Chapter VIII (1)

RESEARCHES INTO THE ORIGIN OF MIXED OR COMPOUND ANT-HILLS.

The discovery of societies composed of different species, apparently living tranquilly together, was of but trifling consideration; an object of by far higher interest was, to ascertain the real nature and intent of this association, and to decide to which of the two casts the ant-hill appertained. The most effectual method of acquiring this information, was undoubtedly that of inspecting the interior of their common abode, and of thus coming to the fact, whether there were males and females of the two species, or of one only; as a previous step, it was however necessary to institute a comparison between the allied and rival ants, the Amazons, and the peaceable Ash-coloured Ants, and the latter intermixed with those of the same species, in simple ant-hills. The comparison, I would even say the confronting, of the Ash-coloured Ants in compound, with those inhabiting simple ant-hills, daily repeated, and often with the microscope, left me no doubt of their identity.

The Rufescent Ant, denominated by M. Latreille, _Fourmi roussâtre_, in every point answers the description of those that fell under my own observation. This author, having made, not only a genus apart, but a distinct class of these insects, from the simple inspection of their form, had, without knowing their manners, given the best proof of the distance which separates them from the dark Ash-coloured Ants. In the notes at the end of this work, a description is given of both species; I shall here, however, briefly describe them to prevent the trouble of recurrence. The former (_Fourmi roussâtre_) is one-third larger than the latter (_Fourmi noir-cendrée_); its head is of a square form, its abdomen short and globose, terminating in an obtuse point. It carries its head close to the ground, stands high upon its legs, and moves by a succession of jerks. The latter has a triangular-shaped head, which it carries in an horizontal position; its abdomen is an elongated oval, its feet are short, and its progressive movement more equal and uniform. The Rufescent Ant is of one uniform colour, from the antennæ to the extremity of the abdomen, of a red more or less falling into yellow, and more or less passing into a brownish tint according to its age; the whole of its body is, as it were, invested with a rich glossy varnish. The dark Ash-coloured Ant is sufficiently well described in its denomination; the rings of its body vary in colour from black to grey, the rest of the body is of an unpolished black, but that part lying between the thorax and abdomen (_l’etranglement_) is more frequently of the same colour; now and then it presents a yellow tinge, the feet are in colour a little paler. The mandibles or pincers of the Rufescent Ant, are very slender, arched, destitute of teeth, and present no concavity; those of the Ash-coloured Ant are large, broad, hollowed like a spoon, shaped as a gouge, and furnished with teeth on the margin. The eyes of the former species are very small, black, and round; those of the latter, rather large and oval. The scale is large and rounded in the one, large and triangular in the other; the Rufescent Ant is moreover provided with a sting, of which the dark Ash-coloured Ant is destitute. We see from this description how much these species differ.

Let us now pass on to the important research of the males and females, to determine who are the original tenants of the ant-hill, the Amazons, or the Negroes, for we must look upon those born there as the first occupants. From an inspection of the interior of one of these mixed ant-hills, I came to the knowledge of the singular composition of these republics. The Negro labourers, by far the most numerous, occupied the upper story of the building; they were guarding a multitude of pupæ, which appeared to be of two different species: some resembled those of the Negro Ants (probably what the Amazons had brought thither), others exhibited the perfect mould of the Martial Ants; these were larger than the preceding, their mandibles were slender and arched, their eyes small and black; added to this, they had every character of that species. There was also under the guard of the Negro Ants, a considerable number of larvæ, belonging to different species, admitting of easy distinction, from the curvature and thickness of the body. Descending another story, I perceived the Amazons collected in numerous groups, mingled with the Negroes; but what most interested me, and fully satisfied my curiosity, was, the finding among them little males, entirely black, with glittering wings, bearing no resemblance to those I had hitherto met with. At length I observed females of a large size, of an orange colour, whose similitude to the Rufescent Ants, clearly denoted their origin. The greater part possessed wings; in their body, eyes, and teeth, they closely resembled the Warrior labourers, but were of greater size. The males were not so large as those commonly found in simple Negro dwellings, and were unlike them, in not having either the feet or antennæ yellow.

In further examining the interior of this nest, which was of great depth and extent, I remarked that the Negroes were alone occupied in watching over these males and females, who allowed themselves to be conducted from place to place, as if they looked upon them as their natural parents. The Amazons, on the other hand, took not the slightest notice of them, but retired and hid themselves as quickly as possible. On looking around, I could see no traces of destruction, nor indeed any thing to justify a suspicion that the Legionary ants were endowed with a ferocious instinct, although one would be inclined to this belief from their martial disposition.

It seems sufficiently demonstrated by what we have seen of the contents of a mixed ant-hill, that _it belongs to the Amazons_, and that it is composed _of three sorts of individuals of that species_, and _of Negro labourers_. With all my care, I could perceive neither males nor females of this latter cast, but only young Negro working ants, and these I recognised by their colour. But whence does this proceed? Are the larvæ and pupæ taken away from the Negro Ants by the Amazons developed in the enemy’s encampment, and do they afterwards become house-stewards, and auxiliaries to the warlike tribe with whom they are associated? Every circumstance seems to prove that here rests the great mystery of their association with the Amazons: brought up in a strange nation, not only do they live sociably with their captors, but bestow the greatest care upon their larvæ and pupæ, their males and females, and even evince the same regard for them, transporting them from one part of the ant-hill to another, going in search of provisions for them, building their habitation; forming, as occasion requires, new galleries, and fulfilling the duties of sentinels, by guarding the exterior of their common abode, not once suspecting that they live with those very insects who have expatriated them.

