All the dragon-flies spend the earlier part of their lives in the water. The grubs are very curious creatures and catch their prey in a curious way. Underneath the head is an organ called the mask. This consists of two horny joints, which fold upon one another while not in use. At the end of the second joint is a pair of great sickle-shaped jaws, and when the grub sees a victim it swims quietly underneath it, unfolds the mask, reaches up, and seizes it with the jaws. Then it folds the mask again, and by so doing drags the prisoner down against the true jaws, by means of which it is leisurely devoured. This grub swims, too, in a singular manner. At the end of its body you will notice a short sharp spike. Now this spike really consists of five points, which can be opened out into the form of a star; and in the center of this star is a small round hole, which is really the entrance to a tube running right through the middle of the body. And the grub swims by filling this tube with water, and then squirting it out again with all its force, so that the escaping jet pushes, as it were, against the surrounding water, and drives the insect swiftly forward by the recoil. Dragon-flies are voracious, and always seem to be hungry. They feed entirely upon other insects, and spend almost all their time in chasing and devouring them. The May-fly, or June-fly, also belongs to this order. One sometimes sees it in thousands, dancing, as it were, up and down in the air toward evening on warm spring days, in the neighborhood of water. You can always tell this insect by the three long thread-like bristles at the end of its body. Most people think that this insect only lives for a single day. This, however, is not strictly true, for in damp weather many May-flies live for three or four days. Before they become perfect flies, however, they have lived for nearly two years in the muddy banks of rivers and ponds, in the form of long slender-bodied grubs. These grubs always make their burrows with two entrances, in the form of the letter U turned sideways, so that they can easily leave them without having to turn round. TERMITES