her belly was very slender, and she began to exhibit signs of agitation.
Her motion soon became more lively, yet she still continued examining
the cells as when about to lay; sometimes introducing half her belly,
but suddenly withdrawing it, without having laid. At other times she
deposited an egg, which lay in an irregular position, on one side of the
hexagon, and not fixed by an end to the bottom of the cell. The queen
produced no distinct sound in her course, and we heard nothing different
from the ordinary humming of bees. She passed over those in her way;
sometimes when she stopped, the bees meeting her also stopped; and
seemed to consider her. They advanced briskly, struck her with their
antennæ, and mounted on her back. She then went on carrying some of the
workers on her back. None gave her honey, but she voluntarily took it
from the cells in her way. The bees no longer inclosed and formed
regular circles around her. The first, aroused by her motions, followed
her running in the same manner, and in their passage excited those still
tranquil on the combs. The way the queen had traversed was evident after
she left it, by the agitation created, which was never afterwards
quelled: she had soon visited every part of the hive, and occasioned a
general agitation; if some places still remained tranquil, the bees in
agitation arrived, and communicated their motion. The queen no longer
deposited her eggs in cells; she let them fall fortuitously: nor did the
bees any longer watch over the young; they ran about in every different
direction; even those returning from the fields, before the agitation
came to its height, no sooner entered the hive than they participated in
these tumultuous motions. They neglected to free themselves of the waxen
pellets on their limbs, and ran blindly about. At last the whole rushed
precipitately towards the outlets of the hive, and the queen along with
them.
As it was of much consequence to see the formation of new swarms in this
hive, and, for that reason, as I wished it to continue very populous, I
removed the queen, at the moment she came out, that the bees might not
fly too far, and that they might return. In fact, after losing their
female, they did return to the hive. To increase the population still
more, I added another swarm, which had come from a straw hive on the
same morning, and removed its queen also.
All these facts were certain, and appeared susceptible of no error.
Notwithstanding this, I was particularly earnest to learn whether old
queens always followed the same course; which induced me, on the
twenty-ninth, to replace, in the glass hive, the queen a year old, which
had hitherto been the subject of my experiments, and had just began to
lay the eggs of males. On the same day, we found one of the royal cells
left by the preceding queen larger than the rest; and, from its length,
supposed the included worm two days old: the egg had, therefore, been
laid on the twenty-fourth by that queen, and the worm was hatched on the
twenty-seventh. On the thirtieth, the queen laid a great deal in the
large and small cells alternately. Now, and the two following days, the
bees enlarged several royal cells, but unequally, which proved that they
included larvæ of different ages. One was closed on the first of June,
and on the second another. The bees also commenced some new ones. All
was perfectly quiet at eleven in the morning; but, at mid-day, the
queen, from the utmost tranquillity, became evidently agitated; and her
agitation insensibly communicated to the workers in every part of their
dwelling. In a few minutes they precipitately crowded to the entrances,
and, along with the queen, left the hive. After they had settled on the
branch of a neighbouring tree, I sought for the queen; thinking that, by
removing her, the bees might return to the hive, which actually ensued.
Their first care seemed to consist in seeking the female; they were
still in great agitation, but gradually calmed; and in three hours
complete tranquillity was restored.
They had resumed their usual occupations on the third: they attended to
the young, worked within the open royal cells, and also watched on those
that were shut. They made a waved work on them, not by applying wax
cordons, but by removing wax from the surface. Towards the top this
waved work is almost imperceptible; it becomes deeper above, and the
workers excavate it still more from thence to the base of the pyramid.
The cell, when once shut, also becomes thinner; and is so much so,
immediately preceding the queen's metamorphosis from a nymph, that all
its motions are perceptible through the thin covering of wax on which
the waved work is founded. It is a very remarkable circumstance, that in
making the cells thinner, from the moment they are closed, the bees know
to regulate their labour so that it terminates only when the nymph is
ready to undergo its last metamorphosis.
On the seventh day the coccoon is almost completely _unwaxed_, if I may
use the expression, at the part next to the head and thorax of the
queen. This operation facilitates her exit; for she has nothing to do
but cut the silk that forms the coccoon. Most probably the object is, to
promote evaporation of the superabundant fluids of the nymph. I have
made some direct experiments to ascertain the fact, but they are yet
unfinished. A third royal cell was closed by the bees on the same day,
the third of June, twenty-four hours after closing the second. The like
was done to other royal cells successively, during the subsequent days.
Every moment of the seventh, we expected the queen to leave the royal
cell shut on the thirtieth of May. The seven days had elapsed. The
waving of her cell was so deep, that what passed within was pretty
perceptible; we could discern that the silk of the coccoon was cut
circularly, a line and a half from the extremity; but the bees being
unwilling that she should yet quit her cell, they had soldered the
covering to it with some particles of wax. What seemed most singular
was, that this female emitted a very distinct sound, or clacking from
her prison. It was still more audible in the evening, and even consisted
of several monotonous notes in rapid succession.
