:21.679
the sun, a young shoot made a semicircle in twenty
750
00:53:21.719 --> 00:53:25.239
four hours. Subsequently, it made a circle in between forty
751
00:53:25.320 --> 00:53:28.559
hours and forty eight hours. Another shoot, however, made a
752
00:53:28.639 --> 00:53:33.199
circle in twenty six hours thirty minutes. The CanYa Scanden's
753
00:53:33.480 --> 00:53:38.719
Composita moves against the Sun March fourteenth. First circle was
754
00:53:38.880 --> 00:53:43.119
three hours ten minutes March fifteenth. Second circle three hours
755
00:53:43.199 --> 00:53:47.280
zero minutes March sixteenth. Third circle three hours zero minutes
756
00:53:47.840 --> 00:53:52.679
March seventeenth. Fourth circle three hours thirty three minutes April seventh.
757
00:53:52.960 --> 00:53:58.119
Fifth circle two hours fifty minutes April seventh. Sixth circle
758
00:53:58.440 --> 00:54:01.679
two hours forty minutes. The circle was made after a
759
00:54:01.800 --> 00:54:05.360
copious watering with cold water at forty seven degrees of
760
00:54:05.440 --> 00:54:12.639
fahrenheit combretum argentinum combretasia moves against the sun kept in
761
00:54:12.760 --> 00:54:16.920
hot house. January twenty fourth. First circle was made in
762
00:54:17.039 --> 00:54:20.039
two hours fifty five minutes, early in the morning, when
763
00:54:20.119 --> 00:54:24.440
the temperature of the house had fallen a little. January
764
00:54:24.559 --> 00:54:28.079
twenty fourth. Two circles each at an average of two
765
00:54:28.239 --> 00:54:32.440
hours twenty minutes. January twenty fifth, fourth circle two hours
766
00:54:32.480 --> 00:54:38.000
twenty five minutes. Cumbretum purpureum revolves not quite so quickly
767
00:54:38.119 --> 00:54:45.960
as see Argentineum lasa aratika los cia. Revolutions variable in
768
00:54:46.079 --> 00:54:50.599
their course. A plant which moved against the sun June twentieth.
769
00:54:50.719 --> 00:54:53.440
First circle was made in two hours thirty seven minutes.
770
00:54:53.599 --> 00:54:57.880
June twentieth. Second circle two hours thirteen minutes. June twentieth,
771
00:54:58.000 --> 00:55:01.880
third circle four hour zero minut June twenty first fourth
772
00:55:02.000 --> 00:55:05.800
circle two hours thirty five minutes. June twenty second fifth
773
00:55:05.880 --> 00:55:10.239
circle three hours twenty six minutes, June twenty third sixth
774
00:55:10.360 --> 00:55:15.239
circle three hours five minutes. Another plant which followed the
775
00:55:15.280 --> 00:55:20.079
sun in its revolutions July eleventh. First circle was made
776
00:55:20.159 --> 00:55:24.360
in one hour fifty one minutes very hot day, July eleventh.
777
00:55:24.480 --> 00:55:28.880
Second circle one hour forty six minutes. July eleventh, third
778
00:55:28.960 --> 00:55:33.840
circle one hour forty one minutes July eleventh, fourth circle
779
00:55:33.920 --> 00:55:37.920
one hour forty eight minutes, July twelfth, fifth circle two
780
00:55:38.000 --> 00:55:43.880
hours thirty five minutes. Cavanthos Elegance loay Cia follows the Sun.
781
00:55:44.800 --> 00:55:49.360
June thirteenth. First circle was made in one hour forty
782
00:55:49.440 --> 00:55:54.320
five minutes. June thirteenth, second circle one hour seventeen minutes,
783
00:55:54.760 --> 00:55:59.000
June fourteenth, third circle one hour thirty six minutes. June
784
00:55:59.119 --> 00:56:04.159
fourteenth circle one hour fifty nine minutes. June fourteenth, fifth
785
00:56:04.280 --> 00:56:11.079
circle two hours three minutes. Cyphomeris or lecontea unnamed species.
786
00:56:11.559 --> 00:56:17.480
Jinconesia follows the Sun. May twenty fifth. May twenty fifth
787
00:56:17.559 --> 00:56:21.239
semicircle was made in ten hours twenty seven minutes. Shoot
788
00:56:21.360 --> 00:56:26.360
extremely young. May twenty sixth first circle ten hours fifteen minutes,
789
00:56:26.400 --> 00:56:31.159
Shoot still young. May thirtieth, second circle eight hours fifty
790
00:56:31.199 --> 00:56:35.239
five minutes. June second third circle eight hours eleven minutes.
