CHAPTER X A . 



THE INTEGRATION OF THE ORGANIC WORLD. 



314a. THAT from the beginning of life there has been 

 an ever-increasing heterogeneity in the Earth's Flora and 

 Fauna, is a truth recognized by all biologists who accept the 

 doctrine of evolution. In discussing the origin of species 

 Mr. Darwin and others have been mainly occupied in ex- 

 plaining the genesis of now this and now that form of 

 organism, considered as a member of one or other series, and 

 regarded as becoming differentiated from its allies. But by 

 implication, if not avowedly, there has been simultaneously 

 accepted the belief that the forms continually produced by 

 divergences and re-divergences, have constituted an assem- 

 blage increasingly multiform in its included kinds. And 

 this, which we are shown by the process of organic evolution 

 as followed out in its details, is a corollary from the doctrine 

 of evolution at large, as was pointed out in 159 of First 

 Principles. 



Meanwhile there has been little if any recognition of an 

 accompanying change, no less fundamental. In the general 

 transformation which constitutes Evolution, differentiation 

 and integration advance hand in hand; so that along with 

 the production of unlike parts there progresses the union of 

 these unlike parts into a whole. Examples of various kinds 

 before given will recur to the reader, and an addition to them 

 has just been set forth in the chapter on " Physiological 

 Integration." One more example, world-wide in its reach, 

 has still to be named. 