Whilst the Negro Ants are thus engaged, the Amazons tranquilly wait at the bottom of their subterranean abode, the hour of departure, reserving their strength, their courage, and the tactic they so well know how to put in use, for the purpose of bringing in, from some neighbouring ant-hill, hundreds of larvæ, which they confide to those in charge of the household establishment; these, in their turn, are destined to become useful to the community.

The ants, whose habitation I had deranged, had already furnished me with some traits leading to a conjecture of these truths. When the Amazons, deceived by the strange appearance of their nest, were wandering over the surface, unable to find a retreat, the Negro Ants, who were incessantly occupied in forming new galleries, and who knew better than they the new localities of the ant-hill, drew them from their embarrassment by taking them up gently in their mandibles, and conducting them to the galleries already pierced. An Amazon was frequently seen to approach a Negro, and play upon its head with its antennæ, when the latter immediately seized it in its pincers, and deposited it at one of the entrances. The Amazon Ant then unrolled itself, caressed once more its kind friend, and passed into the interior of the nest. It now and then happened that a Negro Ant, engaged in carrying an Amazon, lost all knowledge of its route, wandering here and there without finding any entrance.

I observed one, after several ineffectual windings, take the precaution of laying on the earth the Amazon, who remained in the same spot until the Negro returned to its assistance, who, having well ascertained and examined one of the entrances, resumed its burthen, and bore it into the interior. If the entrance to any gallery was unluckily obstructed by a mass of earth, and the Negro Ant wished to introduce by that way one of the Amazons, it quickly deposited its load, and began clearing away the impediment; this was no sooner effected, than the Amazon was again taken up, and carried triumphantly into the nest.

If individual facts prove the harmony which reigns between these two species, living under the same roof, general facts fully illustrate what has been already stated.

We may readily see, from the appearance of mixed ant-hills, they are the sole work of the Ash-coloured Ants, although they are of greater extent than simple ant-hills, inhabited by that species, arising from their double population, and the prodigious number of auxiliary ants they contain. Their form, the architecture displayed in their construction, the substance of which they are composed, the interior arrangement, is altogether alike. I have frequently seen the Negro Ants of compound ant-hills take advantage of the rain to construct new stories upon their original domicile; they also often increase the extent of it by forming halls and chambers on the exterior margin; so that in three or four days they form, as it were, a new dwelling around the first enclosure.

The Legionaries never venture abroad, like the Ash-coloured Ants, during the rain, nor do they even, during that period, advance so far as the outer gallery; nor are any seen, as one would suppose, presiding over the masons, in their work; indeed, the Negroes require neither an inspector, nor the excitement of the sting, to induce them to labour; for they are eager to build whilst the rain continues, and their work advances rapidly, on account of their number being infinitely more considerable than that of the labourers in a simple ant-hill. Their operations being finished, they are extremely solicitous the Legionaries should enjoy the advantage; to this end, they lose no time in transferring the colony from the old to the new habitation. But if we are desirous of witnessing a still more curious spectacle, we must observe them when they are about to change their domicile for one more convenient, it being upon them alone the office falls of deciding the urgency of an emigration, and of choosing the situation best adapted (usually one where the soil is loose, admitting of greater facility of mining) for a new establishment. We see them at first engaged in carrying each other to the place destined to this object, where each Negro Ant either begins immediately clearing away the earth, or returns to bring away more of its comrades. When the new habitation is sufficiently advanced, they transport thither all the Amazons. We now see, in the road of communication between the old and new city, a file of Negro Ants, carrying the Legionaries, whose colour strikingly contrasts with that of their conductors. By these faithful guardians, the males and females are afterwards brought away in the same manner, and on their arriving at the entrance of the lodge prepared for them, are placed successively before the door, when other Negro labourers come forward and take them into the nest. The larvæ and pupæ are now taken away in their turn, and safely deposited in the new habitation.

In the morning these trusty servants go in search of provisions for the whole colony; at one time they bring back little dead animals, at another time return with their stomachs full of the liquor furnished them by the pucerons. They may be constantly seen going and coming on the road to the ant-hill. This is not the case with the Legionaries, for they never go in quest of the pucerons, and it is a rare circumstance should they venture forth during the early part of the day.

We have now taken a view of the Negro Ants or auxiliaries in the several offices of, procuring provisions for the republic, constructing a common abode, and conducting thither its varied inhabitants; the Amazons, a colony of soldiers, have, on the contrary, no other occupation, and no other talent than that for war; their manners are altogether distinct. They seldom leave their retreat, unless the temperature be above the 16th degree of Reaumur (67° of Fahrenheit) when placed in the shade. The general rendezvous commonly takes place a little before five in the evening: I have, however, sometimes seen them take their departure earlier, but never before two, nor later than five. They always return at six or half past six. They never quit their abode, unless the weather be fine.

