IX.COLEOPTERA.In collections of insects the Coleoptera almost always occupy the principal place. They are sought after by collectors on account of the brightness of their colours, of the solidity of their integuments, and the facility with which they can be preserved. This circumstance has contributed much to give to the Coleopterous Order marked preponderance in the immense series of insects. Many more have been collected than any one has as yet been enabled to describe; and the collections are encumbered with species of which no naturalist has yet given an account.Admitting that the first-rate collections contain each about 25,000 perfectly distinct species, and that a certain fraction of these treasures is peculiar to each collection, M. Blanchard came to the conclusion that we must estimate the number at more than 100,000 of the species of Coleoptera which would be obtained if the different entomological collections of France, England, and Germany were put together. But every day we see arriving from different regions of the globe new riches, hardly dreamt of up to that time; and it is not only the small species, but the larger and more beautiful also, which furnish their contingent. It may, then, be believed that, if the entire surface of the earth were carefully explored, we should obtain an incalculable number of Coleoptera, having sufficient characteristics to constitute distinct species or kinds.The Coleoptera (from [Greek: koleos], a sheath, and [Greek: pteron], a wing) are insects with four wings. The anterior wings, orelytra, are not used in flying; they are sheaths, more or less hard, sometimes varied with bright colours, and never crossing over each other. The posterior wings are membranous, presenting a ramification of veins, and usually folding up under theelytra, which protect them when at rest. The mouth of Coleoptera is provided with mandibles, with jaws, and two quite distinct lips, and is suited for mastication. They undergo complete metamorphosis. After an existence of greater or less extentin the larva state (in the case of the cockchafer three years), the insect changes into a pupa, which remains in a state of complete immobility. After a certain time, the pupa bursts its envelope and assumes the form of a perfect insect. The Coleoptera presents the utmost variety of habits as regards their habitations and food. One does not find in this Order those admirable instincts, those manifestations of intelligence, which bring certain Hymenoptera near to those beings which are highest in the animal scale; but they offer peculiarities very well deserving serious and profound study. Some are carnivorous, and thus they are useful to man in destroying other noxious insects, which they seek on the ground, on low plants, on trees, and even in the depths of the waters. Many of these Coleoptera feed on animal matter in a state of putrefaction. We may look on them as useful auxiliaries: they are Nature's undertakers.A great number live in the excrements of animals. The dung of oxen, buffaloes, and camels afford shelter to Coleoptera of different families, which thus live on vegetable matter more or less animalised. Others attack skins and dried animals in general; and some are the pest of entomological collections. Lastly, immense legions of Coleoptera are phytophagous; that is to say, they attack roots, bark, wood, leaves, and fruits, and cause much annoyance to the agriculturist. Above all, the larvæ are to be dreaded. Those which live in wood may in a few years occasion the loss of trees, vigorous and full of life; or completely destroy the beams of a building. Certain larvæ, such as those of the cockchafer, eat away the roots of vegetables, and so destroy the harvests. Others, lastly, devour the leaves and the stalks of plants, attack the flowers in the gardens, or the corn in the barns; and so man makes desperate war against them.In the immense variety of known Coleoptera we must be contented to choose those types which are most prominent and most characteristic. We will begin with theScarabæides, with their heavy compact body, and short antennæ, terminated by a foliaceous club. It is to this tribe that belongs the beautiful Rose Beetle (Cetonia aurata), which lives on roses; the Cockchafer (Melolontha vulgaris); theScarabæusof the Egyptians; &c.This is the most interesting tribe of the whole Order Coleoptera. It corresponds with the great division of theLamellicornesof Latreille. This name ofLamellicorneswas intended to remind us of the arrangement into laminæ, more or less close together, of the club of the antennæ of these insects. ManyScarabæihave their mandibles membranous, or at least partially so, and always small. This peculiarity corresponds to their habits. Never, indeed, have they totriturate hard bodies; they all feed either on flowers, on leaves, or on stercoraceous matter. Their larvæ resemble each other much, even those of families very widely differing from each other in the perfect state. They are large, whitish worms, with diaphanous skins, scaly heads, furnished with toothed mandibles, living in the ground or in rotten wood. The pupæ are fat and stumpy, and they already show the features of the perfect insect. They make a chamber in which to undergo their changes. They remain generally three years in the larva state. The duration of the pupa is very short, as also is that of the perfect insect. The differences of the sexes are often very marked on the exterior, by protuberances, horns, &c., which constitute the distinctive ornament of the males.In the group ofScarabæideswe shall have to speak, above all, of theCetoniadæ, the Chafers, and theScarabæiproperly so called. The familyCetoniadæis one of the most remarkable, on account of the beauty of the insects which compose it and of the richness of their metallic lustre, some being of great splendour, and others having velvety tints. The larvæ live in wood in a state of decomposition; the perfect insects frequent flowers, and like the sun.Fig. 423.—Rose Beetle (Cetonia aurata).This family contains a great number of species, the type of which is the Rose Beetle (Cetonia aurata), of a beautiful green colour shot with gold, with transverse whitish lines. The rose beetle frequents roses especially, of which it eats the petals and the stamens. It is theGolden Melolonthaof Aristotle, who tells us that this unfortunate insect shared with the cockchafer the privilege of amusing children. TheCetoniaflies by day and by night, making use of its inferior wingswithout opening the elytra (Fig. 423). When seized, it pours out from the extremity of its abdomen a fœtid liquid, the only means of defence the poor insect possesses. The larva (Fig. 424) much resembles the larva of the cockchafers, but the legs are shorter. It is found in rotten wood, and often in ants' nests. When it has acquired its full development it makes a cocoon of an oval form (Fig. 424), in which it transforms itself into a pupa; the cocoon is composed of bits of wood agglomerated with a silky matter which the larva secretes.Fig. 424.—Larva and cocoon of the Rose Beetle.The larva of theCetonia splendidula—which is the most magnificent found in France—is met with sometimes in the nests of wild bees. In Russia the rose beetle is considered a very efficacious remedy for hydrophobia. In the governorship of Saratow, which is traversed by the Volga, hydrophobia is very frequent, on account of the heats which reign during the whole summer in its arid steppes. The inhabitants, incessantly exposed to be bitten by mad dogs, have tried in succession a great many preparations to remedy the results of these terrible accidents. It appears that theCetonia, dried and reduced to powder, has produced on many occasions good effects. This is the recipe which an inhabitant of Saratow published in a Russian journal—adding, that he had employed it for thirty years, that not one of the patients treated by him had died, and that his remedy could be employed with success in all the phases of the disease:—In spring they search at the bottom of the nests of the wood ant for certain white larvæ, which they carefully preserve in a pot, together with the earth in which they were found, till the moment of their metamorphosis, which takes place in the month of May. The insect, which is the common rose beetle, is killed, dried,and kept in pots hermetically sealed, so that it may preserve the strong odour which it exhales in spring, which seems to be a necessary condition of the remedy proving efficient. When a case of hydrophobia presents itself, they reduce to powder some of these, and spread this powder on a piece of bread-and-butter, and make the patient eat it. Every part of the insect must enter into the composition of this powder, which, for this reason, cannot be very fine. During the whole time a patient is under treatment he must avoid drinking as much as possible, or, if his thirst is very great, he must only drink a little pure water; but he may eat. Generally, this remedy produces sleep, which may last for thirty-six hours, and which must not be disturbed. When the patient wakes, he is, they say, cured. The bite must be treated locally with the usual surgical appliances.As to the dose of the remedy, that depends on the age of the patient and the development of the disease. They give, to an adult, immediately after the bite, from two to three beetles; to a child, from one to two; to a person in whom the disease has already declared itself, from four to five. Given to a person in good health, the remedy, however, would not be the least dangerous. In cases in which the symptoms of hydrophobia show themselves some days after the employment of the remedy, they recommence the treatment. They have also tried to prepare this remedy with insects collected not in their larvæ but in the imago state, by catching them on flowers, and it seems that these attempts have succeeded. According to M. Bogdanoff, in many governorships of the south of Russia the lovers of sporting are in the habit of making their dogs from time to time swallow (as a preservative) half of aCetoniawith bread or a little wine. Every one in those countries is persuaded of the efficacy of this means for stopping the development of the disease. One ought not, perhaps, to reject a belief so widespread and deeply rooted without some experiments to guarantee us in doing so, for medicine does not yet possess any remedy against hydrophobia: it might not then be useless to try this.Two smaller species than the rose beetle, theCetonia sticticaand theCetonia hirtella, which has yellowish hairs, live on the flowers of thistles. Western Africa, the Cape, Madagascar, &c., are very rich in species ofCetoniæ. Among theCetoniadæis the genusGoliathus, gigantic insects which inhabit Africa. Their total length sometimes attains from three to five inches. Their colours are generally a dull white or yellow, which has nothing metallic about it, with spots of a velvety black—these are due to a sort of down of an extreme thinness, and which very easily comes off. The head of these enormous Coleoptera is generally cut or scooped out, and is adorned sometimes with one or two horns. Their legs, strong and robust, are armed with spurs, and sometimes present on their exterior sharp indentations, which give to these insects a crabbed physiognomy, which their inoffensive habits are far from justifying. All these horns, and all these teeth, which look so terrible, are nothing, in fact, with a great number of these insects, but simple ornaments. They compose the picturesque uniform of the males. They are equivalent to the bear-skin caps, the flaming helmets, and the bullion-fringed epaulettes of our soldiers. The dress of the femaleGoliathusis much more modest, as is becoming to the sex. We here represent theGoliathus Derbyana(Fig. 426) and Polyphemus (Fig. 427).Fig. 425.