Chapter VI: Introduction (3)

The insect, in the state of pupa, has acquired the figure it will always preserve; nothing seems wanting but strength and a little more consistence: it is also as large as it will ever be; all its members are distinct, one single pellicle envelopes them. The ant, under this form, continues to move for some moments after its quitting the state of larva, but it soon becomes immoveable: it afterwards changes gradually in colour, passing from a fine white to a pale yellow; then becoming red, and in several species, brown, almost verging to black. The rudiments of wings may at this time be seen in those which are destined to fly. The pupæ have still many attentions to receive from the workers; the greater part are enclosed in a tissue spun by themselves before their metamorphosis; but they cannot, like other insects, liberate themselves from this covering by effecting an opening in it with their teeth. They have scarcely the power of moving; their covering is of too compact a texture, and formed of too strong a silk, to allow of their tearing it without the assistance of the workers. But how do these indefatigable attendants ascertain the proper moment for this process?--If they possessed the faculty of hearing, we might imagine they knew the fit time, from some noise produced in the interior of the prison by the insects whose developement has commenced; but there is no indication favouring this opinion; it is probable they have a knowledge of it from some slight movements that take place within, which they ascertain through the medium of their antennæ; for these organs are endowed with a sensibility, of which it would be difficult to form a just idea: whatever it be, they are never deceived.

Let us still follow them in that labour, wherein are displayed, as it regards their charge, a zeal and an attachment which would justly merit our attention, even were they the real parents of these insects; how much greater then must be our astonishment, when we consider that they bear no further relation to them, than that of being born under the same roof. Several males and females lay in their enveloping membrane in one of the largest cavities of my glazed ant-hill. The Labourers, assembled together, appeared to be in continual motion around them. I noticed three or four mounted upon one of these cocoons, endeavouring to open it with their teeth at that extremity answering to the head of the pupa; they began thinning it, by tearing away some threads of silk where they wished to pierce it; and at length, by dint of pinching and biting this tissue, so extremely difficult to break, they formed in it a vast number of apertures. They afterwards attempted to enlarge these openings, by tearing or drawing away the silk; but these efforts proving ineffectual, they passed one of their teeth into the cocoon, through the apertures they had formed, and by cutting each thread, one after the other, with great patience, at length effected a passage, of a line in diameter, in the superior part of the web. They now uncovered the head and feet of the insect to which they were desirous of giving liberty, but before they could release it, it was absolutely necessary to enlarge the opening; for this purpose, these guardians cut out a portion in the longitudinal direction of the cocoon, with their teeth alone, employing these instruments as we are in the habit of employing a pair of scissars. A considerable degree of agitation prevailed in this part of the ant-hill; a number of ants were occupied in disengaging the winged individual of its envelope; they took repose and relieved each other by turns, evincing great eagerness in seconding their companions in this undertaking.[8] To effect its speedy liberation, some raised up the portion or _bandalette_ cut out in the length of the cocoon; whilst others drew it gently from its imprisonment. When the ant was extricated from its enveloping membrane, it was not, like other insects, capable of enjoying its freedom, and taking flight: nature did not will it that it should so soon be independent of the labourers. It could neither fly, nor walk, nor without difficulty stand; for the body was still confined by another membrane, from which it could not, by its own exertions, disengage itself.

[8] Among those ants I kept in confinement, I observed that considerable bustle prevailed when any of the pupæ were about to quit the cocoon. For the most part, two or three stationed themselves on or near each cocoon. From seeing, more than once, two engaged in the operation of extricating the imprisoned ant from its envelope, I was desirous of ascertaining whether a single worker could accomplish this operation. I therefore placed in a wine glass with a little moistened earth one of the Yellow Ants with three or four pupæ; the first object with this little creature, was that of excavating a chamber for the deposition of its treasure. The pupæ were then brought up, and laid on the surface of the earth, from day to day, to receive the sun’s warmth. In a few days, I saw the scattered remnants of one of the cocoons, and the worker with his assistant engaged in giving liberty to the remaining ants. I did not, at the time, notice whether the pupæ were or were not capable of effecting their own liberation; but according to the statement of De Geer, the pupa dies when neglected by the workers.--T.

In this fresh embarrassment, the labourers did not forsake it; they removed the satin-like pellicle which embraced every part of the body, drew the antennæ gently from their investment, then disengaged the feet and the wings, and lastly, the body, the abdomen, and its peduncle. The insect was now in a condition to walk and receive nourishment, for which it appeared there was urgent need. The first attention therefore, paid it by the guardians, was that of giving it the food I had placed within their reach.