These insects have but one object in their excursions, that of stealing the young from an industrious race, and making slaves of them; and these are the very individuals, who, after a time, labour for this Amazon colony, rear their young, and furnish them with provisions. This being the sole aim of the Amazons, they never seize any but larvæ and working pupæ, for the males and females would be useless. Nature would not assuredly allow the destruction of the habitations of Negro Ants, since this would be to involve in equal ruin those of the Amazons.

These warlike ants are sufficiently well acquainted with all the nests inhabited by Ash-coloured Ants in their neighbourhood, to each of which, in turn, they pay a visit. The route is every day varied, and, as already stated, the same nest is often pillaged several times successively; but they never destroy those ant-hills from which they have carried off the young. In the combats, that almost invariably take place, but very few Negro Ants perish, since their adversaries have no desire of making them prisoners, or of disputing the possession of their invaded city. I have sometimes seen the Amazons, when disposed in column, take one direction, then suddenly return to the garrison, and again proceed in a contrary direction. I have also witnessed their army, but very rarely, separate into two divisions, each taking a different route. The smallest division, however, on perceiving it is not in sufficient force, falls back, and rejoins the other; but when their force is nearly equal, each party goes to pillage separately, and returns to the garrison laden with booty. It is not so much by their real force, as by their impetuosity, that they succeed in spreading dismay among the Ash-coloured Ants; for I have seen an army, composed, at the most, of only one hundred and fifty Amazons, penetrate one of their habitations, and afterwards safely convey the purloined pupæ to their own citadel. What motive can possibly influence the Amazons in taking a certain route, or falling upon one ant-hill, in preference to another? To this I can give no direct reply. I once witnessed a Legionary Ant leave the nest before the hour of departure, apparently on a journey of discovery; I watched its movements for some time in the grass, and found it to visit every dry situation, and every place which seemed to announce the existence of an ant-hill, but I lost sight of it before its return. I have also seen a few return alone from a distant spot, and enter precipitately the garrison, when the army put itself in motion, and commenced a line of march precisely in that direction by which the couriers had arrived; however, I can, by no means, affirm this was the reason of their departure.

The signal they adopt is extremely varied; sometimes they strike against each other with their forehead or mandibles previous to the commencement of their march; at other times they appear to excite, by the play of their antennæ, a warlike ardour among their companions; it would appear that in this way a knowledge of their route is communicated, for it seems to be fixed at the moment of departure, since the army proceeds straight to its purpose. What is remarkable in the arrangement is, that none of the ants composing the troop move constantly in the same direction; on their arrival at the head of the column, they make a little circuit _en forme de boucle_, and re-enter the main body, then, as before noticed, return to the rear-guard, for the purpose of giving instruction to those behind. Eight or ten of the Amazons seek every opportunity of outstripping their comrades; these form the front of the battalion, but this they scarcely attain before they fall back into the general mass, and thus the advanced guard sustains a continual renovation.

I have never seen Amazon females in these armies: the neuters alone, as in all the other species, subject themselves to the chances of war. They do not march by groping or feeling their way, but run after their companions in arms, without any fear of straggling, and even should they do so, which is rarely the case, they are then brought back to the ant-hill by some of the Negro Ants, who, upon discovering them, seem sufficiently to understand the nature of their situation.

I was once present when the whole army appeared to be deceived in its route. It commenced its march after the ordinary manner; in place, however, of following a straight line, it described a curve, and reached a distance of about fifty paces, halting several times. After diverging on all sides, without discovering any of the usual objects of attack, they fell again into column, and returned by the same road to their garrison, reaping no advantage from their expedition. The decision they took of returning would furnish ample matter for reflection. I shall not now, however, enlarge upon this subject, but limit myself to the question, how can this fact be explained on the supposition of a blind instinct?[1] But here is a fact still more extraordinary. Upon their return our Amazons met with no flattering reception from the Negroes in the mixed ant-hill, who individually assailed, buffeted and dragged them to the outside of the nest, where they even obliged them to act on the defensive: this hostile disposition, however, continued only a few moments, when the Amazons were allowed to re-enter their citadel. Are we to conclude that the Negro Ants were surprised at seeing them arrive without their accustomed booty, or did the larvæ, &c. serve in their eyes as passports for those with whose fate their own was so intimately linked?

[1] There are few terms of more extensive signification than that of _instinct_. In its ordinary acceptation, it implies that principle which determines the conduct of animals in their several operations. Admitting, however, _all their ordinary operations_ to be regulated by such a power, what have we to say touching those instances (and many such are on record) where, from existing circumstances, the habits of the animals have undergone _a complete change_, and _recourse has been had to certain means to attain certain ends_. Man fondly arrogates to himself an active principle pervading his nature, denominated _mind_: that he should feel justly proud of this distinction, of that intellectual superiority which places him so high in the scale of animal existence, excites little surprise; but let him have the candour to imagine, that he, perhaps, is not the only being thus gifted; let him but allow a small portion of the same influence upon the lower order of beings, and we shall then have a rational theory to account for those occasional deviations from their natural habits that are inexplicable on the ground of instinct alone.--T.

