acted on within this time by geotropism;* nor had its own weight caused it to bend downwards.

On the following morning (19th) the glass filament was detached and refixed close behind the bud, as it appeared possible that the circumnutation of the terminal bud and of the adjoining part of the stolon might be different.  The movement was now traced during two consecutive days (Fig. 86).  During the first day the filament travelled in the course of 14 h. 30 m. five times up and four times down, besides some lateral movement.  On the 20th the course was even more complicated, and can hardly be followed in the figure; but the filament moved in 16 h. at least five times up and five times down, with very little

* Dr. A. B. Frank states (’Die Naturliche wagerechte Richtung von Pflanzentheilen,’ 1870, p. 20) that the stolons of this plant are acted on by geotropism, but only after a considerable interval of time. [page 216]

lateral deflection.  The first and last dots made on this second day, viz., at 7 A.M. and 11 P.M., were close together, showing that the stolon had not fallen or risen.  Nevertheless, by comparing its position on the morning of the 19th and 21st, it is obvious that the stolon had sunk; and this may be attributed to slow bending down either from its own weight or from geotropism.

Fig. 86.  Fragaria:  circumnutation of the same stolon as in the last figure, observed in the same manner, and traced from 8 A.M.  May 19th to 8 A.M. 21st.

During a part of the 20th an orthogonal tracing was made by applying a cube of wood to the vertical glass and bringing the apex of the stolon at successive periods into a line with one edge; a dot being made each time on the glass.  This tracing therefore represented very nearly the actual amount of movement of the apex; and in the course of 9 h. the distance of the extreme dots from one another was .45 inch.  By the same method it was ascertained that the apex moved between 7 A.M. on the 20th and 8 A.M. on the 21st a distance of .82 inch.

A younger and shorter stolon was supported so that it projected at about 45o above the horizon, and its movement was traced by the same orthogonal method.  On the first day the apex soon rose above the field of vision.  By the next morning it had sunk, and the course pursued was now traced during 14 h. 30 m. (Fig. 87).  The amount of movement was almost the same, [page 217] from side to side as up and down; and differed in this respect remarkably from the movement in the previous cases.  During the latter part of the day, viz., between 3 and 10.30 P.M., the

Fig. 87.  Fragaria:  circumnutation of another and younger stolon, traced from 8 A.M. to 10.30 P.M.  Figure reduced to one-half of original scale.

actual distance travelled by the apex amounted to 1.15 inch; and in the course of the whole day to at least 2.67 inches.  This is an amount of movement almost comparable with that of some climbing plants.  The same stolon was observed on the following day, and now it moved in a somewhat less complex manner, in a plane not far from vertical.  The extreme amount of actual movement was 1.55 inch in one direction, and .6 inch in another direction at right angles.  During neither of these days did the stolon bend downwards through geotropism or its own weight.