Part II
. chap. 22. note 1._ It would be necessary to seize the instant when the drone unites with the female. But how remote from the power of the observer are the means of ascertaining a copulation in the air. If you have satisfactory evidence that the fluid bedewing the last rings of the female is the same with that of the male, it is more than mere presumption in favour of copulation. Perhaps it may be necessary that the male should seize the female under the belly, which cannot easily be done but in the air. The large opening at the extremity of the queen, which you have observed in so particular a condition, seems to correspond to the singular size of the sexual parts of the male.
You wish, my dear Sir, that I should suggest some new experiments on these industrious republicans. In doing so, I shall take the greater pleasure and interest, as I know to what extent you possess the valuable art of combining ideas, and of deducing from this combination results adapted to the discovery of new facts. A few at this moment occur to me.
It may be proper to attempt the artificial fecundation of a virgin queen, by introducing a little of the male's prolific fluid with a pencil, and at the same time observing every precaution to avoid error. Artificial fecundation, you are aware, has already succeeded in more than one animal.
To ascertain that the queen, which has left the hive for impregnation, is the same that returns to deposit her eggs, you will find it necessary to paint the thorax with some varnish that resists humidity. It will also be right to paint the thorax of a considerable number of workers in order to discover the duration of their life. This is a more secure method than slight mutilations.
For hatching the worm, the egg must be fixed almost vertically by one end near the bottom of the cell. Is it true, that it is unproductive unless fixed in this manner? I cannot determine the fact; and therefore leave it to the decision of experiment.
I formerly mentioned to you that I had long doubted the real nature of the small ovular substances deposited by queens in the cells, and my inclination to suppose them minute worms not yet begun to expand. Their elongated figure seems to favour my suspicions. It would therefore be proper to watch them with the utmost assiduity, from the instant of production until the period of exclusion. If the integument bursts, there can be no doubt that these minute substances are real eggs.
I return to the mode of operating copulation. The height that the queen and the males rise to in the air prevent us from seeing what passes between them. On that account, the hive should be put into an apartment with a very lofty ceiling. M. de Reaumur's experiment of confining a queen with several males in a glass vessel, merits repetition; and if, instead of a vessel, a glass tube, some inches in diameter and several feet long, were used, perhaps something satisfactory might be discovered.
You have had the fortune to observe the small queens mentioned by the Abbe Needham, but which he never saw. It will be of great importance to dissect them for the purpose of finding their ovaries. When M. Reims informed me that he had confined three hundred workers, along with a comb containing no eggs, and afterwards found hundreds in it, I strongly recommended that he should dissect the workers. He did so; and informed me that eggs were found in three. Probably without being aware of it, he has dissected small queens. As small drones exist, it is not surprising if small queens are produced also, and undoubtedly by the same external causes.
It is of much consequence to be intimately acquainted with this species of queens, for they may have great influence on different experiments and embarrass the observer: we should ascertain whether they inhabit pyramidal cells smaller than the common, or hexagonal ones.
M. Schirach's famous experiment on the supposed conversion of a common worm into a royal one, cannot be too often repeated, though the Lusatian observers have already done it frequently. I could wish to learn whether, as the discoverer maintains, the experiment will succeed only with worms, three or four days old, and never with simple eggs.
The Lusatian observers, and those of the Palatinate, affirm, that when common bees are confined with combs absolutely void of eggs, they then lay none but the eggs of drones. Thus, there must be small queens producing the eggs of males only, for it is evident they must have produced those supposed to come from workers. But how is it possible to conceive that their ovaries contain male eggs alone?
According to M. de Reaumur, the life of chrysalids may be prolonged by keeping them in a cold situation, such as an ice-house. The same experiment should be made on the eggs of a queen; on the nymphs of drones and workers.
Another interesting experiment would be to take away all the combs composing the common cells, and leave none but those destined for the larvæ of males. By this means we should learn whether the eggs of common worms, laid by the queen in the large cells, will produce large workers. It is very probable, however, that deprivation of the common cells might discourage the bees, because they require them for their honey and wax. Nevertheless, it is likely, by taking away only part of the common cells, the workers may be forced to lay common eggs in the cells of drones.
I should also wish to have the young larvæ gently removed from the royal cell, and deposited at the bottom of a common one, along with some of the royal food.
As the figure of hives has much influence on the respective disposition of the combs, it would be a satisfactory experiment, greatly to diversify their shape and internal dimensions. Nothing could be better adopted to instruct us how bees can regulate their labours, and apply them to existing circumstances. This may enable us to discover
## particular facts which we cannot foresee.
The royal eggs and those producing drones, have not yet been carefully compared with the eggs from which workers come. But they ought to be so, that we may ascertain whether these different eggs have secret distinctive characteristics.
The food supplied by the workers to the royal worm, is not the same with that given to the common worm. Could we not endeavour, with the point of a pencil, to remove a little of the royal food, and give it to a common worm deposited in a cell of the largest dimensions? I have seen common cells hanging almost vertically, where the queen had laid; and these I should prefer for this experiment.
Various facts, which require corroboration, were collected in my Memoirs on Bees; of this number are my own observations. You can select what is proper, my dear Sir. You have already enriched the history of bees so much, that every thing may be expected from your understanding and perseverance. You know the sentiments with which you have inspired the CONTEMPLATOR OF NATURE. _Genthod, 18. August 1789._
FOOTNOTES:
{A} All these letters are addressed to the celebrated naturalist M. Bonnet.--_T._
{B} The leaf or book hive consists of twelve vertical frames or boxes, parallel to each other, and joined together. Fig. 1. the sides, f f. f g. should be twelve inches long, and the cross spars, f f. g g. nine or ten; the thickness of these spars an inch, and their breadth fifteen lines. It is necessary that this last measure should be accurate; a a. a piece of comb which guides the bees in their work; d. a moveable slider supporting the lower part; b b. pegs to keep the comb properly in the frame or box; four are in the opposite side; e e. pegs in the sides under the moveable slider to support it.
