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.” 1% 
Weismann 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 diff- 
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 
Roux: Der Kampf der Teile im Organismus. P. 39—44. 
