HABITS OF SOCIAL WASPS.—We have already briefly noticed the way in which a colony of wasps is founded, but some further particulars as to the mode in which the society is increased and developed may be mentioned. The queen-wasp makes at first only a very small group of three or four incomplete cells; each cell is at first circular, or nearly so, and moreover is of smaller diameter than it will afterwards be. In each of the first three or four incomplete cells an egg is laid, and more cells are commenced; but as the eggs soon hatch and produce larvae that grow rapidly, the labours of the queen-wasp are chiefly directed to feeding the young. At first she supplies them with saccharine matter, which she procures from flowers or fruits, but soon gives them a stronger diet of insect meat. This is procured by chasing living Insects of various kinds. Some species of wasps prefer particular kinds of Insects, and the hornet is said to be very fond of the honey-bee, but as a rule Diptera are the prey selected. When an Insect has been secured, the hard and innutritious parts are bitten off, and the succulent parts, more especially the thorax which contains chiefly muscular tissue, are reduced to a pulp by means of the mandibles; this is offered to the larvae, which are said to stretch out their heads to the mother to receive the food, after the manner of nestling birds. When a larva is full grown it spins a cocoon in the cell and changes to a pupa. It is said by some entomologists that the queen-wasp closes the cell for the purpose of the larval metamorphosis; but this is contradicted by others, and is probably erroneous. In about a month, or a little less, from the time of deposition of the egg, the perfect Insect is ready for issue, and almost immediately after leaving its cell it assists in the work that is going on for the development of the society. The {85}Insects produced at this early period of the colony are exclusively workers, _i.e._ imperfect females. They relieve the queen of the task of supplying the larvae with food, and she henceforth remains within the nest, being, it is said, herself fed by her workers; the society now rapidly increases in numbers, and fresh combs are formed, the upper layer being always the oldest. About the month of August, cells of larger size than those that have previously been constructed are formed, and in these males and perfect females are produced; in a few weeks after this the colony languishes and becomes extinct. When it is no longer possible for the enfeebled wasps to carry out their tasks of feeding the brood, they drag the larvae out of the cells and destroy them. An uncertain number of queen-wasps seek protected nooks in which to pass the winter, and each of these queens may be the founder of a nest in the ensuing spring. It should be remarked that de Saussure states that all the intermediate grades between perfect and imperfect females exist, and Marchal's recent observations confirm this.