791
00:56:35.760 --> 00:56:40.079
June sixth, fourth circle six hours eight minutes. June eighth,
792
00:56:40.280 --> 00:56:43.920
fifth circle seven hours twenty minutes. Taken from the hothouse
793
00:56:44.000 --> 00:56:48.440
and replaced in a room in my house. June ninth,
794
00:56:48.599 --> 00:56:54.719
sixth circle eight hours thirty sixth minutes. Menetia by color chintrenasia.
795
00:56:55.400 --> 00:56:59.840
Young plant follows the sun. July seventh. Firth circle was
796
00:57:00.039 --> 00:57:04.119
made in six hours eighteen minutes. July eighth, second circle
797
00:57:04.280 --> 00:57:07.960
six hours fifty three minutes. July ninth, third circle six
798
00:57:08.079 --> 00:57:15.119
hours thirty minutes. Venosa brachipoda cepropoliaca follows the sun. Kept
799
00:57:15.159 --> 00:57:18.199
in a warm room in my house. April first first
800
00:57:18.360 --> 00:57:24.199
circle was made in nine hours ten minutes. About April second,
801
00:57:24.360 --> 00:57:28.719
second circle made in one hour twenty minutes. A distinct
802
00:57:28.800 --> 00:57:33.079
shoot very young on the same plant. April third, third
803
00:57:33.760 --> 00:57:39.119
shoot seven hours thirty minutes, April fourth, fourth circuit eight
804
00:57:39.239 --> 00:57:44.719
hours zero minutes. In this latter circle, the semicircle from
805
00:57:44.800 --> 00:57:48.079
the light took five hours twenty three minutes and the
806
00:57:48.199 --> 00:57:56.199
light two hours thirty seven minutes. Aristolochia gigas Aristolochias moves
807
00:57:56.280 --> 00:58:00.480
against the sun. July twenty second first circle was made
808
00:58:00.519 --> 00:58:04.519
in eight hour zero minutes, rather young shoot. July twenty
809
00:58:04.599 --> 00:58:08.280
second second circle was made in seven hours fifteen minutes.
810
00:58:08.880 --> 00:58:12.480
July twenty four to third circle five hours zero minutes.
811
00:58:12.679 --> 00:58:17.719
About In the foregoing table, which includes twining plants belonging
812
00:58:17.760 --> 00:58:20.840
to widely different orders, we see that the rate at
813
00:58:20.920 --> 00:58:24.119
which growth travels or circulates around the axis on which
814
00:58:24.239 --> 00:58:28.280
the revolving movement depends differs much as long as a
815
00:58:28.320 --> 00:58:31.840
plant remains under the same conditions. The rate is often
816
00:58:31.960 --> 00:58:37.119
remarkably uniform, as with the hop the Cania, phaseolas et cetera.
817
00:58:38.039 --> 00:58:41.760
The scapanthus made one revolution in one hour seventeen minutes,
818
00:58:42.119 --> 00:58:45.159
and this is the fistest rate observed by me. But
819
00:58:45.360 --> 00:58:50.039
we shall hereafter see a tendril bearing passiflora revolving more rapidly.
820
00:58:50.639 --> 00:58:54.280
A shoot of the Accidia quinata made a revolution in
821
00:58:54.400 --> 00:58:57.800
one hour thirty minutes and three revolutions at the average
822
00:58:57.880 --> 00:59:02.039
rate of one hour thirty eight minutes. A convolvolus made
823
00:59:02.159 --> 00:59:05.679
two revolutions at the average of one hour forty two minutes,
824
00:59:06.000 --> 00:59:09.960
and a Physiolus bulgaris three at the average of one
825
00:59:10.039 --> 00:59:13.719
hour fifty seven minutes. On the other hand, some plants
826
00:59:13.800 --> 00:59:16.559
take twenty four hours for a single revolution, and the
827
00:59:16.639 --> 00:59:21.559
ad hoda sometimes required forty eight hours. Yet this latter
828
00:59:21.679 --> 00:59:25.960
plant is unefficient. Twiner species of the same genus move
829
00:59:26.079 --> 00:59:29.280
at different rates. The rate does not seem governed by
830
00:59:29.440 --> 00:59:32.159
the thickness of the shootes. Those of the Sola are
831
00:59:32.239 --> 00:59:35.719
as thin and flexible as string, but move more slowly
832
00:59:36.079 --> 00:59:39.039
than the thick and fleshy roots of the ruscus, which
833
00:59:39.079 --> 00:59:43.280
seem little fitted for movement of any kind. The shoots
834
00:59:43.320 --> 00:59:46.639
of the Wistaria, which become woody, move faster than those
835
00:59:46.719 --> 00:59:52.079
of the hervaceous Ipomoea or thumburg air. We know that
836
00:59:52.280 --> 00:59:55.840
the internodes, whilst still very young, do not acquire their
837
00:59:55.960 --> 00:59:59.599
proper rate of movement. Hence these several shoots on the
838
00:59:59.639 --> 01:00:03.480
same plant may sometimes be seen revolving at different rates.