—Cetonia argentea.Fig. 425.Cetonia argentea.The Goliaths were formerly excessively rare in collections, and of a price inaccessible to ordinary amateurs—one single specimen costing as much as twenty pounds. But for some time the Goliaths of the coast of Guinea and of Cape Palmas have been sold to European amateurs at a modest price, thanks to those travellers who, after the example of Dr. Savage, have collected them by hundreds in the countries which produce them. These enormous Coleoptera are seen on the coast of Guinea fluttering about at the top of trees, the flowers of which they are seeking after. To catch them the trees are felled or else they are shot at with a gun loaded with sand, as is also done for the humming-birds. The species which Dr. Savage made common is theGoliathus cacicus, of which we represent the male and female (Figs. 428, 429). It is met with on the coast of Guinea. TheGoliathus Druryi(Fig. 430) inhabits Sierra Leone, on the west coast of Guinea. The numerous expeditions which are at the present moment being made into the interior of Africa will not fail to increase the number of species of these splendid insects, which are the ornament of all collections.The group of theTrichiadæ, which has in this country and in France a few representatives, is very nearly the same as that of theCetoniadæ. TheTrichiadæhave the elytra shorter, the abdomen bigger, and the legs more slender. TheTrichius fasciatus, which is black, and covered with an ashy down, with the elytra yellow, and with three black bands, is to be met with in quantities on the garden rose-tree, in the months of June and July. The larvæ live in the interior of old beams of wood, respecting their surfaces. In a garden, at a few leagues from Paris, a little wooden bridge had been built. It seemed on the outside to be in a perfect state of preservation. Nothing on the exterior would have led one to think it was possible for the oak timbers which composed it to break down. A good many of them, however, broke suddenly. It was then seen that the wood had been scooped out right up to the surface, which was nothing better than a thin sheet, of an imperceptible thinness. All the interior was full ofTrichii, in the states of larva, pupa, and perfect insect.Fig. 426.—Goliathus Derbyana.Fig. 427.—Goliathus Polyphemus.TheTrichius fasciatus, sometimes called the Bee Beetle, is verycommon in the environs of Paris. Geoffroy has described it under the rather quaint name of the "Livrée d'Ancre," because the Marquis of Ancre made his servants wear yellow coats, bordered by braid alternately crossed with green and yellow.Fig. 428.—Goliathus cacicus, male.Fig. 428.—Goliathus cacicus, male.Fig. 429.—Goliathus cacicus, female.Fig. 429.—Goliathus cacicus, female.TheOsmoderma eremitais a large insect, of purple colour,formerly common in the environs of Paris, and which, now-a-days, cannot be found nearer than Fontainebleau. One must look for them in earth which fills up the cavity of old willows or of pear trees. The smell of Russia leather, or of plum, which it exhales, has caused it to be called, in some places, the Plum-tree Beetle.Fig. 430.—Goliathus Druryi (natural size).Fig. 430.—Goliathus Druryi (natural size).TheGnorimus nobilismuch resembles the rose beetle, and is found on elder flowers, the whiteness of which this golden insect relieves. One species, much smaller, only one or two lines long, is theValgus hemipterus, which is often met with in spring, in the dust of the roads. The female has a long auger, which enables it to deposit its eggs in rotten wood. Dumeril has described at length the singular movements of this little insect:—The jerking and, as it were convulsive, movements by which it transports itself from one place to another; its tottering attitude, resulting from the excessive length of its hind legs; the vertical carriage of these, which, by their singular direction, interfere much with the walking, which is directed by the other legs. One should, above all, notice the artifice which theValgusemploys, as indeed do many Coleoptera, to escape from his persecutors, by counterfeiting death. As soon as it is seized by any enemy, its members stiffen and become motionless. The body, abandoned to itself, lies unevenly on whatever side it falls, for its legs no longer bend; if you bend them over, they remain in the inclination given to them. Nothing then betrays life in this little dry and slender being, frozen with fear, and imitating death, without, perhaps, being aware itself of what it is doing.We must still further mention here theIncas—beautiful insects of the same group, which are met with in South America, and whose males have an extraordinary head. They fly during the day round the great trees on which they live.Fig. 431represents theInca clathrata.The most commonly-known insect of the family with which we are now occupied is the cockchafer. The French word for cockchafer,hanneton, according to M. Mulsant, comes from the Latin,alitonus(which has sonorous wings), which first becamehalleton. Linnæus gave them first the name ofMelolontha, which they probably had among the Greeks, and which seems to be the case from this passage in Aristophanes, in his comedy of "The Clouds:"—"Let your spirit soar," says the Greek author, "let it fly whither it lists, like the Melolontha tied with a thread by the leg." We see that the habit of martyrising cockchafers is of very early date. The Common Cockchafer (Fig. 432) is one of the greatest pests to agriculture. In its perfect state it devours the leaves of many trees, principally thoseof the elm; and so children call the fruit of the elm-tree by the name of "Pains d'Hanneton." But the destruction which they occasion in their perfect state is little when compared with that which is caused by their larvæ—those white grubs so dreaded by agriculturists.Fig. 431.—Inca clathrata.Cockchafers make their appearance from the month of April, if the season is warm. But it is in the month of May that they show themselves in great quantities; and so they are called in GermanyMaikäfer(Maychafer). They are met with also in June. The duration of their life as a perfect insect is six weeks. They fear the heat of the day and the bright sunshine, so, during the day, they remain hooked on to the under surface of leaves. It is only early in the morning, and at sunset, that one sees the cockchafers fluttering round the trees which they frequent. They fly with rapidity, producing a monotonous sound by the friction of their wings. But the cockchafer steers badly when it flies; it knocks itself at each instant against obstacles it meets with. It then falls heavily to the ground, and becomes the plaything of children, who are constantly on the look-out for them. There is a saying, "Étourdi comme un hanneton." What contributes still more to render the flight of these insects heavy and sustained only for a short time together is that they are obligedto inflate themselves like balloons in order to rise into the air: it is a peculiarity which they share with the migratory locust. Before taking its flight, the cockchafer agitates its wings for some minutes, and inflates its abdomen with air. The French children, who perceive this manœuvre, say that the cockchafer "compte ses écus" (is counting its money), and they sing to it this refrain, which has been handed down for many generations:—"Hanneton, vole, vole,Va-t'en à l'école."A variation which we hear in the western provinces of France is the following:—"Barbot, vole, vole, vole,Ton père est à l'école,Qui m'a dit, si tu ne voles,Il te coupera la gorgeAvec un grand couteau de Saint-George."Fig. 432.—CockchaferFig. 432.—Cockchafer (Melolontha vulgaris).During the day the cockchafers remain under the leaves in a state of perfect immobility; for the heat which gives activity to other insects, seems, on the contrary, to stupefy them, and it is during the night only that they devour the leaves of elms, poplars, oaks, beech, birch-trees, &c. In years when their number is not very great, one hardly perceives the damage done by them; but at certain periods they appear in innumerable legions, and then whole parts of gardens or woods are stripped of their verdure, and present, in the middle of the summer, the appearance of a winter landscape. The trees thus stripped do not in general die; but they recover their former vigour with difficulty, and, in the case of orchard trees, remain one or two years without bearing fruit. It is principally the trees skirting woods, and situated along cultivated fields, which are exposed to the ravages of the cockchafer, because the larvæ of these insects are developed in the fields. In the interior of forests they are never met with in great numbers.In certain years cockchafers multiply in such a frightful manner that they devastate the whole vegetation of a country. In the environs of Blois 14,000 cockchafers were picked up by children in a few days. At Fontainebleau they could have gathered as many in a certain year in as many hours. Sometimes they congregate in swarms, like locusts, and migrate from one locality to another, when they lay waste everything. To present an idea of the prodigious extent to which cockchafers increase under certain circumstances,we will give a few statistics:—In 1574, these insects were so abundant in England that they stopped many mills on the Severn. In 1688, in the county of Galway, in Ireland, they formed such a black cloud that the sky was darkened for