queen several days, and that the bees had no mean of replacing her,
there being no workers' worms. I then provided them with a small portion
of comb, each cell containing a young worm of the working species. Next
day, the bees prolonged several cells around the worms destined for
queens, in the form of royal ones. They also bestowed some care on the
worms in the adjoining cells. Four days afterwards, all the royal cells
were shut, and we counted nineteen small cells also perfected and closed
by a covering almost flat. In these were worms that had not received the
royal treatment; but as they had lived in the vicinity of the worms
destined for replacing the queens, it was very interesting to follow
their history, and necessary to watch the moment of their last
transformation. I removed the nineteen cells into a grated box, which
was introduced among the bees. I also removed the royal cells, for it
was of great importance, that the queens they would produce should not
disturb or derange the result of the experiment. But here another
precaution was also requisite. It was to be feared, that the bees being
deprived of the produce of their labour, and the object of their hope
might be totally discouraged; therefore, I supplied them with another
piece of comb, containing the brood of workers, reserving power to
destroy the young brood when necessary. This plan succeeded admirably.
The bees, in bestowing all their attention on these last worms, forgot
those that had been removed.
When the moment of transformation of the nymphs in the nineteen cells
arrived, I examined the grated box frequently every day, and at length
found six bees exactly similar to _common bees_. The worms of the
remaining thirteen had perished without changing.
The portion of brood comb that had been put into the hive to prevent the
discouragement of the bees was then removed. I put aside the queens
produced in the royal cells; and having painted the thorax of the six
bees red, and amputated the right antenna, I transferred the whole six
into the hive, where they were well received.
You easily conceive my object, Sir, in this course of observations. I
knew there was neither a large nor small queen in the hive: therefore,
if, in the sequel, I should find new laid eggs in the combs, how very
probable must it be that they had been produced by some of the six bees?
But, to attain absolute certainty, it was necessary to take them in the
act of laying. Some ineffaceable mark was also required for
distinguishing them in particular.
This proceeding was attended with the most ample success. We soon found
eggs in the hive; their number increased daily; and their worms were all
drones. But a long interval elapsed before we could take the bees that
laid them. At length, by means of assiduity and perseverance, we
perceived one introducing the posterior part into a cell; we opened the
hive, and caught the bee: We saw the egg it had deposited, and by the
colour of the thorax, and privation of the right antenna, instantly
recognised that it was one of the six that had passed to the vermicular
state in the vicinity of the royal cells.
I could no longer doubt the truth of my conjecture; at the same time, I
know not whether the truth will appear as rigorous to you, Sir, as it
does to myself. But I reason in the following manner: If it is certain
that fertile workers are always produced in the vicinity of royal cells,
it is no less true, that in itself, the vicinity is indifferent; for the
size and figure of these cells can produce no effect on the worms in
those surrounding them; there must be something more; we know that a
particular aliment is conveyed to the royal cells; we also know, that
this aliment has a very powerful effect on the ovaries; that it alone
can unfold the germ. Thus, we must necessarily suppose the worms in the
adjacent cells have had a portion of the same food. This is what they
gain, therefore, by vicinity to the royal cells. The bees, in their
course thither, will pass in numbers over them, stop and drop some
portion of the jelly destined for the royal larvæ. This reasoning, I
presume, is consistent with the principles of sound logic.
I have repeated the experiment now described so often, and weighed all
the concomitant circumstances with so much care, that whenever I please,
I can produce fertile workers in my hives. The method is simple. I
remove the queen from a hive; and very soon the bees labour to replace
her, by enlarging several cells, containing the brood of workers, and
supplying the included worms with the royal jelly. Portions of this
aliment also fall on the young larvæ deposited in the adjacent cells,
and it unfolds the ovaries to a certain degree. Fertile workers are
constantly produced in hives where the bees labour to replace their
queen; but we very rarely find them, because they are attacked and
destroyed by the young queens reared in the royal cells. Therefore, to
save them, all their enemies must be removed, and the larvæ of the royal
cells taken away before undergoing their last metamorphoses. Then the
fertile workers, being without rivals at the time of their origin, will
be well received, and, by taking the precaution to mark them, it will be
seen, in a few days, that they produce the eggs of males. Thus, the
whole secret of this proceeding consists in removing the royal cells at
the proper time; that is, after being sealed, and previous to the young
queens leaving them{K}.
