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fined 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.'

Huber repeated these experiments on several female ants of different species, and always obtained the same result. Here we see, then, that in some instances the neuters forcibly detach the wings of the females; in others, that the act is a voluntary one self-inflicted by the females themselves. The mutilation when performed by the neuters takes place only in those cases in which the female ant is caught and forcibly detained by them. The wings of the females are very slightly articulated, much more slightly than are those of the males, so that but little effort is necessary to detach them, and doubtless very little pain is felt during the operation.

We have already seen that those female ants which have taken flight and have been fertilised in the air never return to their former abode; only those remain who have been fertilised on or near the ant-hill. What becomes then of the aerial fecundated females? Carried away by the wind to a distance from their natal ant-hill, it is perhaps scarcely probable that they shall ever find it again. But then they might easily find other ant-hills to which they might seek admittance. But alas! as amongst mankind, ants do not always treat their neighbours with kindness and hospitality; on the contrary, not only do they refuse to entertain a female stranger hospitably, they even attack and murder her. Should an unprotected female' by chance find her way to a neighbouring ant-hill, even though the inmates may belong to her own species, she is almost certainly to be killed. I have often had occasion,' says Forel, to see fecundated females of pratensis, cæspitum, and fusca 'which had been running in the meadows to fall into the middle of an ant-hill of their own species and there to be killed by 'the neuters.' Only once or twice did Forel succeed in persuading neuters to receive females of another ant-hill; more readily they will ally themselves with strange neuters than with the females. Should one or two neuters, however, which by accident had lost their way, fall in with one of these females, they will not attack her; they will either get out of her way or seek to form an alliance. In the midst of great danger from enemies, what are the females to do? They seek out a convenient spot and hollow out a small house, in which they lay their eggs, which to some extent they watch over; these nascent ant-hills are situated at a little depth in the earth; according to Huber, sometimes they are constructed by a single female ant, sometimes by several in common. A small num

ber of neuters are generally seen by the side of the mother. Whence have these neuters come? Are they the first-hatched eggs of the mother herself which have already developed into neuters, or have they proceeded from elsewhere? Forel says that no positive case of a new ant-hill population (fourmilière) founded by a single fertilised female is as yet known. M. Perrot, however, assured Huber that he once found in a little underground cavity a female ant living solitary with four pupa, of which she appeared to take great care.' But Forel limits the nursing and rearing capabilities of the females themselves: 'pondent des œufs qu'elles soignent à moitié, sans savoir les 'mener seules à bien; they lay eggs which they partly care for, without knowing how to bring them to good,' i.e. 'to rear 'them.' Forel is supported by Gould, who says of some three or four females under his observation which had laid eggs, that they did not seem to take any great notice of them." These neuters of a nascent nest are, therefore, probably a few individuals that had wandered from some ant-hill and had allied themselves with the female in her newly made abode. The females which have been fertilised on or near to the nest are at first forcibly kept in the nest by the workers, but after a few days they get accustomed to their captivity and do not seek to go away. Sometimes there is only one female in the nest, at other times there may be as many as twenty or thirty; these lay eggs which will bring neuters and females the following year; they are generally attended by a court of neuters who lick them, feed them, take up their eggs, &c. The different females of the same ant-hill show no jealousy nor rivalry; each has her court, they pass each other uninjured ' and sustain in common the population of the ant-hill, but they possess no power, which it would seem entirely lodges. with the neuters. The numbers of eggs deposited by the females vary according to the species; the relative size of the 'abdomen will give a fair idea; some lay thousands, others but 'few. Forel considers the ordinary duration of life of both fertilised females and males is about one year. We must not forget to mention the presence of a certain number of female ants in a nest, which are not destined to become mothers; these do not voluntarily tear off their wings; neither do the workers do it for them; these virgin-ants act the part of neuters, and it is not long before the wings get torn away by working in the soil; they are to be recognised by their agility compared with that of the other females, and the small size of their abdomens; they do not receive honour from the neuters, and are not sur

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rounded by a court; compared with the intense activity of the neuters, these females may be considered rather lazy.

What becomes of the male ant after taking flight and leaving the abode which he will never visit again?

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.'

Nothing perhaps in the character of ants is more striking than the ferocity with which they fight, and of all the enemies those most dreaded are the ants themselves; the fury of these insects and the tenacity they exhibit in retaining hold of an enemy is perfectly astonishing; the ant is the bull-dog amongst insects; it would be more easy to tear away their limbs and cut them in pieces than separate two hostile combatants. Here walks some individual with manifest proof that he has been in the wars, for he carries suspended to one of his legs the head of some foe whom he had conquered, and which he carries about as a pledge of victory! There goes another worker dragging along the body of a foe which not even in death would relax his hold!

'Ants make their attack openly; cunning is not in the number of their arms; those of which they make use are the saw-pincers they employ for carrying the materials of their nests, a sting resembling that of bees, and the venom which accompanies it, an acid liquid contained in their abdomen, which produces a slight irritation on the skin. These arms are only possessed by the females and workers to whom nature has confided the several interests of the colony. The females, doubtless too valuable to allow of their exposing their lives, always make their escape on the slightest danger. The workers are those only destined to defend their habitation. Several species are unprovided with a sting, but they supply its place by biting their enemy and pouring into the wound they inflict with their teeth a drop of venom, which renders it exceedingly painful. They bend for that purpose their abdomen, which contains the venomous liquid, and approach it to the wounded part at the very same moment they tear it with their pincers. When their adversaries keep only at a distance, and they are unable to reach them, they will raise themselves on their hind feet, and bringing their abdomen between their legs, spurt their venom with some degree of force. We see ascend from the whole surface of the nest a thick cloud of formic acid, which exhales an almost sulphureous odour.' (P. 183.)

