Fig. 334.—Cells from a Humble Bee's nest.Fig. 334.—Cells from a Humble Bee's nest.When the mother humble bee—which at first was alone and built her house single-handed—has made a certain number of cells, she seeks for honey and pollen, and prepares a paste, which she deposits in the future cradles. She then lays six or seven eggs in each. The larvæ which come from them live in common, at the same table, under the same tent. The cell is at first only the size of a pea; it soon becomes too narrow, splits and cracks, and requires to be enlarged and repaired many times, a work of which our industrious insects acquit themselves with a good deal of care and attention. Before passing into the pupa state each larva spins for itself a shell or cocoon of very fine white silk. It ceases to eat, remains at first rolled up, then expands itself little by little, and changes its skin after three days. It passes fifteen days in the pupa state in a quiescent condition. After the normal time has elapsed for it to remain in its hiding-place, it delivers itself from its mummy-like covering, with the help of the mother or the workers. The humble bee then appears, robust, and its body covered with a greyish down.When the successive hatchings have furnished to the mother the reinforcement she is waiting for, the workers she has raised occupy themselves in building new cells, and in raising the wall of enclosure which is to protect the nest. This wall, formed of wax, starts from the base, and raises itself, like a vertical rampart, from every point in the circumference. They then surmount this by the first roof, which is flat, supported by some pillars, and in which they have left one or two irregular openings. The whole is finally protected by a hemispherical covering of moss, made into a sort of felt and lined with wax.Fig. 335represents, in its entirety, a nest of this humble bee.Fig. 335.—Nest of the Moss Humble BeeFig. 335.—Nest of the Moss Humble Bee (Bombus muscorum).The workers also take their part in rearing the eggs. They bring the paste, which they slip into the cells to the larvæ by a small hole, which is shut immediately afterwards. Later, they again give their assistance in disengaging the pupæ from their envelopes. In short, they make themselves generally useful; but they have one bad fault: they are very fond of eating the eggs laid by the mother. They try to seize them as she deposits them, or drag them from the cells, and suck their contents. And so the mother is obliged to be incessantly defending her eggs against the voracity of the workers, and to be constantly on her guard, so as to be ready to drive away these marauders from cells newly filled.We owe to an English naturalist, Newport, the knowledge of another curious fact relating to the laying of humble bees, which is the expedient the females and the males have recourse to for hastening the hatching of the eggs. They place themselves, like fowls sitting on their eggs, over the cocoons containing the pupæ almost hatched. By breathing quickly, these industrious insects raise the temperature of their bodies, and consequently that of the air in the cells. Thanks to this supplementary heat, the metamorphosis of the pupæ is much hastened. Newport, by slipping miniature thermometers between the cocoons of the nymphs and the sitting humble bees, ascertained that the temperature of the latter was about 34° C., whilst the temperature of the cocoons left to themselves was only 27° C.; that of the air in the rest of the nest being only from 21° to 24° C. After many hours of incubation, at the same time natural and artificial, in which Art and Nature are so closely allied, after the sitting insects have many times relieved one another, the young humble bees come out of their cells. They are at first soft, greyish, moist, and very susceptible to cold. But after a few hours they become stronger, and the yellow and black bands with which their abdomens are surrounded begin to be marked out. The spring laying produces exclusively workers. The greatest abundance of eggs are laid in August and September. The laying of the female eggs begins in July; that of the males follows soon after.Until autumn the humble bees are incessantly enlarging their nests, and multiplying their little pots of honey. Without accumulating a great stock of provisions, for which they have no occasion, they always keep in reserve a quantity of pollen and honey for their daily wants. The cells in which the honey is stored differ very much in shape. Some species of humble bees give them long and narrow necks; others, lessrecherchéin their style of construction, simply make cylindrical vases. There are among the humble bees races of artists and races of simple builders; the one construct with taste, the other only seek the useful.During the day the humble bees cull honey from the flowers. At night they enter their home; but a certain number take the liberty of sleeping out. Surprised by the arrival of night in the bottom of the calyx of a sweetly-scented flower, they philosophically determine to sleep in the open air, lying on this perfumed bed, with the heaven as their canopy.The coupling of the humble bees takes place towards the end ofSeptember. It costs the males their life, as it does with the hive bees. The impregnated females do not lay till the following spring; it is they who, after the winter is passed, will become the mothers of new generations. They will take the reins of the family when the mother who founded the colony, the males, as also the workers, shall, according to the laws of Nature, have passed away. There are often, on the other hand, some workers which, born in the spring, become fruitful, and lay the same year, but only the eggs of males. These become a butt for the jealousy of the reigning mother, who pursues them with fury, and devours their eggs. These, however, have themselves cruel hearts. Animated by a profound jealousy, they dispute the occupancy of the cells savagely, so as to be able to lay a few eggs in them, which are no sooner laid than they are destroyed by their savage sisters. However, they never make use of their stings in any of these attacks. The humble bee population is peaceful, even in its combats. After the first cold weather in autumn, all these insects, as we have said, perish, except the pregnant females. These privileged depositaries of the race,spes altera domûs, look for a place of retreat, and there sleep till the following spring. Then they wake up and found new colonies, which continue the race.For a long while were confounded with the humble bees certain insects which have the same appearance, that is to say, a hairy body, with bands of various colours, but whose hind legs are adapted neither for gathering honey nor for building. These are the genusPsithyrus: it was Lepelletier de Saint-Fargeau who discovered their true position. These are parasites, and only consist of males and fertile females, without workers. They lay their eggs in the nest of the humble bee. They are, indeed, so like their hosts, that they can introduce themselves into their dwellings without raising any suspicion. The humble bees admit them freely, and receive them as if they belonged to the family; so much so, indeed, that the poor humble bees themselves bring up the larvæ of these impudent guests. In the Order Hymenoptera one meets with many examples of these sorts of parasites, which instal their progeny in the nest of another insect, as the cuckoo does in the nests of other birds.Solitary Bees.We have up till now found the insects of the great family of bees collected together in perfectly organised societies. But there are a great number of species of this family which live alone. We will briefly mention the most interesting of them.The females of the solitary bees are impregnated like those of the humble bees, and lay in spring, after having passed the winter asleep. They build a nest divided into cells, fill it with eggs, and with a honied paste shut it up, and die, without having seen their progeny hatched.Figs. 336, 337, 338.—Anthophora parietina.Fig. 339.—Carpenter Bee, Pupæ, Eggs, Galleries, and Nests.Fig. 339.—Carpenter Bee, Pupæ, Eggs, Galleries, and Nests.TheAnthophoras(Figs.336,337, 338) resemble bees, but they are more hairy, and of greyish colour. Their nest, composed of earth tempered and agglutinated with their saliva, is made in the cracks of old walls or in the ground. It has the form of a twisted tube, and is divided, by partitions, into compartments, each of which is to receive a larva. Each insect, when hatched, pierces its own wall, and profits by the hole of exit of the brother which preceded it.Fig. 340.—Mason Bee and Nest.These insects do not live together in societies. Indifferent neighbours, they do not lend each other mutual assistance. They have their parasites, theMelactas, like the humble bees. These parasites are hairy, blackish insects, spotted with white, laying their eggs in the nests of theAnthophoras, which permit them to do so, and, at the expense of their own progeny, bring up the intruder's little ones.The Carpenter Bee, or Wood-piercer (Xylocopa), hollows outgalleries in decayed wood, and builds in them cells placed one over the other—a work often occupying many weeks. She then furnishes the bottom of the cell with pollen mixed up with honey, lays an egg in the middle of this paste, and closes the cell by a ceiling of saw-dust agglutinated with saliva. On this ceiling she establishes a new cell, and so on, right up to the orifice, which she closes in the same manner. Réaumur is astonished, with reason, at the admirable instinct which makes this provident mother determine the exact quantity of nourishment which will be necessary for its larva. When this has absorbed all its provisions, it alone quite fills up its cell, and changes into a pupa. It is worthy of remark, that the head of the young is always turned downwards, in such a way that it is by the bottom of its cell that it comes out. The bottom of the first is very near the surface of the wood, so that the insect it encloses has only a thin layer of wood to pierce through in order to set itself free. Each one of those which are born next has only to pierce the floor of itshiding-place to find the road before it free. TheXylocopæpass the winter in the pupa state, and the perfect insects, with wings of a beautiful metallic violet, appear in the spring, but are not found in this country.Fig. 341.—Interior of the Nest of the Mason Bee.Other solitary bees have their hind legs unsuited for the gathering of pollen, but have the rings of the abdomen furnished with hairs for that purpose. Such are the Mason Bees of Réaumur, belonging to the generaOsmiaandChalicodoma,[98]which build their nests against walls with tempered earth, which become very hard.Fig. 342.—Rose Megachile (Megachile centuncularis).These nests (Figs.340and341) are filled with cells of oblong form arranged irregularly. At first sight they might be taken for little lumps of earth plastered against the wall. When the perfect insect emerges, it is obliged to soften the mortar with its saliva, and to remove it, grain by grain, with its mandibles. The nests ofChalicodomasare common in the environs of Paris, on walls of rough stones exposed to the south. They are often to be found in the parks of Meudon, of Conflans, of Vésinet, &c.The Leaf-cutting Bees (Megachile) are not less worthy of remark in their habits. These insects make their nests in tubes lined with the leaves of the rose, the willow, the lilac, &c., placed in a cylindrical burrow. Each nest contains generally from three to six cells, separated by partitions of leaves. They cut off the pieces of leaves they require with their mandibles, the notches being wonderfully cleanly cut, as if they had been done with a punch.Fig. 343.Gallery of anAndrena.They make as many as eight or ten envelopes in succession with the leaves, which, as they get dry, contract, keeping, however, the form given to them by the insect. The cells destined to receive the eggs acquire thus a certain solidity.Fig. 342represents the nest of the Megachile.The Upholsterer Bees (Anthocopas) line their nests with the petals of flowers, as, for example (Papaver rhæas), the corn-poppy. Their burrows are made perpendicularly in the beaten earth of roads, and each contains one solitary cell, lined with portions of petals. When the egg has been laid at the bottom of this cell, the bee fills up the rest of the hole with earth, to hide it from notice.The Mining Bees (Andrenæ) hollow out in the ground tubular galleries (Fig. 343). They are not larger than ordinary flies. A great number of other bees are known, but their habits are little understood, and we shall not occupy ourselves about them.Wasps.Every one knows the wasps as a race of dangerous brigands which live by rapine, are incessantly fighting battles, and which exist only todo harm. However, wasps, like Figaro, are better than they are reputed to be. Their societies are admirably organised; their nests are models of industry and artistic fancy. They have even certain domestic virtues which deserve our esteem; only they are an excitable race it is well not to cross. If great heat adds to their natural irritability, they savagely attack those who annoy them, and pursue them to a distance. No one, indeed, is ignorant that their sting is very painful. In cold weather, and towards night, they are less vivacious and less to be dreaded.Fig. 344.