In such hives, when the temperature out of doors falls suddenly and severely, the bees at once feel the unfavorable change; they are obliged in self defence to huddle together to keep warm, and thus large portions of the brood comb are often abandoned, and the brood either destroyed at once by the cold, or so enfeebled that they never recover from the shock. Let every bee keeper, in all his operations, remember that brood comb must never be exposed to a low temperature so as to become chilled: the disastrous effects are almost as certain, as when the eggs of a setting hen are left, for too long a time, by the careless mother. The brood combs are never safe when taken for any considerable time from the bees, unless the temperature is fully up to summer heat. "[4]The young bees break their envelope with their teeth, and assisted, as soon as they come forth, by the older ones, proceed to cleanse themselves from the moisture and exuviæ with which they were surrounded. Both drones and workers on emerging from the cell are, at first grey, soft and comparatively helpless so that some time elapses before they take wing. "With respect to the cocoons spun by the different larvæ, both workers and drones spin _complete cocoons_, or inclose themselves on every side; royal larvæ construct only _imperfect cocoons_, open behind, and enveloping only the head, thorax, and first ring of the abdomen; and Huber concludes, without any hesitation, that the final cause of their forming only incomplete cocoons is, that they may thus be exposed to the mortal sting of the first hatched queen, whose instinct leads her instantly to seek the destruction of those who would soon become her rivals. "If the royal larvæ spun complete cocoons, the stings of the queens seeking to destroy their rivals might be so entangled in their meshes that they could not be disengaged. 'Such,' says Huber, 'is the instinctive enmity of young queens to each other, that I have seen one of them, immediately on its emergence from the cell, rush to those of its sisters, and tear to pieces even the imperfect larvæ. Hitherto philosophers have claimed our admiration of nature for her care in preserving and multiplying the species. But from these facts we must now admire her precautions in exposing certain individuals to a mortal hazard.'" The cocoon of the royal larva is very much stronger and coarser than that spun by the drone or worker, its texture considerably resembling that of the silk worm's. The young queen does not come forth from her cell until she is quite mature; and as its great size gives her abundant room to exercise her wings she is capable of flying as soon as she quits it. While still in her cell she makes the fluttering and piping noises with which every observant bee keeper is so well acquainted.