XII THE IGNORANCE OF INSTINCT 173 



and the next moment behave as if she had not 

 perceived the absence of the big prey which a 

 little while before had encumbered the cell. Did 

 she not realise the absence of food and egg ? Was 

 she really so dull — she, so clear-sighted when playing 

 the murderer — that the cell was empty? I dare 

 not accuse her of such stupidity. She did perceive 

 it. But why then that other piece of stupidity 

 which made her close, and very conscientiously too, 

 an empty chamber which she did not mean to store? 

 It was useless — downright absurd — to do this, and 

 yet she worked with as much zeal as if the future 

 of the larva depended on it. The various instinctive 

 actions of insects are then necessarily connected ; 

 since one thing has been done, such another must 

 inevitably follow to complete the first, or prepare 

 the way for the next, and the two acts are so 

 necessarily linked that the first must cause the second, 

 even when by some chance this last has become 

 not only superfluous, but sometimes contrary to the 

 creature's interest. What object could there be in 

 stopping a burrow now useless, since it no longer 

 contained prey and eggy and which will remain 

 useless, since the Sphex will not return to it ? One 

 can only explain this irrational proceeding by re- 

 garding it as the necessary consequence of preceding 

 actions. In the normal state of things the Sphex 

 hunts her prey, lays an egg, and closes the hole. 

 The prey has been caught, the egg laid, and now 

 comes the closing of the burrow, and the insect 

 closes it without reflecting at all, or guessing the 

 fruitlessness of her labour. 



Third experiment. — To know all and nothing. 