—Wasp's Nest.Fig. 344.—Wasp's Nest.The wasps are distinguished from the bees by a decided characteristic. In a state of repose they fold together their upper wings, which then seem very narrow, only spreading them out when they are about to fly; whilst the latter when at rest keep their upper wings spread out.Wasps live in companies, which last only a year, and are composed of males, females, and workers. But the female wasp does not pass her entire life in idleness as a queen, like the mother hive bee. She occupies herself in making the nest and in taking care of the young, like the mother humble bee. The males have also their duties. They watch over the cleanliness of the habitation, and are the sanitary commissioners and undertakers to the city. These are easily recognised by their oblong bodies, having so slight a connection with the thorax, as it were by a thread.Fig. 345.—Common Wasp (Vespa vulgaris).Fig. 346.—Bush Wasp (Vespa norvegica).Their sting is larger than that of the bees, and is supplied with poison from a pouch placed at its base. The males have no sting. Wasps do not secrete wax. With their mandibles they scrape wood and plants, the fragments of which they agglutinate together in such a way as to form a tough cardboard. Thus, they invented the manufacture of paper long before men. Charles de Geer, in his celebrated work, sums up the habits of these insects in the following manner:—"Wasps," says he, "are, like bees, fond of sweets and honey, although they rarely seek them in flowers; but their principal food consists in matters of quite a different kind, such as fruits of all kinds, raw flesh, and live insects, which they seize and devour. They sometimes do dreadful damage in bee-hives, devouring the honey, and killing the bees. They do not gather wax; their nests and their combs are composed of a matter resembling grey paper, which they get from rotten wood, and which they scrape off with their jaws; they make a sort of paste of these scrapings by moistening them with a certainliquid which they disgorge. The cells in the combs are hexagonal, and very regular, like those of bees."[99]Fig. 347.—The Hornet (Vespa crabro).Wasps collect the materials with which they build near the place where they have chosen to establish their domicile. These materials are ligneous fibre, mixed up with saliva, with the aid of which these insects prepare the paper-like substance, which is very tough, and destined to form the walls of the cells and their exterior covering. The greater number make their habitation in the ground. Of these is our Common Wasp (Vespa vulgaris), which is black, agreeably contrasted with bright yellow. The Bush Wasp (Vespa norvegica), which inhabits woods, constructs its nest between the branches of shrubs or bushes. It is smaller than the common species. The Hornet is the largest European species of the family of theVespidæ. The substance of its nest is yellowish, and very fragile, and is constructed under a roof, in a loft, or in the hole of an old wall, but most often in the hollow of a decayed tree. Another species of this family (Polistes gallica,Fig. 348) fixes its little nest by a footstalk to the stem of some plant.Fig. 348.—Polistes gallica.Wasps begin laying in spring, and go on laying all the summer. Each cell receives one single egg, and, as with bees, the workers' eggs are the first laid. Eight days after the laying, there comes out of each egg a larva without feet, and already provided with two mandibles. These larvæ receive their food in the form of balls, whichthe females or the workers knead up with their mandibles and their legs before presenting to their nurslings, very nearly in the same way as birds give their beak full of food to their little ones. At the end of three weeks the larvæ cease to take food, and begin to shut themselves up in their cells, the interior of which they line with a coating of silk. In this they change their form, and assume the appearance of the perfect insect, with its six legs and its wings, but motionless, and contracted together. A sort of bag keeps all the organs swathed up together (Fig. 349). This pupa state lasts for eight or nine days, at the end of which time the insect is fully developed; it casts its skin, breaks the door of its prison, and launches itself into the air. A cell is no sooner abandoned than a worker visits, cleans it, and puts it in a fit state to receive another egg.Fig. 349.Pupa of thecommon wasp.During the summer the female wasp remains constantly in the nest, absorbed with family cares. She is occupied in laying eggs and in feeding her progeny, with the active assistance of the workers, or mules, as Réaumur and Charles de Geer call them, because they are unfruitful.In the interior of the nests you generally find the most perfectly good understanding existing, and the most perfect order, in spite of the warlike instincts of these insects. It is only on rare occasions that this domestic peace is disturbed by the quarrels of male with male or worker with worker; but these combats are not deadly. Never, moreover, has one nest of wasps been known to declare war against another for the purpose of robbing it. "The government of wasps," says M. Victor Rendu, "explains very well the gentleness of their public conduct. Amongst them there are no despots; no one either reigns or governs; each one lives at liberty in a free city, on the sole condition of never being a burden to the state. They all act in concert, without privileges or monopolies, under the influence of a common law—the great law of the public good, from which no one is exempted."[100]But this model republic is fatally doomed to early destruction. At the approach of winter all the workers, as also the males, perish. Some pregnant females alone hold out against the cold, and get through the winter, to propagate and perpetuate their species. Before dying, these insects destroy all the larvæ which are not hatched at the first approach of cold weather. In spring the femalesrevive, and begin alone the construction of a new nest. They then lay workers' eggs, which are not long in furnishing them a whole regiment of devoted and active assistants. These traits are pretty nearly the same for the different species of wasps, the only difference being in the way in which they build their nests.Fig. 350.—Exterior of a Wasp's Nest on a branch of a tree.Fig. 350.—Exterior of a Wasp's Nest on a branch of a tree.We have already said that the common wasp makes its nest in the ground. A gallery, of about an inch and a half in diameter, leads to the nest, situated at a depth which varies from six inches to two feet. "It is," says Réaumur, "a small subterranean town, which is not built in the style of ours, but which has a symmetry of its own. The streets and the dwelling-places are regularly distributed. It is evensurrounded with walls on all sides. I do not give this name to the side of the hollow in which it is situated; the walls I allude to are only walls of paper, but strong enough, nevertheless, for the uses for which they are intended." Generally, the shape of the outside of a wasp's nest is spherical or oval, sometimes conical. Its diameter is about from twelve to sixteen inches, its surface, which resembles a mass of bivalve shells, has one hole for entrance, and another for exit, just large enough to allow of one single wasp passing in or out at the same time (Fig. 350).Fig. 351.—Interior of a Wasp's Nest, after Réaumur.Fig. 351.—Interior of a Wasp's Nest, after Réaumur.The wasps' nest is composed, in the interior, of fifteen or sixteen horizontal galleries, arranged in storeys, and supported by numerous pillars of separation. We give here (Fig. 351) a section and view ofthe interior, drawn from memory by Réaumur.[101]The cakes forming the combs are composed of hexagonal cells, which are always used as cradles, never as storehouses. They open below. The exterior envelope of the nest is made with leaves of a sort of greyish, very gummy paper, which is applied layer by layer. Réaumur has given a very detailed account of the way in which these insects construct their nests.[102]They collect fibres of wood—which are their raw material—make them into a sort of coarse lint, which they reduce to balls, and carry between their legs to the nest. These balls are next stuck on to the work already begun. Then the insect stretches them out, flattens them, and draws them into thin layers, as a bricklayer spreads mortar with his trowel. The wasp works with extreme quickness, always backwards, so that it may have incessantly before its eyes the work it has done: the movement of its mandibles is even quicker than that of its legs.Towards the end of summer the nest may contain 3,000 workers, and many females, who live together in perfect harmony. The number of males exceeds that of the females. A female weighs, by herself, as much as three males or six workers. With the exception of those which are occupied in building and in taking care of the eggs, all wasps go out hunting during the day. They are carnivorous, and may be seen attacking other insects, which they tear to pieces after having killed, so as to carry the bits to their nests, where thousands of mouths are clamouring for their food. The wasp pays great attention to the vines. It penetrates also into the interior of our houses, and infests the butchers' shops; but this the butchers do not much mind, for the wasp drives away the flies which would lay their eggs on the meat and thus contribute to its corruption.As the winter approaches, the wasps go out less and less, and very soon cease to do so at all. The greater number then die, huddled up in their nest. A few females only, as we have said, get through the cold season. They sleep with their wings and legs folded up, which gives them the appearance of chrysalides. They can nevertheless sting in this state, as M. Guérin-Méneville found out to his cost. The spring wakes them up, and they then found new colonies. "It is at this season," says M. Maurice Girard, in his book on the "Metamorphoses of Insects," "that, with a little trouble, it would be easy to diminish in a very perceptible degree the number of wasps, which are, later, so destructive to the fruit, by catching innets the females, which might be attracted in quantities by means of the blossom of the black currant." This is a useful hint to gardeners.The Hornets are distinguished from other wasps by their great size. They make their nests in the trunks of old trees, perforating the sound wood to arrive at the heart, which is rotten, or hollowing for themselves a hole, which they clear out by the gallery which leads to it. In this hole they construct first a dome suspended to the top by a footstalk; then a series of combs composed of cells, hanging the first to this dome, the second to the first, and so on, by stalks or pillars of a paper-like substance. When fixed under roofs, these insects have often the form of an elongated pear.Fig. 352represents one of these nests, after Réaumur. The societies of hornets contain fewer members than those of the common wasp; at most 200 insects.Fig. 352.—Hanging Hornet's Nest.Fig. 352.