the distance of a league, and the country people had great difficulty in making their hay in the places where they alighted. They destroyed the whole of the vegetation in such a way that the landscape assumed the desolate appearance of winter. Their voracious jaws made a noise which may be compared to that produced by the sawing of a large piece of wood, and in the evening the buzzing of their wings resembled the distant rolling of drums. The unfortunate Irish were reduced to the necessity of cooking their invaders, and, for the want of any other food, of eating them. In 1804, immense swarms of cockchafers, precipitated by a violent wind into the Lake of Zurich, formed on the shore a thick bank of bodies heaped up one on the other, the putrid exhalations from which poisoned the atmosphere. On May 18, 1832, at nine o'clock in the evening, a legion of cockchafers assailed a diligence on the road from Gournay to Gisors, just as it was leaving the village of Talmontiers; the horses, blinded and terrified, refused to advance, and the driver was obliged to return as far as the village, to wait till this new sort of hail-storm was over. M. Mulsant, in his "Monographie des Lamellicornes de la France," relates that in May, 1841, clouds of cockchafers traversed the Saône, from the south-east in the direction of the north-west, and settled in the vineyards of the Mâconnais. The streets of the town of Mâcon were so full of them, that they were shovelled up with spades. At certain hours, one could not pass over the bridge without whirling a stick rapidly round and round, to protect oneself against their touch.XI.—A Diligence surrounded by a Cloud of Cockchafers.The coupling takes place towards the end of May, after which the males die; the females only surviving them from the time necessary to ensure the propagation of the species. The number of eggs which a female lays is from twenty to thirty. With her front leg she hollows out a hole in the ground from two to four inches in depth, and deposits her eggs, of a yellowish white and of the size of hemp-seed, therein. Her instinct leads her to choose soft, light, and well-manured soils, which are, at the same time, the best ventilated and the most fertile. We may conclude from this that cultivation and labour have made the cockchafer more common than it was formerly. It is the child of civilisation, the parasite of agriculture. In from four to six weeks after being laid, the little larvæ are hatched (Fig. 433), and immediately attack the roots of vegetables. Theyhave a hard and horny head, and slender black legs, longer than in any other species ofScarabæides. Their body is composed of a whitish pulp under a transparent skin; the head and the mouth have a reddish tinge. The length of their existence in this state is three, sometimes four years. From the egg laid in the month of June is hatched a larva, in the month of July. It increases in size during the last six months of the year, and continues to do so during the two following years, changing its skin many times during the period. Towards the end of the third year it changes into a pupa, after having surrounded itself with a cocoon consolidated with a glutinous froth and some threads of silk. The pupa (Fig. 434) is of a pale russety yellow, with two little points at the extremity of its body; the elytra and the wings, lying down, cover the legs and the antennæ.Fig. 433.—Larva of the Cockchafer (Melolontha vulgaris).Fig. 434.—Pupa of the Cockchafer (Melolontha vulgaris).Towards the end of October the perfect insect is already marked out, but it is still soft and weak. It passes the winter in its hiding-place, hardens and becomes coloured at the end of the winter, and shows itself by degrees on the surface of the ground. In the month of April, three years after its birth, the cockchafer emerges from the earth, and commences its attack on the leaves of trees. This long duration of the development of the insect explains why we do not see them every year in the same number. When they have once appeared in great quantities, it is not for three years afterwards that we need expect to see their progeny again in proportionate numbers. It is, then, every three years that we have acockchafer yearlike 1865, but in the intermediate years they are never very abundant. For the first year the little larvæ do not eat much. They feed then principally on fragments of dung, and on vegetable detritus, and keep together in families. In winter they bury themselves deeply, so as to be secure against frost and floods. Next spring the want of a greater abundance of food forces them to disperse. They then make subterranean galleries in all directions, without, however, going far from the place where they were hatched. They begin attacking the roots which they find within their reach; the damage they do increasing with their size and the strength of their mandibles. Among roots, they seem to prefer those of the strawberry and of rose-trees; but they do not despise other vegetables, and attack legumes and cereals as well as bushes and plants. The ravages which they occasion are sometimes incalculable; market gardens are sometimes entirely devastated. Fields of lucerne have been seen partially destroyed by them; meadows of great extent lose their pasturage; oat fields die off before they have come to maturity; and many of the ears of corn fall before they are cut.In proportion as they increase in age and in strength—especially in their last year—do they attack also ligneous vegetation. When they have gnawed away the lateral roots of a young tree, the new shoots corresponding to them dry up. The larvæ then attack the principal root, and thus bring about the death of the tree. There will be found round the roots of trees thus attacked immense numbers of these worms. M. Deschiens relates that he had seen six hectares of acorns, sown three times in the space of five years with a perfect result, entirely destroyed as many times by the larvæ of the cockchafer. A nurseryman of Bourg-la-Reine suffered, in 1854, from the ravages of these terrible larvæ, losses which he estimated at 30,000 francs. Others only preserved about a hundredth part of their plants. In Prussia they destroyed, in 1835, a considerablenursery of trees in theInstitut Forestier. In the forests of Kolbetz more than a thousand measures of wild pines were destroyed in the same way.We shall not, then, be surprised to learn that the thunders of excommunication were formerly launched at the cockchafers, as they were also at the caterpillars and the locusts. We do not know whether this had much impression upon them. In 1479, the cockchafers having occasioned a famine in the country, were cited before the ecclesiastical tribunal of Lausanne. The advocate (Fribourg) who defended them, did not find, doubtlessly, in the resources of his eloquence arguments powerful enough in their favour; for the tribunal, after mature deliberation, condemned the accused troop, and sentenced them to be banished from the territory. But it is not enough to pass a sentence—there must also be the means of putting it in execution; and these were wanting to the tribunal of Lausanne. And so the condemned cockchafers continued to live on Swiss land, without appearing mindful of the condemnation which had been fulminated against them.The larvæ of the cockchafer are not easily destroyed. They successfully resist those scourges which one fancies must harm them. Thus, the inundation which devastated the banks of the Saône, fifteen years ago, had no effect on them. The land and meadows, which had remained for from four to five weeks under water, were none the more rid of them. The only circumstance which is really hurtful to them, and to the adult cockchafer, is late frost in the months of April and May. When these frosts come after mild weather, they surprise the larvæ at the surface of the soil, and kill them. Unfortunately, the same causes do harm to the plants which have already begun to spring up. Nature has not, then, sufficiently provided the means of destroying these mischievous beings. One would say that she had not foreseen their extraordinary multiplication, which has been, we must confess, encouraged by agriculture and by the cultivation of the land.Animals do not contribute much towards limiting the number of cockchafers, although the latter are not wanting in natural enemies. Among insects, it is the large species ofCarabuswhich search after the larvæ as well as the adult cockchafers. TheCarabus auratusattacks them with great coolness. M. Blanchard saw a carabus seize a cockchafer in the middle of the road, open its belly with its mandibles, and devour its intestines. The cockchafer tossed about from one side to the other, and even walked, while it was undergoing its cruel punishment; and theCarabusfollowed it without interruptingits work. Some reptiles, many carnivorous animals, such as the shrew-mouse, pole-cats, weasels, rats, and certain birds, especially the night-birds, prey upon the cockchafer and its larvæ. Ravens and magpies, which are seen going from clod to clod, make savage but insufficient war against them. In fact, all these animals together do not destroy the hundredth part of the cockchafers which are born every year.As an example which will show the extent of the evil, a field of 29 acres was ploughed up into 72 furrows. At the first ploughing were gathered 300 larvæ per furrow; at the second, 250; at the third, 30 more; which amounted to 600 per furrow, and to 43,200 in all. Man, who is the victim of these ravages, has been necessarily obliged to think of a means of destroying this enemy. Manyinfalliblemeans have been proposed, which have, however, given no result. Prizes have been offered, but the evil has not diminished. Here are a few of the processes recommended.Immediately after the ploughing, you must turn into the field infested by the larvæ a flock of turkeys, to whom it will be a great treat to devour them, or else you must sow in the field rape-seed, very thickly, which you must then bury by a very deep ploughing, when it is as high as your hand. Colewort, it is said, kills the larvæ, while it at the same time manures the soil. Or again, you must plough up the land on the approach of hard frosts, to expose the worms to the cold. Lastly, you can water the field with oil of coal, or sprinkle it with ashes of boxwood. All these are expensive. The simplest means are here the best. It is better to depend upon labour than destructive substances, whose employment always presents inconveniences. Considering the difficulties which oppose themselves to us in our search after larvæ, we had better collect them in