839
01:00:04.079 --> 01:00:07.079
The two or three or even more into nodes which
840
01:00:07.119 --> 01:00:11.000
are first formed above the cotylodon or above the rootstock
841
01:00:11.119 --> 01:00:15.079
of a perennial plant, do not move. They can support themselves,
842
01:00:15.159 --> 01:00:19.159
and nothing superfluous is granted. A greater number of twiners
843
01:00:19.239 --> 01:00:21.840
revolved in a course opposed to that of the sun
844
01:00:22.280 --> 01:00:24.039
or to the hands of a watch, than in the
845
01:00:24.159 --> 01:00:28.119
reversed course, and consequently the majority, as is well known,
846
01:00:28.440 --> 01:00:32.440
ascend for supports from left to right. Occasionally, though rarely,
847
01:00:32.800 --> 01:00:36.079
plants of the same order twine in opposite directions, of
848
01:00:36.199 --> 01:00:39.239
which more. Page one twenty five gives a case in
849
01:00:39.320 --> 01:00:42.840
the Leguminosae, and we have in the table another in
850
01:00:43.280 --> 01:00:47.760
a Canthasia. I have seen no instance of two species
851
01:00:47.880 --> 01:00:51.199
of the same genus t ining in opposite directions, and
852
01:00:51.360 --> 01:00:56.239
such cases must be rare. But Fitzmerla states that although
853
01:00:56.440 --> 01:01:00.599
Mecania scandens twins as I have described from left to write,
854
01:01:01.119 --> 01:01:05.280
another species in South Brazil twines in an opposite direction,
855
01:01:06.280 --> 01:01:09.760
it would have been an anomalous circumstance if no such
856
01:01:09.880 --> 01:01:13.599
cases had occurred for different individuals of the same species,
857
01:01:14.039 --> 01:01:19.360
namely of Solanum dol Camara de troche tone nineteen, page
858
01:01:19.440 --> 01:01:24.679
two ninety nine revolve and twine in two directions. This plant, however,
859
01:01:24.880 --> 01:01:30.119
is a most feeble twiner. Lasa Aurantacia leon page three
860
01:01:30.239 --> 01:01:34.360
fifty one offers a much more curious case. I raised
861
01:01:34.440 --> 01:01:38.440
seventeen plants. Of these eight revolved in opposition to the
862
01:01:38.559 --> 01:01:42.119
sun and ascended from left to right. Five followed the
863
01:01:42.239 --> 01:01:45.119
sun and ascended from right to left to end. Four
864
01:01:45.239 --> 01:01:48.679
revolved and twined first in one direction, and then reversed
865
01:01:48.719 --> 01:01:52.159
their course the petioles of the opposite leaves,
affording a
866
01:01:52.519 --> 01:01:56.880
pont d'apoe for the reversal of the spire. One of
867
01:01:56.960 --> 01:02:00.599
these four plants made seventh spiral turns from the right
868
01:02:00.760 --> 01:02:04.239
to left and five turns from left to right. Another
869
01:02:04.400 --> 01:02:08.960
plant in the same family, the scipanthus Elegance, habitually twines
870
01:02:09.079 --> 01:02:12.159
in this same manner. I raised many plants of it,
871
01:02:12.320 --> 01:02:15.719
and the stems of all took one turn or occasionally
872
01:02:15.800 --> 01:02:19.000
two or even three turns in one direction, and then,
873
01:02:19.119 --> 01:02:22.880
ascending for a short space straight reversed their course and
874
01:02:23.000 --> 01:02:26.519
took one or two turns in an opposite direction. The
875
01:02:26.639 --> 01:02:30.199
reversal of the carpature occurred at any point in the stem,
876
01:02:30.639 --> 01:02:33.920
even in the middle of an internode. Had I not
877
01:02:34.119 --> 01:02:37.960
seen this case, I should have thought its occurrence most improbable.