I shall add but a few words to this long letter. There is nothing so
very surprising in the production of fertile workers, when we consider
the consequences of M. Shirach's beautiful discovery. But why do they
lay male eggs only? I can conceive, indeed, that the reason of their
laying few is from their ovaries being but imperfectly expanded, but I
can form no idea why all the eggs should be those of males, neither can
I any better account for their use in hives; and hitherto, I have made
no experiments on their mode of fecundation.
_PREGNY, 25. August 1791._
FOOTNOTES:
{I} It is difficult to discover whether the author thinks, as some
naturalists, that bees are instrumental in hatching the eggs.--T.
{J} The original is extremely confused in the preceding passages.--T.
{K} I have frequently seen queens, at the moment of production, begin
first by attacking the royal cells and then the common ones beside them.
As I had not seen fertile workers when I first observed this fact, I
could not conceive from what motive the fury of the queen was thus
directed towards the common cells. But now I know they can distinguish
the species included, and have the same instinctive jealousy or aversion
towards them as against the nymphs of queens properly so denominated.
LETTER VI.
_ON THE COMBATS OF QUEENS: THE MASSACRE OF THE MALES: AND WHAT SUCCEEDS
IN A HIVE WHERE A STRANGER QUEEN IS SUBSTITUTED FOR THE NATURAL ONE._
M. de Reaumur had not witnessed every thing relative to bees when he
composed his history of these industrious animals. Several observers,
and those of Lusaçe in particular, have discovered many important facts
that escaped him; and I, in my turn, have made various observations of
which he had no suspicion: at the same time, and this is a very
remarkable circumstance, not only has all that he expressly declares he
saw been verified by succeeding naturalists, but all his conjectures are
found just. The German naturalists, Schirach, Hattorf, and Riems
sometimes contradict him, indeed, in their memoirs; but I can maintain
that, while combating the opinion of M. de Reaumur, it is they who are
almost always wrong; of which several instances might be adduced.
What I shall now proceed to say will give me an opportunity of detailing
some interesting facts.
It was observed by M. de Reaumur, that when any supernumerary queen is
either produced in a hive, or comes into it, one of the two soon
perishes. He has not actually witnessed the combat in which she falls,
but he conjectures there is a mutual attack, and that the empire remains
with the strongest or the most fortunate. M. Schirach, on the other
hand, and, after him, M. Riems, thinks that the working bees assail the
stranger, and sting her to death. I cannot comprehend by what means they
have been able to make this observation: as they used very thick hives
only, with several rows of combs, they could at most but observe the
commencement of hostilities. While the combat lasts, the bees move with
great rapidity; they fly on all sides; and, gliding between the combs,
conceal their motions from the observer. For my part, though using the
most favourable hives, I have never seen a combat between the queens and
workers, but I have very often beheld one between the queens themselves.
In one of my hives in particular, there were five or six royal cells,
each including a nymph. The eldest first underwent its transformation.
Scarcely did ten minutes elapse from the time of this young queen
leaving her cradle, when she visited the other royal cells still close.
She furiously attacked the nearest; and, by dint of labour, succeeded
in opening the top: we saw her tearing the silk of the coccoon with her
teeth; but her efforts were probably inadequate to the object, for she
abandoned this end of the cell, and began at the other, where she
accomplished a larger aperture. When it was sufficiently enlarged, she
endeavoured to introduce her belly, and made many exertions until she
succeeded in giving her rival a deadly wound with her sting. Then having
left the cell, all the bees that had hitherto been spectators of her
labour, began to increase the opening, and drew out the dead body of a
queen scarcely come from its envelope of a nymph.
