136 The Nature-Study Idea 



may even be true that the poison does protect 

 the plant, but there is no proof thereby that the 

 poison was produced for that purpose. The 

 physiologist may find that the poison in the 

 given case is merely a waste product of some 

 chemical metabolism, and that the plant is for- 

 tunate in getting rid of it. If the plant is now 

 and then protected, the result is an incident. 

 If it should appear that one kind of plant, by 

 natural selection or otherwise, has developed 

 poison in order to protect itself, the fact would 

 be spread abroad in book and magazine, but 

 it would not be stated that it was one case out 

 of a thousand. The exception is enlarged into 

 the rule. 



Persons like to believe in perfect adaptation 

 of means to ends, without a slip or break in the 

 process. They assume that all organisms have 

 definite protectional features. A teacher brought 

 a flower and asked what mechanism it had to 

 insure cross-pollination. I told her that I was 

 not aware that it had any; and she was sur- 

 prised. She asked what mimicry protection a 

 certain animal had; I was obliged to make a 