—Hanging Hornet's Nest.ThePolistesare a peculiar kind of wasp, smaller than the others, slender, with the abdomen tapering towards the base. The construction of their nests is more simple, having no envelopes, as shown inFig. 353. They attach them to the stems of broom, furze, or other shrubs, by a footstalk, or pedicle. They are like littlepaper bouquets, composed of from twenty to thirty cells, grouped in circle.Fig. 353.—Nest ofPolistes gallica.Fig. 354.—The Card-making WaspFig. 354.The Card-making Wasp(Chartergus nidulans).The Card-making Wasp of Cayenne (Chartergus nidulans,Fig. 354) is a consummate artist. Its nest represents a sort of box or bag, made of a substance resembling cardboard, so fine and so white that the best worker in that material would be deceived by it. This nest has only one single hole at its base; each of the combs it contains is likewise pierced by a hole in its centre, to afford a passage to the wasps. In an architectural point of view, the card-making wasp is almost superior to the bee, for the latter does notbuildits house, it onlyfurnishesit, as Latreille remarks with truth. The Brazilian species ofChartergus, which the inhabitants call Lecheguana,[103]manufactures a honey, the use of which is not without danger, as it occasions vertigo and sharp pains in the stomach. The naturalist, Auguste Saint-Hilaire, during his sojourn in Brazil, himself experienced ill effects from eating it.There are, moreover, solitary wasps, which make their cells in holes which they scoop out in the ground, or in the stalks of certain plants. In the adult state these live on honey; but their larvæ are carnivorous, and the female is obliged to bring them living insects. The commonest of these solitary wasps belong to the genusOdynerus.This insect makes its nest in the stalk of a bramble or briar (Fig. 358) with a mortar which it prepares. The larva (Fig. 356) lines its cell with a silky cocoon. It is the last egg laid which is hatched the first; then come the others, in an inverse order from that in which they were deposited. If it had been in the other order, the insects could not have come out of the cells without destroying on their way the less advanced pupa.Fig. 355.—A species of Odynerus.Fig. 356.—Larva of the Odynerus.Fig. 357.—Pupa of the Odynerus.Fig. 358.—Nest of an Odynerus in the stem of a bramble.Ants.The habits of the Ants are as remarkable as the habits of the bees. In their marvellous republics each one has his fixed duties to perform, of which he acquits himself willingly and without constraint. In consequence of their habits of foresight and frugality, ease reigns in the dwellings of these little animals, which become attached to their nest by a feeling of patriotism. Woe betide him who disturbs them in their occupations, or destroys their house! Like bees, they form a regular republic, composed—first, of males; secondly, of females; thirdly of neuters, or workers. We shall see, further on, the labours and the part played by each one of these three orders of the republic. Let us speak first of the species.Ants are divided into a great number of species, which have been carefully described by De Geer, Latreille, and Francis Huber, the son of the celebrated blind man who wrote the history of bees. All these species have, however, some general traits in common, by which they may be easily distinguished from all other insects. Ants have a slim body on long legs. The workers are stouter and smaller than the males; and these last are smaller than the females. The males have large and prominent eyes, whilst the eyes of the workers and females are small.Fig. 360.—Brazilian Umbrella Ant.Fig. 359.—Red Ant. Male magnified.(Myrmica rubra.)Fig. 360.—Brazilian Umbrella Ant.(Atla cephalotes.)Ants are provided with antennæ, bent in the form of an elbow, with which they examine everything they meet, and which seem to assist them in the communication of their ideas. Two horny, very strong mandibles serve them at the same time as pincers, tweezers, scissors, pick-axe, fork, and sword. A thin short neck joins the head to the thorax, to which, in the case of the males and females, are attached four large veiny wings. The workers only have no wings. Of the three pairs of legs, the hind ones are the longest. Each pair is armed with a spur, and fringed with very short hairs, which serve the purpose of brushes. The abdomen, large, short, oval, or square, is always most voluminous in the females.There are three genera of ants which we shall mention. TheMyrmicæhave two knobs to the pedicle, by which the abdomen is attached to the thorax; thePoneræonly one. In these two genera, the females and the neuters have a sting, and the larvæ do not spin a cocoon in which to change into pupa. Lastly, theFormicæ—ants properly so called—have but one knob on the pedicle of theabdomen, as inPonera; their larvæ spin a silky cocoon. They have no sting, but they pour into the wounds made by their mandibles an acid liquor, the pungent smell of which is well known. This liquid is formic acid, a natural product, which the chemist now-a-days knows how to make artificially, by the action of dilute sulphuric acid on maize and other vegetable matters. Their whole body is impregnated with this acid, and has a strong sour smell. Some people like to chew ants, on account of their sourish taste. "They also make," says Charles de Geer, "creams for side-dishes, to which these ants give, they say, the taste of lemon-juice." We know, in the south of France, people who have eaten thesecrèmes aux fourmis!Polyergusforms a sub-genus ofFormica.Fig. 361.—Sections of an Ant's Nest.Fig. 361.—Sections of an Ant's Nest.In all these species, the workers, or neuters, have the charge ofthe building, provisioning, and rearing of the larvæ—in fact, all the care of the household, and the defence of the nest. Deprived of wings, they are bound to the soil, and condemned to work. As compensation, to them belong strength, authority, power: nothing is done but through them. "Born protectors of an immense family still in the cradle," says M. Victor Rendu, "by their vigilance, their tenderness, and their solicitude, without being mothers themselves, they share in the duties and joy of maternity. Alone, they decide on peace or war; alone, they take part in combats: head, heart, and arm of the republic, they ensure its prosperity, watch over its defence, found colonies, and in their works show themselves great and persevering artists."The nests of ants (Figs.361,362) are known under the name of ant-hills. They vary very much, both as to their form and the materials employed in making them—wood and earth are the principal. That which strikes one at first sight, is the size of these dwellings, which form a curious contrast to the smallness of their builders. Each species of ant has an order of architecture peculiar to it. The Red Ant (Formica rufa), one of the commonest in our woods, constructs a little rounded hillock with all kinds of objects—fragments of wood, bits of straw, dry leaves, the remains of insects, &c. This hillock, the base of which is protected by material of greater solidity, is nothing more than the exterior envelope of the nest, which is carried underground to a very great depth. Avenues, cleverly contrived, lead from the summit to the interior. The openings vary in width; and, as night approaches, are carefully barricaded. They are opened every morning, except on rainy days, when the doors remain shut, and the inhabitants confined within.The ant-hill, orformicarium, is at first simply a hole hollowed out in the soil, the entrance to which is masked by the building materials. But the miners do not cease to hollow out galleries and chambers, arranged by stories. The earth and rubbish are carried out, and serve to construct the upper edifice, which rises at the same time that the excavation grows deeper. It is a labyrinth bored in all directions. It contains corridors, landings, chambers, and spacious rooms, which communicate with each other by passages which are often vertical. All the corridors lead to a large central space, loftier than the others, and supported by pillars; it is here that the greater number of the ants congregate. These ant-hills often rise to a height of fifteen inches above the ground, and descend to an equal depth.Fig. 362shows the interior of an ant-hill, drawn from Nature. Outside it are to be seen some ants occupied in sucking plant-lice.Fig. 362.—Section of an Ant-hill.Fig. 362.—Section of an Ant-hill.The group of Mason Ants contains a great number of varieties: the Ashy-black Ant (Formica nigra,Fig. 363), the Brown, the Yellow (Formica flava), the Blood-red, the Russety (Polyergus rufescens), the Black, the Miner (Formica cunicularia), the Turf Ant, &c. All these species employ a mortar, more or less fine, in raising their hillocks, at the same time that they hollow out their underground dwellings. The Jet Ant (Formica fuliginosa) excavates wood, hollowing out its labyrinth in the trunk of a tree with consummate skill. The Red Ant (Myrmica rubra) plies, according to circumstances, the trade of a mason or excavator.Fig. 363.—Ashy-black AntFig. 363.—Ashy-black Ant (Formica nigra). Male, female, and worker.The masons work when they can profit by the rain or by the evening dew, to make their mortar. They only go out after sunset, or when a fine rain has wetted their roof. Then they set to work. They roll up pellets of earth, bring them back in their mandibles, and stick them on to those places where the building was left unfinished. From all sides the earth-workers may be seen arriving, laden with materials. All these are bustling, hurrying, busy, but always in the greatest order, and with a perfect understanding among themselves. Every part of the building is going on at the same time. The apartments spring up one above another, and the edifice visibly rises. The rain, the sun, and the wind consolidate and harden the building socunningly contrived by these industrious workers, who have received from God alone their marvellous science. With no other tool than their mandibles, the excavators work their way through the hardest wood. They bore holes right through it, riddling it completely with numerous storeys of horizontal galleries. The Yellow Ant raises its little hillocks in fields, and passes the winter in a burrow or underground dwelling-place.Fig. 364.—Ashy Ant. Male, worker, and female.Fig. 364.—Ashy Ant. Male, worker, and female.Independent of the principal entrances, there exist, in some nests, masked doors guarded by sentinels. Many species also hollow out covered galleries, which they only unmask in extreme danger, either to open an outlet for the besieged, or to turn the enemy who has already invaded the place. Ant-hills are, in fact, perfect fortresses, defended by a thousand ingenious contrivances, and guarded by sentinels always on thequi vive.Fig. 365.—Larva of the Red Ant.(Myrmica rubra).Fig. 366.