The little beetle that the caterpillars turn into. It is sitting on its own open-work cocoon, from which it has just hatched out. The picture makes it about twice its real size

You will wonder, I expect, why the Mother Wasp troubles to make the little tube above the hole. I think I can tell you one reason and you must remember this, because it was just by chance that I found it out. One hot morning in June I watched Mother Spinipes bringing seven caterpillars to her hole. Then a heavy thunderstorm came on, and the rain came down in buckets, and I had to run away for shelter. Late in the evening when it had cleared up a little, I thought I would like to see what had happened to the tube I had been watching, and I went back to the place and found that the rain had knocked it all to pieces. But I saw something much more interesting than this. The tube had been on the face of a sand-cliff, and in a crack close by there was an ants' nest. I found that the ants were running down the wasp's hole and bringing out the caterpillars as fast as they could (I saw them take six away), and taking them along the face of the cliff into their own stronghold. Now the tube that stands out from the sand somehow frightens the ants (I never saw an ant climb out along the tube and down inside it), and so I think that one of the reasons for the tube must be that it keeps away ants and creatures of that kind who crawl about on the face of the sand cliff and like eating caterpillars.

BEFORE THE THUNDERSTORM

AFTER THE THUNDERSTORM

This is a large picture of Crabro, about twice as big as she really is