Some of the nests made by vespa ([Fig. 353]), as the hornets or yellow-jackets are called, are very large. Do you think a wasp could make one alone? No, these are social wasps; that is, a great many live together. There are males, females, and workers. Some day we shall tell you how the wasps form their colony, but for this lesson we want you to study the nest.
Notice the envelope which covers the cells. How many layers of paper are there in it? We might call each layer a clapboard.
Can you see any difference in the direction of the outside layers on top of the nest and those which are below?
Fig. 354. Interior arrangement of white-faced hornet's nest.
How many stories high is the nest?
Note the difference in the size of the stories. Where do you find the smallest?
Count the rooms or cells in each.
You know, of course, that an egg is placed in each cell. When the larvæ, as the young of the wasps are called, are hatched, they still live in the cells.
How do they manage to keep in their cells? You see the nest is really turned upside down. Their little heads must hang where the worker wasps can feed them easily. I wonder whether you can tell me why the young wasps do not fall out?