878
01:02:38.599 --> 01:02:42.320
It would be hardly possible with any plant which ascended
879
01:02:42.360 --> 01:02:44.920
above a few feet in height, or which lived in
880
01:02:44.960 --> 01:02:48.559
a un exposed situation. The stem could be pulled away
881
01:02:48.800 --> 01:02:53.239
easily from its support with but little unwinding, nor could
882
01:02:53.320 --> 01:02:56.719
it have adhered at all had not the internodes soon
883
01:02:56.920 --> 01:03:01.559
become moderately rigid with leaf pope, as we shall soon see,
884
01:03:01.960 --> 01:03:06.800
Analogous cases frequently occur, but these present no difficulty, as
885
01:03:06.880 --> 01:03:11.719
the stem is secured by the clasping tsuoles. In the
886
01:03:11.840 --> 01:03:15.239
many other revolving and twining plants observed by me, I
887
01:03:15.480 --> 01:03:19.480
never but twice saw the movement reversed once and only
888
01:03:19.599 --> 01:03:23.920
for a short space in Apomoya jakunda, but frequently in
889
01:03:24.039 --> 01:03:28.679
Hibertia dentata. This plant at first perplexed me much, for
890
01:03:28.840 --> 01:03:32.920
I continually observed its long and flexible shoots, evidently well
891
01:03:32.960 --> 01:03:36.360
fitted for twining, making a whole or half or quarter
892
01:03:36.519 --> 01:03:41.159
circle in one direction and then in an opposite direction. Consequently,
893
01:03:41.480 --> 01:03:44.440
when I placed the shootes near thin or thick sticks
894
01:03:44.800 --> 01:03:49.320
or perpendicularly stretched string, they seemed as if constantly trying
895
01:03:49.360 --> 01:03:53.440
to ascend, but always fail. I then surrounded the plant
896
01:03:53.519 --> 01:03:57.000
with a mass of branched quids. The shoots ascended and
897
01:03:57.159 --> 01:04:00.679
passed through them, but several came out laterally, and their
898
01:04:00.760 --> 01:04:07.400
dependent extremities seldom turned upwards, as if usual with twining planets. Finally,
899
01:04:07.840 --> 01:04:11.159
I surrounded a second plant with many thin upright sticks
900
01:04:11.519 --> 01:04:14.440
and placed it near the first one with twigs. Now
901
01:04:14.559 --> 01:04:17.320
both had got what they liked, for they twined up
902
01:04:17.360 --> 01:04:21.840
the parallel sticks, sometimes winding round one and sometimes round several,
903
01:04:22.280 --> 01:04:25.679
and the shutes traveled laterally from one to the other pot.
904
01:04:26.360 --> 01:04:28.920
But as the plants grew older, some of the shutes
905
01:04:28.960 --> 01:04:34.400
twined regularly up thin upright sticks. Though the revolving movement
906
01:04:34.800 --> 01:04:37.400
was sometimes in one direction and sometimes in the other,
907
01:04:37.800 --> 01:04:41.559
the twining was invariably from left to right, so that
908
01:04:41.920 --> 01:04:45.480
the more potent or persistent movement of the revolution must
909
01:04:45.519 --> 01:04:48.199
have been in opposition to the course of the sun.
910
01:04:49.159 --> 01:04:51.840
It would appear that this hibertia is adapted both to
911
01:04:51.920 --> 01:04:55.960
ascend by twining and to ramble literally through the thick
912
01:04:56.079 --> 01:05:01.159
Australian squall. I have described the above t in some detail,
913
01:05:01.519 --> 01:05:04.079
because as far as I have seen, it is rare
914
01:05:04.199 --> 01:05:08.079
to find any special adaptations with twining plants, in which
915
01:05:08.119 --> 01:05:12.199
respect they differ much from the more highly organized ten bobearers.
916
01:05:12.920 --> 01:05:17.079
The Solanum documara, as we shall presently see, can twine
917
01:05:17.239 --> 01:05:21.119
only round stems, which are both thin and flexible. Most
918
01:05:21.199 --> 01:05:24.679
twining plants are adapted to ascend supports of moderate though
919
01:05:24.800 --> 01:05:28.800
of different thicknesses. Our English twiners, as far as I
920
01:05:28.960 --> 01:05:33.360
have seen, never twine round trees, excepting the honeysuckle the
921
01:05:33.599 --> 01:05:37.440
Lonicera periclimenum, which I have observed twining up a young
922
01:05:37.559 --> 01:05:40.880
beech tree nearly four and one half inches in diameter.