A book hive, consisting of twelve frames, all numbered, is represented fig. 2. Between 6 and 7 are two cases with lids, that divide the hive into two equal parts, and should only be used to separate the bees for forming an artificial swarm; a a. two frames which shut up the two sides of the hive, have sliders, b. b.
The entrance appears at the bottom of each frame. All should be close but 1 and 12. However it is necessary that they should open at pleasure.
The hive is partly open, fig. 3. and shews how the component parts may be united by hinges, and open as the leaves of a book. The two covers closing up the sides, a. a.
Fig. 4. is another view of fig. 1. a a. a piece of comb to guide the bees; b b. pegs disposed so as to retain the comb properly in the frame; c c. parts of two shelves; the one above is fixed, and keeps the comb in a vertical position; the under one, which is moveable, supports it below.
{C} I cannot insist that my readers, the better to comprehend what is here said, shall peruse the Memoirs of M. de Reaumur on Bees, and those of the Lusace Society; but I must request them to examine the extracts in M. Bonnet's works, tom. 5. 4to edit. and tom. 10. 8vo, where they will find a short and distinct abstract of all that naturalists have hitherto discovered on the subject.
{D} Vide M. Schirach's History of Bees, in a memoir by M. Hattorf, entitled, _Physical Researches whether the Queen Bee requires fecundation by Drones?_
{E} It will afterwards appear that what we took for the generative fluid, was the male organs of generation, left by copulation in the body of the female. This discovery we owe to a circumstance that shall immediately be related. Perhaps I should avoid prolixity, by suppressing all my first observations on the impregnation of the queen, and by passing directly to the experiments that prove she carries away the genital organs; but in such observations which are both new and delicate, and where it is so easy to be deceived, I think service is done to the reader by a candid avowal of my errors. This is an additional proof to so many others, of the absolute necessity that an observer should repeat all his experiments a thousand times, to obtain the certainty of seeing facts as they really exist.
LETTER II.
_SEQUEL OF OBSERVATIONS ON THE IMPREGNATION OF THE QUEEN BEE._
SIR,
All the experiments, related in my preceding letter, were made in 1787 and 1788. They seem to establish two facts, which had previously been the subject of vague conjecture: 1. The queen bee is not impregnated of herself, but is fecundated by copulation with the male. 2. Copulation is accomplished without the hive, and in the air.
The latter appeared so extraordinary, that notwithstanding all the evidence obtained of it, we eagerly desired to take the queen in the fact; but, as she always rises to a great height, we never could see what passed. On that account you advised us to cut part off the wings of virgin queens. We endeavoured to benefit by your advice, in every possible manner; but to our great regret, when the wings lost much, the bees could no longer fly; and, by cutting off only an inconsiderable portion, we did not diminish the rapidity of their flight. Probably there is a medium, but we were unable to attain it. On your suggestion, we tried to render their vision less acute, by covering the eyes with an opaque varnish, which was an experiment equally fruitless.
We likewise attempted artificial fecundation, and took every possible precaution to insure success. Yet the result was always unsatisfactory. Several queens were the victims of our curiosity; and those surviving remained sterile. Though these different experiments were unsuccessful, it was proved that queens leave their hives to seek the males, and that they return with undoubted evidence of fecundation. Satisfied with this, we could only trust to time or accident for decisive proof of an actual copulation. We were far from suspecting a most singular discovery, which we made in July this year, and which affords complete demonstration of the supposed event, namely, that the sexual organs of the male remain with the female.{F}
FOOTNOTES:
{F} The remainder of this Chapter chiefly consists of anatomical details. These may rather be considered an interruption of the narrative; and the Translator has judged it expedient to transfer them to an Appendix.
LETTER III.
_THE SAME SUBJECT CONTINUED.--OBSERVATIONS ON RETARDING THE FECUNDATION OF QUEENS._
In my first letter, I remarked, that when queens were prevented from receiving the approaches of the male until the twenty-fifth or thirtieth day of their existence, the result presented very interesting peculiarities. My experiments at that time were not sufficiently numerous; but they have since been so often repeated, and the result so uniform, that I no longer hesitate to announce, as a certain discovery, the singularities which retarded fecundation, produces on the ovaries of the queen. If she receives the male during the first fifteen days of her life, she remains capable of laying both the eggs of workers and of drones; but should fecundation be retarded until the twenty-second day, her ovaries are vitiated in such a manner that she becomes unfit for laying the eggs of workers, and will produce only those of drones.
In June 1787, being occupied in researches relative to the formation of swarms, I had occasion, for the first time, to observe a queen that laid none but the eggs of males. When a hive is ready to swarm, I had before observed, that the moment of swarming is always preceded by a very lively agitation, which first affects the queen, is then communicated to the workers, and excites such a tumult among them, that they abandon their labours, and rush in disorder to the outlets of the hive. I then knew very well the cause of the queen's agitation, and it is described in the history of swarms, but I was ignorant how the delirium communicated to the workers; and this difficulty interrupted my researches. I therefore thought of investigating, by direct experiments, whether at all times, when the queen was greatly agitated, even not in the time of the hive swarming, her agitation would in like manner be communicated to the workers. The moment a queen was hatched, I confined her to the hive by contracting the entrances. When assailed by the imperious desire of union with the males, I could not doubt that she would make great exertions to escape, and that the impossibility of it would produce a kind of delirium. I had the patience to observe this queen thirty-four days. Every morning about eleven o'clock, when the weather was fine and the sunshine invited the males to leave their hives, I saw her impetuously traverse every corner of her habitation, seeking to escape. Her fruitless efforts threw her into an uncommon agitation, the symptoms of which I shall elsewhere describe, and all the common bees were affected by it. As she never was out all this time, she could not be impregnated. At length, on the thirty-sixth day, I set her at liberty. She soon took advantage of it; and was not long of returning with the most evident marks of fecundation.