their adult state by violently shaking the branches of the trees on which they doze during the day, and then kill them in some way or other, thus destroying from twenty to forty eggs with each female. A general cockchafer hunt, rendered obligatory by a law, and encouraged by prizes, would be the only efficacious means of opposing a pest which costs agriculture many millions. This means would also be less costly than the turning up of the land concealing the larvæ, when it is remembered that they prefer land in full bearing.In 1835 the General Council of La Sarthe voted a sum of 20,000 francs for a cockchafer hunt. Nearly 600,000 litres were delivered in, thanks to a prize of three centimes per litre. As a litre contains about 500 cockchafers, there were thus destroyed about 300,000,000 of them. It is true that M. Romieu, thenPrefect of La Sarthe, who was the principal promoter of this excellent measure, became food for the wit of the newspapers, and was represented dressed like a cockchafer in theCharivari. Derision and ridicule are too often the reward of useful ideas. In Switzerland were taken, in 1807, more than 150,000,000 of these insects. But these isolated measures were useless in producing a durable result.It has been tried to make use of cockchafers in industrial arts. According to M. Farkas, they have succeeded, in Hungary, by boiling them in water, in extracting from them an oil, which is used to grease the wheels of carriages; and, according to M. Mulsant, the blackish liquid which is contained in the œsophagus may be used for painting. But the produce arising from these industrial occupations is not considerable enough to ensure them a certain extension, which is to be regretted, for agriculture would thus be rid of one of its most formidable scourges. Poultry are sometimes fed on these insects; pigs are also very fond of them.TheMelolontha Hippocastanidiffers from the common species in having black legs. TheMelolontha fullo, twice as large as the common species, is variegated with tawny and white. It is met with on the sea-coasts, and on the downs of the north and south of France, as its larvæ feed on the roots of maritime plants.Among the genera very near to the cockchafer we will mention the littleRhizotrogus, light-coloured and hairy, which flies in the evening in the meadows, and theEuchloras, orAnomalas, of splendid metallic colours. TheAnomala vitisis an insect of about half an inch long, of a beautiful green, bordered by yellow, with the elytra deeply furrowed. It sometimes causes extensive ravages in the vineyards.After theCetoniadæand the Cockchafers, we come to theScarabæidæ, properly so called. TheOryctes nasicornis(Fig. 435) is very common all over Europe. It is about an inch long, of a chestnut-brown, and perfectly smooth. The male has on the head a horn, which is wanting in the female (Figs.436,437). Its larva, which is a great whitish worm, larger than that of the cockchafer, lives in rotten wood and in the tan which is employed in hot-houses and in garden-frames. They were to be found by hundreds in the old hot-houses of the Jardin des Plantes at Paris. The market-gardeners, who employ the tannin of the oak bark, have rendered this Coleopteron very common in the environs of that capital.Fig. 438represents an exotic species, theXylotrupes dichotomus.Among the trueScarabæiwe meet with many species of giganticsize, especially in America.Dynastes Hercules, a great insect of a fine ebony black, with its elytra of an olive grey, is not rare in the Antilles. Its thorax is prolonged into a horn as long as its body, and bent round at the extremity; its head has also a long horn standing erect. The females want these appendages.Fig. 439represents theGolofa clavigerof Guyana.Fig. 435.—Oryctes nasicornis, male.Fig. 436.—Head of Oryctes nasicornis, male.Fig. 436.—Head of Oryctes nasicornis, male.Fig. 437.—Head of Oryctes nasicornis, female.Fig. 435.—Oryctes nasicornis, male.Fig. 437.—Head of Oryctes nasicornis, female.TheGeotrupesare insects almost as common as the chafers. As their name reminds us, they make holes in the ground, which they scoop out, particularly in meadows, under cow-dung which has growndry on the surface. It is under the excrements of ruminating animals and horses that they must be looked for. They fly especially at night, and may be seen buzzing about on fine summer evenings in the vicinity of dung heaps.Fig. 438.—Xylotrupes dichotomus.TheGeotrupes stercorarius, the Shard-born Beetle, Clock, or Dumbledor, is of a brilliant bluish black, and attains to a length of about two-thirds of an inch. We may consider this Coleopteron as a useful auxiliary of man in ridding the soil of excrementitious matter. The genusTrox, which belongs to the same group, generally inhabits sandy countries, and has its body nearly always covered with earth or dust; it lives on vegetable substances, or on animal matter in a state of decomposition. The habits of the genusCoprisresemble those ofGeotrupes; they live in excrement. The form of their clypeus, broad, rounded, without teeth, and advancing over the mouth, suffices to distinguish the kindred species. In the environs of Paris and in England theCopris lunarisis found. The larvæ of these insects form a cocoon composed of earth and dung, before transforming themselves into pupæ; this cocoon is more or less round, and acquires a great hardness.Fig. 439.—Golofa claviger.The species of the genusAteuchuscollect portions of excrement, which they make up into balls, and roll till they are as perfectly rounded as pills, and in which they lay their eggs. This habit has gained for these insects the name of pill-makers. Their hind legs seem to be particularly adapted for this operation, for they are very long and somewhat distant from the other legs, which gives to theAteuchia strange appearance, and makes it hard work for them to walk. They walk backwards and often fall head over heels. They are generally seen on declivities exposed to the greatest heat of the sun, assembled together to the number of four or five, occupied in rolling the same ball; so that it is impossible to know which is the real proprietor of this rolling object. They seem not to know themselves; for they roll indifferently the first ball which they meet with, or near which they are placed.Fig. 440.—Scarabæus (Golofa) Porteri.Fig. 440.—Scarabæus (Golofa) Porteri.Fig. 441.—Scarabæus enema, or Enema infundibulum.Fig. 441.—Scarabæus enema, or Enema infundibulum.TheAteuchiare large flat insects, with a broad-toothed clypeus; they all belong to the Ancient Continent. The type of the genus is theAteuchus sacer(Fig. 442), the Sacred Scarabæus of the Egyptians. This insect is black, and attains to a length of a little less than an inch. It is to be found commonly enough in the south of France, in the whole of southern Europe, Barbary, and Egypt. The paintings and amulets of the ancient Egyptians very often represent it, and sometimes give it a gigantic size. It is, doubtless, then, this species which was an object of veneration with the Egyptians.There exists another species, which is always represented as of a magnificent golden green, and to which Herodotus also attributes this colour. As it was not to be found in Egypt, it was thought for a long while that the Egyptians had painted the black species of a more splendid colour in order to pay it homage. But in 1819 M. Caillaud actually found at Meroe, on the banks of the White Nile, theAteuchus Ægyptiorum, which resembles theAteuchus sacermuch in colour, but has a golden tint. Since then it has also been brought from Sennaar. The two species were both probably sacred. Hor-Apollon, the learned commentator on Egyptian hieroglyphics, thinksthat this people, in adopting the scarabæus as a religious symbol, wished to represent at once,a unique birth—a father—the world—a man. Theunique birthmeans that the scarabæus has no mother. A male wishing to procreate, said the Egyptians, takes the dung of an ox, works it up into a ball, and gives it the shape of the world, rolls it with its hind legs from east to west, and places it in the ground, where it remains twenty-eight days; the twenty-ninth day it throws its ball, now open, into the water, and there comes forth a male scarabæus. This explanation shows also why the scarabæus was employed to represent at the same time afather,a man, andthe world. There were, however, according to the same author, three sorts ofScarabæi: one was in the shape of a cat, and threw out brightly shining rays (probably the Golden Scarabæus,Ateuchus Ægyptiorum); the two others had horns; their description seems to refer to aCoprisand aGeotrupes.As other remarkable species ofScarabæiwe represent theScarabæus enema(Fig. 441), with strong horns, theMegacerus chorinæus(Fig. 443), theMegalosoma anubis(Figs.444and445), and theDynastes Hercules(Fig. 446).The last family of theScarabæidæcontains theLucanidæ, or Stag Beetles. These Coleoptera are of great size, and their head is armed with enormous robust mandibles, which give them a ferocious air, which their inoffensive habits do not in any way justify. They live in half-rotten trees, the destruction of which they accelerate. Their mandibles, of such prodigious size only in the male, are of more inconvenience to them than they are of use, as they impede their flight. Their strength enables them to raise considerable weights, but they make no other use of them than to show their strength, which is enormous. They do not attack other insects, and live only on vegetable juices.The common Stag Beetle (Figs. 447[121]and 448) attains to a length of two inches, or more, including its mandibles, and is of a dark brown chestnut colour. They are met with during the months of May, June, and July, in large forests, climbing along trees and hooking themselves on to the trunks by their mandibles. Charles De Geer says that the Stag Beetle imbibes the honeyed liquid which is found on oak trees, a tree it particularly seeks after, which has caused it tobe called in SwedishEk-Oxe(Oak ox). It is supposed that it eats the leaves also. It sometimes attacks insects. Westwood says that it has been seen to descend from a tree carrying a caterpillar in its mandibles. Swammerdam had one which followed him like a dog when he offered it honey. They only fly in the evening, holding themselves nearly straight, so as not to see-saw. Their larvæ—which are whitish, with russety heads, live in the interior of trees, their existence in that state lasting nearly four years. Many naturalists think that the larva of theLucanuswas theCossusof the Romans, which figured on the tables of the rich patricians, and particularly of Lucullus.