The ants in every part of the ant-hill were occupied in giving liberty to the males, females, and young labourers, that were still enveloped. On being dispossessed of their coverings, the remnants were collected and placed aside in one of the most distant lodges of their habitation; for these insects observe the greatest order and regularity. Some species of ants remove these shreds to a distance from the ant-hill, others, cover the exterior surface of their nest with them, or collect them in particular apartments.[9]

[9] M. Latreille has remarked, as well as De Geer, that, among the Ash-coloured Ants, there are some pupæ which are naked, others enclosed in a cocoon; but he does not know if there are any that undergo their metamorphosis without spinning, or if the workers tear off their enveloping membrane; however he leans to this latter opinion. I have often made the same remark. I have even confirmed the conjecture he had advanced, and often seen the ash-coloured labourers opening the cocoon of the pupæ, a short period after their transformation. The Mining Ants act the same: but for what purpose do they hasten to liberate them, and of what advantage is it to the larvæ to spin, if the workers so soon destroy the tissue they have woven? It cannot be for the sake of unfolding their members from the last envelope in the state of pupæ, for the ants do not render them this service until they are capable of motion, and have acquired their full strength: they even know the precise moment when to remove them. Are not these cocoons of essential service to the larvæ at the time of passing to the state of pupæ? I have frequently drawn from their cocoons, larvæ which had just spun, and which were not yet metamorphosed: some days after, they began rejecting their larva-skin, but could not disengage their limbs, which, with the abdomen, remained attached to it. The ants offered them no assistance. These pupæ were never well developed, and they soon perished. It appears that these cocoons offered them a point of support, enabling them to free themselves from the skin which they are under the necessity of rejecting. It will be objected, perhaps, that the larvæ of several species never spin, and they would of course experience the same inconvenience as those I drew too hastily from their cocoon. To this I answer, that nature has provided for this case in another manner:--the body of these Ants is very different from that of others, their elongated peduncle gives greater liberty to the abdomen, to move, bend, and extend itself, than the peduncle of the first, which is closely attached to the corslet. They have, in addition, a sting, which may also facilitate their developement, for the pupæ at first possess much strength and vivacity, although they soon after pass into a state of lethargy.--A.

The labourers we have seen in charge of the larvæ and pupæ evince the same solicitude for the ants, freshly transformed: they lie for some days under the necessity of watching and following them; they accompany them in their excursions, point out to them the paths and labyrinths of their habitation, and nourish them with the greatest care; they also perform the difficult task of extending the wings of the males and females, which would otherwise remain folded up, and acquit themselves with such address, as not to injure these frail and delicate members.

At one time, they bring together, in the same apartments, the males they find rambling; at another time, act as guides in conducting them from the ant-hill. In short, the labourers appear to have the complete direction of their conduct, as long as they remain there, and neglect not to discharge the several duties, connected with these insects (whose strength is not yet developed) until the period of their taking flight for the purpose of continuing their kind.

How can we sufficiently admire the assiduity which the labouring ants evince for the little ones whose safety is confided to them!--By what bond has nature attached them so strongly to the progeny of another mother! This question having a reference to the different families composed of three sorts of individuals,--the labourers, charged with educating the young, fabricating, and provisioning the nest; and those upon whom the office devolves of multiplying the species,--deserves to be treated at greater length, and with greater attention, than our confined knowledge permits. But we have a glimpse, however, of the secret of this singular constitution, in the resemblance the labourers have with the female ants, relatively to their external sexual organs. The connexion which exists between ants, and hive and humble bees, throws additional light upon this subject, by showing us labourers demi-fecund with the one[10], and little rival females, abundant enough with the other.[11] That solicitude also which the labouring ants evince for the larvæ, whose birth they have witnessed, clearly discovers their sex, and would be sufficient to prove that they are neither neuters nor males, even if the conduct of the males towards them did not indicate that they belong to the class of females. This observation, which I have several times made, (the details of which I suppress,) leaves me in no doubt upon this point. I shall here only add, that I have never known the labouring ants produce eggs, and have constantly found the approach of the male attended with the sacrifice of their lives.

[10] Nouvelles Observations sur les Abeilles, par F. Huber.

[11] V. Linn. Trans. vol. vi. Memoir upon Humble Bees, by the Author of these researches.

But with what view does nature permit as many sterile females among ants as among wasps and bees? Is it not in order to increase the number of individuals, in the same family, without producing a population that would be more than proportioned to it?--In reserving a certain number of females for conception, she has appointed others to take care of the infant generation. She has even deprived the latter of the faculty of flying; but in return for this, they enjoy a sweet recompense, either (as we have no reason to doubt) by their being inspired for their charge with the sentiments of mothers for their young, or by their having an unlimited power over the other orders of the society in which they live; a truth which I hope to establish in the course of this work, and which differs widely from the received opinion, that these republics are governed by several chiefs.

CHAP. III.

OF THE FECUNDATION, &C. OF ANTS.