Satisfied with the particular object of this experiment, I was far from any hopes that it would lead to the knowledge of another very remarkable fact; how great was my astonishment, therefore, on finding that this female, which, as usual, began to lay forty-six hours after copulation, laid the eggs of drones, but none of workers, and that she continued ever afterwards to lay those of drones only.
At first, I exhausted myself with conjectures on this singular fact; the more I reflected on it, the more did it seem inexplicable. At length, by attentively meditating on the circumstances of the experiment it appeared there were two principles, the influence of which I should first of all endeavour to appreciate separately. On the one hand, this queen had suffered long confinement; on the other, her fecundation had been extremely retarded. You know, Sir, that queens generally receive the males about the fifth or sixth day, and this queen had not copulated until the thirty-sixth. Little weight could be given to the supposition, that the peculiarity could be occasioned by confinement. Queens, in the natural state, leave their hives only once to seek the males. All the rest of their life they remain voluntary prisoners. Thus, it was improbable that captivity could produce the effect I wished to explain. At the same time, as it was essential to neglect nothing in a subject so new, I wished to ascertain whether it was owing to the length of confinement, or to retarded fecundation.
Investigating this was no easy matter. To discover whether captivity, and not retarded fecundation, vitiated the ovaries, it was necessary to allow a female to receive the approaches of a male, and also to keep her imprisoned. Now this could not be, for bees never copulate in hives. On the same account, it was impossible to retard the copulation of a queen without keeping her in confinement. I was long embarrassed by the difficulty. At length, I contrived an apparatus, which, though imperfect, nearly fulfilled my purpose.
I put a queen, at the moment of her last metamorphosis, into a hive well stored, and sufficiently provided with workers and males; the entrance was contracted so as to prevent her exit, but allowed free passage to the workers. I also made another opening for the queen, and adapted a glass tube to it, communicating with a cubical glass box eight feet high. Hither the queen could at all times come and fly about, enjoying a purer air than was to be found within the hive; but she could not be fecundated; for though the males flew about within the same bounds, the space was too limited to admit of any union between them. By the experiments related in my first letter, copulation takes place high in the air only: therefore, in this apparatus, I found the advantage of retarding fecundation, while the liberty the queen now had, did not render her situation too remote from the natural state. I attended to the experiment fifteen days. Every fine morning, the young captive left her hive; she traversed her glass prison, and flew much about, and with great facility. She laid none during this interval, for she had not united with a male. On the sixteenth day, I set her at liberty: she left the hive, rose aloft in the air, and soon returned with full evidence of impregnation. In two days, she laid, first the eggs of workers, and afterwards as many as the most fertile queens.
It thence followed, 1. That captivity did not alter the organs of queens. 2. When fecundation took place within the first sixteen days, she produced both species of eggs.
This was an important experiment. It rendered my labours much more simple, by clearly pointing out the method to be pursued: it absolutely precluded the supposed influence of captivity; and left nothing for investigation but the consequences of retarded fecundation.
With this view, I repeated the experiment; but, instead of giving the virgin queen liberty on the sixteenth day, I retained her until the twenty-first. She departed, rose high in the air, was fecundated, and returned. Thirty-six hours afterwards, she began to lay: but it was the eggs of males only, and, although very fruitful afterwards, she laid no other kind.
I occupied myself the remainder of 1787, and the two subsequent years, with experiments on retarded fecundation, and had constantly the same results. It is undoubted, therefore, that when the copulation of queens is retarded beyond the twentieth day, only an imperfect impregnation is operated: instead of laying the eggs of workers and males equally, they will lay none but those of males.
I do not aspire to the honour of explaining this singular fact. When the course of my experiments led me to observe that some queens laid only the eggs of drones, it was natural to investigate the proximate cause of such a singularity; and I ascertained that it arose from retarded fecundation. My evidence is demonstrative, for I can always prevent queens from laying the eggs of workers, by retarding their fecundation until the twenty-second or twenty-third day. But, what is the remote cause of this peculiarity; or, in other words, why does the delay of impregnation render queens incapable of laying the eggs of workers? This is a problem on which analogy throws no light: nor in all physiology am I acquainted with any fact that bears the smallest similarity.
The problem becomes still more difficult by reflecting on the natural state of things, that is when fecundation has not been delayed. The queen then lays the eggs of workers forty-six hours after copulation, and continues for the subsequent eleven months to lay these alone: and it is only after this period that a considerable and uninterrupted laying of the eggs of drones commences. When, on the contrary, impregnation is retarded after the twentieth day, the queen begins, from the forty-sixth hour, to lay the eggs of males, and no other kind during her whole life. As, in the natural state, she lays the eggs of workers only, during the first eleven months, it is clear that these, and the male eggs, are not indiscriminately mixed in the oviducts. Undoubtedly they occupy a situation corresponding to the principles that regulate laying: the eggs of workers are first, and those of drones behind them. Farther, it appears that the queen can lay no male eggs until those of workers, occupying the first place in the oviducts, are discharged. Why, then, is this order inverted by retarded copulation? How does it happen that all the workers eggs which the queen ought to lay, if fecundation was in due time, now wither and disappear, yet do not, impede the passage of the eggs of drones, which occupy only the second place in the ovaries. Nor is this all. I have satisfied myself that a single copulation is sufficient to impregnate the whole eggs that a queen will lay in the course of at least two years. I have even reason to think, that a single copulation will impregnate all the eggs that she will lay during her whole life: but I want absolute proof for more than two years. This, which is truly a very singular fact in itself, renders the influence of retarded fecundation still more difficult to be accounted for. Since a single copulation suffices, it is clear that the male fluid acts from the first moment on all the eggs that the queen will lay in two years. It gives them, according to your principles, that degree of _animation_ that afterwards effects their successive expansion. Having received the first impressions of life, they grow, they mature, so to speak, until the day they are laid: and as the laws of laying are constant, because the eggs of the first eleven months are always those of workers, it is evident that those which appear first are also the eggs that come soonest to maturity. Thus, in the natural state, the space of eleven months is necessary for the male eggs to acquire that degree of increment they must have attained when laid. This consequence, which to me seems immediate, renders the problem insoluble. How can the eggs, which should grow slowly for eleven months, suddenly acquire their full expansion in forty-eight hours, when fecundation has been retarded twenty-one days, and by the effect of this retardation alone? Observe, I beseech you, that the hypothesis of successive expansion is not gratuitous; it rests on the principles of sound philosophy. Besides, for conviction that it is well founded, we have only to look at the figures given by Swammerdam of the ovaries of the queen bee. There we see eggs in that part of the oviducts contiguous to the vulva, much farther advanced, and larger than those contained in the opposite part. Therefore the difficulty remains in full force: it is an abyss where I am lost.