923
01:05:41.960 --> 01:05:46.079
More page one thirty four found that Phaseolus multifloras and
924
01:05:46.280 --> 01:05:50.159
Epomoea herporea could not, when placed in a room with
925
01:05:50.239 --> 01:05:53.800
the light entering on one side, twine round sticks between
926
01:05:53.840 --> 01:05:57.480
three and four inches in diameter. For this interfered in
927
01:05:57.559 --> 01:06:01.960
a manner presently to be explained with the movement in
928
01:06:02.079 --> 01:06:05.760
the open air. However, the Phasiolus climbed around a support
929
01:06:05.880 --> 01:06:08.920
of the above thickness, but failed in twining round one
930
01:06:09.199 --> 01:06:13.840
nine
inches in diameter. Nevertheless, some twiners of the warmer
931
01:06:13.960 --> 01:06:17.880
temperate regions can manage this latter degree of thickness. For
932
01:06:18.039 --> 01:06:21.280
I hear from doctor Hooker that at Q the Ruscus
933
01:06:21.360 --> 01:06:26.199
androgenus has ascended a column nine inches in diameter. And
934
01:06:26.360 --> 01:06:29.000
although a wester Aia grown by me in a small
935
01:06:29.119 --> 01:06:32.000
pot tried in Vain for weeks to give round a
936
01:06:32.119 --> 01:06:35.519
post between five and six inches in diameter, yet at
937
01:06:35.639 --> 01:06:39.760
Q a plant ascended a trunk above six inches in diameter.
938
01:06:40.800 --> 01:06:44.519
The tropical twiners, on the other hand, can ascend thicker truths.
939
01:06:45.119 --> 01:06:48.199
I hear from doctors Thompson and Hooker that this is
940
01:06:48.400 --> 01:06:52.920
the case with the Rutea harviflora, one of the menace
941
01:06:53.079 --> 01:06:57.880
from Romeca, and with some Dalbergius and other luguminose. This
942
01:06:58.079 --> 01:07:01.199
power would be necessary for any species which had to
943
01:07:01.280 --> 01:07:04.639
ascend by twining the large trees of the a tropical forests,
944
01:07:05.119 --> 01:07:07.920
otherwise they would hardly ever be able to reach the light.
945
01:07:08.639 --> 01:07:11.480
In our temperate countries. It would be interious to the
946
01:07:11.559 --> 01:07:14.719
twining plants which die down every year if they are
947
01:07:14.880 --> 01:07:18.320
enabled to twine round trunks of trees, for they could
948
01:07:18.400 --> 01:07:21.280
not grow tall enough in a single season to reach
949
01:07:21.360 --> 01:07:25.360
the summit and gain the light. By what means, certain
950
01:07:25.440 --> 01:07:29.480
twining plants are adapted to ascend only thick stems, whilst
951
01:07:29.599 --> 01:07:32.559
others can twine round thicker ones, I do not know.
952
01:07:33.400 --> 01:07:36.360
It appeared to be probable that twining plants with very
953
01:07:36.440 --> 01:07:41.480
long revolving shoots would be able to ascend thicker support. Accordingly,
954
01:07:41.639 --> 01:07:46.960
I placed Serapegia gardinerie near a post six inches in diameter,
955
01:07:47.519 --> 01:07:50.559
but the shoots entirely failed to wind round it. Their
956
01:07:50.599 --> 01:07:53.599
great length and power of movement merely aid them in
957
01:07:53.679 --> 01:07:58.840
finding a distant stem round which to twine. Sperostema marmoratum
958
01:07:59.440 --> 01:08:02.400
is a big tropical twina, and it is a very
959
01:08:02.480 --> 01:08:06.199
slow revolver. I thought that this latter circumstance might help
960
01:08:06.239 --> 01:08:09.559
it in ascending a thick support. But though it was
961
01:08:09.679 --> 01:08:12.559
able to wind round a six in post, it could
962
01:08:12.599 --> 01:08:15.280
do this only on the same level or plane, and
963
01:08:15.440 --> 01:08:19.479
did not form a spire. And thus, as sand as
964
01:08:19.600 --> 01:08:23.680
ferns differ so much in structure from the fenerogamic plants,
965
01:08:24.079 --> 01:08:27.000
it may be worthwhile here to show that twining ferns
966
01:08:27.079 --> 01:08:30.159
do not differ in their habits from other twining plants.
967
01:08:30.960 --> 01:08:35.600
In Lagodium articulatum, the two internodes of the stem properly
968
01:08:35.680 --> 01:08:39.640
tod barachies, which are first formed above the rootstock, do
969
01:08:39.800 --> 01:08:43.520
not move. The third from the ground revolves, but at
970
01:08:43.640 --> 01:08:49.000
first very slowly. This species is a slow revolver, but L.
971
01:08:49.119 --> 01:08:53.520
Scandons made five revolutions each at the average rate of
972
01:08:53.640 --> 01:08:57.359
five hours forty five minutes, and this represents fairly well
973
01:08:57.520 --> 01:09:03.119
the usual brate taken quick and slow movers amongst phenerorganic plants.
