THE LIVING SUBSTANCE. 



115 



demonstrated in his physical foams, for these researches proved 

 nothing for me more conclusively than that the physical op- 

 portunities of its form are made large use of by the living 

 substance. But this is mere incident in its whole life history. 



[105] All the facts relating to the filose habit of the substance 

 are most interesting when taken in relation to the possibility 

 that Metazoa had their rise not from an ancestral amoeboid 

 stem but from an ancestral rhizome of Filosa. The new facts 

 seem to suggest that the Metazoa arose rather from a filose 

 type which by coalescence, or areal differentiation, built itself 

 up into compound masses. If by coalescence, the substance as 

 such showed respect to that position in the mass in which it 

 newly found itself, exactly as in each individual it had through 

 all its ceaseless flux respected its relative position; for it must 

 not be forgotten that in these protoplasts the substance as such 

 is ever changing its position in the mass or organism. 



By such hypothesis, complexity of organisms would arise 

 by extension and multiplication of areal differentiations which 

 were but rearrangements and redistributions of the two sets of 

 foam elements in relation to each other; in short by mere con- 

 tinuance and extension of exactly the same state of things that 

 existed in the individual as a starting point. 



This hypothesis would be a true description of the phe- 

 nomena which can be seen to take place in development of a 

 starfish, sea-urchin, rotifer, annelid, frog, or hen's ^g^. 



It is a very difficult thing to grasp this idea of a sensitiveness 

 of the substance as such to its position in the mass; it cer- 

 tainly would not occur to one a priori. The reader is reminded 

 of the viscosity rhythms of the substance in sea-urchin and 

 starfish as correlated with its position in the whole mass 

 whether this were of single cells or of many cells. In all pro- 

 toplasts the same thing is seen. In the phenomena of leuco- 

 cytes of crab's blood it seems that organization of this sort is 

 instinctive among even wandering cells of a Metazoan organism, 

 under even novel stimulus of opportunity or external conditions. 



A still clearer understanding of what is here meant can be 

 given by citation of an organism which, before the heart of 

 these researches was reached, was thought to be from the cell 