IX.
COLEOPTERA.
In collections of insects the Coleoptera almost always occupy the principal place. They are sought after by collectors on account of the brightness of their colours, of the solidity of their integuments, and the facility with which they can be preserved. This circumstance has contributed much to give to the Coleopterous Order marked preponderance in the immense series of insects. Many more have been collected than any one has as yet been enabled to describe; and the collections are encumbered with species of which no naturalist has yet given an account.
Admitting that the first-rate collections contain each about 25,000 perfectly distinct species, and that a certain fraction of these treasures is peculiar to each collection, M. Blanchard came to the conclusion that we must estimate the number at more than 100,000 of the species of Coleoptera which would be obtained if the different entomological collections of France, England, and Germany were put together. But every day we see arriving from different regions of the globe new riches, hardly dreamt of up to that time; and it is not only the small species, but the larger and more beautiful also, which furnish their contingent. It may, then, be believed that, if the entire surface of the earth were carefully explored, we should obtain an incalculable number of Coleoptera, having sufficient characteristics to constitute distinct species or kinds.
The Coleoptera (from [Greek: koleos], a sheath, and [Greek: pteron], a wing) are insects with four wings. The anterior wings, orelytra, are not used in flying; they are sheaths, more or less hard, sometimes varied with bright colours, and never crossing over each other. The posterior wings are membranous, presenting a ramification of veins, and usually folding up under theelytra, which protect them when at rest. The mouth of Coleoptera is provided with mandibles, with jaws, and two quite distinct lips, and is suited for mastication. They undergo complete metamorphosis. After an existence of greater or less extentin the larva state (in the case of the cockchafer three years), the insect changes into a pupa, which remains in a state of complete immobility. After a certain time, the pupa bursts its envelope and assumes the form of a perfect insect. The Coleoptera presents the utmost variety of habits as regards their habitations and food. One does not find in this Order those admirable instincts, those manifestations of intelligence, which bring certain Hymenoptera near to those beings which are highest in the animal scale; but they offer peculiarities very well deserving serious and profound study. Some are carnivorous, and thus they are useful to man in destroying other noxious insects, which they seek on the ground, on low plants, on trees, and even in the depths of the waters. Many of these Coleoptera feed on animal matter in a state of putrefaction. We may look on them as useful auxiliaries: they are Nature's undertakers.
A great number live in the excrements of animals. The dung of oxen, buffaloes, and camels afford shelter to Coleoptera of different families, which thus live on vegetable matter more or less animalised. Others attack skins and dried animals in general; and some are the pest of entomological collections. Lastly, immense legions of Coleoptera are phytophagous; that is to say, they attack roots, bark, wood, leaves, and fruits, and cause much annoyance to the agriculturist. Above all, the larvæ are to be dreaded. Those which live in wood may in a few years occasion the loss of trees, vigorous and full of life; or completely destroy the beams of a building. Certain larvæ, such as those of the cockchafer, eat away the roots of vegetables, and so destroy the harvests. Others, lastly, devour the leaves and the stalks of plants, attack the flowers in the gardens, or the corn in the barns; and so man makes desperate war against them.
In the immense variety of known Coleoptera we must be contented to choose those types which are most prominent and most characteristic. We will begin with theScarabæides, with their heavy compact body, and short antennæ, terminated by a foliaceous club. It is to this tribe that belongs the beautiful Rose Beetle (Cetonia aurata), which lives on roses; the Cockchafer (Melolontha vulgaris); theScarabæusof the Egyptians; &c.
This is the most interesting tribe of the whole Order Coleoptera. It corresponds with the great division of theLamellicornesof Latreille. This name ofLamellicorneswas intended to remind us of the arrangement into laminæ, more or less close together, of the club of the antennæ of these insects. ManyScarabæihave their mandibles membranous, or at least partially so, and always small. This peculiarity corresponds to their habits. Never, indeed, have they totriturate hard bodies; they all feed either on flowers, on leaves, or on stercoraceous matter. Their larvæ resemble each other much, even those of families very widely differing from each other in the perfect state. They are large, whitish worms, with diaphanous skins, scaly heads, furnished with toothed mandibles, living in the ground or in rotten wood. The pupæ are fat and stumpy, and they already show the features of the perfect insect. They make a chamber in which to undergo their changes. They remain generally three years in the larva state. The duration of the pupa is very short, as also is that of the perfect insect. The differences of the sexes are often very marked on the exterior, by protuberances, horns, &c., which constitute the distinctive ornament of the males.
In the group ofScarabæideswe shall have to speak, above all, of theCetoniadæ, the Chafers, and theScarabæiproperly so called. The familyCetoniadæis one of the most remarkable, on account of the beauty of the insects which compose it and of the richness of their metallic lustre, some being of great splendour, and others having velvety tints. The larvæ live in wood in a state of decomposition; the perfect insects frequent flowers, and like the sun.
Fig. 423.—Rose Beetle (Cetonia aurata).
This family contains a great number of species, the type of which is the Rose Beetle (Cetonia aurata), of a beautiful green colour shot with gold, with transverse whitish lines. The rose beetle frequents roses especially, of which it eats the petals and the stamens. It is theGolden Melolonthaof Aristotle, who tells us that this unfortunate insect shared with the cockchafer the privilege of amusing children. TheCetoniaflies by day and by night, making use of its inferior wingswithout opening the elytra (Fig. 423). When seized, it pours out from the extremity of its abdomen a fœtid liquid, the only means of defence the poor insect possesses. The larva (Fig. 424) much resembles the larva of the cockchafers, but the legs are shorter. It is found in rotten wood, and often in ants' nests. When it has acquired its full development it makes a cocoon of an oval form (Fig. 424), in which it transforms itself into a pupa; the cocoon is composed of bits of wood agglomerated with a silky matter which the larva secretes.
Fig. 424.—Larva and cocoon of the Rose Beetle.
The larva of theCetonia splendidula—which is the most magnificent found in France—is met with sometimes in the nests of wild bees. In Russia the rose beetle is considered a very efficacious remedy for hydrophobia. In the governorship of Saratow, which is traversed by the Volga, hydrophobia is very frequent, on account of the heats which reign during the whole summer in its arid steppes. The inhabitants, incessantly exposed to be bitten by mad dogs, have tried in succession a great many preparations to remedy the results of these terrible accidents. It appears that theCetonia, dried and reduced to powder, has produced on many occasions good effects. This is the recipe which an inhabitant of Saratow published in a Russian journal—adding, that he had employed it for thirty years, that not one of the patients treated by him had died, and that his remedy could be employed with success in all the phases of the disease:—In spring they search at the bottom of the nests of the wood ant for certain white larvæ, which they carefully preserve in a pot, together with the earth in which they were found, till the moment of their metamorphosis, which takes place in the month of May. The insect, which is the common rose beetle, is killed, dried,and kept in pots hermetically sealed, so that it may preserve the strong odour which it exhales in spring, which seems to be a necessary condition of the remedy proving efficient. When a case of hydrophobia presents itself, they reduce to powder some of these, and spread this powder on a piece of bread-and-butter, and make the patient eat it. Every part of the insect must enter into the composition of this powder, which, for this reason, cannot be very fine. During the whole time a patient is under treatment he must avoid drinking as much as possible, or, if his thirst is very great, he must only drink a little pure water; but he may eat. Generally, this remedy produces sleep, which may last for thirty-six hours, and which must not be disturbed. When the patient wakes, he is, they say, cured. The bite must be treated locally with the usual surgical appliances.
As to the dose of the remedy, that depends on the age of the patient and the development of the disease. They give, to an adult, immediately after the bite, from two to three beetles; to a child, from one to two; to a person in whom the disease has already declared itself, from four to five. Given to a person in good health, the remedy, however, would not be the least dangerous. In cases in which the symptoms of hydrophobia show themselves some days after the employment of the remedy, they recommence the treatment. They have also tried to prepare this remedy with insects collected not in their larvæ but in the imago state, by catching them on flowers, and it seems that these attempts have succeeded. According to M. Bogdanoff, in many governorships of the south of Russia the lovers of sporting are in the habit of making their dogs from time to time swallow (as a preservative) half of aCetoniawith bread or a little wine. Every one in those countries is persuaded of the efficacy of this means for stopping the development of the disease. One ought not, perhaps, to reject a belief so widespread and deeply rooted without some experiments to guarantee us in doing so, for medicine does not yet possess any remedy against hydrophobia: it might not then be useless to try this.
