GENETICS 163 



"profits" in anti-social parasitic trades. In every case 

 "characters " would varj- with the trade; if the trade is anti- 

 social, new " factors " will constantly arise tending to render the 

 trader increasingly anti-social and anti-eugenic. In a similar 

 way we have seen that loss of symbiotics means loss of valuable 

 biological correspondences, and hence it may also mean the 

 advent of a plurality of new "factors."* If we understand 

 the importance of qualitative factors in biological analysis, 

 there is thus nothing miraculous in Mendelian phenomena, but 

 they must be considered as incidental upon the operations of 

 symbiogenesis and its obverse retrogenesis or degeneration 

 (Entartung !) 



It is not a coincidence that Vilmorin, Klebs and 

 Dr. Walker all use illustrations drawn from the sphere of 

 human economics "private property" of the organisms, 

 "good" and "bad" species they are compelled by the 

 actualities of each case to use such economic phraseology 

 though no such terms are provided as yet by orthodox biology. 



We cannot be surprised that our present methods of indis- 

 criminate breeding are ill calculated to produce constant races, 

 seeing that these methods are so little in accordance with 

 nature's gradual bio-economic methods. Prof. Klebs seems to 

 think that the prospects of producing new races by cultivation 

 appear to be full of promise, provided we give up much 

 prejudice regarding "favourable" nutrition (surfeit!), with 

 which I heartily agree. " So long as the view is held that good 

 nourishment, i.e., a plentiful supply of water and of salts, 

 constitutes the essential characteristic of garden-cultivation, 

 we can scarcely conceive that new mutations can be thus 

 produced ! " 



Evidently what is required is knowledge of the bio- 

 economic adequacy of nutrition. Failing this knowledge, 

 Prof. Klebs has to admit that the question as to the causes of 



* Prof. Bateson suggests that the wild crab-apple contains inhibiting elements 

 which the cultivated kinds have lost. I would simply say that the cultivated 

 apple has become somewhat surfeited at the expense of symbiotics, whilst the 

 crab has not. 



M 2 