1. _Departure of the Winged Ants._

Were we unable to determine the sexes of ants from the appearance of those light and membranous wings with which some are furnished, and others totally unprovided, we should still conclude, that the former were destined to change their place of abode, the latter to remain on the spot where they receive their birth. That prerogative which distinguishes the males and females from the workers, has not been granted them for the advantage of the colony in which they pass the first period of their existence. They are neither called upon to provision their abode, nor to seek, afar off, materials for its construction. Nature has endowed them with instruments of flight, for the well-being and continuance of the species, and for the purpose of establishing ant-hills in every situation, and forming numerous colonies. But how are these new colonies established? What particulars do the amours of these winged ants offer us? Do the males and females live in common? Have they the same instinct as the workers? What a variety of questions could we not propose on this subject; a subject hitherto but slightly touched upon, and by comparatively few authors, and whose importance, as it regards the economy of ants, merits the closest attention.

Having observed these insects in the interior of the ant-hill, remarked their education, and the cares bestowed upon them, to the period when they are in a condition to walk or fly, we shall now follow them out of the nest, and, as far as possible, in their aërial excursions.

Let us lose sight for one moment of the glazed ant-hill. Let us retire to a meadow, on a fine summer’s day, at a time when they first make use of their wings, and take a survey of their habitation, on the surface of which we shall observe walking to and fro many of its winged inhabitants. These are the males and females of the Field Ants; they climb all the plants which surround their residence, and are every where accompanied by a multitude of workers, who follow their steps with ceaseless solicitude. Some, however, attempt to retain and reconduct them to the ant-hill; but the greater part content themselves with simply escorting them. They offer them nourishment for the last time, and render them the last token of their care and affection.

The dome of the ant-hill does not afford the winged ants a sufficiently ample field for the display of their amours; the crowd by which they are constantly surrounded seems to embarrass their movements; they soon come to the determination of taking flight, and seeking in the air a wider theatre, in which they can accomplish the wish of nature. But what are those dazzling objects we see on that little hillock rising above the grass? They are the male Ants who come forth by hundreds from their subterranean residence, and display their silvery and transparent wings as they wander over the surface of their nest. The females, who are in much smaller number, soon join their paramours, proudly displaying their big and highly bronzed abdomen, and occasionally extending their glittering wings, whose ever-varying lustre adds much to the beauty of this interesting assemblage.

Disorder and agitation are now manifest in the ant-hill; the bustle increases every moment, the winged insects climb with great briskness the neighbouring plants, followed by a numerous retinue of workers, who are continually running from one male to another, touching them with their antennæ, and offering them food.

The males, at length, quit the paternal roof and take flight, as from one general impulse, in which they are quickly followed by the females. The winged tribe soon disappear. The workers retrace for some instants the steps of these highly favoured beings, to whom they have shown such extreme care and attention, and whom they are never destined to see more.

Many pleasing pictures are exhibited by the variety in colour and form of this assemblage of insects. In some, the whole body is of one uniform colour; the workers being yellow, the males black, and the females flaxen. Their wings display all the brilliant hues of the rainbow. In others, the body of the workers is of a dark ash-colour, stained with red upon the corslet; the males, whose body is a deep black, have the feet of a fine yellow, and the wings whitish; the females have the corslet and abdomen brown, ornamented with orange-coloured spots; the wings are transparent and blackish at their extremities.

It is requisite that the temperature of the air should be at the 15° or 16° of Reaumur (67° Fahrenheit), to allow of our witnessing the departure of the males and females: unless this be the case, they continue within the nest, sheltered from the wet and the cold air. When the weather is favourable, the labourers, who seem to be aware of it, form several apertures in the ant-hill, to give a ready passage to the crowd that are about to quit it. The males and females may be then seen coming to take the air at the entrance. The hour of departure arrives: they all take flight. The workers alone re-enter the nest, and close the entrances.

But let us continue our course, and still follow the winged ants in their flight. A shower of these insects soon arrests the attention. They fall from some height in the air, by pairs, roll themselves in the dust, and sport in the grass. With some, the junction takes place previous to their reaching the ground; with others, it is effected upon the plants where they rest; some few disengage themselves from their companions, and, mounting in the air, rejoin a cloud of other winged ants, collected near the top of a tree, around which they make continual evolutions. A little further off, I perceive other assemblages of these winged insects, but of a different species; they appear at a less height than the former, and somewhat resemble the swarming of bees. The term of swarm, however, does not strictly apply to this concourse of insects, who have no further object than that of meeting each other, and effecting their union in the air, and who do not assemble for the purpose of founding a new colony. I shall, notwithstanding, use this expression, when speaking of a numerous assemblage of ants, who fly about with a buzzing sound, without separating. I presently perceived I was surrounded by winged ants: several females were in the midst of this swarm; and these are they who, doubtless, draw together all the males of which it is composed. The swarm takes no particular direction, neither removing from, nor approaching the ant-hill they had left; but, in place of this, raise and lower themselves alternately, about ten feet from the surface of the ground. Whilst this general movement takes place, which is effected with considerable slowness, all the males forming the main body of the swarm, fly in a zig-zag direction, with considerable rapidity: the females, on the contrary, remain suspended, like balloons; they face the wind, and seem in a state of immobility. They continue, however, to ascend and descend with the swarm, until the males dart upon them, separate them from the crowd, and impregnate them, even in mid-air.

