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insects having four membranous wings, in which the nervures are small and scarcely conspicuous. This may startle those who are accustomed to consider ants as wingless creatures that burrow in little hillocks and under stones; but the discrepancy will disappear when it is stated that, like some other social insects, ants are of three sexes-males, females, and neuters--and that it is only the perfect sexes which are furnished with wings. The males and females form but a very small portion of established communities, and abound only for a short while before the swarming season in summer. At that time they go forth into the air, for the purposes of reproductionthe males dying in a few days, and the females falling to the ground, where they either return to the original nest, or are surrounded by stray neuters, and become the foundresses of new communities. They then throw off their wings as useless appendages, and become queens and mothers, in which state they never leave the nest, but are tended and fed by the neuters or workers. It is for this reason that the population of an ant-hill is so generally wingless, it being the neuters which form more than nine-tenths of the number, and on whom the labours and economy of the community entirely depend. They not only construct the nest, but most carefully tend the young grubs; supplying them with food, moving them on fine days to the outer surface of the nest, to give them heat, carrying them back again on the approach of night or bad weather, and defending them when attacked by enemies. The sexes are of different sizes, the females being largest, the neuters next, and then the males, which are
1. Female; 2. Male; 3. Worker. sometimes of very tiny proportions. Some of the neuters have longer bodies and larger heads than the others; and, as will be afterwards seen, these have peculiar functions assigned them in the labours of the community. Most of the species are stingless, but all of them bite fiercely with their mandibles, and have the property of ejecting a very acrid secretion, which inflames and irritates the skin like the sting of a nettle.
There are many species of ants, distinguished by their size and colour, but chiefly by their habits some burrowing in the ground, others piling up little mounds or hillocks; some hewing out their cells and passages in decayed timber, others constructing a nest of great neatness among the boughs and branches of the trees on which they feed. They are omnivorous in their habits—devouring almost any kind of vegetable or animal substance that lies within their reach; but are particularly fond of fruits, gums, and saccharine matter, and not less of
flesh, as may be seen by placing some small animal in their nests
, when, after a few days, its skeleton will be found as thoroughly cleaned as it could have been by the most skilful anatomist. It is generally believed, that in summer ants lay up a store of provision for their support during winter: this, however, is not the case in Europe, where they become dormant or torpid, and require no food." So far from their being partial to grain, it is a substance which, after protracted observation, we have seldom seen them touch, and assuredly none of their cells are constructed with the view of holding supplies. They are nurseries and dwelling apartments, not barns and storehouses. Any vegetable matter, therefore, which they may drag to their nest in summer, is either for present use, or to serve as an ingredient in constructing their habitation. In warm countries it is otherwise; the little creatures are ever active gathering their meat at all times, but more especially in summer and in harvest, when they find it most abundant. Paramount with the erection of their habitations, and the procuring of food, is the care which ants bestow on their young. Nor is it the temporary labour and assiduity of a few days, but frequently the toil and endurance of weeks and months.
The eggs produced by the queen-mother are at first so small, that they are hardly discernible to the naked eye; but when viewed through a microscope, they appear smooth, polished, and glossy. These minute granules are objects of great solicitude to the workers, who remove them, as soon as laid, to proper receptacles, and there nurse and tend them, moistening them with a peculiar liquid, and turning them by degrees, till they assume the larva form. In the larva and pupa state * they are nursed with still greater care. In cold weather, they are carried to the lowest retreats of the habitation, to secure them from the cold; and in fine weather, they are exposed to the genial influences of the
If an ant-hill be molested, the first care of the workers is to protect the young; and they may be seen running about in a state of distraction, each carrying a young one, frequently as big as itself. After remaining for some weeks as pupæ, the young burst the surrounding integument, and emerge in the adult form, and even then often receiving food from the older workers. The old ones, it is said, generally assist the young animal in freeing itself from confinement, by tearing with their mandibles the covering in which it is wrapped, as without such aid the young would frequently be unable to set itself at liberty. The pupæ are of a yellowish-white, and look like grains of corn, for which they were no doubt mistaken by early observers, who
* The terms Larva and Pupa are employed by naturalists to designate the intermediate states of existence in the insect, on its passage from the egg to its becoming a perfect animal, endowed with all the powers of its race-the former being commonly known under the appellation of Grub or Caterpillar, the latter of Chrysalis or Aurelia.
attributed to the ant the habit of storing up grain. It has been also gravely told that the insect bites off the growing end of the grain, to prevent it from sprouting-an act quite equal to human intelligence, but which is in reality nothing more than the creature’s habit of nibbling the envelope to set free the young. Ants swarm once or twice a-summer, when the young ones build new habitations for themselves, and live together in the same social and orderly manner as their progenitors.
These communities, as already stated, consist of males, females, and neuters. The females are the queen-mothers; but whether there is only one queen, as among bees, or several, is still a matter of doubt. Some naturalists affirm there is only one fertile female, and this may be the case in comparatively young swarms; but in old-established colonies, it is more than likely that there always exist a number of females of various ages. Be this as it may, the queens
have not the same omnipotent sway as among bees : ant-hives, are strictly republics, in which every member performs with honest cordiality the duty assigned him. The males are found in the nests only previous to swarming in summer, and are then equally, if not more numerous than the neuters. It is the latter which are the true republican workers : on them depend the erection of the habitation and its constant repair, the nursing and rearing of the young, the defence of the hive, and the col. lection of food. If nature has assigned to them the greater share of labour, she has also bequeathed a longer lease of enjoyment; for, after the winged males and females have left the hive in summer, a few days of aërial dalliance limits their existence. According to Gould, the ant remains in the larva state nearly a twelvemonth, in the state of pupa about six weeks, and as a perfect insect sixteen months. The time, however, they remain as larvæ and pupæ, is no doubt considerably influenced by variations of temperature and other causes. Thus, by exposure to sufficient warmth, the common white butterfly may be disclosed from its chrysalis in June, or it may be retarded till August by merely keeping it in a dark and colder situation. The lengthened period of perfect existence here spoken of refers strictly to the workers; the lives of the parent sexes are of very different duration.
