Any manipulation for swarm control, whether applied after the colony has acquired the "swarming fever" or applied to all colonies alike previous to the swarming season, is based upon the single principle--_a temporary disturbance in the continuity of the daily emergence of brood_. This disturbance should occur just previous to or during the swarming season. In natural swarming the brood and the swarm are separated, the swarm being without hatching brood during a period of three weeks. The brood from which the swarm came may be allowed to emerge in a separate hive and the resulting bees may then be returned to the swarm (p. 29). In this way the swarming instinct is satisfied, at least temporarily, without materially decreasing the population of the colony. The beekeeper may anticipate swarming by removing the brood from the hive, allowing it to emerge in a separate hive and finally returning these young bees to the colony in the same manner as is done with the natural swarm. Under the same conditions the subsequent behavior of a colony treated in this way is similar to that of a natural swarm. In either case there has been a break in the continuity of the emergence of young bees in the hive during a period of three weeks. Instead of hiving a natural swarm upon empty combs or frames of foundation, combs of emerging brood (without queen cells) taken from a colony that has been queenless during a period of 10 to 15 days may be used (p. 33) and a similar condition may be had without swarming by removing all of the brood and substituting such combs of emerging brood, thus at least temporarily avoiding swarming. In these cases there is a break of 10 to 15 days in the continuity of the daily emergence of bees. A similar interruption of brood rearing may be accomplished by removing the queen from the hive or caging her within the hive during a period of 10 days or 2 weeks, then returning her to the combs. In this case no queen cells must of course be allowed to mature. A condition similar to this may be obtained without removing the queen by dividing the brood chamber into two parts with queen-excluding metal, for a period of 10 to 15 days. The brood from the division containing the queen is then removed and the bees, together with the queen, shaken into the other (queenless) division, the queen cells if any being first destroyed. The brood thus removed may later be returned to the colony in the form of young bees in the usual manner (p. 29). Even the destruction of the sealed brood by uncapping it has been advised as a means of swarm control. This gives a period of about 12 days during which few or no young bees emerge. These methods are illustrative of the principle employed in the various methods of control by manipulation, which may be classified under three general headings: (1) Taking the queen from the hive. (2) Taking the brood from the hive. (3) Separating the queen and brood within the hive.