I have often noticed, in the month of September, similar swarms. These insects admitted of easy observation, since they were unembarrassed by my presence. The sound produced by myriads of these insects did not equal that of a single wasp. In every part of the meadow, these assemblages might be witnessed: a zephyr was sufficient to disperse them, but they quickly reformed a compact body. It often happened several swarms were so intermingled as to constitute but one. I have seen very considerable swarms, but ascertained nothing particular respecting them.[1]

[1] Assemblages of winged ants have been also witnessed in this country, as is evidenced by the following quotation:--“In the beginning of August, 1812, I was going up the Orford river, in Suffolk, in a row-boat, in the evening, when my attention was caught by an infinite number of winged ants, both males and females, at which the fish were every where darting, floating alive upon the surface of the water. While passing the river, these had probably been precipitated into it, either by the wind, or by a heavy shower, which had just fallen. Captain Haverfield, R. N., gave me an account of an extraordinary appearance of ants observed by him in the Medway, in the autumn of 1814, when he was first-lieutenant of the Clorinde, which is confirmed by the following letter, addressed by the surgeon of that ship, now Dr. Bromley, to Mr. Mac Leay:--‘In Sept. 1814, being on the deck of the hulk of the Clorinde, my attention was drawn to the water by the first-lieutenant (Haverfield) observing there was something black floating down with the tide. On looking with a glass, I discovered they were insects. The boat was sent, and brought a bucket full of them on board; they proved to be a large species of ant, and extended from the upper part of Salt-pan reach, out towards the great Nore, a distance of five or six miles. The column appeared to be in breadth eight or ten feet, and in height about six inches, which, I suppose, must have been from their resting one upon another.’ These ants were winged. Whence this immense column came was not ascertained. From the number here agglomerated, one would think that all the ant-hills of Kent and Surrey could scarcely have furnished a sufficient number of males and females to form it. When Colonel Sir Augustus Frazer, of the Horse Artillery, was surveying, on the 6th of October, 1813, the scene of the battle of the Pyrennees from the summit of the mountain called Pena de Aya, or Les quatre Couronnes, he and his friends were enveloped by a swarm of ants, so numerous as entirely to intercept their view, so that they were glad to remove to another station, in order to get rid of them.”--_Introduction to Entomology_, by Kirby and Spence, Vol. II. p. 53.--T.

When a large body of these insects were hovering immediately over my head, it would seem that I alone possessed the power of inducing them to change their station, and of uniting them to others I observed in the meadows. To effect this, I had only to walk slowly, the swarm by which I was surrounded following and accompanying me in all my movements, which I attribute either to my drawing after me the column of air in which they were flying, or to their regarding me as the base above which they were elevated, and, therefore, not aware of their removing from the point of departure. I have never witnessed any of those extensive swarms, of which M. Gleditsch has given us an account, in the Memoirs of the Academy of Berlin. “He observed,” he says, “an immense swarm of ants, which, viewed at a distance, produced an effect very much resembling an aurora borealis, when, from the border of the cloud, appear by jets several columns of flame and vapour, attended with a variety of luminous rays and lines, forming no unapt resemblance to forked lightning, although destitute of its brilliancy. Columns of ants, but less distinct, were seen moving here and there, with inexpressible swiftness, continually elevating, so that they at length appeared to soar above the clouds. Arrived at this point, they so far from totally, or even in part disappearing, seemed to form a more compact body, becoming darker, from time to time. Other moving columns, but more dilatory in their progress, followed the first, rising, in like manner, occasionally darting forth, or mounting after each other with equal swiftness. These several columns continued in motion during the space of half an hour. Each column presented a species of close net-work, and had an intestinal or undulating movement. On regarding them a little nearer, I found them to consist of a numerous body of flying insects. These insects, of small size, entirely black, and winged, preserved the form of an unbroken column, continually ascending and descending with great regularity.”[2]

[2] Bomare, Dict. d’Hist. Nat.

One would be inclined to believe, that these winged ants, whose aërial excursions are completed, and whose impregnation has taken place before us, recalled to the ant-hill, by an instinctive impulse, would return to increase the population of their nest; that the males, now useless, after consuming a part of the provisions of the large family of which they are members, would experience the cruel fate attending those of bees, and that the females would commit their eggs to the charge of the same individuals who protected them in their infancy. Several authors entertain this opinion, (among others De Geer); but they advance nothing in support of it. It will be therefore expedient to discuss the question which naturally arises from these facts.