Meanwhile, the victorious young queen attacked another royal cell, but
did not endeavour to introduce her extremity into it. There was only a
royal nymph, and no queen, come to maturity, as in the first cell. In
all probability, nymphs of queens inspire their rivals with less
animosity; still they do not escape destruction: because, whenever a
royal cell has been opened before the proper time, the bees extract the
contents in whatever form they may be, whether worm, nymph, or queen.
Lastly, the young queen attacked the third cell, but could not succeed
in penetrating it. She laboured languidly, and appeared as if exhausted
by her first exertions. As we now required queens for some particular
experiments, we resolved to remove the other royal cells, yet in safety,
to secure them from her fury.
After this observation, we wished to see what ensued on two queens
leaving their cells at the same time, and in what manner one perished. I
find an observation on this head in my Journal, 15. May 1790.
In one of our thinnest hives, two queens left their cells almost at the
same moment. Whenever they observed each other, they rushed together,
apparently with great fury, and were in such a position that the antennæ
of each was seized by the teeth of the other: the head, breast, and
belly of the one were exposed to the head, breast, and belly of the
other: the extremity of their bodies were curved; they were reciprocally
pierced with the stings; and both fell dead at the same instant. But it
seems as if nature has not ordained that both combatants should perish
in the duel; but rather that, when finding themselves in the situation
described, namely, opposite, and belly to belly, they fly at that moment
with the utmost precipitation. Thus, when these two rivals felt the
extremities about to meet, they disengaged themselves, and each fled
away. You will observe, Sir, that I have repeated this observation very
often, so that it leaves no room for doubt: and I think that we may here
penetrate the intention of nature.
There ought to be none but one queen in a hive: therefore it is
necessary, if by chance a second is either produced or comes into the
hive, that one of the two must be destroyed. This cannot be committed to
the working bees, because, in a republic composed of so many
individuals, an equal consent cannot be supposed always to exist; it
might frequently happen that one group of bees destroyed one of the
queens, while a second would massacre the other; and the hive thus be
deprived of queens. Therefore it was necessary that the queens
themselves should be entrusted with the destruction of their rivals: but
as, in these combats, nature demands but a single victim, she has wisely
arranged that, at the moment when, from their position, the two
combatants might lose their lives, both feel so great an alarm, that
they think only of flight, and not of using their stings.
I am well aware of the hazard of error in minute researches into the
causes of the most trifling facts. But here the object and the means
seem so plain, that I have ventured to advance my conjectures. You will
judge better than I can, whether they are well founded.--Let me now
return from this digression.
A few minutes after the two queens separated, their terror ceased, and
they again began to seek each other. Immediately on coming in sight,
they rushed together, seized one another, and resumed exactly their
former position. The result of this encounter was the same. When their
bellies approached, they hastily disengaged themselves, and fled with
precipitation. During all this time, the workers seemed in great
agitation; and the tumult appeared to increase when the adversaries
separated. Two different times, we observed them stop the flight of the
queens, seize their limbs, and retain them prisoners above a minute. At
last, the queen, which was either the strongest or the most enraged,
darted on her rival at a moment when unperceived, and with her teeth
caught the origin of the wing; then rising above her, brought the
extremity of her own body under the belly of the other; and, by this
means, easily pierced her with the sting. Then she withdrew her sting
after losing hold of the wing. The vanquished queen fell down, dragged
herself languidly along, and, her strength failing, she soon expired.
This observation proved that virgin queens engage in single combats; but
we wished to discover whether those fecundated, and mothers, had the
same animosity.
