THE " INTELLIGENCE " OF PLANTS 83 



from place to place, know that they are condemned to starve or stifle 

 their offspring. Ev;ry seed that falls to the foot of the tree or plant is 

 either lost or doomed to sprout in wretchedness. Hence the immense 

 effort to throw off the yoke and conquer space. Hence the marvellous 

 systems of dissemination, of propulsion, and navigation of the air which 

 we find on every side in the forest and the plain ; amongst others, to 

 mention in passing only a few of the most strange, the aerial screw or 

 Samara of the Maple ; the bract of the Lime tree ; the flying machine 

 of the Thistle, the Dandelion and the Salsify ; the detonating springs of 

 the Spurge ; the extraordinary squirt of the Momordica ; the hooks of the 

 eriophilous plants ; and a thousand other unexpected and astounding 

 pieces of mechanism ; for there is not, so to speak, a single seed but has 

 invented for its sole use a complete method of escaping from the maternal 

 shade. 



There is, no doubt, a great deal of truth in Maeterlinck's view. 

 Necessity, i.e.., the elementary need of the plant, has been the 

 mother of its inventions, and such necessity has proved a most 

 auspicious opportunity for the inauguration of a method of 

 organic reciprocity which again has been the origin and the 

 mainstay of the greatest goods and blessings of life. Great as 

 are the mechanical achievements of the plant, so eloquently 

 acknowledged by Maeterlinck, greater far, and more important, 

 are those which may fitly be called its bio-economic achievements, 

 however accidental the causes that gave them birth. For it was 

 the latter kind cf achievement which equipped the plant for a 

 high position in life, far transcending in importance the conquest 

 of space, namely, the position of indispensable pioneer and main 

 supporter of organic civilisation. More particularly, if we 

 remember that the primitive bacteria already made use of the 

 method of Symbiosis, and that this rendered possible the appear- 

 ance of the higher plants, there seems to be every justification 

 for giving pride of place to the bio-economic rather than the purely 

 mechanical achievements of the plant, wonderful though these 

 be. Nay, we are justified in assuming that the organic and 

 psychical funds necessary for the engendering of some of these 

 inventions, have to a large extent been derived from biological 

 reciprocity. This undoubted symbiotic origin of many plant 

 capabilities must not be overlooked. It is a case of " inheritance 

 affording the means by which inheritance is improved," a state- 

 ment that I have culled from a review by Prof. J. Arthur 

 Thomson of a book on animal behaviour, by Dr. S. J. Holmes 

 (Nature, 24-5-17). 



We have seen that plants relatively backward in Symbiosis, 