The male and female ants, when they take a long flight from the ant-hill, do not show that singular instinct which guides bees, wasps, and other insects, in again finding their habitation. This instinct consists, in their knowing how to move in every direction around their abode, without straggling, in order to examine its position, and the several places in its vicinity. We may be soon convinced of this by displacing a hive. The first day the bees never venture abroad, unless they have previously visited all the neighbouring objects: they turn round on all sides, keeping an eye upon their dwelling, without which, it may be readily conceived, it would be impossible they could return. The Queen Bee does the same when she goes forth to meet her paramour in the air.[3] But our winged ants, on the contrary, when they quit the ant-hill, keep their back continually towards it, and go off in a right line to a distance, from which it would be no easy matter to perceive it. We might from this infer, that they would never return to it. But I did not confine myself entirely to this observation; for I kept sentry, from the time of their departure until night, and even several days in succession, to be fully assured they did not return to the ant-hill. In this way I have arrived at the conviction, that their return is one of those fables with which we have been a long time amused. What, then, becomes of these insects, accustomed as they have been, to live in a convenient spacious abode, sheltered from every inclemency of the weather, and receiving every attention from the labourers, suddenly relying upon their own guidance, deprived of all these advantages? This we shall learn in the following section.

[3] _Vide_ Observations upon Bees, addressed to Ch. Bonnet.

2. _History of Winged Ants after Impregnation._

The history of males, after they have discharged the only office to which they appear destined, neither offers any proof of that courage we should expect from their sex, nor of a laborious industry. We know that in the class of insects with four membranous wings, the males are destitute of offensive weapons, and do not possess that admirable apparatus which the greater part of females put in use in the establishment of their family; they have neither chisel-shaped teeth, nor stings, nor ovipositors (_tarières_). The several arts we remark among the greater number of bees and wasps, ichneumons and tenthredines, &c. are exercised by the females alone, or by the labourers, their representatives. The defence of the nest is also confided to them: the males, after attending to the office of reproduction, become useless to the family of which they are members. The life of male ants cannot be of long duration; deprived of their attendants, incapable of providing their own subsistence, and returning no more to the ant-hill that gave them birth, how can it possibly be of any long continuance? Their life is either naturally limited to a few weeks, or hunger will speedily terminate it: whatever it be, they disappear in a little time after the period of their amours; but they never fall victims, as happens with bees, to the fury of the labourers.

At the period when the career of males is terminated, that of the females is scarcely commenced: they bear the germs of future generations, and these germs are fecundated. Their history is closely connected with the history of ant-hills, and embraces several curious, and hitherto unknown, particulars. Let us at first pass in review those authors who have treated of it.

Swammerdam, to whom we are indebted for many excellent memoirs on the metamorphoses of insects, and who was one of the first to point out those which ants undergo, had never seen among them any winged females; he, however, describes some of the species; he speaks of the males being provided with four wings, and mentions several facts in their history. Geoffry has witnessed wings upon females, but he denies their ever being deprived of them. There are individuals who still believe, as in the time of antiquity, that ants, at a certain age, acquire wings. Linnæus, De Geer, Latreille, and other modern naturalists, agree in stating, that the females of ants have wings, as well as the males, and that in a little time after copulation, some are seen destitute of these organs. This observation, repeated by so many learned naturalists, is well entitled to our confidence. Swammerdam must, therefore, have been deceived. By means of the glasses in my artificial ant-hill, we have traced from its first commencement the developement of their wings; we have seen the ants take flight, unite in the air with the males, and hover in the midst of the swarm, which is almost entirely composed of male insects. It would be difficult to be mistaken in facts of this nature.

It has also been stated, that there are females without wings. Indeed, every time I have opened ant-hills, I have found some entirely destitute of these organs. Are these the females that are at one time in the number of flying insects, and at another time reduced to the condition of labourers? For what end, and how do these insects lose their wings? In the following observations will, I think, be found the solution of this problem.

One day, with the view of ascertaining the precise condition of the females, I visited certain ant-hills, which I knew to be filled with winged ants, of both sexes, and whose departure could not be very distant. Scarcely had I reached the spot, when I saw pass over my head several female ants, bearing the males behind them. I seized a few, without injuring them, and found they belonged to the Brown Ant. Having then approached the ant-hill, from whence I had seen them depart, I observed several take flight, and quit their natal abode. The males preceded them, and the labourers, as far as they could, accompanied them. These females took a direction perpendicular to the horizon, and were soon lost to sight. When they encountered the males sporting in the air, they re-descended with their light burthen, and alighted upon some shrubs. These couples soon separated.

I took eight females, still united with the males, and placed them in a box, to observe them on my return; but a violent rain, which came on at this moment, offered me a sight, as singular as unexpected. As soon as the shower had passed, I saw the earth strewed with females without wings. They were most likely the identical females I had seen traversing the air. They were of the same species and colour as the first. I had not quitted the place in which the ants had alighted. Some still retained their wings; it was, therefore, an easy matter to compare them.

On my return home, I placed my eight prisoners, with some moistened earth, in a garden vase, covered with a glass receiver. It was nine o’clock in the evening; at ten all the females had lost their wings, which I observed scattered here and there, and had hidden themselves under the earth. I had allowed the occasion to pass by, of witnessing the separation of these fragile members, and of determining, if possible, what had produced it.

