Of what is Pelopæus thinking as, humming loudly, she jams her paralyzed and benumbed victims into her little cylindrical tubes? If only we could get inside of that little head! If only we could be wasps for a day, and then come back and tell about it, how much vain speculation would be saved! We can understand her when she soars gayly into the blue, the sunshine flashing from her brilliant wings; we too have felt the delight of health and freedom. She is still comprehensible when, at the close of day, she and her sisters quarrel for the favorite sleeping–places among the carvings of the porch pillars; but we cannot follow her mental processes when, at the moment of building, she surrenders herself to the mysterious sway of instinct, doing she knows not what, but doing it joyously, and preserving through it all the precious possession of her own individuality. Every aspect speaks of pleasure as these wasps gather at well or spring, and, singing contentedly, stand on their heads to gather their loads of mud. Briskly and gayly they fly back and forth, pausing at the nest long enough to pat the soft building material into shape. A single load makes half a ring at the larger part of the nest or a whole one at the bottom; and since one dries before the next is put on, the contour of each ring is visible when the tube is done, giving a very artistic effect. This is only accident, however; the wasp cares nothing about the beauty of the structure, for her next step is to daub the whole with lumps of mud, the walls being thus thickened and strengthened. About forty loads are necessary for each cell, and to build and provision one is a good day’s work. It is strange enough that with no one to teach her Pelopæus knew how to make her cell; but now she must do her hunting, and it is stranger still that she should be impelled to catch nothing but spiders. How does she know a spider from a fly, and why should she prefer one to the other? Not so unreasonable as some wasps, however, she demands nothing further than that her prey shall belong to this great group, and passes lightly over differences of species and genera. Her powerful sting fits her to cope with anything she may meet; but as the size of the cell must be taken into consideration, and the victim must be carried home on the wing, she is on the lookout for something not too large. Here then she ceases to be an automaton, and to some extent makes use of her wits. How does Pelopæus seize her spider? When and how many times is it stung? Is the wound given with discrimination, a certain point in the ganglion being pricked, so that the spider may be paralyzed, but not killed? Is there any malaxation?