Previous to the swarming season, the nests become crowded with young brood; the whole community is in a state of agitation-the winged males and females running and bustling among the wing less neuters. The wings of the former, which are exceedingly thin and fragile, soon attain their full size; and on the first favourable opportunity they take their departure from the parent hive. They do not seem to swarm simultaneously, but continue to make their egress by degrees, and as sunny weather presents itself. Once in the open air, the males do not return, like the drones or males of the honey-bee; and thus ants are not called upon to act the part of parricides and fratricides like bees, which invariably destroy their males in autumn. Though rarely or ever seen in the nests, at the swarming season winged ants sometimes appear in incredible numbers :-" In September 1814," says Dr Bromley,“ being on the deck of the hulk to the Clorinde (then in the river Medway), my attention was drawn to the water by the first lieutenant 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 bucketful 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.”' Purchas seems to have witnessed a similar phenomenon on shore. “ Other sorts of ants," says he,
“ there are many, of which some become winged, and fill the air with swarms, which sometimes happens in England. On Bartholomew 1613 I was in the island of Foulness, on our Essex shore, where were such clouds of these flying pismires, that we could nowhere flee from them, but they filled our clothes; yea, the floor of some houses where they fell, were in a manner covered with a black carpet of creeping ants; which they say drown themselves about that time of the year in the sea.” Many such clouds or swarms are noticed by other writers; and, allowing for a little exaggeration, it is quite impossible to conceive from whence they could have originated. Were all the ants of a district-males, females, and neuters--to be suddenly invested with wings, they could scarcely constitute such numbers; and one is almost tempted to the opinion, that at certain seasons all the sexes do in reality assume the winged form.
Thus much for the general characteristics of the fartily: we shall now advert to the habits and economy of our native species, borrowing our information chiefly from Gould, the younger Huber, and Latreille—the only authors who have made the ants of Europe objects of special observation.
Our native ants are usually distinguished by their colours and habits. Thus we have red, brown, and black ants; turf ants, hill ants, and wood ants--each species differing somewhat in size, colour, mode of obtaining food, and kind of habitation. The nest of the turf ant, which is one of the most common of our native species, is at once simple and ingenious. Sometimes it is formed under a flat stone, and consists simply of hollow cells and communicating galleries, all of which are excavated with great neatness, care being taken to remove the loose material to å distance from the nest. At other times it takes advantage of a tuft of grass, and piles around and amid the stems a considerable mound, the interior of which serves for a habitation—the stems giving it strength and coherence. The turf ant also delights in old earthen fences and hedge-banks which have a southern exposure. In these they excavate chamber upon chamber, and gallery after gallery : it is in such situations that we have found the most numerous colonies.
Other species, as the ash-coloured, brown, and yellow ants, construct little conical mounds, generally known as ant-hills; and this indeed is the most frequent kind of structure. These mounds are composed of pellets of moist earth found on the spot, and piled together with great architectural ingenuity, so as to form arched galleries, domes, pillars, and partitions, the whole being under one roof of compacted particles of earth and chips of grass and straw. “To form,” says M. Huber,“ a correct judgment of the interior arrangement or distribution of an ant-hill, it is necessary to select such as have not been accidentally spoiled, or whose form has not been too much altered by local circumstances; a slight attention will then suffice to show that the habitations of the different species are not all constructed after the same system. Thus, the hillock raised by the ash-coloured ants will always present thick walls, fabricated with coarse earth, well-marked storeys, and large chambers, with vaulted ceilings, resting upon a solid base. We never observe roads or galleries, properly so called, but large passages of an oval form, and all around considerable cavities and extensive embankments of earth. We further notice that the little architects observe a certain proportion between the large arched ceilings and the pillars that are to support them."
The brown ant, one of the smallest of our native species, is particularly remarkable for the extreme finish of its work. “It forms its nest of storeys four or five lines in height; the partitions are not more than half a line in thickness; and the substance of which they are composed is so finely-grained, that the inner walls present one smooth unbroken surface. These storeys are not horizontal; they follow the slope of the ant-hill, and lie one upon another to the ground-floor, which communicates with the subterranean lodges. They are not always, however, arranged with the same regularity, for these ants do not follow an invariable plan; it appears, on the contrary, that nature has allowed them a certain latitude in this respect, and that they can, according to circumstances, modify them to their wish; but however fantastical their habitations may appear, we always observe they have been formed by concentrical storeys. On examining each storey separately, we observe a number of cavities or halls, lodges of narrower dimensions, and long galleries, which serve for general communication. The arched ceilings covering the most spacious places, are supported either by little columns, slender walls, or by regular buttresses. We also notice chambers that have but one entrance, communicating with the lower storey, and large open spaces, serving as a kind of cross-road, in which all the streets terminate.