The same sound proceeded from the royal cell on the eighth. Several
bees kept guard round each royal cell.
The first cell opened on the ninth. The young queen was lively, slender,
and of a brown colour. Now, we understood why bees retain the female
captive in their cells, after the period for transformation has elapsed;
it is, that they may be able to fly the instant they are hatched. The
new queen occupied all our attention. When she approached the other
royal cells, the bees on guard pulled, bit her, and chased her away;
they seemed to be greatly irritated against her, and she enjoyed
tranquillity only when at a good distance from these cells. This
procedure was frequently repeated through the day. She twice emitted the
sound; in doing so she stood, her thorax against a comb, and the wings
crossed on her back; they were in motion but without being unfolded or
further opened. Whatever might be the cause of her assuming this
attitude, the bees were affected by it; all hung down their heads, and
remained motionless.
The hive presented the same appearances on the following day.
Twenty-three royal cells yet remained, assiduously guarded by a great
many bees. When the queen approached, all the guards became agitated,
surrounded her on all sides, bit, and commonly drove her away; sometimes
when in these circumstances, she emitted her sound, assuming the
position just described, from that moment the bees became motionless.
The queen confined in the second cell had not yet left it, and was heard
to hum several times. We accidentally discovered how the bees fed her.
On attentive examination, a small aperture was perceptible in the end of
the coccoon which she had cut to escape, and which her guards had again
covered with wax, to confine her still longer. She thrust her trunk
through the cleft; at first the bees did not observe it alternately
thrust out and drawn in, but one at length perceiving it, came to apply
its trunk to that of the captive queen, and then gave way to others that
also approached her with honey. When satisfied she retracted her trunk,
and the bees again closed up the opening with wax.
The queen this day between twelve and one became extremely agitated. The
royal cells had multiplied very much; she could go no where without
meeting them, and on approaching she was very roughly treated. Then she
fled, but to obtain no better reception. At last, these things agitated
the bees; they precipitately rushed through the outlets of the hive, and
settled on a tree in the garden. It singularly happened that the queen
was herself unable to follow or conduct the swarm. She had attempted to
pass between two royal cells before they were abandoned by the bees
guarding them, and she was so confined and maltreated as to be incapable
of moving. We then removed her into a separate hive prepared for a
particular experiment; the bees, which had clustered on a branch, soon
discovered their queen was not present, and returned of their own accord
to the hive. Such is an account of the second colony of this hive.
We were extremely solicitous to ascertain what would become of the other
royal cells. Four of the close ones had attained complete maturity, and
the queens would have left them had not the bees prevented it. They were
not open either previous to the agitation of the swarms, or at the
moment of swarming.
None of the queens were at liberty on the eleventh. The second should
have transformed on the eighth; thus she had been three days confined, a
longer period than the first which formed the swarm. We could not
discover what occasioned the difference in their captivity.
On the twelfth, the queen was at last liberated, as we found her in the
hive. She had been treated exactly as her predecessor; the bees allowed
her to rest in quiet, when distant from the royal cells, but tormented
her cruelly when she approached them. We watched this queen a long time,
but not aware that she would lead out a colony, we left the hive for a
few hours. Returning at mid-day, we were greatly surprised to find it
almost totally deserted. During our absence, it had thrown a prodigious
swarm, which still clustered on the branch of a neighbouring tree. We
also saw with astonishment the third cell open, and its top connected to
it as by a hinge. In all probability the captive queen, profiting by the
confusion that preceded the swarming, escaped. Thus, there was no doubt
of both queens being in the swarm. We found it so; and removed them,
that the bees might return to the hive, which they did very soon.
While we were occupied in this operation, the fourth captive queen left
her prison, and the bees found her on returning. At first they were very
much agitated, but calmed towards the evening, and resumed their wonted
labours. They formed a strict guard around the royal cells, and took
great care to remove the queen whenever she attempted to approach.
Eighteen royal cells now remained to be guarded.
The fifth queen left her cell at ten at night; therefore two queens were
now in the hive. They immediately began fighting, but came to disengage
themselves from each other. However they fought several times during the
night without any thing decisive. Next day, the thirteenth, we witnessed
the death of one, which fell by the wounds of her enemy. This duel was
quite similar to what is said of the combats of queens.