The Legionaries never take animal food. I have often cast among them living insects, such as caterpillars, worms, &c., but never observed they touched them. I have also placed before them small pieces of meat, raw and roasted, from which they turned away with equal indifference, the Negro Ants seizing upon it at the moment.

Another experiment, which I frequently repeated, was that of placing my hand before the army when in march; the Amazons passed between my fingers, unalarmed at my presence; none attempted to pinch or sting me. We could not put to the same proof, with impunity, all other species of ants.[2]

[2] The Red Ants of this country, on being disturbed, become excessively angry, and fasten upon the hands and uncovered parts of the body, where they produce an almost intolerable itching, not much unlike that occasioned by the stinging nettle. From Perceval we learn, that the large Red Ants of Ceylon, which live on trees, and build their nests among the branches, bite very severely. This seems, also, to be the case with a black ant found in the same island, which, according to Knox, “bites desperately; as bad as if a man were burnt by a coal of fire.” Anderson, in his account of the natural productions of Van Diemen’s Land, states, among other insects, he met with two that were excessively troublesome, the mosquito, and a large black ant, whose bite, he observes, occasioned very severe pain. Sir Joseph Banks notices a green ant, which he saw in New South Wales, that produces a pain equal to the sting of a bee; and Stedman informs us, that, at Surinam, the Fire Ant (so called from the burning sensation it occasions) greatly annoyed the soldiers, making them leap about, as if scalded with boiling water.--T.

I have never seen the Amazons take nourishment but from the mouth of the Negroes. I have presented to them honey and fruit, which they left untasted. When hungry, they approach their auxiliaries, and these disgorge in their mouths the juices they have obtained in their daily intercourse with the _pucerons_.

An experiment that I tried upon the Legionaries convinced me of their dependance upon their humble companions, both for nourishment and habitation. I enclosed thirty of these ants, with several pupæ and larvæ of their own species, and twenty pupæ belonging to the Negroes, in a glass box, the bottom of which was covered with a thick layer of earth: I placed a little honey in the corner of their prison, and cut off all association with their auxiliaries. At first they appeared to pay some little attention to the larvæ; they carried them here and there, but presently replaced them. More than one-half of the Amazons died of hunger in less than two days. They had not even traced out a dwelling, and the few ants still in existence were languid, and without strength. I commiserated their condition, and gave them one of their black companions. This individual, unassisted, established order, formed a chamber in the earth, gathered together the larvæ, extricated several young ants that were ready to quit the condition of pupæ, and preserved the life of the remaining Amazons. This result needs no commentary: I leave to each the liberty of drawing his own conclusions.

CHAP. IX.

FURTHER INFORMATION ON THE AMAZON ANTS.

If any proof were still wanting of the origin of auxiliary ants in mixed ant-hills, the discovery of other habitations of this kind would, doubtless, throw much light upon this subject. I had not long been occupied, before I discovered such, in which the Amazons were the same, but the auxiliaries different, being of that species denominated Mining Ants.

The Mining Ants (_Fourmi mineuse_), who build after the manner of Negro Ants (of which I have already treated in the chapter on architecture), are a little larger than the latter, from which they also differ in the colour of the breast, which is of a bright red. The feet and antennæ are also of a reddish cast; in regard to the rest of the body, there is a close resemblance: but for the real distinction between these two species, we must look to their character. The Mining Ants possess great vivacity, are very courageous, and live upon animal food. The Negro Ants are, on the other hand, timid and pacific. It was not, therefore, without astonishment, that I saw, for the first time, an ant-hill, composed of Legionary and Mining Ants; it was at least thrice the size of the simple Miner ant-hills, and contained a vast number of inhabitants of the two casts. Among the individuals of this society, the same kind of intelligence seemed to reign as among those which had fallen under my previous notice.

The Mining Ants go forth in a crowd, from morning until evening, for the purpose of foraging in the neighbourhood, and thus providing for the wants of the colony: on their return they share the fruits of their industry with the Amazons, who are as idle in this community, as in that of compound Negro ant-hills. The Mining Ants, moreover, are alone employed in establishing a new domicile, and transporting thither the Rufescent Ants, their pupæ, their larvæ, and the rest of the colony, whenever they wish to change their abode; in a word, they are equally excellent labourers as the Negro Ants, and display much more zeal in defending their nest.

If compound ant-hills owe their existence to the pillage of the pupæ, the object of the Amazon Ants in their excursions would be, to attack the dwelling of Mining Ants, when their associates were of that cast, and of Negro Ants when they lived with ants of that species.