On the 22. of July, we selected a flat hive, containing a very fertile
queen: and being curious to learn whether, as virgin queens, she would
destroy the royal cells, three were introduced into the middle of the
comb. Whenever she observed this, _she_ sprung forward on the whole, and
pierced them towards the bottom; nor did she desist until the included
nymphs were exposed. The workers which had hitherto been spectators of
this destruction, now came to carry the nymphs away. They greedily
devoured the food remaining at the bottom of the cells, and also sucked
the fluid from the abdomen of the nymphs: and then terminated with
destroying the cells from which they had been drawn.
In the next place, we introduced a very fertile queen into this hive;
after painting the thorax to distinguish her from the reigning queen. A
circle of bees quickly formed around the stranger, but their intention
was not to caress and receive her well; for they insensibly accumulated
so much, and surrounded her so closely, that in scarcely a minute she
lost her liberty and became a prisoner. It is a remarkable circumstance,
that other workers at the same time collected round the reigning queen
and restrained all her motions; we instantly saw her confined like the
stranger. Perhaps it may be said, the bees anticipated the combat in
which these queens were about to engage, and were impatient to behold
the issue of it, for they retained their prisoners only when they
appeared to withdraw from each other; and if one less restrained seemed
desirous of approaching her rival, all the bees forming the clusters
gave way to allow her full liberty for the attack; then if the queens
testified a disposition to fly, they returned to enclose them.
We have repeatedly witnessed this fact, but it presents so new and
singular a characteristic in the policy of bees, that it must be seen
again a thousand times before any positive assertion can be made on the
subject. I would therefore recommend that naturalists should attentively
examine the combat of queens, and particularly ascertain what part is
taken by the workers. Is their object to accelerate the combat? Do they
by any secret means excite the fury of the combatants? Whence does it
happen that accustomed to bestow every care on their queen, in certain
circumstances, they oppose her preparations to avoid impending danger?
A long series of observations are necessary to solve these problems. It
is an immense field for experiment, which will afford infinitely curious
results. I intreat you to pardon my frequent digressions. The subject is
deeply philosophical, genius such as your's is required to treat it
properly; and I shall now be satisfied with proceeding in the
description of the combat.
The cluster of bees that surrounded the reigning queen having allowed
her some freedom, she seemed to advance towards that part of the comb
where her rival stood; then, all the bees receded before her, the
multitude of workers, separating the two adversaries, gradually
dispersed, until only two remained; these also removed, and allowed the
queens to come in sight. At this moment, the reigning queen rushed on
the stranger, with her teeth seized her near the origin of the wing, and
succeeded in fixing her against the comb without any possibility of
motion or resistance. Next curving her body, she pierced this unhappy
victim of our curiosity with a mortal wound.
In the last place, to exhaust every combination, we had still to examine
whether a combat would ensue between two queens, one impregnated, and
the other a virgin; and what circumstances attended it.
On the 18. of September, we introduced a very fruitful queen into a
glass hive, already containing a virgin queen, and put her on the
opposite side of the comb, that we might have time to see how the
workers would receive her. She was immediately surrounded, but they
confined her only a moment. Being oppressed with the necessity of
laying, she dropped some eggs; however, we could not discover what
became of them; certainly the bees did not convey them to the cells,
for, on inspection, we found none there. The group surrounding this
queen having dispersed a little, she advanced towards the edge of the
comb, and soon approached very near the virgin queen. When in sight,
they rushed together; the virgin queen got on the back of the other, and
gave her several stings in the belly, but, having aimed at the scaly
part, they did not injure her, and the combatants separated. In a few
minutes, they returned to the charge; but this time the impregnated
queen mounted on her rival; however, she sought in vain to pierce her,
for the sting did not enter; the virgin queen then disengaged herself
and fled; she also succeeded in escaping another attack, where her
adversary had the advantage of position. These rivals appeared nearly of
equal strength; and it was difficult to foresee to which side victory
would incline, until at last, by a successful exertion, the virgin queen
mortally wounded the stranger, and she expired in a moment. The sting
had penetrated so far that the victorious queen was unable to extract
it, and she was overthrown by the fall of her enemy. She made great
exertions to disengage the sting: but could succeed by no other means
than turning on the extremity of the belly, as on a pivot. Probably the
barbs of the sting fell by this motion, and, closing like a spiral
around the stem, came more easily from the wound.
