286 SYMBIOSIS 



offspring to be preyed upon and decimated by their " domesti- 

 cated " allies. The disease has also been described under the 

 name of " Symphily." 



Another vicious circle produced by similar indulgence is 

 presented by the following example : the highly predaceous 

 Aphides, preying upon our pampered garden productions, excrete 

 a sweet substance upon the leaves of the plants, which substance 

 is very acceptable to certain fungi, enabling them to multiply 

 inordinately and thus to become a further pest upon these plants. 

 One parasite thus frequently abets another, the inverse order 

 of utility being in fact presented to what biological use and 

 biological relation should be. Although there be thus a 

 utilisation of metabolic surpluses, there is often nothing to show 

 that they .serve some really "highly useful purpose." On the 

 contrary, they serve a bad purpose, and it is fatal not to make the 

 respective distinctions. It is equally important to recognise 

 that the disease began with a setting aside of the conditions of 

 moderation as required by Symbiosis. 



The same criticism applies to Darwin's further remarks 

 with regard to the profusion of seeds amongst orchids. He fully 

 admits that such profusion is not anything to boast of : 



for the production of an almost infinite number of seeds or eggs is 

 undoubtedly a sign of lowness of organisation. That a plant, not being an 

 annual, should escape extinction, chiefly by the production of a vast 

 number of seeds or seedlings, shows a poverty of contrivance, or a want 

 of some fitting protection against other dangers. 



The orchids, then, we must assume, rank both high and 

 low ; the former in view of their wonderful cross-fertilising 

 contrivances, and the latter because of their redundant multi- 

 plications. Which is it to be : high or low rank ? The discrepancy 

 disappears if we judge both multiplication and cross-fertilisation 

 by bio-economic standards. 



Darwin had already mentioned (p. 225) that with regard to the 

 orchids we are in complete ignorance of the requirements and 

 conditions of life, and in his concluding remarks he similarly 

 states : 



What checks the unlimited multiplication of the Orchideae throughout 

 the world is not known. The frequency with which throughout the world 

 members of various Orchideous tribes fail to have their flowers fertilised, 

 though these are excellently constructed for cross-fertilisation, is a 

 remarkable fact. 



When we read of a capsule of a Maxillaria containing 1,756,440 