In the neighbourhood of the mixed ant-hill of which I have just spoken, comprising a circumference of more than fifty paces, there was no habitation of Negro Ants: but, of the Miner ant-hills there was great abundance. This, therefore, was a sufficient reason for believing, that the ants of that species, living with the Amazons, drew their origin from these several colonies. To be assured of this, I visited a compound Miner ant-hill, between four and five in the evening, a time when the army usually commences its march: the Amazons were already assembled on the nest, and ready to set forth; they proceeded like a torrent along a deep dyke, and marched in a more compact body than ordinary. In a short time they reached the nest they proposed to attack, which was inhabited by Mining Ants. As soon as the Legionaries began entering the subterranean city, the Miners rushed out in crowds, and whilst some fell upon the invaders with great spirit, others passed through the scene of contest, solely occupied in bearing off to a place of safety their larvæ and pupæ. The surface of the nest was for some time the theatre of war. The Legionaries were often despoiled of the pupæ they had seized by the Miners, who darted upon them with amazing spirit, fighting body to body, and disputing the ground with an exasperation I had never before witnessed. The Amazon army was, notwithstanding successful, and recommenced its march in good order, laden with pupæ and larvæ: instead, however, of proceeding in file, it now maintained close rank, forming a compact mass, a precaution the more necessary, as the courageous insects upon whom they had made this attack, hastened in pursuit, and even harassed them, to within ten paces of their citadel.

During these combats the pillaged ant-hill presented, in miniature, the spectacle of a besieged city: hundreds of its inhabitants were observed to quit it, carrying here and there the pupæ, larvæ, and young females they were anxious to preserve from the fury of their enemies. The major part mounted the neighbouring plants, bearing the young between their teeth; others deposited them under the thick bushes. When the danger was entirely gone by, they brought them back into the city, and barricaded the gates, near which they posted themselves in great number to guard the entrance. All was calm, however, in the mixed ant-hill; the Amazons had entered quietly their abode, and had been received by the auxiliary ants as the real proprietors.

Immediately after, the Legionaries again departed, and proceeded towards a Miner ant-hill of considerable extent, considering themselves in sufficient force to cope with the guardians of that habitation: they threw themselves _en masse_ upon one of the galleries indifferently guarded; but their number not permitting them to enter all at once, the Mining Ants that were without, immediately precipitated themselves upon the invaders: and whilst they were engaged in desperate combat, their fellow-citizens in considerable number, losing, perhaps, every hope of defending their abode, and the little ones confided to their care, left the nest with the pupæ, larvæ, and youngest ants, took flight in every direction, and literally covered the ground to a considerable distance. The contest became every moment warmer: here the Amazons were endeavouring to seize the pupæ, which the Miners were removing from the seat of war; there the besieged were observed to wrest from the conquerors the fruit of their rapine. Confusion was at its height; Legionaries and Miners attacked each other impetuously, and often in the excess of their fury, deceived as to their object, fell upon their companions, whom, however, they immediately released. This commotion was confined to the rear-guard of the Legionary army; the main body, richly freighted, left the devastated city, and forming into square battalion, retraced their steps to their own citadel, constantly assailed by the Miners, who, for some time, continued the pursuit. It is only by their address, the rapidity of their movements, and the use of their sting, that the Legionaries are enabled to disengage themselves. I have often remarked, during these combats, the females of the Miners take flight, bearing off the pupæ in their mouths, acting in this respect like simple workers; but have never known them to take any share in defence of their nest. The pillage and skirmishes are not of long continuance; for in less than a quarter of an hour, we find the Amazons on the road to their garrison. Notwithstanding the courage and exasperated state of both parties, but a trifling number of ants perish.[1]

[1] If, according to our author, but few ants perish on the field of battle, I am inclined to think, that a considerable number die of the wounds and injuries they receive, shortly after their return to the nest.--T.

This scene, brilliant for its extent, was renewed as often as the Amazons found the temperature friendly to their departure. The purloined pupæ are soon developed: and not knowing their real family, (like the Negro Ants in mixed ant-hills,) bestow all their care upon the offspring of the Amazons.

Here then are two distinct species of auxiliary ants, in whose form and character we trace no resemblance, affording a favourable opportunity for solving the question, relative to the composition of these ant-hills. If in compound Negro ant-hills, and in compound Miner ant-hills, we find males and females _of but one species_, we must, of course, conclude, they have no relation to the auxiliary ants, but only to the Amazons; indeed those which I saw carried on several occasions by the Mining workers, in their emigration from one nest to another, in every respect resembled the little males and large females, met with in mixed Negro ant-hills: and I have looked in vain for others in the same habitation. I have even been present at the time of their leaving their abode, and can affirm, notwithstanding researches the most assiduous, attention the most unwearied, I never yet perceived any which were not in every respect like those I have described. Their departure and the circumstances attending it is by no means a point of indifference. For several successive days they come to the surface of the nest, surrounded by the Mining Ants, who form their escort, and take the same care of them as the workers in simple ant-hills, of the males and females of their own species. At length they quit the nest and commence their aërial excursions.

On the 31st July, at half-past ten in the morning, I saw several little black males issue from a compound Negro ant-hill, accompanied by a considerable number of Negro Ant labourers. The number of males were continually increasing; several Amazons on this occasion also left the nest, and came among them, although it was to them an unaccustomed hour; they approached the males and licked them after the manner of the Negro Ants. At length the large females came forth from the citadel, climbed the neighbouring plants, and in their turn received from the Negro Ants and the Amazons, the same attention as the males. At eleven o’clock the males became extremely restless, ran against and overturned each other, beat the air with their wings, and finally finished their gambols by taking flight. The females followed their example. More than fifty females, and four times as many males, quitted the nest. I kept guard for some time thinking they would return; but I never saw them more.

