42 EXPERIMENTAL EVOLUTION LECT. 



note the present condition of things, and let our de- 

 scendants do the same and draw their conclusions. 

 So far as psychology is concerned, they may answer 

 that proofs of individual evolution are to be seen every 

 day, and that mental evolution is a positive fact in 

 every individual man, and in the animal kingdom as 

 a whole. And as concerns zoology, they may reply 

 that innumerable facts point to descent and evolution. 

 But the creationists may object to this argument, 

 and say ; if species are really evolved from each 

 other and the case of species is only a very small 

 point in the question you must show us species aris- 

 ing, by evolution, from former species. In many 

 palaeontological cases we do not find the connecting 

 links of which you assume the existence in fact, it 

 may be said with truth that their existence is not 

 always* required and, especially, we have not yet 

 seen a new species originate from a preceding one. 

 Show us this, show us a positive case of transmuta- 

 tion through natural means, such as may and do 

 operate under natural conditions, show us a species 

 becoming a new one, hitherto unknown? and we 

 will believe in evolution. Such is the answer of 

 creationists. 



It might be discussed whether this argument is not 



1 This requirement is necessary to preclude all objection which might 

 be raised with reason from the possibility of normal dimorphism. 