The victorious queen now presented a very singular spectacle. She
approached a royal cell, and took this moment to utter the sound, and
assume that posture, which strikes the bees motionless. For some
minutes, we conceived, that taking advantage of the dread exhibited by
the workers on guard, she would open it, and destroy the young female;
also she prepared to mount the cell; but in doing so she ceased the
sound, and quitted that attitude which paralyses the bees. The guardians
of the cell instantly took courage; and, by means of tormenting and
biting the queen, drove her away.
On the fourteenth, the sixth young queen appeared, and the hive threw a
swarm, with all the concomitant disorder before described. The agitation
was so considerable, that a sufficient number of bees did not remain to
guard the royal cells, and several of the imprisoned queens were thus
enabled to make their escape. Three were in the cluster formed by the
swarm, and other three remained in the hive. We removed those that had
led the colony, to force the bees to return. They entered the hive,
resumed their post around the royal cells, and maltreated the queens
when approaching.
A duel took place in the night of the fifteenth, in which one queen
fell. We found her dead next morning before the hive; but three still
remained, as one had been hatched during night. Next morning we saw a
duel. Both combatants were extremely agitated, either with the desire of
fighting, or the treatment of the bees, when they came near the royal
cells. Their agitation quickly communicated to the rest of the bees, and
at mid-day they departed impetuously with the two females. This was the
fifth swarm that had left the hive between the thirtieth of May and
fifteenth of June. On the sixteenth, a sixth swarm cast, which I shall
give you no account of, as it shewed nothing new.
Unfortunately we lost this, which was a very strong swarm; the bees flew
out of sight, and could never be found. The hive was now very thinly
inhabited. Only the few bees that had not participated in the general
agitation remained, and those that returned from the fields after the
swarm had departed. The cells were, therefore, slenderly guarded; the
queens escaped from them, and engaged in several combats, until the
throne remained with the most successful.
Notwithstanding the victories of this queen, she was treated with great
indifference from the sixteenth to the nineteenth, that is, the three
days that she preserved her virginity. At length, having gone to seek
the males, she returned with all the external signs of fecundation, and
was henceforth received with every mark of respect; she laid her first
eggs forty-six hours after fecundation.
Behold, Sir, a simple and faithful account of my observations on the
formation of swarms. That the narrative might be the more connected, I
have avoided interrupting it by the detail of several particular
experiments which I made at the same time for elucidating various
obscure points of their history. These shall be the subject of future
letters. For, although I have said so much, I hope still to interest
you.
_PREGNY, 6. September 1791._
_P. S._--In revising this letter, I find I have neglected taking notice
of an objection that may embarrass my readers, and which ought to be
answered.
After the first five swarms had thrown, I had always returned the bees
to the hive: it is not surprising, therefore, that it was continually so
sufficiently stocked that each colony was numerous. But things are
otherwise in the natural state: the bees composing a swarm do not return
to the hive; and it will undoubtedly be asked, What resource enables a
common hive to swarm three or four times without being too much
weakened?
I cannot lessen the difficulty. I have observed that the agitation,
which precedes the swarming, is often so considerable, that most of the
bees quit the hive, and in that case we cannot well comprehend how, in
three or four days afterwards, it can be in a state to send out another
colony equally strong.
But remark, in the first place, that the queen leaves a prodigious
quantity of workers' brood, which soon transforms to bees; and in this
way the population sometimes becomes almost as great after swarming as
before it.
Thus the hive is perfectly capable of affording a second colony without
being too much weakened. The third and fourth swarm weaken it more
sensibly; but the inhabitants always remain in sufficient numbers to
preserve the course of their labours uninterrupted; and the losses are
soon repaired by the great fecundity of the queen, as she lays above an
hundred eggs a day.
If, in some cases, the agitation of swarming is so great, that all the
bees participate in it, and leave the hive, the desertion lasts but for
a moment. The hive throws only during the finest part of the day, and it
is then that the bees are ranging through the country. Those that are
out, therefore, cannot share in the agitation; when returned to the
hive, they quietly resume their labours; and their number is not small,
for, when the weather is fine, at least a third of the bees are employed
in the fields at once.
Even in the most embarrassing case, namely, where the whole bees desert
the hive, it does not follow, that all those endeavouring to depart
become members of the new colony. When this agitation or delirium seizes
them, the whole rush forward and accumulate towards the entrance of the
hive, and are heated in such a manner that they perspire copiously.
Those near the bottom, and supporting the weight of all the rest, seem
drenched in perspiration; their wings grow moist; they are incapable of
flight; and even when able to escape, they advance no farther than the
board of the hive, and soon return.
Those that have lately left their cells remain behind the swarm, still
feeble, they could not support themselves in flight. Here then are also
many recruits to people what we should have thought a deserted
habitation.
LETTER X.
_THE SAME SUBJECT CONTINUED._
To preserve greater regularity in continuing the history of swarms, I
think it proper to recapitulate in a few words the principal points of
the preceding letter, and to expatiate on each, concerning the result of
new experiments, respecting which I have still been silent.
