Another very remarkable circumstance, which this experiment gave me occasion to observe, consists in the good reception given by the bees to the stranger queen, while they still preserved the first. Having so often seen the symptoms of discontent that a plurality of queens occasions, after having witnessed the clusters formed around these supernumerary queens to confine them, I could not expect they would pay the same homage to a second mutilated one they still testified towards the first. Is it because after losing the antennæ, these queens have no more any characteristic which distinguishes the one from the other?
I was the more inclined to admit this conjecture from the bad reception of a third fertile queen preserving her antennæ, which was introduced into the same hive. The bees seized, bit her, and confined her so closely, that she could hardly breath or move. Therefore, if they treat two females deprived of antennæ in the same hive equally well, it is probably because they experience the same sensation from these two females, and want the means of longer distinguishing them from each other.
From all this, I conclude, that the antennæ are not a frivolous ornament to insects, but, according to all appearance, are the organs of touch or smell. Yet I cannot affirm which of these senses reside in [them.] It is not impossible that they are organised in such a manner as to fulfil both functions at once.
As in the course of this experiment both mutilated females constantly endeavoured to escape from the hive, I wished to see what they would do if set at liberty, and whether the bees would accompany them in their flight. Therefore I removed the first and third queen from the hive, leaving the fertile mutilated one, and enlarged the entrance.
The queen left her habitation the same day. At first she tried to fly, but, her belly being full of eggs, she fell down and never attempted it again. No workers accompanied her. Why, after rendering the queen so much attention while she lived among them, did they abandon her now on her departure? You know, Sir, that queens governing a weak swarm are sometimes discouraged, and fly away, carrying all their little colony along with them. In like manner sterile queens, and those whose dwelling is ravaged by weevils, depart; and are followed by all their bees. Why therefore in this experiment did the workers allow their mutilated queen to depart alone? All that I can hazard on this question is a conjecture. It appears that bees are induced to quit the hives from the increased heat which occasions the agitation of their queen, and the tumultuous motion which she communicates to them. A mutilated queen, notwithstanding her delirium, does not agitate the workers, because she seeks the uninhabited parts of the hive, and the glass panes of it: she hurries over clusters of bees, but the shock resembles that of any other body, and produces only a local and instantaneous motion. The agitation arising from it, is not communicated from one place to another, like that produced by a queen, which in the natural state wishes to abandon her hive and lead out a swarm; there is no increased heat, consequently nothing that renders the hive insupportable to her.
This conjecture, which affords a tolerable explanation why bees persist in remaining in the hive, though the mutilated queen has left it, is no reason for the motive inducing the queen herself to depart. Her instinct is altered; that is the whole that I can perceive. I can discern nothing more. It is very fortunate for the hive, that this queen departs, for the bees incessantly attend her; nor do they ever think of procuring another while she remains; and if she was long of leaving them, it would be impossible to replace her; for the workers worms would exceed the term at which they are convertible into royal worms, and the hive would perish. Observe, that the eggs dropped by the mutilated queen can never serve for replacing her, for, not being deposited in cells, they dry and produce nothing.
I have yet to say a few words on females laying male eggs only. M. Schirach supposes that one branch of their double ovary suffers some alteration. He seems to think that one of these branches contains the eggs of males, while the other has none but common eggs, and as he ascribes the inability of certain queens to lay the latter to some disease, his conjecture becomes very plausible. In fact, if the eggs of males and workers are indiscriminately mixed in both branches of the ovary, it appears at first sight that whatever cause acts on that organ, it should equally affect both species of eggs. If on the contrary, one branch is occupied by the eggs of drones only, and the other contains none but common eggs, we may conceive how disease affects the one, while the other remains untouched. Though this conjecture is probable, it is confuted by observation. We lately dissected queens, which laid none but male eggs, and found both branches of the ovary equally well expanded, and equally sound, if I may use the expression. The only difference that struck us was that in these two branches, the eggs were apparently not so close together as in the ovaries of queens laying both kinds of eggs.
Pregny, 12. September 1791.
LETTER XIII.
ECONOMICAL CONSIDERATIONS ON BEES.
In this letter I shall treat of the advantages that may be derived from the new invented hives, called book or leaf hives, in promoting the economical knowledge of bees.