Two smaller species than the rose beetle, theCetonia sticticaand theCetonia hirtella, which has yellowish hairs, live on the flowers of thistles. Western Africa, the Cape, Madagascar, &c., are very rich in species ofCetoniæ. Among theCetoniadæis the genusGoliathus, gigantic insects which inhabit Africa. Their total length sometimes attains from three to five inches. Their colours are generally a dull white or yellow, which has nothing metallic about it, with spots of a velvety black—these are due to a sort of down of an extreme thinness, and which very easily comes off. The head of these enormous Coleoptera is generally cut or scooped out, and is adorned sometimes with one or two horns. Their legs, strong and robust, are armed with spurs, and sometimes present on their exterior sharp indentations, which give to these insects a crabbed physiognomy, which their inoffensive habits are far from justifying. All these horns, and all these teeth, which look so terrible, are nothing, in fact, with a great number of these insects, but simple ornaments. They compose the picturesque uniform of the males. They are equivalent to the bear-skin caps, the flaming helmets, and the bullion-fringed epaulettes of our soldiers. The dress of the femaleGoliathusis much more modest, as is becoming to the sex. We here represent theGoliathus Derbyana(Fig. 426) and Polyphemus (Fig. 427).
Fig. 425.—Cetonia argentea.Fig. 425.Cetonia argentea.
The Goliaths were formerly excessively rare in collections, and of a price inaccessible to ordinary amateurs—one single specimen costing as much as twenty pounds. But for some time the Goliaths of the coast of Guinea and of Cape Palmas have been sold to European amateurs at a modest price, thanks to those travellers who, after the example of Dr. Savage, have collected them by hundreds in the countries which produce them. These enormous Coleoptera are seen on the coast of Guinea fluttering about at the top of trees, the flowers of which they are seeking after. To catch them the trees are felled or else they are shot at with a gun loaded with sand, as is also done for the humming-birds. The species which Dr. Savage made common is theGoliathus cacicus, of which we represent the male and female (Figs. 428, 429). It is met with on the coast of Guinea. TheGoliathus Druryi(Fig. 430) inhabits Sierra Leone, on the west coast of Guinea. The numerous expeditions which are at the present moment being made into the interior of Africa will not fail to increase the number of species of these splendid insects, which are the ornament of all collections.
The group of theTrichiadæ, which has in this country and in France a few representatives, is very nearly the same as that of theCetoniadæ. TheTrichiadæhave the elytra shorter, the abdomen bigger, and the legs more slender. TheTrichius fasciatus, which is black, and covered with an ashy down, with the elytra yellow, and with three black bands, is to be met with in quantities on the garden rose-tree, in the months of June and July. The larvæ live in the interior of old beams of wood, respecting their surfaces. In a garden, at a few leagues from Paris, a little wooden bridge had been built. It seemed on the outside to be in a perfect state of preservation. Nothing on the exterior would have led one to think it was possible for the oak timbers which composed it to break down. A good many of them, however, broke suddenly. It was then seen that the wood had been scooped out right up to the surface, which was nothing better than a thin sheet, of an imperceptible thinness. All the interior was full ofTrichii, in the states of larva, pupa, and perfect insect.
TheTrichius fasciatus, sometimes called the Bee Beetle, is verycommon in the environs of Paris. Geoffroy has described it under the rather quaint name of the "Livrée d'Ancre," because the Marquis of Ancre made his servants wear yellow coats, bordered by braid alternately crossed with green and yellow.
Fig. 428.—Goliathus cacicus, male.Fig. 428.—Goliathus cacicus, male.
Fig. 429.—Goliathus cacicus, female.Fig. 429.—Goliathus cacicus, female.
TheOsmoderma eremitais a large insect, of purple colour,formerly common in the environs of Paris, and which, now-a-days, cannot be found nearer than Fontainebleau. One must look for them in earth which fills up the cavity of old willows or of pear trees. The smell of Russia leather, or of plum, which it exhales, has caused it to be called, in some places, the Plum-tree Beetle.
Fig. 430.—Goliathus Druryi (natural size).Fig. 430.—Goliathus Druryi (natural size).
TheGnorimus nobilismuch resembles the rose beetle, and is found on elder flowers, the whiteness of which this golden insect relieves. One species, much smaller, only one or two lines long, is theValgus hemipterus, which is often met with in spring, in the dust of the roads. The female has a long auger, which enables it to deposit its eggs in rotten wood. Dumeril has described at length the singular movements of this little insect:—The jerking and, as it were convulsive, movements by which it transports itself from one place to another; its tottering attitude, resulting from the excessive length of its hind legs; the vertical carriage of these, which, by their singular direction, interfere much with the walking, which is directed by the other legs. One should, above all, notice the artifice which theValgusemploys, as indeed do many Coleoptera, to escape from his persecutors, by counterfeiting death. As soon as it is seized by any enemy, its members stiffen and become motionless. The body, abandoned to itself, lies unevenly on whatever side it falls, for its legs no longer bend; if you bend them over, they remain in the inclination given to them. Nothing then betrays life in this little dry and slender being, frozen with fear, and imitating death, without, perhaps, being aware itself of what it is doing.
We must still further mention here theIncas—beautiful insects of the same group, which are met with in South America, and whose males have an extraordinary head. They fly during the day round the great trees on which they live.Fig. 431represents theInca clathrata.
The most commonly-known insect of the family with which we are now occupied is the cockchafer. The French word for cockchafer,hanneton, according to M. Mulsant, comes from the Latin,alitonus(which has sonorous wings), which first becamehalleton. Linnæus gave them first the name ofMelolontha, which they probably had among the Greeks, and which seems to be the case from this passage in Aristophanes, in his comedy of "The Clouds:"—"Let your spirit soar," says the Greek author, "let it fly whither it lists, like the Melolontha tied with a thread by the leg." We see that the habit of martyrising cockchafers is of very early date. The Common Cockchafer (Fig. 432) is one of the greatest pests to agriculture. In its perfect state it devours the leaves of many trees, principally thoseof the elm; and so children call the fruit of the elm-tree by the name of "Pains d'Hanneton." But the destruction which they occasion in their perfect state is little when compared with that which is caused by their larvæ—those white grubs so dreaded by agriculturists.
Fig. 431.—Inca clathrata.
Cockchafers make their appearance from the month of April, if the season is warm. But it is in the month of May that they show themselves in great quantities; and so they are called in GermanyMaikäfer(Maychafer). They are met with also in June. The duration of their life as a perfect insect is six weeks. They fear the heat of the day and the bright sunshine, so, during the day, they remain hooked on to the under surface of leaves. It is only early in the morning, and at sunset, that one sees the cockchafers fluttering round the trees which they frequent. They fly with rapidity, producing a monotonous sound by the friction of their wings. But the cockchafer steers badly when it flies; it knocks itself at each instant against obstacles it meets with. It then falls heavily to the ground, and becomes the plaything of children, who are constantly on the look-out for them. There is a saying, "Étourdi comme un hanneton." What contributes still more to render the flight of these insects heavy and sustained only for a short time together is that they are obligedto inflate themselves like balloons in order to rise into the air: it is a peculiarity which they share with the migratory locust. Before taking its flight, the cockchafer agitates its wings for some minutes, and inflates its abdomen with air. The French children, who perceive this manœuvre, say that the cockchafer "compte ses écus" (is counting its money), and they sing to it this refrain, which has been handed down for many generations:—
"Hanneton, vole, vole,Va-t'en à l'école."
A variation which we hear in the western provinces of France is the following:—
"Barbot, vole, vole, vole,Ton père est à l'école,Qui m'a dit, si tu ne voles,Il te coupera la gorgeAvec un grand couteau de Saint-George."
Fig. 432.—CockchaferFig. 432.—Cockchafer (Melolontha vulgaris).
During the day the cockchafers remain under the leaves in a state of perfect immobility; for the heat which gives activity to other insects, seems, on the contrary, to stupefy them, and it is during the night only that they devour the leaves of elms, poplars, oaks, beech, birch-trees, &c. In years when their number is not very great, one hardly perceives the damage done by them; but at certain periods they appear in innumerable legions, and then whole parts of gardens or woods are stripped of their verdure, and present, in the middle of the summer, the appearance of a winter landscape. The trees thus stripped do not in general die; but they recover their former vigour with difficulty, and, in the case of orchard trees, remain one or two years without bearing fruit. It is principally the trees skirting woods, and situated along cultivated fields, which are exposed to the ravages of the cockchafer, because the larvæ of these insects are developed in the fields. In the interior of forests they are never met with in great numbers.