—Pupa of the Red Ant(Myrmica rubra) magnified.The domestic life of the different species is nearly the same. The birth and rearing of the little ones, and the duties of the adults, do not differ perceptibly from each other in the various species of ants. The females live together in harmony. They lay, without ceasing to walk about, white eggs of cylindrical form and microscopic dimensions. The workers pick them up, and carry them to special chambers. In a fortnight after the laying, the larva (Fig. 365) appears. Its body is transparent. A head and wings can be made out, but no legs; the mouth is a retractile nipple, bordered by rudimentary mandibles, into which the workers disgorge the juices they have elaborated in their stomachs; and as they lay by no provisions,they are obliged to gather each day the sugary liquids destined for the food of the larvæ.From their birth, a troop of nurses is charged with the care of them. They put them out in the open air during the day. Hardly has the sun risen, when the ants, placed just under the roof, go to tell those which are beneath, by touching them with their antennæ, or shaking them with their mandibles. In a few seconds, all the outlets are crowded with workers carrying out the larvæ in order to place them on the top of the ant-hill, that they may be exposed to the beneficent heat of sun. When the larvæ have remained some time in the same place, their guardians move them away from the direct action of the solar rays, and put them in chambers a little way from the top of the hill, where a milder heat can still reach them. We then see the ants themselves taking the well-earned luxury of a few minutes' rest, heaping themselves up together, right in the sun. There is no observant inhabitant of the country who has not seen the curious spectacle which we have just mentioned—that is to say, the population of an ants' nest carrying into the sun the young nurslings, so that they may experience the action of the solar heat. We recommend the dweller in towns who is in the country for a day to stretch himself out near an ant-hill in the warm weather, and witness this spectacle, one of the most curious in Nature. The care which the working ants bestow on their young does not consist only in nourishing them and procuring for them a proper temperature; they have also to keep them extremely clean. With their palpi they clean them, brush them, distend their skin, and thus prepare them for the critical trial of their metamorphosis.At this moment the larvæ of ants, properly so called, spin themselves a silky cocoon, of a close tissue and of a grey or yellowish colour; those of theMyrmicæand of thePonerædo not surround themselves with a silky cocoon before changing into pupæ. These are at first of a pure white, but they very soon assume a brown colour, which increases until it becomes dark brown. They possess all the organs of the adult, enveloped in a membrane so thin that it seems to be iridescent.Fig. 366represents the pupa of the red ant. They are the cocoons enclosing the pupæ, which are incorrectly called in the country ants' eggs, and are given to young pheasants and partridges. The pupæ remain motionless till the insects emerge, which is accomplished with the assistance of the workers. These latter tear the covering from the pupa, and complete its deliverance. They then watch over the newly-born ant. For some days they feed it, help it to walk, and do not abandon it till it can dispense with their good offices. These workers, when provisions fail, or when the ant-hill is threatened with any great danger, take in their mandibles the eggs, the larvæ, the pupæ, and sometimes those females and the males which refuse to follow them. Thus laden, they go their way, to seek for another country they may call their own. They never forget, in their hurried emigrations, the infirm or sick workers, which would perish in the house now abandoned and deserted.The males and females lately hatched do not enjoy the same liberty as the young workers. They are confined to the ant-hill, where they are kept in sight till the day of the general departure. It is towards the end of the month of August that swarms of winged ants of both sexes are seen to issue forth. The males come out first, agitating their iridescent and transparent wings. The females, less numerous, follow them closely. All of a sudden one sees this troop raise itself at a given signal, and disappear in the air, where the coupling takes place. The males perish immediately afterwards. The females impregnated return to the paternal home, or else found new colonies with the assistance of a few workers who are their escort. From this moment they no longer require wings. The workers make haste to cut them off, or, indeed, which oftenest happens, they themselves tear them off. With their wings they lose the desire for liberty. Henceforward, they will quit their retreat no more, the cares of their approaching maternity now alone occupying them. The working ants reserve for them subterranean chambers, where they are kept in sight by the sentinels. At certain hours only are they to be met with in the upper storeys. When they wish to walk, a company of guards presses round them on all sides so as to prevent them from advancing too quickly. There are no sorts of attentions they do not heap upon them to make them forget their captivity. They caress them, brush them, lick them, they offer them food continually. On the least appearance of danger, the workers take possession, first of all, of the pregnant females, and drag them out by the secret outlets, so as to put in a place of safety their precious persons, the hope of the community. The workers' task is immense, for their labours increase in the same proportion as the population increases. But the division of work and the good understanding which exists between the members of the community, allow them to be prepared for anything that may happen, and to supply all their necessities.Nothing is more amusing than to observe the shifts ants are put to in transporting objects of great size. They stumble, they tumble head over heels, they roll down precipices; but, in spite of all accidents, return to their task, and always accomplish it.The tranquil inhabitants of these subterranean republics are bound together by mutual affection in a devoted fraternity, which makes them ever ready to assist each other. They all help one another as much as they can. If an ant is tired, a comrade carries it on its back. Those which are so absorbed with their work that they have no time to think of their food, are fed by their companions. When an ant is wounded, the first one who meets it renders it assistance, and carries it home. Latreille having torn the antennæ from an ant, saw another approach the poor wounded one, and pour, with its tongue, a few drops of a yellow liquid on the bleeding wound.Huber the younger one day took an ant's nest to populate one of those glass contrivances which he used for making his observations, and which consisted of a sort of glass bell placed over the nest. Our naturalist set at liberty one part of the ants, which fixed themselves at the foot of a neighbouring chestnut tree. The rest were kept during four months in the apparatus, and at the end of this time Huber moved the whole into the garden, and a few ants managed to escape. Having met their old companions, who still lived at the foot of the chestnut tree, theyrecognisedthem. They were seen, in fact, all of them, to gesticulate, to caress each other mutually with their antennæ, to take each other by the mandibles, as if to embrace in token of joy, and they then re-entered together the nest at the foot of the chestnut tree. Very soon they came in a crowd to look for the other ants under the bell, and in a few hours our observer's apparatus was completely evacuated by its prisoners. When an ant has discovered any rich prey, far from enjoying it alone, like a gourmand, it invites all its companions to the feast. Community of goods and interests exists amongst all the members of this model society. It is the practical realisation of the dream formed by certain philosophers of our day, who were only able to conceive the idea, the possibility, the project of such a community of goods and interests, which is among ants a reality.How do these insects manage to make themselves understood in such various ways, asking for help, giving advice, giving invitations? They must have a language of their own, or else they must communicate their impressions by the play of their antennæ.When an ant is hungry, and does not wish to disturb itself from its work, it tells a foraging ant as it passes, by touching it with its antennæ; the latter approaches it immediately, and presents it, on the end of its tongue, some juice it has disgorged for this purpose. The antennæ, then, are used by the ants for the purpose of making themselves understood by each other. Dr. Ebrard, who studied theseinsects attentively, is of opinion that they use them in the same way as a blind man does his stick, to feel their way with, for their sight is not good. The age to which ants live is not well known. It is believed that the workers live many years.Ants eat all sorts of things. One sees them eating fresh or decaying meat, fruits, flowers, particularly everything which is sugary. They attack living insects, and kill them and suck their blood. Like many insects, they are very fond of sugary liquids—honey, syrups, pure sugar, &c. Dupont de Nemours relates in his Memoirs that, to guarantee his sugar-basin against the invasion of ants, he had found no better plan than to make it "an island," that is to say, to place it in the middle of a vessel full of water. He felt sure that he had made the fortress safe against any attack; but listen to the stratagem made use of by the besiegers. The ants climbed up the wall to the ceiling, exactly perpendicularly over the sugar-basin. From there they let themselves fall into the interior of the place, penetrating thus by main force, and without injuring any one, into the magazine. As the ceiling was very high, the draught caused them to deviate from the straight line, and thus a certain number fell into the fosse of the citadel, that is to say, into the water in the vessel. Their companions stationed on the bank made all efforts imaginable to fish out the drowning ants, but were afraid of taking to the water of such a large lake. All that they could do was to stretch out their bodies as far as possible (keeping on the bank the while), to lend a helping hand to their drowning friends. Nevertheless, the salvage did not progress much; when the ants, which were getting very uneasy, conceived a happy thought. A few were seen to run to the ant-hill, and then to reappear. They brought with them a squad of eight grenadiers, who threw themselves into the water without any hesitation, and who, swimming vigorously, seized with their pincers all the drowning ants, and brought them all on toterra firma. Eleven, half-dead, were thus brought to shore, that is, to the rim of the basin. They would probably all of them have succumbed, if their companions had not hastened to lend them assistance. They rolled them in the dust, they brushed them, they rubbed them, they stretched themselves on their dying companions to warm them; then they rolled them and rubbed them again. Four were restored to life. A fifth half recovered, and, still moving its legs and its antennæ a little, was taken home with all sorts of precautions. The six others were dead. They were carried into the ant-hill by their afflicted companions. It seems like a dream to read such things as this, and yet Dupont de Nemours tells us, "I have seen it!"Ants are also very fond of a peculiar liquid which the plant-lice secrete from a pouch in the abdomen. When they have got possession of a plant-louse, they excite it to secrete this liquid, but without doing it any harm. They carry the plant-lice into the ant-hill, or into private stables. There they keep them, give them their food, and suck them. We have already mentioned these curious relations which are established between ants and plant-lice.[104]Fig. 367 shows an ant thus occupied. TheGallinsectaalso furnish the ants with sugary liquids.During the cold of winter the ants sleep at the bottom of their nests, without taking any food. A small number of species only hold out through the severe season, by shutting themselves up in the ant-hill with a number of plant-lice. It is thus that they pass the winter with a supply of food. We must mention, however, that in warm countries the ants do not hybernate.We have just described ant society during the quiet periods, when peace reigns supreme; but they are not more exempt than other animals from the necessities and dangers of war. They have a great many enemies among the population of the woods; they must, then, be prepared to repel their attacks. They display in that the most scientific resources of the military art applied to defence.It is almost needless to say that the sentinels are, at all times, posted at a reasonable distance from the ant-hill, to observe the environs. When the fortress is unexpectedly attacked, whether by large insects, Coleoptera for instance, or by the ants from a neighbouring nest, these vigilant sentinels immediately fall back and give the alarm to the camp, not, however, without having boldly confronted the enemy and opposed to him an honourable resistance. Having re-entered the nest in all haste, they precipitate themselves into the passages, tapping with their antennæ all the ants which they meet, and thus spreading the alarm in the city. Very soon the agitation has become general, and thousands of combatants sally forth from the citadel, ready to repel the attack and make the enemy bite the dust.