On the following day, I procured three other females in union with their males, and this time I observed them with the greatest attention, from the moment of their fecundation, until nine in the evening; a period of five hours. But during this time nothing was done to denote the approaching loss of their wings, which remained still firmly affixed. These females appeared to be in excellent condition: they passed their feet across their mouths, then glided them over the antennæ, and rubbed the legs one against the other. I could not conceive what could retard the fall of their wings, whilst the other ants had lost them so readily. It is true, that I placed those of which I am now speaking, in a very strong box, completely closed, whilst the former were deposited in a transparent vault, offering not the slightest appearance of a prison, and upon a ground more natural than the bottom of a sand-box, where there was no earth. I had no idea that a circumstance so trifling would have any influence upon these ants; however, having learned that it was necessary to place them as the first, I took some earth, and strewed it lightly over the table, and then covered it with a bell-glass. I yet possessed three fecundated ants, one of which I introduced under the recipient. I induced her to go there freely, by presenting to her a fragment of straw, on which she mounted, and upon this I conveyed her to her new habitation without touching her; scarcely did she perceive the earth which covered the bottom of her abode, than she extended her wings, with some effort, bringing them before her head, crossing them in every direction, throwing them from side to side, and producing so many singular contortions, that her four wings fell off at the same moment, in my presence. After this change she reposed, brushed her corslet with her feet, then traversed the ground, evidently appearing to seek a place of shelter; she seemed not to have the slightest idea that she was confined within a narrow enclosure. She partook of the honey I gave her, and at last found a hiding-place under some loose earth, which formed a little natural grotto.

If I was surprised at seeing this female strip herself of her wings voluntarily, I was even more so, on finding that she did not appear to suffer from it, and that, after an act which would seem to us any thing but natural, she delivered herself peaceably to her appetite, and sought a retreat, as if nothing out of the ordinary course had happened. This fact merited confirmation.

I introduced a second female under the bell-glass about two hours after the first, and with the same precaution, adding to the dry earth, strewed over the table, a little water, in order to allow these insects to undertake any labour to which their instinct might prompt them. When she perceived that she stood upon moistened earth, she advanced a few paces, then stopped to touch the ground with her antennæ. This done, she took a position to facilitate the dispossession of her wings; resting on her abdomen, she opened them in disorder, extended them in every direction, passed her legs behind them, and pressed them closely towards the ground. When she had succeeded in disembarrassing herself of these organs, I observed her walk about tranquilly in her enclosure, and begin constructing a grotto in the earth: thus, this second experiment had all the success of the first.

I still possessed one pregnant female, which I reserved for the following morning; she had not lost her wings before the experiment. I introduced her under the recipient fifteen or sixteen hours later than the others: she appeared to be in excellent condition, and apparently had not suffered by this delay. Scarcely had she touched the ground, than she hastened to get rid of her wings, employing the method already described. I repeated the like experiment on several females of different species, and always obtained the same result.[4]

[4] For the discovery of the female ants voluntarily depriving themselves of their wings, after impregnation, we are certainly indebted to our present author; but, as far as regards the simple fact of these insects losing their wings, Linnæus, De Geer, &c. were fully acquainted with it; to which indeed our author alludes. Gould himself conjectured, that the females which fell under his notice once possessed wings. After a few remarks on the condition of what he terms ant-flies, he says, “If you strip a large ant-fly of its wings, when a week old, or more, which is very easily done, for they will come off by the most gentle touch imaginable, and then place it in a microscope with a queen, you will perceive no manner of difference as to their frame; the like indented places, or little hollows in the breast where the wings commonly lie, will be found in each; from whence, there is great reason to believe the queen was originally adorned with such gaiety, and appeared in the character of a fly. It is also observable, as a strong confirmation of this sentiment, that abundance of the large ant-flies, just before or soon after leaving the colonies, actually drop their wings, and, except a small difference in complexion, which has not yet attained its true gloss, are not to be distinguished from the queens. You may, the latter end of July, and great part of August, often meet with these unwinged ants, travelling about, as it were, at random. If you place a number of large ant-flies in a box, the wings of many of them will, after some time, gradually fall off like autumnal leaves. This circumstance is peculiar to the large sort; for if you confine the small ones ever so long, their wings will continue fixed, and cannot be separated without some difficulty.” In another place, he observes, “the casting of their wings is an instance peculiar to the large ant-flies. These are to other insects their highest decorations, and the want of them lessens their beauty and shortens their life. On the reverse, a large ant-fly gains by the loss, and is afterwards promoted to a throne, and drops these external ornaments as emblems of too much levity for a sovereign.”--T.