The appearance of this ant-hill was both satisfactory and pleasing; the contrast of females of a fine yellow colour, with little males entirely black; of winged insects with neuters destitute of wings; and of Amazon labourers, living in friendly union with such a number of Ash-coloured Ants, presented a picture full of interest, notwithstanding the trifling size of the objects that composed it.

In compound ant-hills I have now and then observed some very remarkable individuals which may be seen delineated in Pl. 2. fig. 1. These are Rufescent Ants, equalling, in size, females of the same species, differing only in the form of their thorax, which is not enlarged, and destined to bear wings; it resembles that of the labourers. These individuals are, from their size, classed with females, but they do not possess wings. I should have assigned them a place among the labourers, had I ever seen them take part in their excursions.[2] Here then is another example of those transitions we have remarked between the females and labourers of some insects of the same genus. Among bees there are several modifications of queens; there exist, also, among humble bees fecund labourers of different degrees of size, resembling, in almost every respect, females. This fact comes in support of those already given, and must convince us, that females and labourers are originally of the same order, and do not owe their form and real character, but to the more or less complete developement of their organs. I know not if the individuals, of which I have just spoken, are capable of laying, nor can I state the purport of their creation; be this as it may, they are extremely rare, and have no relation with the Ash-coloured and Mining Ants, in mixed ant-hills, where we equally find them.

[2] “It is remarkable,” says Gould, “of common yellow and hill-settlements, (alluding to the nests of _F. flava_ and _F. rufa_,) that you will find two sizes of workers in most of them, the larger exceed the less about one part in three; but there is no apparent difference as to contexture or other circumstances. They are mutually interspersed all over the colony, and carry on the same offices of labour and employment.” This observation of Gould is confirmed by specimens in the cabinet of Mr. Kirby. This gentleman informs us, that he saw them labouring in the colony, and that the large workers of _F. rufa_ are nearly three times, and of _F. flava_ twice the size of the small ones.--T.

Let us now return to the winged females. A little time after quitting their natal abode, they lose their wings like the ants of other species, traverse the ground, and seek a place of shelter. I could have wished it were possible to follow them; for their history, especially that part of it which relates to their new progeny, strongly excited my curiosity. To ascertain how these several colonies exist on their first formation, is a task of extreme difficulty: how, at this period, can they associate themselves with auxiliary ants, not being in sufficient force to make the necessary incursions to procure them? How, under these circumstances, do they act or can they do without them? Not being able to answer these questions, I shall adduce some proofs, showing that the Amazons are more skilful in the domestic arts than idlers, or those habituated to a life of ease.

Monsieur Latreille, more fortunate than myself, found one of these newly formed ant-hills. After giving a description of the Rufescent Ant, (of which we have been accustomed to speak under the name of Legionary or Amazon Ant,) he observes, “This species is exceedingly rare; I never observed it in society but once, and this society consisted only of a few members. It runs remarkably quick, and makes its nest, I believe, in the earth.” Had there been any association with the auxiliary ants, this careful observer would doubtless have noticed and been much struck with it.[3] I look upon it, therefore, as an almost certain fact, that the Rufescent Ants, before they are accustomed to the services of the Ash-coloured and Mining Ants, can put in use faculties which lie dormant when they become associated with these auxiliaries. It even happens they will sometimes assume their office, that is, change parts with them: a fact of which I have been once, and once only, a witness.

[3] Since this passage was written M. Latreille has frequently witnessed these mixed societies, or the association in one common abode of the Rufescent Ants with its auxiliaries, (the Ash-coloured and the Mining Ant). He takes the opportunity of paying a high compliment to our Author for this discovery.--T.

A compound ant-hill was established a short time since, on the terrace of the house in which I resided. I carefully observed the excursions of the Amazons, and one day remarked, they directed their route to a deserted ant-hill: the ants who had previously occupied it, pillaged doubtless too often by their so much dreaded neighbours, had taken the precaution of decamping with arms and baggage. The Amazons, who were perhaps badly lodged, profited by this circumstance. After having visited it, they returned, took up in their mouths the Negro Ants of the mixed ant-hill, and transported them to the new habitation. This operation lasted some hours, and the emigration was completely effected in this manner.

In this instance I saw the inverse of what I had hitherto observed, but never experienced the gratification of witnessing a repetition. The Amazons carried the Ash-coloured Ants as the latter usually carry them. The whole colony being transferred to the new lodging, they there rested, and each species again returned to their ordinary duties.

We see, from this example, that it is highly probable the Amazons know more than they would seem to know; and if we have seen them perish of hunger rather than take the trouble of providing for themselves, we must attribute it to the custom of their receiving nourishment immediately from the Ash-coloured Ants, and never going themselves in search of it.

Those who live in small numbers with their maternal parent, not being as yet accustomed to an idle life, do not, probably, confine themselves to the sole occupation of war, but engage in domestic duties; for during a certain period, the ant-hill is entirely composed of Amazons. But when their number shall have given them confidence, they are then seen to sally forth to procure the pupæ of the Ash-coloured and Mining Ants; which, under their management, become auxiliaries and useful companions. These are only conjectures, and perhaps very distant from the truth. I know, however, of none more plausible to explain the formation of new Amazon ant-hills.