974
01:09:04.000 --> 01:09:08.239
The rate was accelerated by increasing temperature at each stage
975
01:09:08.239 --> 01:09:12.359
of growth. Only the two upper internodes revolve. A line
976
01:09:12.479 --> 01:09:16.239
painted along the convex surface of a revolving internode becomes
977
01:09:16.319 --> 01:09:21.000
first lateral, then concave, then laterally and ultimately again convex.
978
01:09:21.640 --> 01:09:25.079
Neither the internodes nor the petioles are irritable When rummed.
979
01:09:26.079 --> 01:09:29.600
The movement is in the usual direction, namely in opposition
980
01:09:29.760 --> 01:09:32.119
to the course of the sun, and when the stem
981
01:09:32.199 --> 01:09:35.640
twinds around taking stick, it becomes twisted on its own
982
01:09:35.760 --> 01:09:39.520
axis in the same direction. After the young internetes have
983
01:09:39.680 --> 01:09:42.560
twined round the stick, their continued growth causes them to
984
01:09:42.720 --> 01:09:46.560
slip a little upwards. If the stick be soon removed,
985
01:09:46.680 --> 01:09:51.000
they straighten themselves and recommence revolving. The extremities of the
986
01:09:51.079 --> 01:09:55.600
depending shoots turn upwards and twine on themselves. In all
987
01:09:55.680 --> 01:09:59.720
these respects we have complete identity with twining fen organic
988
01:09:59.760 --> 01:10:03.039
play plants, and the above enumeration may serve as a
989
01:10:03.079 --> 01:10:07.760
summary of the leading characteristics of all twenty plants. The
990
01:10:07.920 --> 01:10:11.039
power of revolving depends on the general health and vigor
991
01:10:11.159 --> 01:10:14.479
of the plant, as has been lavoiously shown by palm,
992
01:10:15.479 --> 01:10:19.680
But the movement of each separate internode is so independent
993
01:10:19.840 --> 01:10:22.720
of the others that cutting off an upper one does
994
01:10:22.840 --> 01:10:26.720
not affect the revolutions of a lower one. When, however,
995
01:10:27.079 --> 01:10:30.239
the trochet
cut off two whole shoots of the heart
996
01:10:30.640 --> 01:10:34.119
and placed them in water, the movement was greatly retarded.
997
01:10:34.680 --> 01:10:37.279
For one revolved in twenty hours and the other in
998
01:10:37.399 --> 01:10:40.439
twenty three hours, whereas they ought to have revolved in
999
01:10:40.520 --> 01:10:44.079
between two hours and two hours thirty minutes. Shoots of
1000
01:10:44.199 --> 01:10:46.880
the kidney being cut off and placed in water were
1001
01:10:46.960 --> 01:10:50.760
similarly retarded, but in a less degree. I have repeatedly
1002
01:10:50.840 --> 01:10:53.760
observed the carrying a plant from the greenhouse to my room,
1003
01:10:54.159 --> 01:10:57.319
or from one part to another of the greenhouse, always
1004
01:10:57.359 --> 01:11:01.119
stopped the movement for a time. Hence I conclude that
1005
01:11:01.239 --> 01:11:03.239
the plant in a state of nature and growing in
1006
01:11:03.359 --> 01:11:07.319
exposed conditions, would not make their revolutions during stwami weather.
1007
01:11:08.239 --> 01:11:12.359
A decrease in temperature always caused a considerable retardation in
1008
01:11:12.439 --> 01:11:17.960
the rage of revolution. But Dutroche tomb seventeen, page nine
1009
01:11:18.119 --> 01:11:22.720
ninety four, nine ninety six has given such precise observations
1010
01:11:22.800 --> 01:11:25.520
on this head with respect to the common key, that
1011
01:11:25.680 --> 01:11:29.479
I need say no more. When twining plants are placed
1012
01:11:29.560 --> 01:11:31.560
near a window in a room, the light in some
1013
01:11:31.800 --> 01:11:35.359
cases has a remarkable power, as was LifeWise observed by
1014
01:11:35.520 --> 01:11:38.960
Utroche page nine ninety eight with the pa on the
1015
01:11:39.039 --> 01:11:43.359
revolving movement. But this differs in degree with different plants. Thus,
1016
01:11:43.479 --> 01:11:48.079
Ipomoya chacunda makes a complete circle in five hours thirty minutes,
1017
01:11:48.439 --> 01:11:51.439
the semicircle from the light taking four hours eighty minutes,
1018
01:11:51.520 --> 01:11:56.399
and that towards life only one hour. Lonitsera, Brakpota revolved
1019
01:11:56.560 --> 01:11:59.880
in a reverse direction to the Appomoya in eight hours,
1020
01:12:00.359 --> 01:12:03.720
the semicircle from the light taking five hours twenty three minutes,
1021
01:12:04.000 --> 01:12:06.600
and to the light only two hours thirty seven minutes.
