72 Indications of a Central Zone of Development 



group of these centers, perhaps on account of some 

 special situation, to become, in the course or at the end of 

 the particular centroepigenesis producing the different 

 parts of the flower, and in relation to all the other centers 

 and so to the whole flower, the director to a further de- 

 velopment; so that there would be present for the whole 

 development of the flower, or for a part of it at least, a 

 centroepigenesis of the second degree. 



By analogy one can conceive also of the possibility of 

 other centroepigeneses of still higher degrees (composite 

 flowers, etc.). 



"It may appear," writes Le Dantec, "that the sexual 

 individual belongs to a higher order than the asexual in- 

 dividual and may originate from the individualization of 

 an association of parts which are like asexual individuals* 

 It occurs perhaps in the Medusae ; it is certain in Phane- 

 rogams. A flower corresponds morphologically to an 

 assemblage in a fixed form, of parts which are like the 

 asexual individuals of the plant. Goethe had already 

 noted this peculiarity. The asexual individual of a plant 

 is the internode with its leaf and auxiliary bud : flowers 

 are much more complex." 45 



Centroepigeneses of a second or higher grade could 

 thus serve to explain the transformation of simple colonies 

 of individuals, (e. g., of the ancestors of the present 

 echinoderms), into complicated organisms, which tend 

 steadily toward an individualization of their own. One 

 could explain easily the transformation, for example, of 

 the original individuals of the colony, becoming more and 

 more differentiated from one another, into the organs of 

 this organism (siphonophores). With the growth of 



"Le Dantec: Traite de Biologic. Paris, Alcan, 1903, P. 413. 



