PLANT CONSCIOUSNESS 



447 



acting by moans of a nerve on the gastric glands, We may therefore 

 concede that it is the action of the same power in the plant that produces 

 the same effect. The motor is absent, but the motion is there. Further, 

 in this connection the idea becomes stronger from the fact that if grains 

 of sand be placed on the leaf the glands do not give out the digestive 

 fluid. 



The Hedysarum of Bengal is an example of movement without external 

 cause. This plant gyrates the central leaflet of its pinnule. Its lateral 

 leaflets are, however, the most remarkable, for they have the strange power 

 of jerking up and down. This motion will sometimes stop of its own 

 accord, and then suddenly, without any apparent cause, commence afresh. 

 The leaves cannot be set in motion by a touch, though exposure to cold 

 will stop the movement. If the movement be temporarily stopped by the 

 leaf being held, it will immediately resume action after the restraint is 

 removed, and, as if to make up for lost time, will jerk up and down with 

 increased rapidity. 



The power of spontaneous movement is also seen in the seed-spores 

 of seaweeds and other lowly plants. These spores move about in water 

 with freedom, and the filaments of many of the Liverworts exhibit a 

 capacity for extraordinary motion. In the spores of the Potato fungus, 

 Phytophtliora infcstans, we have a well-marked instance of the power of 

 movement according to circumstances. When the spore-cases burst, a 

 multitude of little bodies escape, and if these gain access to water — a drop 

 of dew on the Potato leaf for instance — they develop a couple of curious 

 little tails by means of which they swim about after the manner of 

 tadpoles. The power of locomotion possessed by the antherozoa of 

 Mosses, Ferns, &c, is again another example of this power of movement. 

 Tt is not so very long ago since these were classed as animalcuhe, and in 

 those days it was not disputed that these so-called little animals moved 

 consciously and intelligently. Then there are those microscopically 

 beautiful unicellular plants, the Desmids and Diatoms, which dart about 

 hither and thither in water. A mere cursory observation of their move- 

 ments leads one to believe them possessed of consciousness. 



It is not only in the fully developed vegetable organism that we find 

 evidence of the existence of brain-power, but this power begins to display 

 itself with the germination of the seed. In the commencement of plant-life 

 we find, as in the case of grain (to give an easily tested example), that the 

 root or radicle emerges at one end of the seed, and the shoot or plumule 

 at the other. What causes the former to descend and the latter to ascend ? 

 If the seed be so placed that the root comes out at the top, the result is the 

 same, for the root at once turns round and grows downward, and the 

 shoot vice versa. This cannot be caused by gravitation, although Darwin 

 once thought so, as the force of gravity would have the same effect on the 

 shoot as on the root. There can only be one answer, that is, the existence 

 of a directing force or brain-power. There is no structure in plants more 

 wonderful in its action than the tip of the root. Darwin wrote : " It is 

 hardly an exaggeration to say that the tip of the radicle, endowed as it is 

 with such diverse kinds of sensitiveness, acts like the brain of animals." 



A study of the habits of climbing plants affords further evidence of 

 the existence of nervous energy in them, of which perhaps the strongest 

 is the sensibility of tendrils. If a pencil or rod be rubbed on the inside of 



