THE VEGETABLE KINGDOM. 475 



the Mimosa, having recovered from its fright, opened all 

 its leaves little by little, and kept them expanded so long 

 as the movement lasted. It had accustomed itself to 

 the motion. But as soon as the vehicle stopped, the same 

 peculiarity was repeated, and on starting the plant con- 

 tracted afresh, only to open again when farther off. ^ 



Many plants perform instinctively almost incredible 

 actions in seeking for the necessaries of their existence. 

 M. Grimard in his charming Avork on botany, written 

 with remarkable independence of thought, Cjuotes the his- 

 tory of a Scaly Lathrtea {LatJtrcea squamaria, Linn.), 

 which, having germinated at the bottom of a mine, raised 

 itself to the prodigious height of 120 feet in order to reach 

 the light, although it ordinarily attains a length of only 

 five or six inches. 



^ In the Proceedings of the Botanical Congress, at London, in 1866, there is 

 au exhaustive paper by Professor Caspary, on movements induced in different 

 trees by cold. It seems to be made out that tlie seat of such movements is the 

 protoplasm, not the outer cell-wall. The contractile power of the protoplasm is 

 strongly marked in the Selaginella mutahilis, which, when exposed to a bright 

 light, becomes of a pale whitish milky colour, but resumes its green tint when 

 the intensity of the light is diminished. The rhythmical tremors observed by 

 M. Lecocj in the leaves of Colocasia esculenta are so violent, that on one 

 occasion the pot in which the plant was growing was so shaken that it could 

 with difficulty be steadied. The Oxalis sensitiva, probably in its own countr}' 

 the most sensitive of plants, is in this country (England) nearly or quite 

 destitute of such a power. One of the most extraordinary of these plants 

 is the jDesrnodium gyrans, or telegraph plant, possibly the same plant de- 

 scribed by M. Pouchet as D. oscillans, a native of India. The leaves consist 

 of two small lateral leaflets and a terminal one. The latter works up and 

 down according to the intensity of the light, while tlie side leaflets work 

 day and night like the old semaphore signals. Dr. Masters confirms the state- 

 ment of Desfontaiues as to the effect of travelling on the Mimosa, having noticed 

 it while conveying a specimen by railw.ay. When the ether s|>ray is directed 

 with some force upon the leaves of the Mimosa pitdica they close up, but if the 

 spray be so directed that it only touches the leaves very gently, they seem para- 

 lyzed. Analogous facts are constantly seen in disease. M. Elondeau says that 

 when a direct current from a galvanic battery is passed through the plant it is 

 not affected, but if an indirect current from a small Ruhmkorff coil be substi- 

 tuted, the leaflets roll up immediately. — Popular Science Review, vol. vii. p. 22. — Tr. 