Fig. 334.—Cells from a Humble Bee's nest.Fig. 334.—Cells from a Humble Bee's nest.
When the mother humble bee—which at first was alone and built her house single-handed—has made a certain number of cells, she seeks for honey and pollen, and prepares a paste, which she deposits in the future cradles. She then lays six or seven eggs in each. The larvæ which come from them live in common, at the same table, under the same tent. The cell is at first only the size of a pea; it soon becomes too narrow, splits and cracks, and requires to be enlarged and repaired many times, a work of which our industrious insects acquit themselves with a good deal of care and attention. Before passing into the pupa state each larva spins for itself a shell or cocoon of very fine white silk. It ceases to eat, remains at first rolled up, then expands itself little by little, and changes its skin after three days. It passes fifteen days in the pupa state in a quiescent condition. After the normal time has elapsed for it to remain in its hiding-place, it delivers itself from its mummy-like covering, with the help of the mother or the workers. The humble bee then appears, robust, and its body covered with a greyish down.
When the successive hatchings have furnished to the mother the reinforcement she is waiting for, the workers she has raised occupy themselves in building new cells, and in raising the wall of enclosure which is to protect the nest. This wall, formed of wax, starts from the base, and raises itself, like a vertical rampart, from every point in the circumference. They then surmount this by the first roof, which is flat, supported by some pillars, and in which they have left one or two irregular openings. The whole is finally protected by a hemispherical covering of moss, made into a sort of felt and lined with wax.Fig. 335represents, in its entirety, a nest of this humble bee.
Fig. 335.—Nest of the Moss Humble BeeFig. 335.—Nest of the Moss Humble Bee (Bombus muscorum).
The workers also take their part in rearing the eggs. They bring the paste, which they slip into the cells to the larvæ by a small hole, which is shut immediately afterwards. Later, they again give their assistance in disengaging the pupæ from their envelopes. In short, they make themselves generally useful; but they have one bad fault: they are very fond of eating the eggs laid by the mother. They try to seize them as she deposits them, or drag them from the cells, and suck their contents. And so the mother is obliged to be incessantly defending her eggs against the voracity of the workers, and to be constantly on her guard, so as to be ready to drive away these marauders from cells newly filled.
We owe to an English naturalist, Newport, the knowledge of another curious fact relating to the laying of humble bees, which is the expedient the females and the males have recourse to for hastening the hatching of the eggs. They place themselves, like fowls sitting on their eggs, over the cocoons containing the pupæ almost hatched. By breathing quickly, these industrious insects raise the temperature of their bodies, and consequently that of the air in the cells. Thanks to this supplementary heat, the metamorphosis of the pupæ is much hastened. Newport, by slipping miniature thermometers between the cocoons of the nymphs and the sitting humble bees, ascertained that the temperature of the latter was about 34° C., whilst the temperature of the cocoons left to themselves was only 27° C.; that of the air in the rest of the nest being only from 21° to 24° C. After many hours of incubation, at the same time natural and artificial, in which Art and Nature are so closely allied, after the sitting insects have many times relieved one another, the young humble bees come out of their cells. They are at first soft, greyish, moist, and very susceptible to cold. But after a few hours they become stronger, and the yellow and black bands with which their abdomens are surrounded begin to be marked out. The spring laying produces exclusively workers. The greatest abundance of eggs are laid in August and September. The laying of the female eggs begins in July; that of the males follows soon after.
Until autumn the humble bees are incessantly enlarging their nests, and multiplying their little pots of honey. Without accumulating a great stock of provisions, for which they have no occasion, they always keep in reserve a quantity of pollen and honey for their daily wants. The cells in which the honey is stored differ very much in shape. Some species of humble bees give them long and narrow necks; others, lessrecherchéin their style of construction, simply make cylindrical vases. There are among the humble bees races of artists and races of simple builders; the one construct with taste, the other only seek the useful.
During the day the humble bees cull honey from the flowers. At night they enter their home; but a certain number take the liberty of sleeping out. Surprised by the arrival of night in the bottom of the calyx of a sweetly-scented flower, they philosophically determine to sleep in the open air, lying on this perfumed bed, with the heaven as their canopy.
The coupling of the humble bees takes place towards the end ofSeptember. It costs the males their life, as it does with the hive bees. The impregnated females do not lay till the following spring; it is they who, after the winter is passed, will become the mothers of new generations. They will take the reins of the family when the mother who founded the colony, the males, as also the workers, shall, according to the laws of Nature, have passed away. There are often, on the other hand, some workers which, born in the spring, become fruitful, and lay the same year, but only the eggs of males. These become a butt for the jealousy of the reigning mother, who pursues them with fury, and devours their eggs. These, however, have themselves cruel hearts. Animated by a profound jealousy, they dispute the occupancy of the cells savagely, so as to be able to lay a few eggs in them, which are no sooner laid than they are destroyed by their savage sisters. However, they never make use of their stings in any of these attacks. The humble bee population is peaceful, even in its combats. After the first cold weather in autumn, all these insects, as we have said, perish, except the pregnant females. These privileged depositaries of the race,spes altera domûs, look for a place of retreat, and there sleep till the following spring. Then they wake up and found new colonies, which continue the race.
For a long while were confounded with the humble bees certain insects which have the same appearance, that is to say, a hairy body, with bands of various colours, but whose hind legs are adapted neither for gathering honey nor for building. These are the genusPsithyrus: it was Lepelletier de Saint-Fargeau who discovered their true position. These are parasites, and only consist of males and fertile females, without workers. They lay their eggs in the nest of the humble bee. They are, indeed, so like their hosts, that they can introduce themselves into their dwellings without raising any suspicion. The humble bees admit them freely, and receive them as if they belonged to the family; so much so, indeed, that the poor humble bees themselves bring up the larvæ of these impudent guests. In the Order Hymenoptera one meets with many examples of these sorts of parasites, which instal their progeny in the nest of another insect, as the cuckoo does in the nests of other birds.
Solitary Bees.
We have up till now found the insects of the great family of bees collected together in perfectly organised societies. But there are a great number of species of this family which live alone. We will briefly mention the most interesting of them.
The females of the solitary bees are impregnated like those of the humble bees, and lay in spring, after having passed the winter asleep. They build a nest divided into cells, fill it with eggs, and with a honied paste shut it up, and die, without having seen their progeny hatched.
Figs. 336, 337, 338.—Anthophora parietina.
Fig. 339.—Carpenter Bee, Pupæ, Eggs, Galleries, and Nests.Fig. 339.—Carpenter Bee, Pupæ, Eggs, Galleries, and Nests.
TheAnthophoras(Figs.336,337, 338) resemble bees, but they are more hairy, and of greyish colour. Their nest, composed of earth tempered and agglutinated with their saliva, is made in the cracks of old walls or in the ground. It has the form of a twisted tube, and is divided, by partitions, into compartments, each of which is to receive a larva. Each insect, when hatched, pierces its own wall, and profits by the hole of exit of the brother which preceded it.
Fig. 340.—Mason Bee and Nest.
These insects do not live together in societies. Indifferent neighbours, they do not lend each other mutual assistance. They have their parasites, theMelactas, like the humble bees. These parasites are hairy, blackish insects, spotted with white, laying their eggs in the nests of theAnthophoras, which permit them to do so, and, at the expense of their own progeny, bring up the intruder's little ones.
The Carpenter Bee, or Wood-piercer (Xylocopa), hollows outgalleries in decayed wood, and builds in them cells placed one over the other—a work often occupying many weeks. She then furnishes the bottom of the cell with pollen mixed up with honey, lays an egg in the middle of this paste, and closes the cell by a ceiling of saw-dust agglutinated with saliva. On this ceiling she establishes a new cell, and so on, right up to the orifice, which she closes in the same manner. Réaumur is astonished, with reason, at the admirable instinct which makes this provident mother determine the exact quantity of nourishment which will be necessary for its larva. When this has absorbed all its provisions, it alone quite fills up its cell, and changes into a pupa. It is worthy of remark, that the head of the young is always turned downwards, in such a way that it is by the bottom of its cell that it comes out. The bottom of the first is very near the surface of the wood, so that the insect it encloses has only a thin layer of wood to pierce through in order to set itself free. Each one of those which are born next has only to pierce the floor of itshiding-place to find the road before it free. TheXylocopæpass the winter in the pupa state, and the perfect insects, with wings of a beautiful metallic violet, appear in the spring, but are not found in this country.
Fig. 341.—Interior of the Nest of the Mason Bee.
Other solitary bees have their hind legs unsuited for the gathering of pollen, but have the rings of the abdomen furnished with hairs for that purpose. Such are the Mason Bees of Réaumur, belonging to the generaOsmiaandChalicodoma,[98]which build their nests against walls with tempered earth, which become very hard.
Fig. 342.—Rose Megachile (Megachile centuncularis).
These nests (Figs.340and341) are filled with cells of oblong form arranged irregularly. At first sight they might be taken for little lumps of earth plastered against the wall. When the perfect insect emerges, it is obliged to soften the mortar with its saliva, and to remove it, grain by grain, with its mandibles. The nests ofChalicodomasare common in the environs of Paris, on walls of rough stones exposed to the south. They are often to be found in the parks of Meudon, of Conflans, of Vésinet, &c.
The Leaf-cutting Bees (Megachile) are not less worthy of remark in their habits. These insects make their nests in tubes lined with the leaves of the rose, the willow, the lilac, &c., placed in a cylindrical burrow. Each nest contains generally from three to six cells, separated by partitions of leaves. They cut off the pieces of leaves they require with their mandibles, the notches being wonderfully cleanly cut, as if they had been done with a punch.
Fig. 343.Gallery of anAndrena.
