FIELD AND STUDY 



female wasp can at will determine the sex of her 

 egg at the instant of laying. Here again we see her 

 superhuman knowledge. She can begin with eggs 

 that will produce males or fefliales, just as she 

 chooses, and since she cannot change the order of 

 their succession in her ovaries, she must determine 

 their sex by the power of her will at the time of lay- 

 ing. Since the females require more space and more 

 food than the males, the mother must know the sex 

 of the egg which she is going to lay while in the act 

 of laying it. 



The hive bee can change the sex of the egg — 

 turn a worker bee into a queen bee — by changing 

 the size and position of the cell, and changing the 

 food in quantity and in kind. Something like this 

 may take place in the case of the wasp referred to. 



Insects of all kinds possess the knowledge and 

 skill that it is necessary for them to have. Thus 

 "the leaf -roller requires for her young a leaf ren- 

 dered flexible ad hoc, half-alive, paralyzed in a 

 fashion, a leaf that can be easily shaped into a 

 scroll," and she knows just what to do to attain 

 this end, as well as the wasp knows how to paralyze 

 her cricket or spider — she inserts her drill into the 

 petiole of the leaf, there and nowhere else, and thus 

 without much trouble she affects the resin of the 

 aqueduct. 



Different species of insects at times display the 

 most amazing ignorance in regard to their natural 

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