The only known fact bearing any relation to that now described, is the state of certain vegetable seeds, which, although extremely well preserved, lose the faculty of germination from age. The eggs of workers may also preserve, only for a very short time, the property of being fecundated by the seminal fluid; and, after this period, which is about fifteen or eighteen days, become disorganised to that degree, that they can no longer be animated by it. I am sensible that the comparison is very imperfect; besides, it explains nothing, nor does it even put us on the way of making any new experiments. I shall add but one reflection more.
Hitherto no other effect has been observed from the retarded impregnation of animals, but that of rendering them absolutely sterile. The first instance of a female still preserving the faculty of engendering males, is presented by the queen bee. But as no fact in nature is unique, it is most probable that the same peculiarity will also be found in other animals. An extremely curious object of research would be to consider insects in this new point of view, I say _insects_, for I do not conceive that any thing analogous will be found in other species of animals. The experiments now suggested would necessarily begin with insects the most analogous to bees; as wasps, humble bees, mason bees, all species of flies, and the like. Some experiments might also be made on butterflies; and, perhaps, an animal might be found whose retarded fecundation would be attended with the same effects as that of queen bees. Should the animal be larger, dissection will be more easily accomplished; and we may discover what happens to the eggs when retarded fecundation prevents their expansion. At least, we might hope that some fortunate circumstance would lead to solution of the problem{G}.
Let us now return to my experiments. In May 1789, I took two queens just when they had undergone the last metamorphosis: one was put in a _leaf hive_, well provided with honey and wax, and sufficiently inhabited by workers and males. The other was put into a hive exactly similar, from which all the drones were removed. The entrances of these hives were too confined for the passage of the females and drones, but the common bees enjoyed perfect liberty. The queens were imprisoned thirty days; and being then set at liberty, they departed, and returned impregnated. Visiting the hives in the beginning of July, I found much brood, but wholly consisting of the worms and nymphs of males. There actually was not a single worker's worm or nymph. Both queens laid uninterruptedly until autumn, and constantly the eggs of drones. Their laying ended in the first week of November, as that of my other queens.
I was very earnest to learn what would become of them in the subsequent spring, whether they would resume laying, or if new fecundation would be necessary; and if they did lay, of what species the eggs would be. However, the hives being very weak, I dreaded they might perish during winter. Fortunately, we were able to preserve them; and from April 1790, they recommenced laying. The precautions we had taken prevented them from receiving any new approaches of the male. Their eggs were still those of males.
It would have been extremely interesting to have followed the history of these two females still farther, but, to my great regret, the workers abandoned their hives on the fourth of May, and that same day I found both queens dead. No weevils were in the hive, which could disturb the bees; and the honey was still very plentiful: but as no workers had been been produced in the course of the preceding year, and winter had destroyed many, they were too few in spring to engage in their wonted labours, and, from discouragement, deserted their habitation to occupy the neighbouring hives.
In my Journal, I find a detail of many experiments on the retarded impregnation of queen bees, so many, that transcribing the whole would be tedious. I may repeat, however, that there was not the least variation in the principle, and that whenever the copulation of queens was postponed beyond the twenty-first day, the eggs of males only were produced. Therefore, I shall limit my narrative to those experiments that have taught me some remarkable facts.
A queen being hatched on the fourth of October 1789, we put her into a leaf-hive. Though the season was well advanced, a considerable number of males was still in the hive; and it here became important to learn, whether, at this period of the year, they could equally effect fecundation; also, in case it succeeded, whether a laying, begun in the middle of autumn, would be interrupted or continued during winter. Thus, we allowed the queen to leave the hive. She departed, indeed, but made four and twenty fruitless attempts before returning with the evidence of fecundation. Finally, on the thirty-first of October, she was more fortunate: She departed, and returned with the most undoubted proof of the success of her amours: She was now twenty-seven days old, consequently fecundation had been retarded. She ought to have begun laying within forty-six hours, but the weather was cold, and she did not lay; which proves, as we may cursorily remark, that refrigeration of the atmosphere is the principal agent that suspends the laying of queens during winter. I was excessively impatient to learn whether, on the return of spring, she would prove fertile, without a new copulation. The means of ascertaining the fact was easy; for the entrances of the hives only required contraction, so as to prevent her from escaping. She was confined from the end of October until May. In the middle of March, we visited the combs, and found a considerable number of eggs, but, none being yet hatched, we could not know whether they would produce workers or males. On the fourth of April, having again examined the state of the hive, we found a prodigious quantity of nymphs and worms, all of drones; nor had this queen laid a single worker's egg.
Here, as well as in the preceding experiment, retardation had rendered the queens incapable of laying the eggs of workers. But this result is the more remarkable, as the queen did not commence laying until four months and a half after fecundation. It is not rigorously true, therefore, that the term of forty-six hours elapses between the copulation of the female and her laying; the interval may be much longer, if the weather grows cold. Lastly, it follows, that although cold will retard the laying of a queen impregnated in autumn, she will begin to lay in spring without requiring new copulation.