In certain years cockchafers multiply in such a frightful manner that they devastate the whole vegetation of a country. In the environs of Blois 14,000 cockchafers were picked up by children in a few days. At Fontainebleau they could have gathered as many in a certain year in as many hours. Sometimes they congregate in swarms, like locusts, and migrate from one locality to another, when they lay waste everything. To present an idea of the prodigious extent to which cockchafers increase under certain circumstances,we will give a few statistics:—In 1574, these insects were so abundant in England that they stopped many mills on the Severn. In 1688, in the county of Galway, in Ireland, they formed such a black cloud that the sky was darkened for the distance of a league, and the country people had great difficulty in making their hay in the places where they alighted. They destroyed the whole of the vegetation in such a way that the landscape assumed the desolate appearance of winter. Their voracious jaws made a noise which may be compared to that produced by the sawing of a large piece of wood, and in the evening the buzzing of their wings resembled the distant rolling of drums. The unfortunate Irish were reduced to the necessity of cooking their invaders, and, for the want of any other food, of eating them. In 1804, immense swarms of cockchafers, precipitated by a violent wind into the Lake of Zurich, formed on the shore a thick bank of bodies heaped up one on the other, the putrid exhalations from which poisoned the atmosphere. On May 18, 1832, at nine o'clock in the evening, a legion of cockchafers assailed a diligence on the road from Gournay to Gisors, just as it was leaving the village of Talmontiers; the horses, blinded and terrified, refused to advance, and the driver was obliged to return as far as the village, to wait till this new sort of hail-storm was over. M. Mulsant, in his "Monographie des Lamellicornes de la France," relates that in May, 1841, clouds of cockchafers traversed the Saône, from the south-east in the direction of the north-west, and settled in the vineyards of the Mâconnais. The streets of the town of Mâcon were so full of them, that they were shovelled up with spades. At certain hours, one could not pass over the bridge without whirling a stick rapidly round and round, to protect oneself against their touch.
XI.—A Diligence surrounded by a Cloud of Cockchafers.
The coupling takes place towards the end of May, after which the males die; the females only surviving them from the time necessary to ensure the propagation of the species. The number of eggs which a female lays is from twenty to thirty. With her front leg she hollows out a hole in the ground from two to four inches in depth, and deposits her eggs, of a yellowish white and of the size of hemp-seed, therein. Her instinct leads her to choose soft, light, and well-manured soils, which are, at the same time, the best ventilated and the most fertile. We may conclude from this that cultivation and labour have made the cockchafer more common than it was formerly. It is the child of civilisation, the parasite of agriculture. In from four to six weeks after being laid, the little larvæ are hatched (Fig. 433), and immediately attack the roots of vegetables. Theyhave a hard and horny head, and slender black legs, longer than in any other species ofScarabæides. Their body is composed of a whitish pulp under a transparent skin; the head and the mouth have a reddish tinge. The length of their existence in this state is three, sometimes four years. From the egg laid in the month of June is hatched a larva, in the month of July. It increases in size during the last six months of the year, and continues to do so during the two following years, changing its skin many times during the period. Towards the end of the third year it changes into a pupa, after having surrounded itself with a cocoon consolidated with a glutinous froth and some threads of silk. The pupa (Fig. 434) is of a pale russety yellow, with two little points at the extremity of its body; the elytra and the wings, lying down, cover the legs and the antennæ.
Fig. 433.—Larva of the Cockchafer (Melolontha vulgaris).
Fig. 434.—Pupa of the Cockchafer (Melolontha vulgaris).
Towards the end of October the perfect insect is already marked out, but it is still soft and weak. It passes the winter in its hiding-place, hardens and becomes coloured at the end of the winter, and shows itself by degrees on the surface of the ground. In the month of April, three years after its birth, the cockchafer emerges from the earth, and commences its attack on the leaves of trees. This long duration of the development of the insect explains why we do not see them every year in the same number. When they have once appeared in great quantities, it is not for three years afterwards that we need expect to see their progeny again in proportionate numbers. It is, then, every three years that we have acockchafer yearlike 1865, but in the intermediate years they are never very abundant. For the first year the little larvæ do not eat much. They feed then principally on fragments of dung, and on vegetable detritus, and keep together in families. In winter they bury themselves deeply, so as to be secure against frost and floods. Next spring the want of a greater abundance of food forces them to disperse. They then make subterranean galleries in all directions, without, however, going far from the place where they were hatched. They begin attacking the roots which they find within their reach; the damage they do increasing with their size and the strength of their mandibles. Among roots, they seem to prefer those of the strawberry and of rose-trees; but they do not despise other vegetables, and attack legumes and cereals as well as bushes and plants. The ravages which they occasion are sometimes incalculable; market gardens are sometimes entirely devastated. Fields of lucerne have been seen partially destroyed by them; meadows of great extent lose their pasturage; oat fields die off before they have come to maturity; and many of the ears of corn fall before they are cut.
In proportion as they increase in age and in strength—especially in their last year—do they attack also ligneous vegetation. When they have gnawed away the lateral roots of a young tree, the new shoots corresponding to them dry up. The larvæ then attack the principal root, and thus bring about the death of the tree. There will be found round the roots of trees thus attacked immense numbers of these worms. M. Deschiens relates that he had seen six hectares of acorns, sown three times in the space of five years with a perfect result, entirely destroyed as many times by the larvæ of the cockchafer. A nurseryman of Bourg-la-Reine suffered, in 1854, from the ravages of these terrible larvæ, losses which he estimated at 30,000 francs. Others only preserved about a hundredth part of their plants. In Prussia they destroyed, in 1835, a considerablenursery of trees in theInstitut Forestier. In the forests of Kolbetz more than a thousand measures of wild pines were destroyed in the same way.
We shall not, then, be surprised to learn that the thunders of excommunication were formerly launched at the cockchafers, as they were also at the caterpillars and the locusts. We do not know whether this had much impression upon them. In 1479, the cockchafers having occasioned a famine in the country, were cited before the ecclesiastical tribunal of Lausanne. The advocate (Fribourg) who defended them, did not find, doubtlessly, in the resources of his eloquence arguments powerful enough in their favour; for the tribunal, after mature deliberation, condemned the accused troop, and sentenced them to be banished from the territory. But it is not enough to pass a sentence—there must also be the means of putting it in execution; and these were wanting to the tribunal of Lausanne. And so the condemned cockchafers continued to live on Swiss land, without appearing mindful of the condemnation which had been fulminated against them.
The larvæ of the cockchafer are not easily destroyed. They successfully resist those scourges which one fancies must harm them. Thus, the inundation which devastated the banks of the Saône, fifteen years ago, had no effect on them. The land and meadows, which had remained for from four to five weeks under water, were none the more rid of them. The only circumstance which is really hurtful to them, and to the adult cockchafer, is late frost in the months of April and May. When these frosts come after mild weather, they surprise the larvæ at the surface of the soil, and kill them. Unfortunately, the same causes do harm to the plants which have already begun to spring up. Nature has not, then, sufficiently provided the means of destroying these mischievous beings. One would say that she had not foreseen their extraordinary multiplication, which has been, we must confess, encouraged by agriculture and by the cultivation of the land.
Animals do not contribute much towards limiting the number of cockchafers, although the latter are not wanting in natural enemies. Among insects, it is the large species ofCarabuswhich search after the larvæ as well as the adult cockchafers. TheCarabus auratusattacks them with great coolness. M. Blanchard saw a carabus seize a cockchafer in the middle of the road, open its belly with its mandibles, and devour its intestines. The cockchafer tossed about from one side to the other, and even walked, while it was undergoing its cruel punishment; and theCarabusfollowed it without interruptingits work. Some reptiles, many carnivorous animals, such as the shrew-mouse, pole-cats, weasels, rats, and certain birds, especially the night-birds, prey upon the cockchafer and its larvæ. Ravens and magpies, which are seen going from clod to clod, make savage but insufficient war against them. In fact, all these animals together do not destroy the hundredth part of the cockchafers which are born every year.
As an example which will show the extent of the evil, a field of 29 acres was ploughed up into 72 furrows. At the first ploughing were gathered 300 larvæ per furrow; at the second, 250; at the third, 30 more; which amounted to 600 per furrow, and to 43,200 in all. Man, who is the victim of these ravages, has been necessarily obliged to think of a means of destroying this enemy. Manyinfalliblemeans have been proposed, which have, however, given no result. Prizes have been offered, but the evil has not diminished. Here are a few of the processes recommended.
Immediately after the ploughing, you must turn into the field infested by the larvæ a flock of turkeys, to whom it will be a great treat to devour them, or else you must sow in the field rape-seed, very thickly, which you must then bury by a very deep ploughing, when it is as high as your hand. Colewort, it is said, kills the larvæ, while it at the same time manures the soil. Or again, you must plough up the land on the approach of hard frosts, to expose the worms to the cold. Lastly, you can water the field with oil of coal, or sprinkle it with ashes of boxwood. All these are expensive. The simplest means are here the best. It is better to depend upon labour than destructive substances, whose employment always presents inconveniences. Considering the difficulties which oppose themselves to us in our search after larvæ, we had better collect them in their adult state by violently shaking the branches of the trees on which they doze during the day, and then kill them in some way or other, thus destroying from twenty to forty eggs with each female. A general cockchafer hunt, rendered obligatory by a law, and encouraged by prizes, would be the only efficacious means of opposing a pest which costs agriculture many millions. This means would also be less costly than the turning up of the land concealing the larvæ, when it is remembered that they prefer land in full bearing.
