Thryallis brachystachys (Malpighiaceae) moves against the sun: one shoot made a circle in 12 hrs., and another in 10 hrs. 30 m.; but the next day, which was much colder, the first shoot took 10 hrs. to perform only a semicircle.

Hibbertia dentata (Dilleniaceae), placed in the hothouse, followed the sun, and made (May 18th) a circle in 7 hrs. 20 m.; on the 19th, reversed its course, and moved against the sun, and made a circle in 7 hrs.; on the 20th, moved against the sun one-third of a circle, and then stood still; on the 26th, followed the sun for two-thirds of a circle, and then returned to its starting-point, taking for this double course 11 hrs. 46 m.

Sollya Drummondii (Pittosporaceae) moves against the sun kept in greenhouse.

                                  H.  M.
April 4, 1st circle was made in   4   25
      5, 2nd                      8    0 (very cold day)
      6, 3rd                      6   25
      7, 4th                      7    5

Polygonum dumetorum (Polygonaceae). This case is taken from Dutrochet (p. 299), as I observed, no allied plant: follows the sun. Three shoots, cut off a plant, and placed in water made circles in 3 hrs. 10 m., 5 hrs. 20 m., and 7 hrs. 15 m.

Wistaria Chinensis (Leguminosae), in greenhouse, moves against the sun.

                                  H.  M.
May 13, 1st circle was made in     3   5
    13, 2nd                        3  20
    16, 3rd                        2   5
    24, 4th                        3  21
    25, 5th                        2  37
    25, 6th                        2  35

Phaseolus vulgaris (Leguminosae), in greenhouse, moves against the sun.

                                   H.  M.
May, 1st circle was made in         2   0
     2nd                            1  55
     3rd                            1  55

Dipladenia urophylla (Apocynaceae) moves against the sun.

                                   H.   M.
April 18, 1st circle was made in    8    0
      19, 2nd                       9   15
      30, 3rd                       9   40

Dipladenia crassinoda moves against the sun.

                                    H.  M.
May  16, 1st circle was made in      9   5
July 20, 2nd                         8   0
     21, 3rd                         8   5

Ceropegia Gardnerii (Asclepiadaceae) moves against the sun.

                                                         H.  M.
Shoot very young, 2 inches }
      in length            } 1st circle was performed in 7   55
Shoot still young            2nd                         7    0
Long shoot                   3rd                         6   33
Long shoot                   4th                         5   15
Long shoot                   5th                         6   45

Stephanotis floribunda (Asclepiadaceae) moves against the sun and made a circle in 6 hrs. 40 m., a second circle in about 9 hrs.

Hoya carnosa (Asclepiadaceae) made several circles in from 16 hrs. to 22 hrs. or 24 hrs.

Ipomaea purpurea (Convolvulaceae) moves against the sun. Plant placed in room with lateral light.

                                    {Semicircle, from the light in
1st circle was made in 2 hrs. 42 m. { 1 hr. 14 m., to the light
                                    { 1 hr. 28 m.:  difference 14 m.

                                    {Semicircle, from the light in
2nd circle was made in 2 hrs. 47 m. { 1 hr. 17 m., to the light 1 hr.
                                    { 30 m.:  difference 13 m.

Ipomaea jucunda (Convolvulaceae) moves against the sun, placed in my study, with windows facing the north-east. Weather hot.

                                    {Semicircle, from the light in
1st circle was made in 5 hrs. 30 m. { 4 hrs. 30 m., to the light 1
hr.
                                    { 0 m.:  difference 3 hrs. 30 m.

2nd circle was made in 5 hrs.       {Semicircle, from the light in
  20 m.  (Late in afternoon:         { 3 hrs. 50 m., to the light 1
hr.
  circle completed at 6 hrs. 40 m.  { 30 m.:  difference 2 hrs. 20 m.
  P.M.)

The Movements and Habits of Climbing Plants Page 11

Charles Darwin

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Charles Darwin

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