It may be added, that the fecundity of the queen, whose history is given here, was astonishing. On the first of May, we found in her hive, besides six hundred males, already flies, two thousand four hundred and thirty-eight cells, containing either eggs or nymphs of drones. Thus, she had laid more than three thousand male eggs during March and April, which is above fifty each day. Her death soon afterwards unfortunately interrupted my observation, I intended to calculate the total number of male eggs that she should lay throughout the year, and compare it with those of queens whose fecundation had not been retarded. You know, Sir, that the latter lay about two thousand male eggs in spring; and another laying, but less considerable, commences in August, also in the interval, that they produce the eggs of workers almost solely. But it is otherwise with the females whose copulation has been retarded: they produce no workers' eggs. For four or five months following, they lay the eggs of males without interruption, and in such numbers, that, in this short time, I suppose one queen gives birth to more drones than a female, whose fecundation has not been retarded, produces in the course of two years. It gives me much regret, that I have not been able to verify this conjecture.
I should also describe the very remarkable manner in which queens, that lay only the eggs of drones, sometimes deposit them in the cells. Instead of being placed in the lozenges forming the bottom, they are frequently deposited on the lower side of the cells, two lines from the mouth. This arises from the body of such queens being shorter than that of those whose fecundation has not been retarded. The extremity remains slender, while the first two rings next the thorax are uncommonly swoln. Thus, in disposing themselves for laying, the extremity cannot reach the bottom of the cells on account of the swoln rings; consequently the eggs must remain attached to the part that the extremity reaches. The worms proceeding from them pass their vermicular state in the same place where the eggs were deposited, which proves that bees are not charged with the care of transporting the eggs as has been supposed. But here they follow another plan. They extend beyond the surface of the comb those cells where they observe the eggs deposited, two lines from the mouth.
Permit me, Sir, to digress a moment from the subject, to give the result of an experiment which seems interesting. Bees, I say, are not charged with the care of transporting into cells, the eggs misplaced by the queen: and, judging by the single instance I have related, you will think me well entitled to deny this feature of their industry. However, as several authors have maintained the reverse, and even demanded our admiration of them in conveying the eggs, I should explain clearly that they are deceived.
I had a glass hive constructed of two stages; the higher was filled with combs of large cells, and the lower with those of common ones. A kind of division, or diaphraghm, separated these two stages from each other, having at each side an opening for the passage of the workers from one stage to the other, but too narrow for the queen. I put a considerable number of bees into this hive; and, in the upper part, confined a very fertile queen that had just finished her great laying of male eggs; therefore she had only those of workers to lay, and she was obliged to deposit them in the surrounding large cells from the want of others. My object in this arrangement will already be anticipated. My reasoning was simple. If the queen laid workers' eggs in the large cells, and the bees were charged with transporting them if misplaced, they would infallibly take advantage of the liberty allowed to pass from either stage: they would seek the eggs deposited in the large cells, and carry them down to the lower stage containing the cells adapted for that species. If, on the contrary, they left the common eggs in the large cells, I should obtain certain proof that they had not the charge of transporting them.
The result of this experiment excited my curiosity extremely. We observed the queen several days without intermission. During the first twenty-four hours, she persisted in not laying a single egg in the surrounding cells; she examined them one after another, but passed on without insinuating her belly into one. She was restless, and traversed the combs in all directions: her eggs appeared an oppressive burden, but she persisted in retaining them rather than they should be deposited in cells of unsuitable diameter. The bees, however, did not cease to pay her homage, and treat her as a mother. I was amused to observe, when she approached the edges of the division separating the two stages, that she gnawed at them to enlarge the passage: the workers approached her, and also laboured with their teeth, and made every exertion to enlarge the entrance to her prison, but ineffectually. On the second day, the queen could no longer retain her eggs: they escaped in spite of her, and fell at random. Then we conceived that the bees would convey them into the small cells of the lower stage, and we sought them there with the utmost assiduity; but I can safely affirm there was not one. The eggs that the queen still laid the third day disappeared as the first. We again sought them in the small cells, but none were there. The fact is, they are ate by the workers; and this is what has deceived the naturalists, who supposed them carried away. They have observed the misplaced eggs disappear, and, without farther investigation, have asserted that the bees convey them elsewhere: they take them, indeed, not to convey them any where, but to devour them. Thus nature has not charged bees with the care of placing the eggs in the cells appropriated for them, but she has inspired females themselves with sufficient instinct to know the species of eggs they are about to lay, and to deposit them in suitable cells. This has already been observed by M. de Reaumur, and here my observations correspond with his. Thus it is certain that in the natural state, when fecundation takes place at the proper time, and the queen has suffered from nothing, she is never deceived in the choice of the cells where her eggs are to be deposited; she never fails to lay those of workers in small cells, and those of males in large ones. The distinction is important, for the same certainty of instinct is no longer conspicuous in the conduct of those females whose impregnation has been deferred. I was oftener than once deceived respecting the eggs that such queens laid, for they were deposited indiscriminately in small cells and those of drones; and not aware of their instinct having suffered, I conceived that the eggs in small cells would produce workers; therefore I was very much surprised, when, at the moment they should have been hatched, the bees closed up the cells, and demonstrated, by anticipation, that the included worms would change into drones; they actually became males; those produced in small cells were small, those in large cells large. Thus I must warn observers, who would repeat my experiments on queens that 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 been the cause of vitiation. He justly felicitated himself on discovering a method to prevent the destruction of hives in this situation, which was simple, for it consisted in removing the queen that laid the eggs of males only, and substituting one for her whose ovaries were not impaired. But to make the substitution effectual, it was necessary to procure queens at pleasure; a secret reserved for M. Schirach, and of which I shall speak in the following letter. You observe that the whole experiments of the German naturalist tended to the preservation of the hives whose queens laid none except male eggs; and that he did not attempt to discover the cause of the vice evident in their ovaries.
