THE LAW OF CONCORD IN NATURE 41 



This view of the matter seems to some extent corroborated 

 by recent experience of Plant-Teratology. Thus it is stated by 

 Mr W. C. Worsdell, F.L.S., in his work on the subject, that the 

 root of the vascular plant is less prone than any other organ to 

 deviate from the normal form, i.e., it is least predisposed to 

 teratological developments which are largely pathological. 



When we bear in mind that, as I have tried to show throughout, 

 the premier industry of the plant the industry which, because 

 of its symbiotic significance, is the best safeguard of healthy 

 development consists in the conversion of inorganic into 

 organic material, it seems doubly remarkable that those parts 

 which are most busily engaged upon such industry, though ever 

 so unobtrusively and even shut away from sun-light, are the most 

 robust in health and the most constant or " normal " in con- 

 stitution. Little doubt, that the connection with ideal food and 

 ideal work in this instance is a paramount factor in determining 

 the healthiness of the root. 



Mr. WoVsdell suggests that the comparative stability of the 

 root may be due to its usual 



Location in the comparatively uniform environment of the soil, where 

 the factors which induce variation are very much less numerous and varied 

 than they are above ground. 



I take it, however, that we have here above all to do with 

 capacity to resist disease, which capacity, as we have seen, cannot 

 be satisfactorily explained on purely mechanical grounds. The 

 soil may present a comparatively uniform " environment," but 

 surely this " environment " is not germ-proof. If the soil is 

 lacking in factors making for diversity, it also lacks certain factors 

 which usually make for health and normality such important 

 germicides, for instance, as fresh air and sunlight. The case of 

 the strenuous nitrifying soil bacteria versus the idle or predatory 

 soil organisms supplies strong confirmation of the view that 

 health and resistance everywhere primarily depend upon work 

 and Symbiosis v.ith the necessarily implied cross-feeding. 



If it may be said that the resistance to teratological develop- 

 ments on the part of the root is due to the comparatively uniform 

 factors presented by the soil, this view, in my opinion, needs to 

 be supplemented by the further statement that the factors are 

 constant because correlated with symbiotic strenuousness, which 

 ipso facto precludes relations with the animate environment 

 that make for morbidity. 