They make as many as eight or ten envelopes in succession with the leaves, which, as they get dry, contract, keeping, however, the form given to them by the insect. The cells destined to receive the eggs acquire thus a certain solidity.Fig. 342represents the nest of the Megachile.
The Upholsterer Bees (Anthocopas) line their nests with the petals of flowers, as, for example (Papaver rhæas), the corn-poppy. Their burrows are made perpendicularly in the beaten earth of roads, and each contains one solitary cell, lined with portions of petals. When the egg has been laid at the bottom of this cell, the bee fills up the rest of the hole with earth, to hide it from notice.
The Mining Bees (Andrenæ) hollow out in the ground tubular galleries (Fig. 343). They are not larger than ordinary flies. A great number of other bees are known, but their habits are little understood, and we shall not occupy ourselves about them.
Wasps.
Every one knows the wasps as a race of dangerous brigands which live by rapine, are incessantly fighting battles, and which exist only todo harm. However, wasps, like Figaro, are better than they are reputed to be. Their societies are admirably organised; their nests are models of industry and artistic fancy. They have even certain domestic virtues which deserve our esteem; only they are an excitable race it is well not to cross. If great heat adds to their natural irritability, they savagely attack those who annoy them, and pursue them to a distance. No one, indeed, is ignorant that their sting is very painful. In cold weather, and towards night, they are less vivacious and less to be dreaded.
Fig. 344.—Wasp's Nest.Fig. 344.—Wasp's Nest.
The wasps are distinguished from the bees by a decided characteristic. In a state of repose they fold together their upper wings, which then seem very narrow, only spreading them out when they are about to fly; whilst the latter when at rest keep their upper wings spread out.
Wasps live in companies, which last only a year, and are composed of males, females, and workers. But the female wasp does not pass her entire life in idleness as a queen, like the mother hive bee. She occupies herself in making the nest and in taking care of the young, like the mother humble bee. The males have also their duties. They watch over the cleanliness of the habitation, and are the sanitary commissioners and undertakers to the city. These are easily recognised by their oblong bodies, having so slight a connection with the thorax, as it were by a thread.
Their sting is larger than that of the bees, and is supplied with poison from a pouch placed at its base. The males have no sting. Wasps do not secrete wax. With their mandibles they scrape wood and plants, the fragments of which they agglutinate together in such a way as to form a tough cardboard. Thus, they invented the manufacture of paper long before men. Charles de Geer, in his celebrated work, sums up the habits of these insects in the following manner:—"Wasps," says he, "are, like bees, fond of sweets and honey, although they rarely seek them in flowers; but their principal food consists in matters of quite a different kind, such as fruits of all kinds, raw flesh, and live insects, which they seize and devour. They sometimes do dreadful damage in bee-hives, devouring the honey, and killing the bees. They do not gather wax; their nests and their combs are composed of a matter resembling grey paper, which they get from rotten wood, and which they scrape off with their jaws; they make a sort of paste of these scrapings by moistening them with a certainliquid which they disgorge. The cells in the combs are hexagonal, and very regular, like those of bees."[99]
Fig. 347.—The Hornet (Vespa crabro).
Wasps collect the materials with which they build near the place where they have chosen to establish their domicile. These materials are ligneous fibre, mixed up with saliva, with the aid of which these insects prepare the paper-like substance, which is very tough, and destined to form the walls of the cells and their exterior covering. The greater number make their habitation in the ground. Of these is our Common Wasp (Vespa vulgaris), which is black, agreeably contrasted with bright yellow. The Bush Wasp (Vespa norvegica), which inhabits woods, constructs its nest between the branches of shrubs or bushes. It is smaller than the common species. The Hornet is the largest European species of the family of theVespidæ. The substance of its nest is yellowish, and very fragile, and is constructed under a roof, in a loft, or in the hole of an old wall, but most often in the hollow of a decayed tree. Another species of this family (Polistes gallica,Fig. 348) fixes its little nest by a footstalk to the stem of some plant.
Fig. 348.—Polistes gallica.
Wasps begin laying in spring, and go on laying all the summer. Each cell receives one single egg, and, as with bees, the workers' eggs are the first laid. Eight days after the laying, there comes out of each egg a larva without feet, and already provided with two mandibles. These larvæ receive their food in the form of balls, whichthe females or the workers knead up with their mandibles and their legs before presenting to their nurslings, very nearly in the same way as birds give their beak full of food to their little ones. At the end of three weeks the larvæ cease to take food, and begin to shut themselves up in their cells, the interior of which they line with a coating of silk. In this they change their form, and assume the appearance of the perfect insect, with its six legs and its wings, but motionless, and contracted together. A sort of bag keeps all the organs swathed up together (Fig. 349). This pupa state lasts for eight or nine days, at the end of which time the insect is fully developed; it casts its skin, breaks the door of its prison, and launches itself into the air. A cell is no sooner abandoned than a worker visits, cleans it, and puts it in a fit state to receive another egg.
Fig. 349.Pupa of thecommon wasp.
During the summer the female wasp remains constantly in the nest, absorbed with family cares. She is occupied in laying eggs and in feeding her progeny, with the active assistance of the workers, or mules, as Réaumur and Charles de Geer call them, because they are unfruitful.
In the interior of the nests you generally find the most perfectly good understanding existing, and the most perfect order, in spite of the warlike instincts of these insects. It is only on rare occasions that this domestic peace is disturbed by the quarrels of male with male or worker with worker; but these combats are not deadly. Never, moreover, has one nest of wasps been known to declare war against another for the purpose of robbing it. "The government of wasps," says M. Victor Rendu, "explains very well the gentleness of their public conduct. Amongst them there are no despots; no one either reigns or governs; each one lives at liberty in a free city, on the sole condition of never being a burden to the state. They all act in concert, without privileges or monopolies, under the influence of a common law—the great law of the public good, from which no one is exempted."[100]
But this model republic is fatally doomed to early destruction. At the approach of winter all the workers, as also the males, perish. Some pregnant females alone hold out against the cold, and get through the winter, to propagate and perpetuate their species. Before dying, these insects destroy all the larvæ which are not hatched at the first approach of cold weather. In spring the femalesrevive, and begin alone the construction of a new nest. They then lay workers' eggs, which are not long in furnishing them a whole regiment of devoted and active assistants. These traits are pretty nearly the same for the different species of wasps, the only difference being in the way in which they build their nests.
Fig. 350.—Exterior of a Wasp's Nest on a branch of a tree.Fig. 350.—Exterior of a Wasp's Nest on a branch of a tree.
We have already said that the common wasp makes its nest in the ground. A gallery, of about an inch and a half in diameter, leads to the nest, situated at a depth which varies from six inches to two feet. "It is," says Réaumur, "a small subterranean town, which is not built in the style of ours, but which has a symmetry of its own. The streets and the dwelling-places are regularly distributed. It is evensurrounded with walls on all sides. I do not give this name to the side of the hollow in which it is situated; the walls I allude to are only walls of paper, but strong enough, nevertheless, for the uses for which they are intended." Generally, the shape of the outside of a wasp's nest is spherical or oval, sometimes conical. Its diameter is about from twelve to sixteen inches, its surface, which resembles a mass of bivalve shells, has one hole for entrance, and another for exit, just large enough to allow of one single wasp passing in or out at the same time (Fig. 350).
Fig. 351.—Interior of a Wasp's Nest, after Réaumur.Fig. 351.—Interior of a Wasp's Nest, after Réaumur.
The wasps' nest is composed, in the interior, of fifteen or sixteen horizontal galleries, arranged in storeys, and supported by numerous pillars of separation. We give here (Fig. 351) a section and view ofthe interior, drawn from memory by Réaumur.[101]The cakes forming the combs are composed of hexagonal cells, which are always used as cradles, never as storehouses. They open below. The exterior envelope of the nest is made with leaves of a sort of greyish, very gummy paper, which is applied layer by layer. Réaumur has given a very detailed account of the way in which these insects construct their nests.[102]They collect fibres of wood—which are their raw material—make them into a sort of coarse lint, which they reduce to balls, and carry between their legs to the nest. These balls are next stuck on to the work already begun. Then the insect stretches them out, flattens them, and draws them into thin layers, as a bricklayer spreads mortar with his trowel. The wasp works with extreme quickness, always backwards, so that it may have incessantly before its eyes the work it has done: the movement of its mandibles is even quicker than that of its legs.
Towards the end of summer the nest may contain 3,000 workers, and many females, who live together in perfect harmony. The number of males exceeds that of the females. A female weighs, by herself, as much as three males or six workers. With the exception of those which are occupied in building and in taking care of the eggs, all wasps go out hunting during the day. They are carnivorous, and may be seen attacking other insects, which they tear to pieces after having killed, so as to carry the bits to their nests, where thousands of mouths are clamouring for their food. The wasp pays great attention to the vines. It penetrates also into the interior of our houses, and infests the butchers' shops; but this the butchers do not much mind, for the wasp drives away the flies which would lay their eggs on the meat and thus contribute to its corruption.
As the winter approaches, the wasps go out less and less, and very soon cease to do so at all. The greater number then die, huddled up in their nest. A few females only, as we have said, get through the cold season. They sleep with their wings and legs folded up, which gives them the appearance of chrysalides. They can nevertheless sting in this state, as M. Guérin-Méneville found out to his cost. The spring wakes them up, and they then found new colonies. "It is at this season," says M. Maurice Girard, in his book on the "Metamorphoses of Insects," "that, with a little trouble, it would be easy to diminish in a very perceptible degree the number of wasps, which are, later, so destructive to the fruit, by catching innets the females, which might be attracted in quantities by means of the blossom of the black currant." This is a useful hint to gardeners.
The Hornets are distinguished from other wasps by their great size. They make their nests in the trunks of old trees, perforating the sound wood to arrive at the heart, which is rotten, or hollowing for themselves a hole, which they clear out by the gallery which leads to it. In this hole they construct first a dome suspended to the top by a footstalk; then a series of combs composed of cells, hanging the first to this dome, the second to the first, and so on, by stalks or pillars of a paper-like substance. When fixed under roofs, these insects have often the form of an elongated pear.Fig. 352represents one of these nests, after Réaumur. The societies of hornets contain fewer members than those of the common wasp; at most 200 insects.
