"F." This is now well known. It was the subject of a paper printed in the proceedings of the Troy Meeting of the American Association many years ago - and the fact that humble bees always do this to any tubular flower they wish to rifle, is generally known now. They don't care one dip of honey for arrangements for cross fertilization - and it has always been a matter of surprise to the writer that so acute an observer as Mr. Darwin should have published what he did about the necessity of bees fertilizing red clover, when, if he had looked more closely, he would have seen that the humble bee does not trouble himself about the floral machinery at all but slits the tube of the clover as you describe in the petunia, and gets the honey from the outside. At least this is the way the Yankee humble bee does, and he may be cuter than his English cousin.