60 SYMBIOGENESIS 



nutrition, we may assume that there existed thus in early 

 times a bio-economic (symbiotic) bond between cells and 

 animals based in the last analysis upon genuine biological 

 symbiosis ; much in the same way as we saw that there exists a 

 certain correlation between the nutritional activities of many 

 Copepods and those of neighbouring green algae. It is thus 

 again evident that normal and vital bio-economic relations 

 between plant and animal can and do quite well exist without 

 intimate attachment. Intimacy of attachment is no more the 

 criterion of the normality of relations than it is the criterion of 

 abnormal, i.e., parasitic relations, although in rank parasitism 

 attachments abound. 



The fact that the free-living alga frequently settles down 

 indolently in the mucilage which forms a slimy coating over 

 the body of C. roscoffensis constitutes, in my opinion, an 

 intimacy of the retrogressive order. The same interpretation 

 must be given to the fact that the egg-capsules apparently 

 exert a definite chemical attraction on the motile green cells. 



If here we have a case where " aus dem Keirn der 

 Bekanntschaft nach und nach holde Gewohnheit entspross," 

 this is rather in the direction of the parasitic relation. We 

 must remember that chemical attraction, like eating, "is a 

 mode of love," and that likewise, as has already been pointed 

 out, there is a vast domain of morbid attraction and of morbid 

 hunger. 



Well may it be that it is the egg-capsules themselves that 

 provide some of the green cells with an alluring medium for 

 growth without exertion. Some of the eggs which have died 

 eventually provide a still stronger temptation, a still richer soil 

 for indulgence and luxuriousness on the part of the alga. We 

 may assume that under the original symbiotic arrangement 

 both plant and animal throve well, and that both had enough 

 and plenty to spare. Instead of using their surplus, however, 

 to mutually progressive (symbiogenetic) purposes, temptation 

 led them into the path of indulgence. 