1022
01:12:07.279 --> 01:12:10.079
From the rate of revolution in all the plants observed
1023
01:12:10.119 --> 01:12:12.880
by me being nearly the same during the night and
1024
01:12:13.119 --> 01:12:15.520
the day, I infer that the action of the light
1025
01:12:15.680 --> 01:12:19.079
is confined to retarding one semicircle and accelerating the other,
1026
01:12:19.520 --> 01:12:22.000
so as not to modify greatly the rate of the
1027
01:12:22.079 --> 01:12:26.399
whole revolution. This action of the light is remarkable where
1028
01:12:26.439 --> 01:12:29.319
we can reflect how little the leaves are developed on
1029
01:12:29.439 --> 01:12:33.239
the young and thin revolving internote. It is all the
1030
01:12:33.359 --> 01:12:38.399
more remarkable as botmisbelieve Mole page one nineteen, that to
1031
01:12:38.520 --> 01:12:41.680
twining plants are but little sensitive to the action of
1032
01:12:41.720 --> 01:12:45.960
the light. I will conclude my account of twining plants
1033
01:12:46.000 --> 01:12:50.000
by giving a few miscellaneous and curious cases. With most
1034
01:12:50.159 --> 01:12:53.920
twining plants, all the branches, however many there may be,
1035
01:12:54.439 --> 01:12:58.560
go on revolving together. But according to mole, page four.
1036
01:12:59.000 --> 01:13:03.720
Only the lateral branches of Tanus elephant types twine and
1037
01:13:03.880 --> 01:13:06.560
not with the stem. On the other hand, with a
1038
01:13:06.640 --> 01:13:10.880
climbing species of asparagus, the leading chute alone and not
1039
01:13:11.119 --> 01:13:14.000
the branches revolved and timed. But it should be stated
1040
01:13:14.039 --> 01:13:19.760
that the plant was not growing vigorously. My plants of Combrentum, Argentaum,
1041
01:13:20.159 --> 01:13:24.680
and sea purporium made numerous short, healthy shoots, but they
1042
01:13:24.720 --> 01:13:27.920
showed no signs of revolving, and I could not conceive
1043
01:13:28.039 --> 01:13:31.439
how these plants could be climates. But at last, see
1044
01:13:31.640 --> 01:13:34.640
Argentineum put forth from the lower part of one of
1045
01:13:34.720 --> 01:13:38.239
its main branches a thin shoot five or six feet
1046
01:13:38.319 --> 01:13:41.720
in length, differing greatly in appearance from the previous shoots,
1047
01:13:42.079 --> 01:13:44.960
owing to its leaves being a little developed. And this
1048
01:13:45.079 --> 01:13:49.760
shute revolved vigorously and twined, so that this plant produces
1049
01:13:49.960 --> 01:13:55.920
shoots of two kind. With Paraploca Gracier palm, page forty three,
1050
01:13:56.520 --> 01:14:02.560
the uppermost shoots alone twined Polygonum convolvolus twins only during
1051
01:14:02.760 --> 01:14:06.359
the middle of the summer palm, page forty three, ninety four,
1052
01:14:06.960 --> 01:14:10.560
and plants growing vigorously in the autumn show no inclination
1053
01:14:10.720 --> 01:14:16.039
to climb. The majority of the escalopadiasay are twiners, but
1054
01:14:16.159 --> 01:14:23.439
the Esclypeius nigra only in Pertilliori solo incipit scandera subvolubly
1055
01:14:23.640 --> 01:14:27.560
powles world are now quoted and confirmed by Palm page
1056
01:14:27.800 --> 01:14:34.800
forty one Asclepias vinceitoxicum does not regularly twine, but occasionally
1057
01:14:34.880 --> 01:14:39.279
does Palm page forty two, more page one twelve when
1058
01:14:39.359 --> 01:14:43.239
growing under certain conditions. So it is with two species
1059
01:14:43.319
--> 01:14:47.479
of Ceropaggia as I hear from Professor Harvey to these
1060
01:14:47.560 --> 01:14:51.079
plants in their native dry South African palm generally grow
1061
01:14:51.159 --> 01:14:54.520
erect from six inches to two feet in height. A
1062
01:14:54.720 --> 01:14:58.560
very few tallest specimens showing some inclination to curve, but
1063
01:14:58.680 --> 01:15:02.760
when cultivated near duble, they regularly twined up sticks five
1064
01:15:02.920 --> 01:15:08.079
or six feet in height. Most Convolvelasia are excellent twiners,
1065
01:15:08.520 --> 01:15:13.079
but in South Africa, Hypomeia argueroie almost always grow erect
1066
01:15:13.159 --> 01:15:16.359
and compact, from about twelve to eighteen inches in height,
1067
01:15:17.039 --> 01:15:21.039
one specimen alone in Professor Harvey's collection showing an evident
1068
01:15:21.119 --> 01:15:25.199
disposition to twine. On the other hand, seedlings raised near
1069
01:15:25.279 --> 01:15:29.520
Dublin twined upsticks above eight feet in height. These facts
1070
01:15:29.560 --> 01:15:32.359
are remarkable, for there can hardly be a doubt that
1071
01:15:32.520 --> 01:15:35.920
in the drier provinces of South Africa, these plants have
1072
01:15:36.039 --> 01:15:39.760
propagated themselves for thousands of generations in an erect condition,
1073
01:15:40.399 --> 01:15:43.239
and yet they have retained during this whole period the
1074
01:15:43.319 --> 01:15:48.039
innate power of spontaneously revolving and twining whenever their shoots
1075
01:15:48.079 --> 01:15:52.560
become elongated under proper conditions of life. Most of the
1076
01:15:52.640 --> 01:15:56.680
species of Phaseolus are twiners, but certain varieties of the
1077
01:15:56.760 --> 01:16:01.640
p Multiplorus produce leon page six eight one two kinds
1078
01:16:01.680 --> 01:16:05.319
of shoots, some upright and thick, and others thin and twining.
