EXPERIMENTAL MORPHOGENESIS 135 



But, if we intentionally disregard this difficulty, in spite 

 of its fundamental character, how could the hypothesis of 

 chemical disintegration give the reason for the differentia- 

 tion of our harmonious-equipotential systems, with special 

 regard to the localisation of it ; how could it account, in 

 other words, for the appearance of typically localised speci- 

 fications in an organ for which no external localising causes 

 can be predicated ? 



Let us remember that a few original intimate differences 

 exist in our harmonious systems : the main directions of 

 the intimate protoplasmic structure including polarity and 

 bilaterality. There are therefore three times two specified 

 poles in each of these systems, at least in bilateral organisms, 

 but no other differences are present in them. A few very 

 simple cases of harmonious differentiation might indeed be 

 understood on the theory of a disintegrating chemical com- 

 pound in connection with these few differences. Imagine 

 that the original compound, of the quantity a, is disintegrated 

 to the amount of a^ ; from a^ are formed the two more 

 simple compounds, b and c, both of them in definite 

 quantities ; then we have the three chemical individuals, 

 a 1} b and c, as the constituents of our harmonious system ; 

 and it now might be assumed, without any serious difficulty, 

 though with the introduction of some new hypotheses, that 

 the two poles of one of the fundamental axes of symmetry 

 attract b and c respectively, a a x remaining unattracted 

 between them. We thus should have the three elementary 

 constituents of the system separated into three parts, and 

 as they all three are of a definite quantity, their separation 

 would mean that the system had been divided into three 

 parts, a a lt b and c, also with regard to its proper form. 