We see, then, that the females of ants lose their wings, but we little expected they would themselves be the voluntary authors of it. Would it not appear that nature takes delight in sporting with our judgment in the variety and superiority of her plans, in the detail as well as in the aggregate? We only judge from known facts; but nature does not follow, and indeed is under no necessity of following, any invariable rule: the fruitful source from which she receives her laws knows no limits: every species has its own manners, every individual its own particular constitution; hence arise the innumerable errors into which we fall, the moment we leave the high-road of observation to be guided by what appear to us general rules. But let us return to the history of ants, which furnishes us many examples of the inefficiency of our conjectures.

What will be the destiny of those ants who have been united with the males in the air, and who have just mutilated themselves? We already know they never return to their natal abode.

As soon as they have lost their wings, we observe them running over the ground seeking an asylum. It would be extremely difficult at this time to follow them, on account of the several turnings and windings they make in the fields, and among the grass. I have not succeeded in tracing them at the moment of their first establishment, but I rest perfectly assured, from some experiments, that those females who are not called upon to discharge any duty in the natal ant-hills, and who appear incapable of acting by themselves, animated by maternal love, and the need of putting in use all their faculties, become industrious, and take care of their little ones with the same sedulous attention as the common labourers.

I enclosed several pregnant females in a vessel full of light humid earth, with which they constructed lodges, where they resided; some singly, others in common. They laid their eggs and took great care of them; and, notwithstanding the inconvenience of not being able to vary the temperature of their habitation, they reared some, which became larvæ, of a tolerable size, but which soon perished from the effect of my own negligence.

I afterwards placed some other females in a similar apparatus, and delivered to them some pupæ (labourers), to ascertain if their instinct would teach them to open the covering in which they were enclosed. Although these females were virgins, and provided with wings, they laboured so well, that I found, on the following morning, three workers among them. Some days after I saw them occupied in delivering other labourers from their last envelope: they acted in the same way as ordinary ants, and did not appear embarrassed in the part which they now performed for the first time.

It is, therefore, evident, that females, in case of necessity, are enabled, unassisted, to educate their family. If I have endeavoured to assure myself of this fact by proofs still more positive, it was less to remove any doubts on this point, than to satisfy my curiosity on the composition of these new colonies.

After long researches, I discovered the retreat of these females, and the nascent ant-hills they had established. They were situated at a little depth in the earth. A small number of workers were seen by the side of the mother, and some larvæ which they nourished. I have seen two examples of these newly established colonies. One of my friends, M. Perrot, of Neufchatel, a very excellent naturalist, whose observations claim my greatest confidence, discovered, one day, in a little underground cavity, a female ant, living solitarily with four pupæ, of which she appeared to take great care.[5]

[5] “Upon frequent opening of mole-hills,” says Gould, “amongst them, I met with three, in each of which was a cluster of large female ants, amounting to six or seven in a cluster. They lay near the surface, but had no regular apartment. Upon examining, and comparing them with a queen, there was an exact agreement in colour, form, and structure. Upon dissection, several of them had parcels of eggs in their insides. I deposited one of the clusters in a box with some earth, under which they concealed themselves, and united together, but did not work any lodgement. Some time after, three or four of these females laid a few eggs, but did not seem to take any great notice of them. For curiosity, I placed in the box a cell of workers of the same species; and it was surprising to observe what fondness was expressed. The common ants immediately surrounded the females, took care of the eggs, and, in a short period, made an apartment in the earth fit to receive them. It may also be observed that there were no common ants in the hills where I found the above clusters. In all probability they were originally large ant-flies, which, having been expelled their colonies, and not falling victims to their adversaries, associated together in this manner, and survived the winter.”--There is no doubt but these mole-hills were fixed upon by the females for the establishment of new colonies; and from their consisting of loose earth, and presenting several cavities, the labour of these insects in constructing a dwelling must be considerably lessened. It is highly probable, they had lately arrived there, and, therefore, had no time to commence their architectural operations, it being remarked they had no regular apartment. It would seem, by the above statement, that the females go in small parties to found new colonies, as well as singly; which must have happened with the female which fell under the notice of M. Perrot. The female which this gentleman saw, was engaged in tending her young. This certainly appears, on a first view, at variance with Gould’s remark, that the females which laid eggs “did not seem to take any great notice of them.” But it must be recollected, that the females were not placed under similar circumstances: the former having been discovered with her young in her own residence; the latter having produced their eggs in confinement, and doubtless fully conscious of it.--T.

There still remains another important question to solve--Would those females, who had not received the addresses of the male also deprive themselves of their wings, or would they continue to use them?

I took, at the end of April, from a nest of Yellow Ants, several young females; their wings were unfolded, and of a whitish hue, like those recently removed from their envelope. They enjoyed full liberty in their habitation; which proves, as we shall presently see, that they were still virgins. We know, moreover, that it is a very rare occurrence should the males impregnate them in the interior of the nest. I enclosed them in a glazed ant-hill, with some labourers of the same family, and observed their conduct during several months. The labourers were far from evincing the same degree of interest for them as for pregnant females: they appeared to treat them with indifference; and this was the more natural, as these females had adopted the manners and character of the neuters. Their timidity had disappeared, and given place to a sort of boldness, or rather irascibility, which I perceived every time I opened the door to give them nourishment; they darted forth upon my hands, and even pinched me more strongly than the labourers: they knew, also, how to follow and catch the flies I introduced into their nest; and did it with much promptitude and dexterity: but they did not lose their wings, notwithstanding the long proof to which I subjected them.

