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The results of our observations concerning the motion of the leaf of the Sundew, when irritated are as follows

1. The leaves of Drosera possess a vitality which is clearly perceived by the motion of the different parts of the leaf.

2. Irritation is produced by the continued touch of all solid matter, as well as by X that of sulphur, saltpetre and muriatic [illeg] acid, thinned and put upon the leaf in single drops

3. Only to touch the leaf, or to shake the whole plant is not sufficient to produce any visible effect.

4. The power of accepting and diffusing irritation belongs equally to all parts of the leaf and gland appendages.

5. Every irritation is diffused centrifugally in every direction of the lamina

6. The motion of the irritable leaf is not done by means of joints in its different parts, but through a gradual curving of these parts.

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7. The gland appendages as well as the surface of the leaf, when irritated always move towards the irritating no object — or rather towards the spot where the irritation is caused.

8. The strength of the irritation and the rapidity of the motion of the different parts stand in a contrary proportion to their distance from the immediately irritated spot and depend on the bulk of the different parts of the leaf.

9. The movement of the leaf and of the glands surrounding its edge takes place also towards the underside of the leaf — ? No when irritation is produced on that part.

10. The irritated Drosera leaf does not turn again towards the Knospenlage. The way in which it curves is also produced by the same causes which produce its other upfoldings.

11. The manner, in which the surface of the leaf moves towards the irritating body depends on the nature, shape

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and position of the latter and on the nature of the leaf itself.

12. The joint like organs of sensitive plants are of importance only through a structure of cells, which being able to move the parts, fixes them and determines their direction.

13. The susceptibility to irritation of the Drosera leaf increases and decreases with the its activity in secretion; and therefore probably depends on the process of assimilation─

14. As long as the leaves are not undeveloped they not irritable and do not secrete

15. When the irritation is produced by means of solid matter its irritability is produced through determined by the size of the surface which has come in contact with the leaf.

16. The susceptibility for irritation depends only so far on temperature, as heat increases the activity of the developed leaf.

17. The motion of the irritated leaf takes place also under water.

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18. Conditions of light have no irritating influence on the leaf. Drosera shows 1 no movement of sleep.

19. The motion produced by irritation continues during the night.

20 The duration of the irritation depends on its strength and is never influenced by temperature.

21 The leaf which has become insensible through irritation — becomes again irritable after a secretion has taken place.

22 A weaker irritation does not interfere with the influence of a stronger one.

p 2. N. says cutting leaf does not cause movement

p 5 directive impulse

p. 8. Lamina of leaf first opens & then marginals & then submargin, so in reversed order to clasping.— ie marginal first close & first opened