Under a warm climate, where flowers abound, the hives may cast several times in succession. The first swarm, however, is always the best. It is more numerous, and has before it more time to provision itself. If the weather remains favourable, it is not rare to see it send out a swarm itself three weeks after leaving the old hive. The old queen then leads the emigration of the second swarm, abandoning the colony she had lately founded. If the original hive sends forth several swarms, the interval between the first and the second is from seven to ten days; the third and the fourth follow at shorter intervals. But these late casts have rarely vitality enough to exist long. [Illustration: Fig. 322.--Cluster of Bees hanging to a branch.] A swarm never returns to a hive it has once left. It is surprising then that a hive can furnish a second swarm after the interval of a few days, without being too much weakened. But the old queen, in quitting her domain, leaves behind her a considerable quantity of brood. These larvæ are not long in re-peopling the hive, so as to furnish a second swarm. The third and the fourth casts weaken the population more perceptibly; but there remain still enough workers to continue operations. In some cases the agitation of the cast is so great as to cause all the bees to quit the hive together, leaving it deserted; but this desertion only lasts an instant, one part of the swarm wisely returning to their home. All those which start away become members of the new colony. When the general delirium we have spoken of has taken possession of them, they precipitate themselves together, they pile themselves up all at the same time by the door of the hive, and get so hot as to perspire freely. Those which are in the midst of the _mêlée_ bear the weight of the whole crowd, and seem bathed in sweat. Their wings become damp, and they are no longer able to fly, and even if they manage to escape, they get no further than the stand, and are not long in re-entering the hive, instead of following the main body of the emigrants. We must not forget that a part of the population is always out at those hours of the day when the swarms take place, engaged in collecting provisions; and having collected the spoil, these workers return to the hive abandoned by the greater part of their companions, and betake themselves to their usual occupations, as if nothing had happened. They form the nucleus of the new population, which is soon enlarged by the hatching of the pupæ. We have already said that the first swarm is always led by the old queen or mother, and that it starts before the hatching of the young females. If she had not gone out before their birth she would have destroyed them, and the new hive would have been unable to re-organise itself for the want of a chief.