Coordinated Variations 211 



contemporaneous formation of thousands and millions 

 of new characters each adapted to the others and all 

 combined to perform some function such as must be 

 necessary in the phylogenetic passage from an aquatic 

 to a terrestrial life. And he concludes in these words: 

 "One must necessarily conclude that functional adaptation, 

 such as is produced in alteration of the conditions of 

 life, can bring about purposeful co-ordinations simulta- 

 neously in all organs of the body concerned. And the 

 characteristic feature of this simultaneity of action in 

 millions of parts must be the fact that it is opposed to 

 the action of natural selection which can never develop 

 simultaneously more than a very limited number of 

 purposeful characters." 16 



\Yeismann on whom the force of this objection aris- 

 ing from correlative development is not lost, has sought 

 to get around the difficulty by setting over against it, 

 as we have noted above, the neuter forms in bees, ants, 

 and termites. He does not deny the extraordinary diffi- 

 culty of explaining co-ordinated variations by natural 

 selection, but expects to show that in spite of it there 

 exist undoubted examples in which this difficulty was 

 overcome by natural selection. 



As to the polemic which raged between Weismann 

 and Spencer on the subject of these neuters, we have 

 already seen how in our view Spencer has succeeded in 

 driving his opponent from any tenable ground by 

 demonstrating convincingly that the neuters are really 

 nothing else than incompletely developed females. We 

 shall not return here to what has already been said. 



But it is worth while to observe that Weismann thus 



160 Roux: Der Kampf der Teile im Organismus. P. 39 44. 



