From the Unconscious to the Conscious 



doubt of this, since we see this evolution renew itself 

 in the life of the tadpole by a series of changes, perfecting 

 the heart, causing lungs to appear, and developing legs. 

 But rudiments of legs and lungs would give no 

 advantage to a fish which might possess them. In order 

 to have an advantage over its congeners, it is indispen- 

 sable that its heart, lungs, and organs of locomotion 

 should be already sufficiently developed to allow it to 

 live out of the water; as the tadpole does, once its evolu- 

 tion is complete, but not till then. 



The embryonic transformations of insects are more 

 striking still. There is such an abyss between the 

 anatomy and the physiology of the larva and that of the 

 perfect insect, that it is evidently impossible to find in 

 natural selection the explanation of its ancestral evolu- 

 tion. 1 



Alive to the validity of this objection, certain neo- 

 Darwinians have not hesitated to call in the Lamarckian 

 theory of the influence of the environment and to refer 

 such modifications as are creative of new species to the 

 joint influence of adaptation and selection. 



This theory, known as organic selection, has been 

 formulated by Baldwin and Osborn in America, and 

 by Lloyd Morgan in England. It may be summed up 

 as follows: 



If the variation appearing by chance should coincide 

 or agree with an identical variation due to the environing 

 conditions, this variation will be reinforced by the double 

 influence. Thenceforward it may be sufficiently marked 

 to allow selection to come in. 



Delage and Goldsmith raise the objection, that ' if 

 the inborn variation is at first too slightly marked 



1 The larva of the insect does not exactly represent the primitive 

 insect, for the larva has undergone important changes following on 

 adaptations necessitated by its modes of existence. But even if we ignore 

 these secondary modifications, there is still undeniably a vast abyss 

 between what the primitive insect was and the evolved insect is. 



TO 