M. de Reaumur also says a few words, somewhere, of a hive containing many more drones than workers, but advances no conjectures on the cause. However, he adds, as a remarkable circumstance, that the males were tolerated in this hive until the subsequent spring. It is true that bees governed by a queen laying only male eggs, or by a virgin queen, preserve their drones several months after they have been massacred in other hives. I can ascribe no reason for it, but it is a fact I have several times witnessed during my long course of observations on retarded impregnation. In general it has appeared that while the queen lays male eggs, bees do not massacre the males already perfect in the hive. PREGNY, _21. August 1791_.
FOOTNOTES:
{G} The experiments suggested in this paragraph, recall a singular reflection of M. de Reaumur. Where treating of oviparous flies, he says, it would not be impossible for a hen to produce a living chicken, if, after fecundation, the eggs she should first lay could by any means be retained twenty-one days in the oviducts. _Mem. sur. les Insect. tom. 4. mem. 10._
LETTER IV.
_ON M. SCHIRACH'S DISCOVERY._
When you found it necessary, Sir, in the new edition of your works, to give an account of M. Schirach's beautiful experiments on the conversion of common worms into royal ones, you invited naturalists to repeat them. Indeed such an important discovery required the confirmation of several testimonies. For this reason, I hasten to inform you that all my researches establish the reality of the discovery. During ten years that I have studied bees, I have repeated M. Schirach's experiment so often, and with such uniform success, that I can no longer have the least doubt on the subject. Therefore, I consider it an established fact, when bees lose their queen, and several workers' worms are preserved in the hive, they enlarge some of their cells, and supply them not only with a different kind of food, but a greater quantity of it, and the worms reared in this manner, instead of changing to common bees, become real queens. I request my readers to reflect on the explanation you have given of so uncommon a fact, and the philosophical consequences you have deduced from it. _Contemplation de la Nature, part. II, chap. 27._
In this letter I shall content myself with some account of the figure of the royal cells constructed by bees around those worms that are destined for the royal state, and terminate with discussing some points wherein my observations differ from those of M. Schirach.
Bees soon become sensible of having lost their queen, and in a few hours commence the labour necessary to repair their loss. First, they select the young common worms, which the requisite treatment is to convert into queens, and immediately begin with enlarging the cells where they are deposited. Their mode of proceeding is curious; and the better to illustrate it, I shall describe the labour bestowed on a single cell, which will apply to all the rest, containing worms destined for queens. Having chosen a worm, they sacrifice three of the contiguous cells: next, they supply it with food, and raise a cylindrical inclosure around, by which the cell becomes a perfect tube, with a rhomboidal bottom; for the parts forming the bottom are left untouched. If the bees damaged it, they would lay open three corresponding cells on the opposite surface of the comb, and, consequently, destroy their worms, which would be an unnecessary sacrifice, and Nature has opposed it. Therefore, leaving the bottom rhomboidal, they are satisfied with raising a cylindrical tube around the worm, which, like the other cells in the comb, is horizontal. But this habitation remains suitable to the worm called to the royal state only during the first three days of its existence: another situation is requisite for the other two days it is a worm. Then, which is so small a portion of its life, it must inhabit a cell nearly of a pyramidal figure, and hanging perpendicularly; we may say the workers know it; for, after the worm has completed the third day, they prepare the place to be occupied by its new lodging. They gnaw away the cells surrounding the cylindrical tube, mercilessly sacrifice their worms, and use the wax in constructing a new pyramidal tube, which they solder at right angles to the first, and work it downwards. The diameter of this pyramid decreases insensibly from the base, which is very wide, to the point. During the two days that it is inhabited by the worm, a bee constantly keeps its head more or less inserted into the cell, and, when this worker quits it, another comes to occupy its place. In proportion as the worm grows, the bees labour in extending the cell, and bring food, which they place before its mouth, and around its body, forming a kind of cord around it. The worm, which can move only in a spiral direction, turns incessantly to take the food before its head: it insensibly descends, and at length arrives at the orifice of the cell. Now is the time of transformation to a nymph. As any farther care is unnecessary, the bees close the cell with a peculiar substance appropriated for it, and there the worm undergoes both its metamorphoses.
Though M. Schirach supposes that none but worms three days old are selected for the royal treatment, I am certain of the contrary; and that the operation succeeds equally well on those of two days only. I must be permitted to relate at length the evidence I have of the fact, which will both demonstrate the reality of common worms being converted into queens, and the little influence which their age has on the effect of the operation.
I put some pieces of comb, with some workers eggs, in the cells, and of the same kind as those already hatched, into a hive deprived of the queen. The same day several cells were enlarged by the bees, and converted into royal cells, and the worms supplied with a thick bed of jelly. Five were then removed from those cells, and five common worms, which, forty-eight hours before we had seen come from the egg substituted for them. The bees did not seem aware of the change; they watched over the new worms the same as over those chosen by themselves; they continued enlarging the cells, and closed them at the usual time. When they had hatched on them seven days{H}, we removed the cells to see the queens that were to be produced. Two were excluded, almost at the same moment, of the largest size, and well formed in every respect. The term of the other cells having elapsed, and no queen appearing, we opened them. In one, was a dead queen, but still a nymph; the other two were empty. The worms had spun their silk coccoons, but died before passing into their nymphine state, and presented only a dry skin. I can conceive nothing more conclusive than this experiment. It demonstrates that bees have the power of converting the worms of workers into queens; since they succeeded in procuring queens, by operating on the worms which we ourselves had selected. It is equally demonstrated, that the success of the operation does not depend on the worms being three days old, as those entrusted to the bees were only two. Nor is this all; bees can convert worms still younger into queens. The following experiment showed, that when the queen is lost, they destine worms only a few hours old to replace her.