Fig. 352.—Hanging Hornet's Nest.Fig. 352.—Hanging Hornet's Nest.
ThePolistesare a peculiar kind of wasp, smaller than the others, slender, with the abdomen tapering towards the base. The construction of their nests is more simple, having no envelopes, as shown inFig. 353. They attach them to the stems of broom, furze, or other shrubs, by a footstalk, or pedicle. They are like littlepaper bouquets, composed of from twenty to thirty cells, grouped in circle.
Fig. 353.—Nest ofPolistes gallica.
Fig. 354.—The Card-making WaspFig. 354.The Card-making Wasp(Chartergus nidulans).
The Card-making Wasp of Cayenne (Chartergus nidulans,Fig. 354) is a consummate artist. Its nest represents a sort of box or bag, made of a substance resembling cardboard, so fine and so white that the best worker in that material would be deceived by it. This nest has only one single hole at its base; each of the combs it contains is likewise pierced by a hole in its centre, to afford a passage to the wasps. In an architectural point of view, the card-making wasp is almost superior to the bee, for the latter does notbuildits house, it onlyfurnishesit, as Latreille remarks with truth. The Brazilian species ofChartergus, which the inhabitants call Lecheguana,[103]manufactures a honey, the use of which is not without danger, as it occasions vertigo and sharp pains in the stomach. The naturalist, Auguste Saint-Hilaire, during his sojourn in Brazil, himself experienced ill effects from eating it.
There are, moreover, solitary wasps, which make their cells in holes which they scoop out in the ground, or in the stalks of certain plants. In the adult state these live on honey; but their larvæ are carnivorous, and the female is obliged to bring them living insects. The commonest of these solitary wasps belong to the genusOdynerus.This insect makes its nest in the stalk of a bramble or briar (Fig. 358) with a mortar which it prepares. The larva (Fig. 356) lines its cell with a silky cocoon. It is the last egg laid which is hatched the first; then come the others, in an inverse order from that in which they were deposited. If it had been in the other order, the insects could not have come out of the cells without destroying on their way the less advanced pupa.
Fig. 358.—Nest of an Odynerus in the stem of a bramble.
Ants.
The habits of the Ants are as remarkable as the habits of the bees. In their marvellous republics each one has his fixed duties to perform, of which he acquits himself willingly and without constraint. In consequence of their habits of foresight and frugality, ease reigns in the dwellings of these little animals, which become attached to their nest by a feeling of patriotism. Woe betide him who disturbs them in their occupations, or destroys their house! Like bees, they form a regular republic, composed—first, of males; secondly, of females; thirdly of neuters, or workers. We shall see, further on, the labours and the part played by each one of these three orders of the republic. Let us speak first of the species.
Ants are divided into a great number of species, which have been carefully described by De Geer, Latreille, and Francis Huber, the son of the celebrated blind man who wrote the history of bees. All these species have, however, some general traits in common, by which they may be easily distinguished from all other insects. Ants have a slim body on long legs. The workers are stouter and smaller than the males; and these last are smaller than the females. The males have large and prominent eyes, whilst the eyes of the workers and females are small.
Ants are provided with antennæ, bent in the form of an elbow, with which they examine everything they meet, and which seem to assist them in the communication of their ideas. Two horny, very strong mandibles serve them at the same time as pincers, tweezers, scissors, pick-axe, fork, and sword. A thin short neck joins the head to the thorax, to which, in the case of the males and females, are attached four large veiny wings. The workers only have no wings. Of the three pairs of legs, the hind ones are the longest. Each pair is armed with a spur, and fringed with very short hairs, which serve the purpose of brushes. The abdomen, large, short, oval, or square, is always most voluminous in the females.
There are three genera of ants which we shall mention. TheMyrmicæhave two knobs to the pedicle, by which the abdomen is attached to the thorax; thePoneræonly one. In these two genera, the females and the neuters have a sting, and the larvæ do not spin a cocoon in which to change into pupa. Lastly, theFormicæ—ants properly so called—have but one knob on the pedicle of theabdomen, as inPonera; their larvæ spin a silky cocoon. They have no sting, but they pour into the wounds made by their mandibles an acid liquor, the pungent smell of which is well known. This liquid is formic acid, a natural product, which the chemist now-a-days knows how to make artificially, by the action of dilute sulphuric acid on maize and other vegetable matters. Their whole body is impregnated with this acid, and has a strong sour smell. Some people like to chew ants, on account of their sourish taste. "They also make," says Charles de Geer, "creams for side-dishes, to which these ants give, they say, the taste of lemon-juice." We know, in the south of France, people who have eaten thesecrèmes aux fourmis!Polyergusforms a sub-genus ofFormica.
Fig. 361.—Sections of an Ant's Nest.Fig. 361.—Sections of an Ant's Nest.
In all these species, the workers, or neuters, have the charge ofthe building, provisioning, and rearing of the larvæ—in fact, all the care of the household, and the defence of the nest. Deprived of wings, they are bound to the soil, and condemned to work. As compensation, to them belong strength, authority, power: nothing is done but through them. "Born protectors of an immense family still in the cradle," says M. Victor Rendu, "by their vigilance, their tenderness, and their solicitude, without being mothers themselves, they share in the duties and joy of maternity. Alone, they decide on peace or war; alone, they take part in combats: head, heart, and arm of the republic, they ensure its prosperity, watch over its defence, found colonies, and in their works show themselves great and persevering artists."
The nests of ants (Figs.361,362) are known under the name of ant-hills. They vary very much, both as to their form and the materials employed in making them—wood and earth are the principal. That which strikes one at first sight, is the size of these dwellings, which form a curious contrast to the smallness of their builders. Each species of ant has an order of architecture peculiar to it. The Red Ant (Formica rufa), one of the commonest in our woods, constructs a little rounded hillock with all kinds of objects—fragments of wood, bits of straw, dry leaves, the remains of insects, &c. This hillock, the base of which is protected by material of greater solidity, is nothing more than the exterior envelope of the nest, which is carried underground to a very great depth. Avenues, cleverly contrived, lead from the summit to the interior. The openings vary in width; and, as night approaches, are carefully barricaded. They are opened every morning, except on rainy days, when the doors remain shut, and the inhabitants confined within.
The ant-hill, orformicarium, is at first simply a hole hollowed out in the soil, the entrance to which is masked by the building materials. But the miners do not cease to hollow out galleries and chambers, arranged by stories. The earth and rubbish are carried out, and serve to construct the upper edifice, which rises at the same time that the excavation grows deeper. It is a labyrinth bored in all directions. It contains corridors, landings, chambers, and spacious rooms, which communicate with each other by passages which are often vertical. All the corridors lead to a large central space, loftier than the others, and supported by pillars; it is here that the greater number of the ants congregate. These ant-hills often rise to a height of fifteen inches above the ground, and descend to an equal depth.Fig. 362shows the interior of an ant-hill, drawn from Nature. Outside it are to be seen some ants occupied in sucking plant-lice.
Fig. 362.—Section of an Ant-hill.Fig. 362.—Section of an Ant-hill.
The group of Mason Ants contains a great number of varieties: the Ashy-black Ant (Formica nigra,Fig. 363), the Brown, the Yellow (Formica flava), the Blood-red, the Russety (Polyergus rufescens), the Black, the Miner (Formica cunicularia), the Turf Ant, &c. All these species employ a mortar, more or less fine, in raising their hillocks, at the same time that they hollow out their underground dwellings. The Jet Ant (Formica fuliginosa) excavates wood, hollowing out its labyrinth in the trunk of a tree with consummate skill. The Red Ant (Myrmica rubra) plies, according to circumstances, the trade of a mason or excavator.
Fig. 363.—Ashy-black AntFig. 363.—Ashy-black Ant (Formica nigra). Male, female, and worker.
The masons work when they can profit by the rain or by the evening dew, to make their mortar. They only go out after sunset, or when a fine rain has wetted their roof. Then they set to work. They roll up pellets of earth, bring them back in their mandibles, and stick them on to those places where the building was left unfinished. From all sides the earth-workers may be seen arriving, laden with materials. All these are bustling, hurrying, busy, but always in the greatest order, and with a perfect understanding among themselves. Every part of the building is going on at the same time. The apartments spring up one above another, and the edifice visibly rises. The rain, the sun, and the wind consolidate and harden the building socunningly contrived by these industrious workers, who have received from God alone their marvellous science. With no other tool than their mandibles, the excavators work their way through the hardest wood. They bore holes right through it, riddling it completely with numerous storeys of horizontal galleries. The Yellow Ant raises its little hillocks in fields, and passes the winter in a burrow or underground dwelling-place.
Fig. 364.—Ashy Ant. Male, worker, and female.Fig. 364.—Ashy Ant. Male, worker, and female.
Independent of the principal entrances, there exist, in some nests, masked doors guarded by sentinels. Many species also hollow out covered galleries, which they only unmask in extreme danger, either to open an outlet for the besieged, or to turn the enemy who has already invaded the place. Ant-hills are, in fact, perfect fortresses, defended by a thousand ingenious contrivances, and guarded by sentinels always on thequi vive.
The domestic life of the different species is nearly the same. The birth and rearing of the little ones, and the duties of the adults, do not differ perceptibly from each other in the various species of ants. The females live together in harmony. They lay, without ceasing to walk about, white eggs of cylindrical form and microscopic dimensions. The workers pick them up, and carry them to special chambers. In a fortnight after the laying, the larva (Fig. 365) appears. Its body is transparent. A head and wings can be made out, but no legs; the mouth is a retractile nipple, bordered by rudimentary mandibles, into which the workers disgorge the juices they have elaborated in their stomachs; and as they lay by no provisions,they are obliged to gather each day the sugary liquids destined for the food of the larvæ.
