The death of the wasp and hornet workers does not seem to be a matter of cold alone, for, in the regions of perpetual summer, the workers of many species live short lives. They feel the cold, of course, as all our insects do, and inside the nest, on the shelves formed by the flat tops of the combs where the larvæ live, they find dry roosting places at night. The heat of their own bodies materially raises the temperature inside the nest. Though many people think them just alike, the bees and wasps (the hornet is a kind of wasp) are very different creatures. The wasps have trim, slender forms with a few scattered hairs upon their bodies, whereas the bees are generally hairy and short bodied. They both build combs, but the wasps make theirs of paper wetted with saliva, while the bees build theirs of wax secreted from their bodies. The wasps depend upon fresh food gathered in the day's hunt through the air, whereas the bees store up their food in empty cells. The wasps' nests are the wigwams of a season, the bees' hives the more permanent abodes of a higher type of social beings. [Illustration] THE YELLOW JACKET (_Vespa carolina_, Dru.) Who has not wished that these brown and yellow striped creatures would build their nests where people could see them and be warned to stay away, instead of underneath the ground as they do now. They hunt in flocks, and it is no wonder that with the sides of their heads all eyes and with three other eyes on the top of the head they should quickly find anyone who treads on their underground nests. [Illustration] ONE OF THE SOCIAL WASPS (_Polistes metrica_, Say) No insect's nest is better known than the small, hanging, paper comb of this social wasp. You find it under eaves and suspended from the ceiling of the porch and from the rafters of the barn. Then, as the cold days of autumn come and the workers and males of the colony die off, their hibernating queens seek shelter from the cold in our houses. In the spring these queens start out to build a few small, paper cells with finely chewed up fibers of wood wet with sticky saliva. In these they rear up workers to help add new cells and gather food for a new family, and before the summer season has rolled by, the few small paper cells have grown to several scores. If you have the hardihood to stand quite close to one of these nests you will see the grubs with hungry-looking mouths, wiggling and stretching out their necks, each in a cell quite open to the air, waiting to be fed by its sister or the queen. As to which will come forth from these white grubs as queens, which as males, and which are doomed to be but workers--undeveloped females--nobody can foretell, but certain it is that there will be all three of these forms represented. [Illustration] A MUD DAUBER WASP (_Sceliphron cementarium_, Klug) Think of all the marvelous mechanism and chemistry required in order that a wasp may feed its young upon fresh meat!