Growth Integration 111 



instance, that in pieces of a flat-worm isolated by cutting 

 "the rate of metabolism is higher in long anterior pieces 

 than in posterior pieces of tlie same length.'' ^'^ 



Starting from this low but seemingly universal level of 

 integrative phenomena in tlie individual, Child foniuilates 

 views of the nature of organisms that agree verv well with 

 the organismal standpoint upheld in this volume. lie 

 writes: "Tlie organic individual apj)ears to be a unitv of 

 some sort. Its individuality consists primarily in tliis unity, 

 and the process of individuation is the progress of integra- 

 tion of a mere aggregation into such a unity, for this unity 

 is not simply the unity of a chance aggregation, but one of 

 a very particular kind and highly constant character for 

 each kind of individual. In all except the simplest individ- 

 uals it determines a remarkable degree of uniformity and 

 consistency, both in the special relations of parts and the 

 order of their appearance in time, and also in coordination 

 or harmony of functional relation to these parts after their 

 development." ^^ 



Meristic Gradients and Metabolic Gradients Both 

 Phenomena of Groieth Integration 



In view, then, of the exceedingly wide ])revalence in living 

 nature of axially disposed meristic series quantitivcly 

 graded, and of the equally wide or even wider })revalence of 

 axial gradients on the basis of metabolic activity, the 

 gradients of both sorts arising as- fundamental growtli plie- 

 nomena, it appears im])ossible to avoid recognizing our first 

 category of integration, namely, groxcth integration, as 

 a})out the most simple and ])rimal and universal of all these 

 categories, at least for nudticellular organisms. It seems 

 as though the other kinds of differentiation and integration 

 are superposed, as one might express it, upon this primordial 

 kind. To a consideration of the other, su])erimpos('d inte- 



