MALADIE ET SYMBIOSE 237 



prejudicial feature of Parasitism, a view which would cause, as 

 the writer himself realises, almost all organisms to be classed as 

 parasites, seeing that they are in one way or another dependent 

 upon one another. True, the writer at least grants that green 

 plants, since they build up their food from the inorganic elements, 

 from the air and the soil, "are furthest removed from the suspicion 

 of dependence " ; but it seems scarcely ever to have dawned 

 upon that writer that we must clearly distinguish kinds and 

 degrees of " dependence." On a reasonable, bio-economic view 

 of the matter, dependence per se is not a fault at all ; but only 

 illegitimate, i.e., non-reciprocal dependence imparts the taint 

 of Parasitism. The article in the Encyclopedia shows clearly 

 that it is the absence of sociological criteria which has engendered 

 so much misconception and confusion of thought in Biology. 

 It is merely a " counsel of despair " when the writer continu s : 

 " The necessary additional conceptions are two : the bodies of 

 host and parasite must be in temporary or permanent physical 

 contact other than the mere preying of the latter on the former ; 

 and the presence of the parasite must not be beneficial, and is 

 usually detrimental to the host." 



Failing a sociological, we have here a physical conception, 

 which has the effect of quite unduly narrowing down the issue. 

 Whilst " contact " is over-emphasised, partnership is under- 

 estimated, and the rider with regard to the casual injuriousness of 

 parasites reads rather as an afterthought, as an accidental and 

 not as what it is, namely, the most important matter. Such 

 being the premises of " la biologic positive," we cannot wonder 

 at the comparative sterility of Prof. Bernard's conclusions 

 with regard to immunity and disease, which, so far from 

 providing the object lesson that Symbiosis and disease are 

 opposites, have carried him not much further than to surmise 

 that the two may well be " des phenomenes comparables " 



(P- 159). 



A paltry conjecture indeed ! 



Prof. Bernard is not, as might perhaps be imagined, putting 

 forward a theory akin to that of Symbiogenesis. He merely 

 contends that there occurs a gradually intensified series of mutual 

 adaptations between certain classes of orchids and fungi 

 precarious adaptations because liable to violent fluctuations in 

 point of mutual usefulness, of healthiness and permanence. 



After all that has been said in the preceding pages, it is 



