THE LAW OF CONCORD IN NATURE 25 



see in more detail hereafter. What is obvious in Fertilisation, 

 namely, that there is co-operation and reciprocal differentiation 

 between the partners, i.e., male and female, is, of course, less 

 apparent in Nutrition ; but the indisputable and indispensable 

 connection between Nutrition and Symbiosis nevertheless shows 

 that we must look for a similar nexus in that case. 



It should be remembered that, as we now find in so many 

 instances, food exerts a controlling or directive influence upon 

 the development of the organism as well as its growth ; and 

 modern discoveries of the effects of vitamines are constantly 

 emphasising this fact. 



It is almost absurd to expect otherwise than that in a system 

 so profoundly correlated and co-evolved in its parts as that of 

 organic civilisation, the provision of important stimuli, such as 

 food is capable ol conveying, is achieved by very definite 

 arrangements, involving definite biological " duties " on the part 

 of the recipients as well as the providers of the food. 



It is also reasonable to expect that the effectiveness of food 

 will be found to depend upon the measure of biological co-opera- 

 tion that went towards its elaboration, and this is what I hope 

 to show. 



It has recently been found that ordinary organic substances 

 vary considerably in their behaviour according to their origin, 

 whence it is not a far cry to the recognition that food substances 

 vary in effectiveness in accordance with the nexus under which 

 they have been produced. A symbiotic nexus, for instance, gives 

 rise to such vitally useful substances as the vitamines. A 

 non-reciprocal (or perverted symbiotic) nexus, on the other hand, 

 results in the formation of such substances as the alkaloid poisons, 

 which are so appallingly injurious to the would-be aggressor, 

 or anti-reciprocal factor in the nexus. 



According to the investigations of Prof. E. J. Reichart, of 

 Pennsylvania, it would appear that over and above species 

 variation, differences due to environment and nurture are clearly 

 manifest in the starches, for instance. In other words, substances 

 vary in accordance with the treatment meted out to the producers 

 of the substances. 



In the previous chapter it was already demonstrated from the 

 case of the lichen that the organism which is equipped for 

 Symbiosis is thereby enabled to form powerful and widely useful 

 ferments, and that every increment of Symbiosis must mean 



