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THE TWINING OF THE STEMS OF THE HEDGE BINDWEED, ETC.3 — 
Several plants of Calystegia sepium (hedge bindweed) were faithfully studied, for some weeks, by S. W. Beaumont. It is generally stated that the stems of this plant ascend by coiling met the sun, or from right to left, as viewed from the outside. On a stalk of nettle were observed two vines twining in opposite directions.
 
By tracing these two vines, they were found to preserve their opposite directions for their entire length. Another plant had 2 two branches starting near the root. Each of these branches, and every branch on these divisions throughout, preserved the same course. This was also found to be the case in a vine twining in an opposite direction. Experiments to induce vines to reverse their course proved of no avail. Straight stakes were placed in the ground for the vines to twine about. After arriving at the top, the vines fell or lopped over; some drooping slightly, some ascending. If the top of a plant is weak, the vine often leaves it before reaching the top. Sometimes the vine becomes 

3 Abstracts from papers of students of Michigan Agricultural College, made by Professor W. J. Beal,

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twisted, but not always. The vines are quite slender, and often reach off from their support to a great length. One branch reached four feet and six inches, nearly in a horizontal position; which reached out twenty inches, passed over a sixth of the circumference in three-quarters of an hour. Sometimes the vines can almost be seen to move. They appear to move most rapidly in the hottest part of the hottest days. 

Mr. T. F. Millspaugh experimented with wild cucumber (Echinocystis lobata). He trained a plant on a straight upright stake. 

The vine grew erect until it was about fifteen inches above the stake, and then bent over at about an angle of 45 degrees. It gradually dropped to a horizontal position and grew four feet and nine inches beyond the stake. Then it turned, and began to grow back on itself down to the stake. Here it neither went up nor down, as we should suppose, but grew right on the other side of the tip of the stake, till, at the time of writing, it had gone twenty inches. Before the vine doubled back on itself it described a complete circle in one hour and forty-five minutes. It went fastest on one hot day, between one and three o’clock. Tendrils were made to coil by irritation of various objects. He examined fifty specimens of tendrils which had made coils. It is well they turn in one direction for a part of their course, and then turn in the opposite direction. In one tendril there were seven of these changes in direction; in two there were six changes; in six there were five; in eleven there were four; in twenty-three there were three; in five there were two, and in two there was one change.