As to the preservation of compound ant-hills, I believe it consists, as in all other ant-hills, in reserving some pregnant females to keep up the population. I have often seen in these habitations, and in all seasons, females destitute of wings. I opened, in the middle of April, some of these dwellings, where I found a considerable number of eggs, agglutinated together, assiduously guarded by Negro Ants. I also noticed some Amazon females, surrounded by the same guardians. They inhabited the most elevated part of the building, and the eggs were collected near them. In the month of June I first perceived the male pupæ in their enveloping membrane; their larvæ being in the number of those that spin: the female pupæ were rather later in appearing. They were liberated from their envelope, by the Negro labourers, in the same manner as the pupæ of Ash-coloured and Mining Ants, a little time before their last transformation. It is only in the month of July they pass into that state which puts them in a condition for flying. The pupæ of the Amazon Labourers were at that time very numerous in all their nests, but I no longer found there the pupæ of Ash-coloured and Mining Ants. The pupæ which the Legionaries had purloined the preceding year, were developed before autumn; their last invasions occurring in September. These warrior ants have only two months and a half to collect all the pupæ of which they stand in need. The temperature is often sufficiently high in May and the beginning of June to allow of their departure; they do not, however, venture abroad until their males are on the point of undergoing their transformation: they sometimes leave the nest individually, and are then always stopped by the Negroes, who bring them back to the ant-hill. I know not from what motive this conduct on the part of the auxiliaries arises; I have often remarked it, and it is a certain fact, that the Legionaries never go to pillage before that period. If they began earlier to purloin the larvæ and pupæ belonging to the Negro Ants, they would make great booty; it would, however, be in a great degree composed of the pupæ of males and females, and these it seems, they are not permitted to seize. Nature, aware of the serious inconveniencies that would arise from an attack made at this time by the Amazons, particularly guards against it, by producing the males and females of those ant-hills destined to pillage at a much earlier period than the males and females of the martial ants, and in not permitting the latter to be engaged in acts of rapine, until the metamorphosis of the winged insects has taken place.

The Ash-coloured and Mining Ants, are to be considered then as the negroes of the Amazons; it is from among them the latter procure slaves; they kidnap them at an age when their instinct is not developed; and these insects, on being brought up by the Amazons, divide with them the fruit of their industry. Can we sufficiently admire the prudence and wisdom these insects display in the establishment of such an institution! We here trace neither servitude nor oppression, nor do the ants themselves, taken from perhaps twenty different dwellings, entertain the slightest suspicion of their being in a foreign nest: they live under the same roof in brotherly and sisterly union, and if they regard the Amazons, it is but to show them greater attention. Nature, profound in her combinations, seems fully aware that old ants would never live sociably with those of another species, but that young ants may, especially if they have been accustomed in early life to see and receive from them some attention. She seems, also, aware, that no aversion is excited in the breasts of those who witness their birth. It is in this way, she has instituted mixed or compound ant-hills: it is on this account the Amazons in their expeditions never carry off adult ants, only larvæ and pupæ; for the same reason, they never seek the destruction of their enemies, their only aim being to steal from them their little ones.

An important truth relative to the moral condition of these insects, rests upon these facts--that their instinct is capable of receiving several modifications. Ants, carried away in their youth, may become familiar, and even live with an hostile species; it is in the first period of their life those impressions are formed which they always preserve. The very same objects that would naturally have excited their hatred, now only inspire them with a sentiment of love.

CHAP. X.

ESTABLISHMENT OF A MIXED ANT-HILL IN A GLASS APPARATUS.

I had often established, with success, artificial ant-hills, and am indebted to them for several interesting observations on the Fallow, Yellow, and other ants. I now resolved upon making the attempt of fixing, in an apparatus of the same kind, a colony of Amazon Ants, with their auxiliaries. The knowledge I had already acquired upon mixed ant-hills greatly facilitated my views. In describing the particulars of this experiment, the manners of these two species will be completely developed.

I constructed an apparatus, to which, for the sake of abridgement, I shall, as formerly, give the name of _ruche_. It consisted of a double vertical frame, twenty inches in length, by ten in depth, glazed on both sides; the distance between the two frames was only ten lines. I found this, however, too great, and, therefore, lessened it by placing a sheet of tin, drilled in numerous places, parallel with the two glasses. On the fore-part of the _ruche_ was a vertical portcullis, which could be raised or lowered at will, thus answering as a door. (This apparatus should not be raised upon feet, like those I have before described, but should be so constructed as to rest immediately upon the earth, by means of two very strong _liteaux_, inserted in the bottom of the _ruche_, and projecting, on each side.) Two wooden shutters excluded the light, and several holes, drilled in the upper part of the apparatus, allowed of my presenting honey to the ants, or pouring water into the interior, as often as it should be judged necessary. It was in this _ruche_, of which we may see a figure in Plate 1. that I thought of establishing a mixed ant-hill; and was desirous the ants should settle there of their own accord. To render them less sensible of the singularity of their abode, I filled the lower half of this apparatus with fine and slightly moistened earth, and deposited honey in several places.

These preparations being finished, I chose one of the most populous mixed ant-hills, in which were many males and young Amazon females. I removed a great part of this nest, placed it in a large linen bag, and then carried it to my study.

