266 THE WONDERS OF INSTINCT 



circumstances require it, the order of the laying can be 

 reversed and begin with males; lastly, the entire laying 

 can contain only one sex. 



The same privilege is possessed by the predatory 

 Hymenoptera, the Wasps, at least by those in whom the 

 two sexes are of a different size and consequently require 

 an amount of nourishment that is larger in the one case 

 than in the other. The mother must know the sex of the 

 egg which she is going to lay ; she must be able to choose 

 the sex of that egg so that each larva may obtain its 

 proper portion of food. 



Generally speaking, when the sexes are of different 

 sizes, every insect that collects food and prepares or 

 selects a dwelling for its offspring must be able to choose 

 the sex of the egg in order to satisfy without mistake the 

 conditions imposed upon it. 



The question remains how this optional assessment 

 of the sexes is effected. I know absolutely nothing about 

 it. If I should ever learn anything about this delicate 

 point, I shall owe it to some happy chance for which I 

 must wait, or rather watch, patiently. 



Then what explanation shall T give of the wonderful 

 facts which I have set forth? Why, none, absolutely 

 none. I do not explain facts, I relate them. Growing 

 daily more skeptical of the interpretations suggested to 

 me and more hesitating as to those which I myself may 

 have to suggest, the more I observe and experiment, the 

 more clearly I see rising out of the black mists of possi- 

 bility an enormous note of interrogation. 



Dear insects, my study of you has sustained me and 



