EXPERIMENTAL MORPHOGENESIS 



131 



of regeneration proper, until T. H. Morgan succeeded in 

 showing that in the genus Stentor it follows just the very 

 lines which we know already from our study of embryonic 

 organs or from Tubularia ; that an harmonious-equipotential 

 system is at the basis of what goes on. Now, you know 



a. 



cot 

 G o o G 



C u G G 

 GO O O 

 c o o G 



FIG. 13. CLAVELLINA. 



. Diagram of the normal animal: E and J openings; A' branchial apparatus; D= 



intestine; Af=stomach; //=heart. 

 b. The isolated branchial apparatus. 



c-e. Different stages of reduction of the branchial apparatus. 

 /. The new whole little ascidian. 



that all Protozoa are but one highly organised cell : we 

 have therefore here an instance where the so-called 

 " elements " of our harmonious-morphogenetic system are 

 not cells, but something inside of cells ; and this feature 

 must appear to be of very great moment, for it first show's, 

 as we have already pointed out on another occasion, that 

 morphogenesis is not dependent on cell-division, and it 

 states at the same time that our concept of the harmonious- 



