Then she did the most wonderful thing. With her fore feet she pawed and raked the surface until it was quite smooth, and with her jaws and horny head she pressed down and tamped the fine bits of soil until they were a little below the surface of the salt crust around the hole, and then she brought again the little circular lid or top of salt crust and carefully put it in the little depression on the top of the filled-in burrow, so that it fitted perfectly with the hard uncut salt crust around the hole's edge! This is true. Does it seem wonderful to you? Why? Because we think that other animals cannot do what would be a very simple thing indeed for us? Our wasp was evidently concealing the whereabouts of her worm-stored burrow. I don't say that she _wanted_ to conceal it; or _decided_ to conceal it; or even _intended_ to conceal it. She was simply, I say, concealing it. That seems quite certain, doesn't it? Well, this action of cutting out and replacing the bit of salt crust over the burrow was about the simplest and most effective way of concealing the hole that could be reasoned out, if we ourselves were to undertake it. The wasp, and all the other wasps of the same kind in our marshes, concealed their holes in the way that our reason would suggest to us as the best way. But I do not say anything about the wasp's mental processes toward getting at this behavior. One thing is pretty sure. Among a score or hundred of us doing this work, there would be pretty sure to be some to do it in a different sort of way from the others. The wasps of the same kind all do it alike. Perhaps that is the chief difference between reason and instinct.