These observations, Sir, I think will satisfy you, respecting the
conjecture of our celebrated Reaumur. It is certain, that if several
queens are introduced into a hive, one alone will preserve the empire;
that the others will perish from her attacks; and that the workers will
at no time attempt to employ their stings against the stranger queen. I
can conceive what has misled M. Riems and Schirach; but it is necessary
for explaining it that I should relate a new feature in the policy of
bees, at considerable length.
In the natural state of hives, several queens from different royal
cells, may sometimes exist at the same moment, and they will remain
either until formation of a swarm or a combat among them decides to
which the throne shall appertain. But excepting this case, there never
can be supernumerary queens; and if an observer wishes to introduce one,
he can accomplish it only by force, that is by opening the hive. In a
word, no queen can insinuate herself into a hive in a natural state,
for the following reasons.
Bees preserve a sufficient guard, day and night, at the entrance of
their habitation. These vigilant centinels examine whatever is
presented; and, as if distrusting their eyes, they touch with the
antennæ every individual endeavouring to penetrate the hive, and also
the various substances put within their reach; which affords us an
opportunity of observing that the antennæ are certainly the organs of
feeling. If a stranger queen appears, she is instantly seized by the
bees on guard, which prevent her entry by laying hold of her legs or
wings with their teeth, and crowd so closely around her, that she cannot
move. Other bees, from the interior of the hive, gradually come to their
assistance, and confine her still more narrowly, all having their heads
towards the centre where the queen is inclosed; and they remain with
such evident anxiety, eagerness, and attention, that the cluster they
form may be carried about for some time, without their being sensible
of it. A stranger queen, so closely confined and hemmed in, cannot
possibly penetrate the hive. If the bees retain her too long imprisoned,
she perishes. Her death probably ensues from hunger, or the privation of
air; it is undoubted, at least, that she is never stung. We never saw
the bees direct their stings against her, except a single time, and then
it was owing to ourselves. We endeavoured, from compassion for a queen's
situation, to remove her from the center of a cluster; the bees became
enraged; and, in darting out their stings, some struck the queen, and
killed her. It is so certain that the stings were not purposely directed
against her, that several of the workers were themselves killed; and
surely they could not intend destroying one another. Had we not
interfered, they would have been content with confining the queen, and
would not have massacred her.
It was in similar circumstances that M. Riems saw the workers anxiously
pursue a queen. He thought they designed to sting her, and thence
concluded, that the office of the common bees is to kill supernumerary
queens. You have quoted his observations in the _Contemplation de la
Nature, part II, chap. 27, note 7_. But you are sensible, Sir, from
these details, that he has been mistaken. He did not know the attention
that bees bestow on what passes at the entrance of their hive, and he
was entirely ignorant of the means they take to prevent supernumerary
queens from penetrating it.
* * * * *
After ascertaining that the workers in no situation sting the
supernumerary queens, we were curious to learn how a stranger queen
would be received in a hive wanting a reigning one. To elucidate this
matter, we made numerous experiments, the detail of which would protract
this letter too much, therefore I shall relate only the principal
results.
Bees do not immediately observe the removal of their queen; their
labours are uninterrupted; they watch over the young, and perform all
their ordinary occupations. But, in a few hours, agitation ensues; all
appears a scene of tumult in the hive. A singular humming is heard; the
bees desert their young; and rush over the surface of the combs with a
delirious impetuosity. Then they discover their queen is no longer among
them. But how do they become sensible of it? How do the bees on the
surface of the comb discover that the queen is not on the next comb? In
treating of another characteristic of these animals, you have yourself,
Sir, proposed the same question; I am incapable of answering it indeed,
but I have collected some facts, that may perhaps facilitate the
elucidation of this mystery.