In the first place. _If at the return of spring, we examine a hive well
peopled, and governed by a fertile queen, we shall see her lay a
prodigious number of male eggs in the course of May, and the workers
will chuse that moment for constructing several royal cells of the kind
described by M. de Reaumur._ Such is the result of several long
continued observations, among which there has not been the slightest
variation, and I cannot hesitate in announcing it as demonstrated.
However, I should here add the necessary explanation. It is necessary
that the queen, before commencing her _great_ laying of the eggs of
males, be eleven months old; when young she lays only those of workers.
A queen, hatched in spring, will perhaps lay fifty or sixty eggs of
drones in whole, but before beginning her great laying of them, which
should be two thousand in a month, she must have completed her eleventh
month in age. In the course of our experiments, which more or less
disturbed the natural state of things, it often happened that the queen
did not attain this age until October, and immediately began laying male
eggs. The workers, as if induced by some emanation from the eggs, also
adopted this time for building the royal cells. No swarm resulted
thence, it is true, because in autumn all the necessary circumstances
are absolutely wanting, but it is not less evident, that there is a
secret relation between the production of the eggs of males, and the
construction of royal cells.
This laying commonly continues thirty days. The bees on the twentieth or
twenty-first lay the foundation of several royal cells. Sometimes they
build sixteen or twenty; we have even had twenty-seven. When the cells
are three or four lines high, the queen lays those eggs from which her
own species will come, but not the whole in one day. That the hive may
throw several swarms, it is essential that the young females conducting
them be not all produced at the same time. One may affirm, that the
queen anticipates the fact, for she takes care to allow at least the
interval of a day between every egg deposited in the cells. It is proved
by the bees knowing to close the cells the moment the worms are ready to
metamorphose to nymphs. Now, as they close all the royal cells at
different periods, it is evident the included worms are not all of an
equal age.
The queen's belly is very turgid before she begins laying the eggs of
drones; but it sensibly decreases as she advances, and when terminated
is very small. Thus she finds herself in a condition to undertake a
journey which circumstances may prolong; thus this condition was
necessary; and as every thing is harmonious in the laws of nature, the
origin of the males corresponds with that of the females, which they are
to fecundate.
Secondly. _When the larvæ hatched from the eggs laid by the queen, in
the royal cells, are ready to transform to nymphs, this queen leaves the
swarm conducting a swarm along with her; and the first swarm that
proceeds from the hive is uniformly conducted by the old queen._{M} I
think I can divine the reason of it.
That there may never be a plurality of females in a hive, nature has
inspired queens with a natural horror against each other; they never
meet without endeavouring to fight, and to accomplish their mutual
destruction. Thus, the chance of combat is equal between them, and
fortune will decide to which the empire shall pertain. But if one
combatant is older than the rest, she is stronger, and the advantage
will be with her. She will destroy her rivals successively as produced.
Thus, if the old queen did not leave the hive, when the young ones
undergo their last metamorphosis, it could produce no more swarms, and
the species would perish. Therefore, to preserve the species, it is
necessary that the old queen conduct the first swarm. But what is the
secret means employed by nature to induce her departure? I am ignorant
of it.
In this country it is very rare, though not without example, for the
swarm, led forth by the old queen, in three weeks to produce a new
colony, which is also conducted by the same old queen; and that may
happen thus. Nature has not willed that the queen shall quit the first
hive before her production of male eggs is finished. It is necessary for
her to be freed of them, that she may become lighter. Besides, if her
first occupation, on entering a new dwelling, was laying more male eggs,
still she might perish either from age or accident before depositing
those of workers. The bees in that case would have no means of replacing
her, and the colony would go to ruin.
All these things have been with infinite wisdom foreseen. The first
operation of the bees of a swarm is to construct the cells of workers.
They labour at them with great ardour, and as the ovaries of the queen
have been disposed with admirable foresight, the first eggs she has to
lay in her new abode are those of workers. Commonly her laying
continues ten or eleven days; and at this time portions of comb
containing large cells are fabricated. It may be affirmed, that the bees
know their queen will also lay the eggs of drones; she actually does
begin to deposit some, though in much smaller number than at first;
enough however to encourage the bees to construct royal cells. Now, if
in these circumstances the weather is favourable, it is not impossible
that a second colony may be formed, and that the queen may depart at the
head of it within three weeks of conducting the first swarm. But I
repeat, the fact is rare in our climate. Let me now return to the hives
from which the queen has led the first colony.
Thirdly. _After the old queen has conducted the first swarm from the
hive, the remaining bees take particular care of the royal cells, and
prevent the young queens successively hatched from leaving them, unless
at an interval of several days between each._