68 Geometrical relation of Nuclei 



coordinating and regulating influence with very diverse and 

 mysterious ways and means of application, not unlike the re- 

 capitulatory ; ' constraint" which twenty years ago was held to 

 cause organisms to develop along a certain ancestral course, and 

 is amenable with difficulty, if at all, to exact computation. 



While welcoming the conception because it involves the 

 postulation of some form of energy not present in inanimate 

 bodies, one may ask whether for the present it would not be more 

 profitable to go no further in the search for the unknown vitalistic 

 factor than the recognition and investigation of a special form of 

 energy not so wholly different from certain known forms of energy. 



Such a form of energy might be conceived of as acting from a 

 centre like gravitation, statical electricity or magnetism ; as causing 

 movements of attraction or repulsion according to the conditions 

 under which it is acting; as being a constant attribute of living 

 matter and exerting no influence on non-living material; and as 

 possessing the peculiarity of automatic and rhythmic alternation 

 between unipolar and bipolar states. 



May not Driesch's "Entelechy 511 prove to be the more complex 

 action of some such simpler form of energy in combination with 

 other forces ? 



May not Entelechy bear to this simpler form of energy some 

 such relation as that, for example, which the gyroscope bears to 

 gravity, and the real vital factor be something rather less complex 

 and also easier to investigate by exact methods of mensuration 

 and computation? 



In 1894 Roux made the disco verv that the blastomeres of cells 



/ 



of Rana fusca towards the end of segmentation, if isolated and 

 floated in a suitable medium, will show distinctly attractive pro- 

 perties inter se, so that the sides of each cell will become drawn 

 out towards a closely neighbouring cell, and such cells, eventually 

 moving towards each other and coming actually into contact 

 become pressed and flattened up against one another. This 

 phenomenon Roux termed cytotropism, which he has since 

 changed to cytotaxis, a term also adopted more recently by 

 Przibram. 



If this alleged attraction is a reality and if it is a universal 

 law, then the discovery of this fact must be regarded as one of 