I was in possession of a hive, which being long deprived of the female, had neither egg nor worm. I provided a queen of the greatest fertility; and she immediately began laying in the cells of workers. I removed this female before being quite three days in the hive, and before any of her eggs were hatched. The following morning, that is, the fourth day, we counted fifty minute worms, the oldest scarcely hatched twenty-four hours. However, several were already destined for queens, which was proved by the bees depositing around them a much more abundant provision of food than is supplied to common worms. Next day, the worms were near forty hours old: the bees had enlarged and converted their hexagonal cells into cylindrical ones of the greatest capacity. During the subsequent days, they still laboured at them, and closed them on the fifth from the origin of the worms. Seven days after sealing of the first of these royal cells, a queen of the largest size proceeded from it. She immediately rushed towards the other royal cells, and endeavoured to destroy their nymphs and worms. In another letter, I shall recount the effects of her fury.
From these details, you will observe, Sir, that M. Schirach's experiments had not been sufficiently diversified when he affirmed that it was essential for the conversion of common worms into queens, they should be three days old. It is undoubted, that equal success attends the experiment not only with worms two days old, but also when they have been only a few hours in existence.
After my researches to corroborate M. Schirach's discovery, I was desirous of learning whether, as this observer conceives, the only means which the bees have of procuring a queen, is giving the common worms a certain kind of aliment, and rearing them in the largest cells. You will remember, that M. de Reaumur's sentiments are very different: "The mother should lay, and she does lay, eggs from which flies fit for being mothers must in their turn proceed. She does so; and it is evident the workers know what she is to do. Bees, to which the mother is so precious, seem to take a peculiar interest in the eggs that one is to proceed from, and to consider them of the greatest value. They construct
## particular cells where they are to be deposited.--The figure of a royal
cell only begun, very much resembles a cup, or, more correctly speaking, the cup that has lost its acorn."
M. de Reaumur, though he did not suspect the possibility of a common worm being converted into a queen, conceived that the queen bee laid a
## particular species of eggs in the royal cells, from which worms should
come that would be queens. According to M. Schirach, on the other hand, bees always having the power of procuring a queen by bringing up worms three days old in a particular manner, it would be needless for nature to grant females the faculty of laying royal eggs. Such prodigality is, in his eyes, inconsistent with the ordinary laws of nature. Therefore he maintains, in direct terms, that she does not lay royal eggs in cells purposely prepared to receive them. He considers the royal cells only as common ones, enlarged by the bees at the moment when the included worm is destined for a queen; and adds, that the royal cell would always be too long for the belly of the mother to reach the bottom.
I admit that M. de Reaumur no where says he has seen the queen lay in the royal cell. However he did not doubt the fact; and, after all my observations, I must esteem his opinion just. It is quite certain that, at particular periods of the year, the bees prepare royal cells; that the females deposit their eggs in them; and that worms, which shall became queens, proceed from these eggs.
M. Schirach's objection, concerning the length of the cells, proves nothing; for the queen does not delay depositing her egg till they are finished. While only sketched and shaped like the cup of an acorn, she lays it. This naturalist, dazzled by the brilliancy of his discovery, saw only part of the truth. He was the first to find out the resource granted to bees by nature, for repairing the loss of their queen; and too soon persuaded himself that she had provided no other resource for the production of females. This error arose from not observing bees in very flat hives: had he used such as mine, he would have found, on opening them in spring, a confirmation of M. de Reaumur's opinion. Then, which is the season of swarming, hives in good condition are governed by a very fruitful queen: there are royal cells of a figure widely different from those constructed around the worms destined by the bees for queens. They are large, attached to the comb by a stalk, and hanging vertically like stalactites, such, in short, as M. de Reaumur has described them. The females lay in them before completion. We have surprised a queen depositing the egg when the cell was only as the cup of an acorn. The workers never lengthen them until the egg has been laid. In proportion as the worm grows, they are enlarged, and closed by the bees when the first transformation approaches. Thus it is true, that, in spring, the queen deposits in royal cells, previously prepared, eggs from which flies of her own species are to come. Nature has, therefore, provided a double means for the multiplication and conservation of their race.
_PREGNY, 24. August 1791._
FOOTNOTES:
{H} The author's meaning here is obscure.--T.
LETTER V.
_EXPERIMENTS PROVING THAT THERE ARE SOMETIMES COMMON BEES WHICH LAY FERTILE EGGS._
The singular discovery of M. Riems, concerning the existence of fertile workers, has appeared very doubtful to you, Sir. You have suspected that the eggs ascribed to workers by this naturalist had actually been produced by small queens, which, on account of their size, were confounded with common bees. But you do not positively insist that M. Riems is deceived; and, in the letter which you did me the honour to address to me, you requested me to investigate, by new experiments, whether there are actually working bees capable of laying fertile eggs. I have made these experiments with great care: and it is for you to judge of the confidence they merit.
On the fifth of August 1788, we found the eggs and worms of large drones in two hives, which had both been some time deprived of queens. We also observed the rudiments of some royal cells appended like stalactites to the edges of the combs. The eggs of males were in them. Being perfectly secure that there was no queen of large size among the bees of these two hives, the eggs, which daily became more numerous, were evidently laid either by queens of small size or by fertile workers. I had reason to believe it was actually by common bees, for we had frequently observed them inserting the posterior part into the cells; and assuming the same attitude as the queen when laying. But, not withstanding every exertion, we had never been able to seize one in this situation, to examine it more narrowly. And we were unwilling to assert any thing positively, without having the bees in our hands that had actually laid. Therefore our observations were continued with equal assiduity, in hopes that, by some fortunate chance, or in a moment of address, we could secure one of them. More than a month all our endeavours were abortive.
My assistant then offered to perform an operation that required both courage and patience, and which I could not resolve to suggest, though the same expedient had occurred to myself. He proposed to examine each bee in the hive separately, to discover whether some small queen had not insinuated herself among them, and escaped our first researches. This was an important experiment; for, should no small queen be found, it would be demonstrative evidence that the eggs had been laid by simple workers.