1079
01:16:05.680 --> 01:16:09.000
I have seen striking instances of this stroious case of
1080
01:16:09.119 --> 01:16:14.560
variability in Foma's dwarf forcing beam, which occasionally produced a
1081
01:16:14.680 --> 01:16:19.960
single long twining shoot. Solanum dolcamara is one of the
1082
01:16:20.000 --> 01:16:23.600
feeblest and poorest of twiners. It may often be seen
1083
01:16:23.800 --> 01:16:26.840
growing as an upright bush, and when growing in the
1084
01:16:26.960 --> 01:16:30.319
midst of a thicket, merely scrambles up between the branches
1085
01:16:30.359 --> 01:16:35.119
without twining. But when according to the Crochet Totome nineteen,
1086
01:16:35.359 --> 01:16:39.800
page ninety nine, it grows near a thin and flexible support,
1087
01:16:39.960 --> 01:16:42.960
such as the stem of a nettle. It twines round it.
1088
01:16:44.119 --> 01:16:47.920
I placed sticks around several plants and vertically stretched strings
1089
01:16:48.000 --> 01:16:52.119
close to others, and the strings alone were ascended by twining.
1090
01:16:52.760 --> 01:16:57.000
The stem twines indifferently to the right or left. Some
1091
01:16:57.239 --> 01:17:01.960
other species of Solanum and of another gene viz habrofeminos,
1092
01:17:02.479 --> 01:17:06.239
belonging to the same family, are described in horticultural works
1093
01:17:06.279 --> 01:17:09.439
as twining plants, but they seem to possess this faculty
1094
01:17:09.600 --> 01:17:12.920
to a very feeble degree. We may suspect that the
1095
01:17:12.960 --> 01:17:16.119
species of these two genera have as yet only partially
1096
01:17:16.199 --> 01:17:19.439
acquired the habit of climbing. On the other hand, with
1097
01:17:19.640 --> 01:17:23.720
Tacoma radicans, a member of a family abounded with twiners
1098
01:17:23.800 --> 01:17:27.079
and tendril bearers, but which climbs like the ivy by
1099
01:17:27.159 --> 01:17:30.439
the aid of rootlets, we may suspect that a former
1100
01:17:30.520 --> 01:17:33.680
habit of twining has been lost. For the stem exhibited
1101
01:17:33.760 --> 01:17:37.720
slight irregular movements which could hardly be accounted for by
1102
01:17:37.880 --> 01:17:41.119
changes in the action of the light. There is no
1103
01:17:41.279 --> 01:17:45.600
difficulty in understanding how a spirally twining plant could graduate
1104
01:17:45.760 --> 01:17:49.039
into a simple root climber. For the young internodes of
1105
01:17:49.119 --> 01:17:54.399
Begonia tridiana and of Hoya carnosa revolve and twine, but
1106
01:17:54.680 --> 01:17:58.560
likewise inmit rootlets which adhere to any hitting surface, so
1107
01:17:58.720 --> 01:18:01.760
that the loss of twining would be no great disadvantage,
1108
01:18:02.039 --> 01:18:05.119
and in some respects an advantage to this species, as
1109
01:18:05.199 --> 01:18:08.359
they would then ascend their supports in a more direct line.
1110
01:18:09.000 --> 01:18:10.520
End of Chapter one