lay only the eggs of males, not to
be deceived by these circumstances, and expect that eggs of males will
be deposited in the workers cells.

It is a singular fact, that the females, whose fecundation has been
retarded, sometimes lay the eggs of males in royal cells. I shall prove,
in the history of swarms, that immediately when queens, in the natural
state, begin their great laying of male eggs, the workers construct
numerous royal cells. Undoubtedly, there is some secret relation between
the appearance of male eggs and the construction of these cells; for it
is a law of nature from which bees never derogate. It is not surprising,
therefore, that such cells are constructed in hives governed by queens
laying the eggs of males only. It is no longer extraordinary that these
queens deposit in the royal cells, eggs of the only species they can
lay, for in general their instinct seems affected. But what I cannot
comprehend is, why the bees take exactly the same care of the male eggs
deposited in royal cells, as of those that should become queens. They
provide them more plentifully with food, they build up the cells as if
containing a royal worm; in a word, they labour with such regularity
that we have frequently been deceived. More than once, in the firm
persuasion of finding royal nymphs, we have opened the cells after they
were sealed, yet the nymph of a drone always appeared. Here the instinct
of the workers seemed defective. In the natural state, they can
accurately distinguish the male worms from those of common bees, as they
never fail giving a particular covering to the cells containing the
former. Why then can they no longer distinguish the worms of drones when
deposited in the royal cells? The fact deserves much attention. I am
convinced that to investigate the instinct of animals, we must
carefully observe where it appears to err.

Perhaps I should have begun this letter with an abstract of the
observations of prior naturalists, on queens laying none but the eggs of
males; however, I shall here repair the omission.

In a work, _Histoire de la Reine des Abeilles_, translated from the
German by _Blassiere_, there is printed a letter from M. Schirach to
you, dated 15 April 1771, where he speaks of some hives, in which the
whole brood changed into drones. You will remember that he ascribes this
circumstance to some unknown vice in the ovaries of the queen; but he
was far from suspecting that retarded fecundation had