In 1835 the General Council of La Sarthe voted a sum of 20,000 francs for a cockchafer hunt. Nearly 600,000 litres were delivered in, thanks to a prize of three centimes per litre. As a litre contains about 500 cockchafers, there were thus destroyed about 300,000,000 of them. It is true that M. Romieu, thenPrefect of La Sarthe, who was the principal promoter of this excellent measure, became food for the wit of the newspapers, and was represented dressed like a cockchafer in theCharivari. Derision and ridicule are too often the reward of useful ideas. In Switzerland were taken, in 1807, more than 150,000,000 of these insects. But these isolated measures were useless in producing a durable result.
It has been tried to make use of cockchafers in industrial arts. According to M. Farkas, they have succeeded, in Hungary, by boiling them in water, in extracting from them an oil, which is used to grease the wheels of carriages; and, according to M. Mulsant, the blackish liquid which is contained in the œsophagus may be used for painting. But the produce arising from these industrial occupations is not considerable enough to ensure them a certain extension, which is to be regretted, for agriculture would thus be rid of one of its most formidable scourges. Poultry are sometimes fed on these insects; pigs are also very fond of them.
TheMelolontha Hippocastanidiffers from the common species in having black legs. TheMelolontha fullo, twice as large as the common species, is variegated with tawny and white. It is met with on the sea-coasts, and on the downs of the north and south of France, as its larvæ feed on the roots of maritime plants.
Among the genera very near to the cockchafer we will mention the littleRhizotrogus, light-coloured and hairy, which flies in the evening in the meadows, and theEuchloras, orAnomalas, of splendid metallic colours. TheAnomala vitisis an insect of about half an inch long, of a beautiful green, bordered by yellow, with the elytra deeply furrowed. It sometimes causes extensive ravages in the vineyards.
After theCetoniadæand the Cockchafers, we come to theScarabæidæ, properly so called. TheOryctes nasicornis(Fig. 435) is very common all over Europe. It is about an inch long, of a chestnut-brown, and perfectly smooth. The male has on the head a horn, which is wanting in the female (Figs.436,437). Its larva, which is a great whitish worm, larger than that of the cockchafer, lives in rotten wood and in the tan which is employed in hot-houses and in garden-frames. They were to be found by hundreds in the old hot-houses of the Jardin des Plantes at Paris. The market-gardeners, who employ the tannin of the oak bark, have rendered this Coleopteron very common in the environs of that capital.Fig. 438represents an exotic species, theXylotrupes dichotomus.
Among the trueScarabæiwe meet with many species of giganticsize, especially in America.Dynastes Hercules, a great insect of a fine ebony black, with its elytra of an olive grey, is not rare in the Antilles. Its thorax is prolonged into a horn as long as its body, and bent round at the extremity; its head has also a long horn standing erect. The females want these appendages.Fig. 439represents theGolofa clavigerof Guyana.
TheGeotrupesare insects almost as common as the chafers. As their name reminds us, they make holes in the ground, which they scoop out, particularly in meadows, under cow-dung which has growndry on the surface. It is under the excrements of ruminating animals and horses that they must be looked for. They fly especially at night, and may be seen buzzing about on fine summer evenings in the vicinity of dung heaps.
Fig. 438.—Xylotrupes dichotomus.
TheGeotrupes stercorarius, the Shard-born Beetle, Clock, or Dumbledor, is of a brilliant bluish black, and attains to a length of about two-thirds of an inch. We may consider this Coleopteron as a useful auxiliary of man in ridding the soil of excrementitious matter. The genusTrox, which belongs to the same group, generally inhabits sandy countries, and has its body nearly always covered with earth or dust; it lives on vegetable substances, or on animal matter in a state of decomposition. The habits of the genusCoprisresemble those ofGeotrupes; they live in excrement. The form of their clypeus, broad, rounded, without teeth, and advancing over the mouth, suffices to distinguish the kindred species. In the environs of Paris and in England theCopris lunarisis found. The larvæ of these insects form a cocoon composed of earth and dung, before transforming themselves into pupæ; this cocoon is more or less round, and acquires a great hardness.
Fig. 439.—Golofa claviger.
The species of the genusAteuchuscollect portions of excrement, which they make up into balls, and roll till they are as perfectly rounded as pills, and in which they lay their eggs. This habit has gained for these insects the name of pill-makers. Their hind legs seem to be particularly adapted for this operation, for they are very long and somewhat distant from the other legs, which gives to theAteuchia strange appearance, and makes it hard work for them to walk. They walk backwards and often fall head over heels. They are generally seen on declivities exposed to the greatest heat of the sun, assembled together to the number of four or five, occupied in rolling the same ball; so that it is impossible to know which is the real proprietor of this rolling object. They seem not to know themselves; for they roll indifferently the first ball which they meet with, or near which they are placed.
Fig. 440.—Scarabæus (Golofa) Porteri.Fig. 440.—Scarabæus (Golofa) Porteri.
Fig. 441.—Scarabæus enema, or Enema infundibulum.Fig. 441.—Scarabæus enema, or Enema infundibulum.
TheAteuchiare large flat insects, with a broad-toothed clypeus; they all belong to the Ancient Continent. The type of the genus is theAteuchus sacer(Fig. 442), the Sacred Scarabæus of the Egyptians. This insect is black, and attains to a length of a little less than an inch. It is to be found commonly enough in the south of France, in the whole of southern Europe, Barbary, and Egypt. The paintings and amulets of the ancient Egyptians very often represent it, and sometimes give it a gigantic size. It is, doubtless, then, this species which was an object of veneration with the Egyptians.
There exists another species, which is always represented as of a magnificent golden green, and to which Herodotus also attributes this colour. As it was not to be found in Egypt, it was thought for a long while that the Egyptians had painted the black species of a more splendid colour in order to pay it homage. But in 1819 M. Caillaud actually found at Meroe, on the banks of the White Nile, theAteuchus Ægyptiorum, which resembles theAteuchus sacermuch in colour, but has a golden tint. Since then it has also been brought from Sennaar. The two species were both probably sacred. Hor-Apollon, the learned commentator on Egyptian hieroglyphics, thinksthat this people, in adopting the scarabæus as a religious symbol, wished to represent at once,a unique birth—a father—the world—a man. Theunique birthmeans that the scarabæus has no mother. A male wishing to procreate, said the Egyptians, takes the dung of an ox, works it up into a ball, and gives it the shape of the world, rolls it with its hind legs from east to west, and places it in the ground, where it remains twenty-eight days; the twenty-ninth day it throws its ball, now open, into the water, and there comes forth a male scarabæus. This explanation shows also why the scarabæus was employed to represent at the same time afather,a man, andthe world. There were, however, according to the same author, three sorts ofScarabæi: one was in the shape of a cat, and threw out brightly shining rays (probably the Golden Scarabæus,Ateuchus Ægyptiorum); the two others had horns; their description seems to refer to aCoprisand aGeotrupes.
As other remarkable species ofScarabæiwe represent theScarabæus enema(Fig. 441), with strong horns, theMegacerus chorinæus(Fig. 443), theMegalosoma anubis(Figs.444and445), and theDynastes Hercules(Fig. 446).
The last family of theScarabæidæcontains theLucanidæ, or Stag Beetles. These Coleoptera are of great size, and their head is armed with enormous robust mandibles, which give them a ferocious air, which their inoffensive habits do not in any way justify. They live in half-rotten trees, the destruction of which they accelerate. Their mandibles, of such prodigious size only in the male, are of more inconvenience to them than they are of use, as they impede their flight. Their strength enables them to raise considerable weights, but they make no other use of them than to show their strength, which is enormous. They do not attack other insects, and live only on vegetable juices.
The common Stag Beetle (Figs. 447[121]and 448) attains to a length of two inches, or more, including its mandibles, and is of a dark brown chestnut colour. They are met with during the months of May, June, and July, in large forests, climbing along trees and hooking themselves on to the trunks by their mandibles. Charles De Geer says that the Stag Beetle imbibes the honeyed liquid which is found on oak trees, a tree it particularly seeks after, which has caused it tobe called in SwedishEk-Oxe(Oak ox). It is supposed that it eats the leaves also. It sometimes attacks insects. Westwood says that it has been seen to descend from a tree carrying a caterpillar in its mandibles. Swammerdam had one which followed him like a dog when he offered it honey. They only fly in the evening, holding themselves nearly straight, so as not to see-saw. Their larvæ—which are whitish, with russety heads, live in the interior of trees, their existence in that state lasting nearly four years. Many naturalists think that the larva of theLucanuswas theCossusof the Romans, which figured on the tables of the rich patricians, and particularly of Lucullus.