Reflexes, Instincts, and Intelligence 647 



way in which it is constructed. Besides, as I think I have already proved, 

 it is very doubtful, considering the manner in which she acted, whether the 

 Sphex would return to use the dwelling which she had prepared. A new 

 ephippiger will be caught elsewhere, and elsewhere too will the storehouse 

 destined for it be hollowed. As, however, these are but conclusions drawn 

 by reasoning, let us consult experiment, more conclusive here than logic: I 

 let nearly a week pass in order to allow the Sphex to return to the burrow so 

 methodically closed, and use it if she liked for her nest-laying. Events 

 answered to the logical deduction; the burrow was just as I had left it, well 

 closed, but without food, egg, or larva. The demonstration was decisive; 

 the Sphex had not returned. 



"Thus we see the plundered Sphex go into her house, pay a leisurely 

 visit to the empty chamber, and the ne.xt moment behave as if she had not 

 perceived the absence of the big prey which a little while before had encum- 

 bered the cell. Did she not realize 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 

 ver)' 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 ne.xt, 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 inter- 

 est. What object could there be in stopping a burrow now useless, since it 

 no longer contained prey and egg, and which will remain useless, since the 

 Sphex will not return to it ? One can only explain this irrational proceeding 

 by regarding 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 labor. 



"Third experiment. — To know all and nothing, according as the condi- 

 tions are normal or otherwise, is the strange antithesis presented by the in- 

 sect. Other examples drawn from the Sphegidac will confirm us in this prop- 

 osition. Sphex albiseda attacks middle-sized Acridians, the various species 

 scattered in the neighborhood of her burrow all furnishing a tribute. From 

 the abundance of these Acrididae the chase is carried on near at hand. When 

 the vertical well-like burrow is ready, the Sphex merely flies over the ground 

 near, and espies an Acridian feeding in the sunshine. To pounce and sting 