From their birth, a troop of nurses is charged with the care of them. They put them out in the open air during the day. Hardly has the sun risen, when the ants, placed just under the roof, go to tell those which are beneath, by touching them with their antennæ, or shaking them with their mandibles. In a few seconds, all the outlets are crowded with workers carrying out the larvæ in order to place them on the top of the ant-hill, that they may be exposed to the beneficent heat of sun. When the larvæ have remained some time in the same place, their guardians move them away from the direct action of the solar rays, and put them in chambers a little way from the top of the hill, where a milder heat can still reach them. We then see the ants themselves taking the well-earned luxury of a few minutes' rest, heaping themselves up together, right in the sun. There is no observant inhabitant of the country who has not seen the curious spectacle which we have just mentioned—that is to say, the population of an ants' nest carrying into the sun the young nurslings, so that they may experience the action of the solar heat. We recommend the dweller in towns who is in the country for a day to stretch himself out near an ant-hill in the warm weather, and witness this spectacle, one of the most curious in Nature. The care which the working ants bestow on their young does not consist only in nourishing them and procuring for them a proper temperature; they have also to keep them extremely clean. With their palpi they clean them, brush them, distend their skin, and thus prepare them for the critical trial of their metamorphosis.
At this moment the larvæ of ants, properly so called, spin themselves a silky cocoon, of a close tissue and of a grey or yellowish colour; those of theMyrmicæand of thePonerædo not surround themselves with a silky cocoon before changing into pupæ. These are at first of a pure white, but they very soon assume a brown colour, which increases until it becomes dark brown. They possess all the organs of the adult, enveloped in a membrane so thin that it seems to be iridescent.Fig. 366represents the pupa of the red ant. They are the cocoons enclosing the pupæ, which are incorrectly called in the country ants' eggs, and are given to young pheasants and partridges. The pupæ remain motionless till the insects emerge, which is accomplished with the assistance of the workers. These latter tear the covering from the pupa, and complete its deliverance. They then watch over the newly-born ant. For some days they feed it, help it to walk, and do not abandon it till it can dispense with their good offices. These workers, when provisions fail, or when the ant-hill is threatened with any great danger, take in their mandibles the eggs, the larvæ, the pupæ, and sometimes those females and the males which refuse to follow them. Thus laden, they go their way, to seek for another country they may call their own. They never forget, in their hurried emigrations, the infirm or sick workers, which would perish in the house now abandoned and deserted.
The males and females lately hatched do not enjoy the same liberty as the young workers. They are confined to the ant-hill, where they are kept in sight till the day of the general departure. It is towards the end of the month of August that swarms of winged ants of both sexes are seen to issue forth. The males come out first, agitating their iridescent and transparent wings. The females, less numerous, follow them closely. All of a sudden one sees this troop raise itself at a given signal, and disappear in the air, where the coupling takes place. The males perish immediately afterwards. The females impregnated return to the paternal home, or else found new colonies with the assistance of a few workers who are their escort. From this moment they no longer require wings. The workers make haste to cut them off, or, indeed, which oftenest happens, they themselves tear them off. With their wings they lose the desire for liberty. Henceforward, they will quit their retreat no more, the cares of their approaching maternity now alone occupying them. The working ants reserve for them subterranean chambers, where they are kept in sight by the sentinels. At certain hours only are they to be met with in the upper storeys. When they wish to walk, a company of guards presses round them on all sides so as to prevent them from advancing too quickly. There are no sorts of attentions they do not heap upon them to make them forget their captivity. They caress them, brush them, lick them, they offer them food continually. On the least appearance of danger, the workers take possession, first of all, of the pregnant females, and drag them out by the secret outlets, so as to put in a place of safety their precious persons, the hope of the community. The workers' task is immense, for their labours increase in the same proportion as the population increases. But the division of work and the good understanding which exists between the members of the community, allow them to be prepared for anything that may happen, and to supply all their necessities.
Nothing is more amusing than to observe the shifts ants are put to in transporting objects of great size. They stumble, they tumble head over heels, they roll down precipices; but, in spite of all accidents, return to their task, and always accomplish it.The tranquil inhabitants of these subterranean republics are bound together by mutual affection in a devoted fraternity, which makes them ever ready to assist each other. They all help one another as much as they can. If an ant is tired, a comrade carries it on its back. Those which are so absorbed with their work that they have no time to think of their food, are fed by their companions. When an ant is wounded, the first one who meets it renders it assistance, and carries it home. Latreille having torn the antennæ from an ant, saw another approach the poor wounded one, and pour, with its tongue, a few drops of a yellow liquid on the bleeding wound.
Huber the younger one day took an ant's nest to populate one of those glass contrivances which he used for making his observations, and which consisted of a sort of glass bell placed over the nest. Our naturalist set at liberty one part of the ants, which fixed themselves at the foot of a neighbouring chestnut tree. The rest were kept during four months in the apparatus, and at the end of this time Huber moved the whole into the garden, and a few ants managed to escape. Having met their old companions, who still lived at the foot of the chestnut tree, theyrecognisedthem. They were seen, in fact, all of them, to gesticulate, to caress each other mutually with their antennæ, to take each other by the mandibles, as if to embrace in token of joy, and they then re-entered together the nest at the foot of the chestnut tree. Very soon they came in a crowd to look for the other ants under the bell, and in a few hours our observer's apparatus was completely evacuated by its prisoners. When an ant has discovered any rich prey, far from enjoying it alone, like a gourmand, it invites all its companions to the feast. Community of goods and interests exists amongst all the members of this model society. It is the practical realisation of the dream formed by certain philosophers of our day, who were only able to conceive the idea, the possibility, the project of such a community of goods and interests, which is among ants a reality.
How do these insects manage to make themselves understood in such various ways, asking for help, giving advice, giving invitations? They must have a language of their own, or else they must communicate their impressions by the play of their antennæ.
When an ant is hungry, and does not wish to disturb itself from its work, it tells a foraging ant as it passes, by touching it with its antennæ; the latter approaches it immediately, and presents it, on the end of its tongue, some juice it has disgorged for this purpose. The antennæ, then, are used by the ants for the purpose of making themselves understood by each other. Dr. Ebrard, who studied theseinsects attentively, is of opinion that they use them in the same way as a blind man does his stick, to feel their way with, for their sight is not good. The age to which ants live is not well known. It is believed that the workers live many years.
Ants eat all sorts of things. One sees them eating fresh or decaying meat, fruits, flowers, particularly everything which is sugary. They attack living insects, and kill them and suck their blood. Like many insects, they are very fond of sugary liquids—honey, syrups, pure sugar, &c. Dupont de Nemours relates in his Memoirs that, to guarantee his sugar-basin against the invasion of ants, he had found no better plan than to make it "an island," that is to say, to place it in the middle of a vessel full of water. He felt sure that he had made the fortress safe against any attack; but listen to the stratagem made use of by the besiegers. The ants climbed up the wall to the ceiling, exactly perpendicularly over the sugar-basin. From there they let themselves fall into the interior of the place, penetrating thus by main force, and without injuring any one, into the magazine. As the ceiling was very high, the draught caused them to deviate from the straight line, and thus a certain number fell into the fosse of the citadel, that is to say, into the water in the vessel. Their companions stationed on the bank made all efforts imaginable to fish out the drowning ants, but were afraid of taking to the water of such a large lake. All that they could do was to stretch out their bodies as far as possible (keeping on the bank the while), to lend a helping hand to their drowning friends. Nevertheless, the salvage did not progress much; when the ants, which were getting very uneasy, conceived a happy thought. A few were seen to run to the ant-hill, and then to reappear. They brought with them a squad of eight grenadiers, who threw themselves into the water without any hesitation, and who, swimming vigorously, seized with their pincers all the drowning ants, and brought them all on toterra firma. Eleven, half-dead, were thus brought to shore, that is, to the rim of the basin. They would probably all of them have succumbed, if their companions had not hastened to lend them assistance. They rolled them in the dust, they brushed them, they rubbed them, they stretched themselves on their dying companions to warm them; then they rolled them and rubbed them again. Four were restored to life. A fifth half recovered, and, still moving its legs and its antennæ a little, was taken home with all sorts of precautions. The six others were dead. They were carried into the ant-hill by their afflicted companions. It seems like a dream to read such things as this, and yet Dupont de Nemours tells us, "I have seen it!"Ants are also very fond of a peculiar liquid which the plant-lice secrete from a pouch in the abdomen. When they have got possession of a plant-louse, they excite it to secrete this liquid, but without doing it any harm. They carry the plant-lice into the ant-hill, or into private stables. There they keep them, give them their food, and suck them. We have already mentioned these curious relations which are established between ants and plant-lice.[104]Fig. 367 shows an ant thus occupied. TheGallinsectaalso furnish the ants with sugary liquids.
During the cold of winter the ants sleep at the bottom of their nests, without taking any food. A small number of species only hold out through the severe season, by shutting themselves up in the ant-hill with a number of plant-lice. It is thus that they pass the winter with a supply of food. We must mention, however, that in warm countries the ants do not hybernate.
We have just described ant society during the quiet periods, when peace reigns supreme; but they are not more exempt than other animals from the necessities and dangers of war. They have a great many enemies among the population of the woods; they must, then, be prepared to repel their attacks. They display in that the most scientific resources of the military art applied to defence.
It is almost needless to say that the sentinels are, at all times, posted at a reasonable distance from the ant-hill, to observe the environs. When the fortress is unexpectedly attacked, whether by large insects, Coleoptera for instance, or by the ants from a neighbouring nest, these vigilant sentinels immediately fall back and give the alarm to the camp, not, however, without having boldly confronted the enemy and opposed to him an honourable resistance. Having re-entered the nest in all haste, they precipitate themselves into the passages, tapping with their antennæ all the ants which they meet, and thus spreading the alarm in the city. Very soon the agitation has become general, and thousands of combatants sally forth from the citadel, ready to repel the attack and make the enemy bite the dust.