We have had before us each day for some time past some

ants (Myrmica ruginodis) under observation in a glass vessel, and have frequently witnessed their conflicts. Introducing some individuals of the same species but from a different nest, we soon see numbers to engage generally in single combat. The ants seem to recognise each other and to distinguish friend from foe by crossing their antennæ; that done, if friends meet, they pass on; if enemies, immediately the fight begins. We have over and over again witnessed that kind of combat, which Forel designates combats à froid, or combats chroniques.

'These combats,' he says, 'almost always begin by what I shall call pullings (tiraillements); the ants seize themselves by the feet or by the antennæ, and pull themselves without violence, without great efforts, but with a wonderful tenacity; they keep continually touching each other with their antennæ. In this case the two adversaries never pour poison over each other nor bend their abdomens. Nearly always one of the adversaries is patient, the other active; the first, without defending itself, submits with a stoical resignation; the other acts almost as the Indians do to their prisoners; it seizes an antenna of its victim, and endeavours, with a coolness truly infernal (avec une tranquillité vraiment infernale) to cut it, or rather to saw it off with its mandibles; that done, it cuts off a leg, or the other antenna, one after another, until its victim, frightfully mutilated but quite alive, is utterly unable to defend itself or even to guide itself; then it sometimes makes an end of it by cutting off its neck or thorax, but generally it drags it off and places it in some lonely spot, where it necessarily perishes. Not once only, but more than a hundred times, I have made this sad observation. A less unpleasant modification of this act takes place when the stronger ant, wishing simply to disengage itself from the other, without doing it harm, carries it as far as possible and leaves it, and hastens to return.' (Forel, p. 247.)

M. Forel has recorded a great many kinds of battles; sometimes they take place between ants of different species or between those of different genera, or those of the same species, but of different ant-hills. It is most extraordinary how in this latter case the ants can distinguish between friend and enemy. One day we placed a number of ants (F. fusca) with their cocoons in a glass vessel with a number of Myrmica ruginodis. The latter attacked fusca most vigorously, which ran up the sides of the glass trying to escape; on examining the lot a few days afterwards, we saw several dead neuters, but not a vestige of their cocoons, which had doubtless been devoured by the stronger or more valiant enemy. Space forbids us to do more than give Huber's description of a fight between regular armies, the occupants of two large ant-hills of the same species (F. rufa), alike in their extent and population, situated about a hundred paces from each other.

VOL. CXLV. NO. CCXCVII.

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'Let us figure to ourselves this prodigious crowd of insects covering the ground lying between these two ant-hills, and occupying a space of two feet in breadth. Both armies met at half-way from their respective habitations, and there the battle commenced. Thousands of ants took their station upon the highest ground and fought in pairs, keeping firm hold of their antagonist by their mandibles; a considerable number were engaged in the attack and leading away prisoners. The latter made several ineffectual efforts to escape, as if aware that upon their arrival at the camp they would experience a cruel death. The scene of warfare occupied a space of about three feet square; a penetrating odour exhaled from all sides, numbers of dead ants were seen covered with venom. Those ants composing groups and chains took hold of each other's legs and pincers and dragged their antagonists on the ground. These groups formed successively. The fight usually commenced between two ants, who seized each other by the mandibles and raised themselves upon their hind legs, to allow of their bringing their abdomen forward and spurting the venom upon their adversary. They were frequently so closely wedged together that they fell upon their sides and fought a long time in the dust; they shortly after raised themselves, when each began dragging his enemy, but when the force was equal the wrestlers remained immovable and fixed each other to the ground, until a third came to decide the contest. It more commonly happened that both ants received assistance at the same time, when the whole four, keeping firm hold of a foot or antenna, made ineffectual attempts to gain the battle. Some ants joined the latter, and these were, in their turn, seized by new arrivals. It was in this way they formed chains of six, eight, or ten ants, all firmly locked together; the equilibrium was only broken when several warriors from the same republic advanced at the same time, who compelled those that were enchained to let go their hold, when the single combats again took place. On the approach of night each party returned gradually to the city which served it for an asylum. The ants which were either killed or led away captive, not being replaced by others, the number of combatants diminished until their force were exhausted.' (P. 189.)

Connected with their wars is the very remarkable instinct which leads certain species of ants to capture slaves and appropriate their labours for the duties of their own nests. Pierre Huber was the first to discover this in the case of Polyerges rufescens, a species which, strange to say, is absolutely dependent upon captured neuters of another species for their means of living. The labours of the neuters of Polyerges are strictly confined to slave-capturing; they are incapable from long disuse of doing any other work; they cannot make their own nests, nor feed their larvæ. Huber has shown by an experiment how entirely dependent upon other ants are the neuters of this species, both for nourishment and habitation.

'I enclosed,' he says, 'thirty of these ants with several pupe and

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