I established between my prisoners, and the lodging they were to occupy a free communication by means of a little canal of wood glazed on its upper surface, having one of its extremities inserted into the bag, and the other into the door of the _ruche_. This done, I left the ants to themselves. On the following morning I saw some of the Ash-coloured Ants leave the bag and enter the _ruche_ through the glazed canal. In the evening more passed. The second day they commenced carrying each other into the apparatus. Their number augmented hourly. At length the canal scarcely sufficed for the crowd of insects going and returning; it was obstructed by the recruits, and these were, for the most part, engaged in transporting the Legionary Ants from the bag to the _ruche_.

Having this glazed conduit, I was not obliged to open the shutters to see what was passing. The advantage of this arrangement was, that of not alarming the ants, whilst it assured me of their forming an establishment in the artificial ant-hill, preparing lodgings there, and removing the useless materials, such as flints or pebbles, and pieces of earth too dry to be put in work. I found from this, that it was necessary to moisten the earth in the interior, and, therefore, poured water through the holes in the upper part of the apparatus, which completely answered (as will be presently seen) all my wishes.

By the fourth day, the whole of the ants appeared to know the road, and had ceased to carry each other. But as I observed many re-enter the bag, I was fearful they might take the whim of fixing themselves there: I, therefore, obliged them to return into the _ruche_. With this view, I separated the bag from the glazed canal, and scattered gently all the earth it contained upon the floor near the artificial ant-hill. I constructed all around a brick wall, and reduced between my fingers the several clods; so that the ants could not conceal themselves. I then re-fixed one end of the glazed canal to the door of the _ruche_, placing the other end on the ground; forming an inclined plane, in such a way that the ants could go out and find their companions roving in the enclosure. The Ash-coloured Ants actually descended by this passage, and immediately brought back into their new abode the stragglers. They looked for them in every corner, visited the smallest clod of earth, examined scrutinously the remains of their former nest, and thence drew their companions of both species, taking them up in their mouths and transporting them immediately to the _ruche_. This operation finished, I went out to find the rest of the nest which I had left in the field, and then dispersed it in my study; a few of the Ash-coloured, or Negro Ants, in the _ruche_, perceiving fresh arrivals wandering about the floor, came out, and carried them into the new habitation. I was much astonished on seeing several ants leave the apparatus at the same time, as if they had been told there were many ants still to bring in. They immediately put themselves to work, constantly arriving with their companions of both species suspended by their mandibles, or setting off in file to seek those who still remained unsheltered: whilst these were thus engaged, their companions constructed galleries in the heap of earth I had brought in, and disengaged a great number of labourers, larvæ, and pupæ, which were there imprisoned. They worked with indefatigable activity. I was struck by their zeal. They brought to my recollection those famous dogs, who appear associated in charity with their masters, for the purpose of extricating from underneath the snow of the Alps engulphed travellers.

The Legionary Ants took no active part in this interesting scene: the Negro Ants were particularly careful of them, often conducting them into the interior of the nest, but sometimes contenting themselves with laying them down at the entrance of the glazed canal, going immediately in search of others. The Rufescent Ant, in this case, remained, for a moment, curled up, without movement; it then unrolled itself, and looked around, on all sides, without knowing where it was, or what direction it should take. I saw it, then, approach the Ash-coloured Ants, and implore their assistance, by the aid of its antennæ, until one that had little to do, seized and carried it into the nest.

In eight days the _ruche_ was completely peopled, and I was in hopes I had acquired a sure means of observing what passed in the interior of these singular republics. I hastened, then, to submit it to the proof. For this purpose, I carried out my _ruche_, and placed it upon the grass, allowing its inhabitants the full liberty of leaving it. I confess this was not done without some degree of apprehension; for I might thus lose, in one moment, the fruit of all my care; but I was encouraged by the hope that the Ash-coloured Ants attached to their work, would not abandon it so readily.

The first day, the Negro Ants, availing themselves of their liberty, visited the environs of their abode. They returned, just as I could wish. Some individual Amazons, also, went out, but were quickly brought back by their auxiliaries. On the day following, the Ash-coloured Ants guarded their door very assiduously; they heaped up many pieces of stone, &c. to narrow it, and thus oppose the entrance of certain ants attracted thither by the odour of the honey. They went, also, in search of the _pucerons_.

In the evening, the air being extremely warm, and the sun shining upon the ant-hill, I saw the Amazons prepare for an expedition. The whole army descended by means of the glazed canal. The signal being given, they set forward in an entire body, and fell upon a nest of Ash-coloured Ants, situated a few paces from the _ruche_. The Amazons returned with the success usually attending these incursions. Each disposed of his load at the door of the artificial ant-hill, into which the Ash-coloured Ants immediately introduced it. The warlike ants returned directly to carry off the rest of the larvæ; and, as it was only a trifling distance to the scene of pillage an uninterrupted chain of Amazons was established; some going to seek the pupæ, whilst others were bearing them away. At length they re-entered their own habitation, but came out in a quarter of an hour, and made their last attack upon the ant-hill, purloining, this time but a very few larvæ, and retiring tranquilly to the _ruche_.