342 SYMBIOGENESIS 



forms a new species, just as in a kaleidoscope, as soon as on turning 

 it one particle falls, the others also are disturbed and arrange themselves 

 in a new figure as it were recrystallise. 



We have just seen how this works out in pathogenesis, and 

 how inversely very gradual synthetic processes of correlated 

 growth and correlated inheritance mark evolution by symbio- 

 genesis. 



The abundance of the species which have been formed by degenera- 

 tion, by retrogression, is known to every zoologist. It is self-evident 

 that their origin is to be traced to the action of external conditions, 

 that they have been produced by acquired and inherited changes of 

 growth depending on these conditions. 



Thus again we see in the case of a zoologist as we saw 

 previously in the case of a botanist and of a pathologist, that, 

 in the absence of bio-economic explanations, the mere fact of 

 the abundance of abnormality becomes so bewildering that the 

 possibility of self-pauperisation is never broached, even by the 

 most philosophically inclined amongst them. 



Yet we are loath to admit the excuse of external condi- 

 tions in a human degenerate ! Though it is justly pleaded that 

 more frequently than not his is a case of heredity which 

 should indeed, if proved, be at least an extenuating circum- 

 stance yet his degeneracy is frequently connected with 

 previous transgressions within the particular stock, i.e., the 

 responsibility rests with a kind of specific self-pauperisation. 

 In the Biblical terms, " I will visit upon you the sins of your 

 fathers unto the third and fourth generation." These words, 

 according to Prof. Eimer, " have a profound significance, and 

 the manner of life, the lot in life, and the selection of the 

 ascendants in great measure determines the fate in the life of 

 coming generations." 



The importance of the distribution of blood in the body as 

 a physiological factor determining growth in a definite 

 direction, is also mentioned. We have seen how this distribu- 

 tion is determined by nutrition, i.e., by factors of biological 

 symbiosis which in their powerful reaction determine the 

 conditions of domestic symbiosis. 



