126 SCIENCE AND PHILOSOPHY OF THE ORGANISM 



Instances of " Harmonious- Equipotential Systems ' 



We must try at first to learn a few more positive facts 

 about our systems, in order that we may know how im- 

 portant is the part which they play in the whole animal 

 kingdom, and in order that our rather abstract analysis may 

 become a little more familiar to us. We know already that 

 many of the elementary morphogenetic organs have been really 

 proved to be harmonious-equipotential systems, and that the 

 same probably is true of many others ; we also know that 

 the immature egg of almost all animals belongs to this type, 

 even if a fixed determination of its parts may be established 

 just after maturation. Moreover, we said, when speaking 

 about some new discoveries on form-restitution, that there 

 are many cases in which the processes of restitution do not 

 proceed from single localities, the seat of complex potencies 

 in the organism, but in which each single part of the 

 truncated organism left by the operation has to perform 

 one single act of restoration, the full restitution being the 

 result of the totality of all. These cases must now be 

 submitted to a full analysis. 



All of you have seen common sea-anemones or sea-roses, 

 and many of you will also be familiar with the so-called 

 hydroid polyps. Tubularia is one genus of them : it looks 

 like a sea-anemone in miniature placed on the top of a stem 

 like a flower. It was known already to Allman that 

 Tubularia is able to restore its flower-like head when that 

 is lost, but this process was taken to be an ordinary re- 

 generation, until an American zoologist, Miss Bickford, 

 succeeded in showing that there was no regeneration process 

 at all, in the proper sense of the word, no budding of the 