At another time, I placed several female virgins of the species of Brown Ants, with a portion of their nest, under a bell-glass. They remained there peaceably without taking up the choleric disposition of the preceding; but these also preserved their wings.

I also placed ten other ants, equally virgins, in a vase, where I left them six weeks. During this long captivity, they did not even attempt to dispossess themselves of these members, which were still left to fulfil the object of their destination.[6]

[6] I kept in captivity, upwards of a month, four female ants, two of the Yellow and two of the Brown species: they still retained their wings. These members would seem to be employed on no other occasion than when they seek the males in the air, and search for a situation favourable to a new establishment. I have often endeavoured, in their natal residence, by irritating them, to induce them to take flight; but never could succeed. It was, however, in this instance, scarcely to be expected, since the _amor patriæ_ would restrain them. I have removed them to a distance from the ant-hill, and placed them in the sunshine; but all to no purpose. It, therefore, appears, they neither dispossess themselves of these members until their impregnation has been effected, nor make use of them, unless for the sole purpose of meeting their paramours in the air, and seeking a place for the establishment of a new colony.--T.

It appears to me, then, certain, that the females do not reject their wings, but after fecundation; and that this act is, on their part, completely voluntary, when they are to change their mode of life, and withdraw to take all due care of the colony of which they bear the future germs.

3. _The Conduct of Labourers towards the Pregnant Females._

All the females do not quit the metropolis: it is necessary some few should remain to keep up the population. We shall now see in what manner nature guards against that desertion of females with which the ant-hill is threatened.

In speaking of the swarms of ants, I avoided making an observation, which required some developement, and which comes in now in its proper place. It is this: that the union of the sexes does not always take place at a distance from the ant-hill. It ordinarily happens, that the males, before setting off, leave in the ant-hill a few impregnated females. The labourers, as if fully aware of the importance of preserving females capable of maintaining the population of the republic, carefully retain these valuable depositaries of a future generation. Of this remarkable feature of their foresight or instinct, I have been a frequent witness; not only on natural ant-hills, but even in my glass apparatus, where I observed it under more detail. I removed the bell-glass which was placed over them, because I perceived it concentrated the rays of the sun upon the nest to that degree, that its inhabitants could not support it, and removed my glazed ant-hill to the garden, where I could observe the winged ants as if they were in full liberty. The greater number of the females quitted the nest, and never returned to it. A few remained upon the nest, and were there impregnated. One, after copulation, was about to take flight, when the labourers retained her by her feet, kept her down by main force, tore off her wings, and conducted her back to her residence, where they obstinately guarded her. Several others were seized by the labourers, even in the very act of copulation, and immediately carried off to the bottom of the frame, where I saw them mutilated, and retained in captivity.[7]

[7] De Geer observed in a nest of Red Ants that the workers compelled some females, that were come out of the nest, to re-enter it. I visited twice or thrice a day, for some time, a colony of Red Ants, and never observed any male or female in it. The workers were engaged in taking care of the pupæ, which were in considerable number. What was my surprise, to observe, at length, a mass of eggs apparently just laid, which the workers, on my disturbing their abode, carried off with amazing expedition. It does not seem likely that any female, after her excursion in the air, should have alighted on their dwelling, since they generally go and found new colonies. It is more probable this was one of the females born in the nest, and, at the time of the males and females taking their departure, had been retained by the workers, in one of the lower apartments, for the sake of maintaining its population.--T.

It is more especially with the Fuliginous Ants, that we can the more readily observe this proceeding, since the departure of the winged individuals of that species does not take place for a very considerable period; previous to which the male and female insects go out each day from their labyrinths, from two or three o’clock in the evening, until the middle of night, walking along the trunk of the tree they inhabit. The movement of those insects whom the labourers lead out of the nest, progressively increases, and resembles a national fête, in which all the individuals of the ant-hill take an active part: it is destined to favour the rencontre and union of the sexes. I have often seen, in those numerous gatherings, females retained by the workers, mutilated in my presence, and carried back to the interior of the trunk; and, although I have not surprised them in their embraces, I have no doubt their imprisonment took its origin from their fecundation, which I conjecture must have taken place, from the other ants remaining perfectly free, from analogy with those ants of which I have before spoken, and from my having several times seen the males follow the females to the surface of the tree.

We see, then, that this numerous _cortège_ of labourers, which we have often observed, without knowing their purport, is not a homage they render the winged ants, but is destined to favour the seizure of those females whose impregnation takes place upon the very nest.