BIONOMICS 191 



they represent a world of the utmost activity: "Das ist ein 

 Hiipfen, Tanzen, Springen, ein Zusammenprallen and 

 Voneinanderfliehen, dass man Miihe hat, sich in dem Gewirre 

 zurechtzufinden." ("There are hopping, dancing, leap- 

 ing, colliding and dispersing movements going on so that 

 one has great difficulty in seeing one's way in the confusion.") 

 All of which recalls biological phenomena, as does also the fact 

 that the variations in the surface-tension of a cell (and, hence, 

 in the output of work and, hence also, in evolution) depend on 

 the nature of its inorganic associations (concentration of salts 

 and minerals ingested at various positions in or near the 

 surface). 



A further analogy with (biological) symbiogenesis, or 

 biological " alchemy," as we have seen it to be operative in 

 cross-feeding and cross-fertilisation, is to be found in the 

 world of colloids in the fact that frequently a transformation 

 of crystalloid into colloid matter is achieved by a kind of 

 " infection," viz., by the action of acids " Anatzen," as the 

 Germans call it. Another method of transformation, a direct 

 imitation of the digestive "alchemy" of the human body, 

 consists in " Peptisation " viz., adding to a crystal certain 

 salts, the so-called Sol-formers. The term "Peptisation" is 

 indeed borrowed from the digestion of albumin in the stomach, 

 where, as is well known, small traces of hydrochloric acid are 

 capable of changing quantities of albumin into colloidal 

 solutions, thus rendering them fit for further elaboration by 

 the organism. 



An explanation of the principle underlying the peptisa- 

 tion of crystals has not yet been put forward. On the lines of 

 my symbiogenetic theory, however, and in view of the fact 

 that special activities (work !) are universally manifested in 

 the very act of change of state, I would suggest that in the 

 evolution of the inorganic as of that of the organic world, a 

 principle of reciprocal differentiation regulating all affinities 

 has gradually sprung up " holde Gewohnheit aus dem Keim 

 der Bekanntschaft " and that the resulting synthesis must 



