St. Nicholas/Volume 40/Number 4/Nature and Science/Clay Jugs
SOME LITTLE CLAY JUGS
Attached to the under side of a protecting leaf and gently rocked by the summer breezes, hang three little jugs. They resemble Mexican water-bottles, but are not made by human hands. Strange as it may seem, they are the work of an insect, the potter-wasp, and are really mud cells that serve as the nest, or home, for the young wasps. While those shown in the illustration were fastened to a maple leaf, they are not al-ways so found, but often are attached singly to twigs.
These little jugs are made of wet clay which the parent wasp gathers for the purpose, and, when thoroughly dry, are hard and enduring. When a jug is finished, it is filled with small spiders or caterpillars, that are first made dormant by the sting of the wasp, but not killed, and in each jug an egg is laid, after which the opening is sealed with a little clay cork.
In a few days, the egg hatches, making a small grub with a big appetite which it at once begins to satisfy with the dormant spiders. The feast 
THE CURIOUS NESTS OF THE POTTER-WASP. continues for about two weeks, when the grub, now grown to a good size, spins a cocoon, and in this state remains for perhaps a few weeks, after which it changes to a full-fledged wasp, and, being no longer content in its confined quarters, it deliberately pushes out the little clay plug that has closed the jug, and goes into the world to take up its work in the great realm of nature. And the little jugs are left deserted and empty.