To keep up a necessary supply of air in the hive, and to prevent suffocation from heat, a certain number of the community are employed in fanning the passages between the cakes of comb and the whole interior of the hive, by the vibration of their wings, which thoroughly ventilates it, and the accumulation of deleterious air is prevented; some, for this purpose, being posted at the aperture to the hive, where, this vibration causing a temporary vacuum, the external air rushes in, and the chain of succession of bees within becoming thus vibrating air-valves completes the ventilating arrangement. While all these operations are progressing, a certain number are acting as a militia of citizens, who have substitutes only in the succession and change of duties. These act as sentinels, who guard the entrance and patrol the interior and courageously intercept all inimical intrusion, for the bees have many enemies, but who are merely so to benefit themselves, and are not parasites of the nature of the bee-parasites of the solitary kinds; and where they cannot individually avert it, they obtain collateral aid from others of their staff. The next class is the attendants upon the queen: these vary in number from twelve to twenty; they invariably accompany her wherever she proceeds throughout the hive, for the purpose of laying her eggs; and whether their custom gave rise to the etiquette which attends human royalty, that a subject may never turn the back upon the sovereign, these attendant bees surround her with the head always turned towards her, and seem to caress her with their antennæ and pay her every kind of deferential homage, those in front moving backwards as she advances, and those on each side, laterally, so that they ever face her; and as they tire others succeed them in their duties. Another set fulfil the office of keeping the hive thoroughly clean, for the transit of such large numbers will inevitably collect occasional dirt, as will the drift of the wind at the entrance of the hive and the action of the ventilators themselves. Their duty it is also to remove any extraneous organic body that has forcibly entered and which may have succumbed to the vindictiveness of the bees. Where they are not strong enough, even collectively, to effect the removal, as in the case of a mouse or anything else as large or larger, they then call to their aid the wax workers and the repairers; these enclose the obnoxious body, which they have the judgment to know will become dangerous from putrefaction, to aid in its prevention, by a cerement of wax or propolis, which prevents any offensive exhalation, and thus secures the wholesomeness of the hive. Here is completed, with the enumeration of those which successively repose from their toil, the several labours of the community which inhabits the hive.