To perform this operation with all possible exactness, immersing the bees was not enough. You know, Sir, that the contact of water stiffens their organs, that it produces a certain alteration of their external figure: and, from the resemblance of small queens to workers, the slightest alteration of shape would prevent us from distinguishing with sufficient accuracy to what species those immersed might belong. Therefore it was necessary to seize the whole bees of both hives, notwithstanding their irritation, and examine their specific character with the utmost care. This my assistant undertook, and executed with great address. Eleven days were employed in it; and, during all that time, he scarcely allowed himself any relaxation, but what the relief of his eyes required. He took every bee in his hand; he attentively examined the trunk, the hind limbs, and the sting: there was not one without the characteristics of the common bee, that is, the little basket on the hind legs, the long trunk, and the straight sting. He had previously prepared glass cases containing combs. Into these, he put each bee after examination. It is superfluous to observe they were confined, which was a precaution indispensible until termination of the experiment. Neither was it enough to establish that the whole were workers; we had also to continue the experiment, and observe whether any would produce eggs. Thus we examined the cells for several days, and soon observed new laid eggs, from which the worms of drones came at the proper time. My assistant held in his hands the bees that produced them; and as he was perfectly certain they were common ones, it is proved that there are sometimes fertile workers in hives.
Having ascertained M. Schirach's discovery, by so decisive an experiment, we replaced all the bees examined, in very thin glass hives, being only eighteen lines thick, and capable of containing but a single row of combs, and thus were extremely favourable to the observer. We thought, by strictly persisting to watch the bees, we might surprise a fertile one in the act of laying, seize and dissect her. This we were desirous of doing, for the purpose of comparing her ovaries with those of queens, and to ascertain the difference. At length, on the eighth of September, we had the good fortune to succeed.
A bee appeared in the position of a female laying. Before she had time to leave the cell, we suddenly opened the hive and seized her. She presented all the external characteristics of common bees; the only difference we could recognise, and that was a very slight one, consisted in the belly seeming less and more slender than that of workers. On dissection, her ovaries were found more fragile, smaller and composed of fewer oviducts than the ovaries of queens. The filaments containing the eggs were extremely fine, and exhibited swellings at equal distances. We counted eleven eggs of sensible size, some of which appeared ripe for laying. This ovary was double like that of queens.
On the ninth of September, we seized another fertile worker the instant she laid, and dissected her. The ovary was still less expanded than that of the preceding bee, and only four eggs had attained maturity. My assistant extracted one from the oviducts, and succeeded in fixing it by an end on a glass slider. We may take this opportunity of remarking, that it is in the oviducts themselves the eggs are imbued with the viscous liquid, with which they are produced, and not in passing through the spherical sac as Swammerdam believed. During the remainder of this month, we found ten fertile workers in the same hives, and dissected them all. In most, the ovaries were easily distinguished, but in some we could not discern the faintest traces of them. In these last, the oviducts to all appearance were but imperfectly developed, and more address than we had acquired in dissection was necessary to distinguish them.
Fertile workers never lay the eggs of common bees; they produce none but those of males. M. Riems had already observed this singular fact; and here all my observations correspond with his. I shall only add to what he says, that fertile workers are not absolutely indifferent in the choice of cells for depositing their eggs. They always prefer large ones; and only use small cells when unable to find those of larger diameter. But they so far correspond with queens whose impregnation has been retarded, that they sometimes lay in royal cells.
Speaking of females laying male eggs alone, I have already expressed my surprise that bees bestow, on those deposited in royal cells, such care and attention as to feed the worms proceeding from them, and, at the period of transformation, to close them up. But I know not, Sir, why I omitted to observe that, after sealing the royal cells, the workers build them up, and sit on them until the last metamorphosis of the included male{I}. The treatment of the royal cells where fertile workers lay the eggs of drones is very different. They begin indeed with bestowing every care on their eggs and worms; they close the cells at a suitable time, but never fail to destroy them three days afterwards.
Having finished these first experiments with success, I had still to discover the cause of the expansion of the sexual organs of fertile workers. M. Riems had not engaged in this interesting problem; and at first I dreaded that I should have no other guide towards its solution than conjecture. Yet from serious reflection, it appeared, that, by connecting the facts contained in this letter, there was some light that might elucidate my procedure in this new research.
From M. Schirach's elegant discoveries, it is beyond all doubt that common bees are originally of the female sex. They have received from nature the germs of an ovary, but she has allowed its expansion only in the particular case of their receiving a certain aliment while a worm. Thus it must be the peculiar object of inquiry whether the fertile workers get that aliment while worms.
All my experiments convince me that bees, capable of laying, are produced in hives that have lost the queen. A great quantity of royal jelly is then prepared for feeding the larvæ destined to replace her. Therefore, if fertile workers are produced in this situation alone, it is evident their origin is only in those hives where bees prepare the royal jelly. Towards this circumstance, I bent all my attention. It induced me to suspect that when bees give the _royal treatment_ to certain worms, they either by accident or a particular instinct, the principle of which is unknown to me, drop some particles of royal jelly into cells contiguous to those containing the worms destined for queens. The larvæ of workers that have accidentally received portions of so
## active an aliment, must be more or less affected by it; and their
ovaries should acquire a degree of expansion. But this expansion will be imperfect; why? because the royal food has been administered only in small portions, and, besides, the larvæ having lived in cells of the smallest dimensions, their parts cannot extend beyond the ordinary proportions. Thus, the bees produced by them will resemble common workers in size and all the external characteristics. Added to that, they will have the faculty of laying some eggs, solely from the effect of the trifling portion of royal jelly mixed with their aliment.
That we may judge of the justness of this explanation, it is necessary to consider fertile workers from their origin; to investigate whether the cells, where they are brought up, are constantly in the vicinity of the royal cells, and if their food is mixed with particles of the royal jelly. Unfortunately, the execution of these experiments is very difficult. When pure, the royal jelly is recognised by its sharp and pungent taste; but, when mixed with other substances, the peculiar savour is very imperfectly distinguished. Thus I conceived, that my investigation should be limited to the situation of the cells; and, as the subject is important, permit me to enter a little into detail{J}.
In June 1790, I observed that one of my thinnest hives had wanted the 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,