The cells designed to contain the worker-brood measure one-fifth of an inch across the mouth; drone cells are larger, having a diameter of a quarter-inch, as well as greater depth. The queen may pass from one species of comb to the other, but she seldom makes a mistake. The egg deposited in the worker-cell hatches out a female; that which is laid in the larger cell becomes a drone, or male bee. Obviously the deposition of the different kinds of eggs is well under the control of the queen. It will be also seen that not only does the mother bee lay either male or female eggs at will, but their number also is subject to her discrimination. From the time when she begins ovipositing, until she reaches her period of greatest activity in early summer, the increase of the colony is not regular, but goes by fits and starts according to the weather, or the amount of incoming food. If the new honey is steadily mounting up in the storehouse, and pollen is plentiful, the work of brood-raising will go freely ahead; but if unseasonable cold stops the work of the foragers, this will immediately affect the output of the queen, and under exceptionally adverse conditions egg-laying may be entirely arrested. This may also take place in the height of the season, and in full favour of sunshine and plenty, if the hive is a small one, and the limit of its capacity has been reached. The combs will then be full of either honey or brood, and the queen must wait until laying space can be cleared for her. That she is able to do this—that her powers can be augmented or restrained, according to the needs of the colony, and that the proportion of the sexes in the hive can be varied at will to suit like contingencies—can only be understood when the details of her life-history have been passed under review. In the normal, prosperous colony, which we are now studying, the queen will be in her prime, and under natural conditions will remain at the head of affairs until she goes out with the first swarm in May or June. A queen-bee is at the zenith of her fecundity in the second year of her life. After that, her egg-laying powers steadily decline, although she may live to be four, or even five, years old. But the authorities in a hive rarely allow a mother-bee to retain her position after she has shown signs of waning energy. Preparations are at once set on foot for the raising of another queen.