Fig. 517.—Scarites lævigatus.Fig. 517.—Scarites lævigatus.Fig. 518.—Harpalus æneus.Fig. 518.—Harpalus æneus.Fig. 519.—Larva of Galerita Lecontei.Fig. 520. Galerita Lecontei.Fig. 521.—Mormolyce phyllodes.Fig. 522.—Larva and pupa of Mormolyce phyllodes.Fig. 523.—Tiger BeetleFig. 522.—Larva and pupa of Mormolyce phyllodes.Fig. 523.—Tiger Beetle (Cicindela campestris).TheCicindela campestris(Fig. 523), or Tiger Beetle, is of a beautiful green, spotted with white; the abdomen is of a bronze red. In this country it is the commonest of the genus. TheCicindela hybrida, of a dull green, relieved by light bands, inhabits sandy woods. TheCicindela maritimadiffers from the preceding. TheCicindela sylvatica, which flies very well, is not easy to catch, and is to be often met with in the warm glades of the forest of Fontainebleau and at Montmorency; it is not unfrequent here. Its colour is brown, spotted with white; it diffuses a strong smell of the rose, to which succeeds, on being seized, the acrid odour of the secretion which it disgorges. We here represent theCicindela Dumoulinii(Fig. 524), theCicindela rugosa(Fig. 525), theCicindela scalaris(Fig. 526), theCicindela heros(Fig. 527), theCicindela quadrilineata(Fig. 528), and theCicindela capensis(Fig. 529).Fig. 524.—Cicindela Dumoulinii.Fig. 525.—Cicindela rugosa.Fig. 526.—Cicindela scalaris.The ferocity of these insects is remarkable. They quickly tear off the wings and legs of their victim, and suck out the contents of its abdomen. Often, when they are disturbed in this agreeable occupation, not wishing to leave it, they fly away with their prey; their flight, however, is not sufficiently powerful to allow of their carrying to any great distance such a heavy burden. When aCicindelais seized between the fingers, it moves about its mandibles and endeavours to pinch, but its bite is inoffensive and not very painful. They are prodigiously active in running. Armed with jaws which are powerful enough to overcome their victims and to seize them at once, they can dispense with stratagem.Fig. 527.—Cicindela heros.Fig. 528.—Cicindela quadrilineata.Fig. 529.—Cicindela capensis.Fig. 530.—Larva of Cicindela campestris.Fig. 531.—Ambush of larva of Cicindela campestris.Their larvæ (Fig. 530) are soft, and have short legs. To satisfy their voracity they are obliged to lie in ambush in holes. They are two-thirds of an inch long; their head is horny and in the form of atrapezium. The first segment is also horny, and of a metallic green. The eighth has a pair of tubercles with hooks, of which the larva makes use in ascending and descending its vertical hole, like a sweep in a chimney. This hole (Fig. 531) is a foot or more deep. To dig it, the larva employs its mandibles and its legs in the following manner: it twists itself round, loads with earth the flat surface which covers itshead, climbs along the chimney by twisting itself into the form of the letter Z, and thus transports its load, as a bricklayer's labourer carries a hod of mortar up a ladder. Arrived at the mouth of the hole, it throws to a distance the rubbish with which its head is loaded; or, if too heavy, it simply deposits it, pushing it away as far as possible. It is difficult to watch their proceedings, for they are very mistrustful, and retire immediately into their hole when alarmed. They remain in ambush at the entrances of these subterranean passages, which they hermetically seal with their head and thorax. It is a species of pitfall which sets itself in motion the moment anything endeavours to pass it. The unfortunate who ventures is precipitated into the well, and theCicindelaforthwith devours it. These habits remind one of those of the ant-lion. When the time arrives for the metamorphosis, the larva of theCicindelaenlarges the bottom of its hole, and stops up the entrance with earth before changing. The pupa (Figs. 532, 533) is of a pale glossy yellow, covered with small spines. The metamorphosis takes place between August and October; the perfect insect emerges in spring.Fig. 532, 533.—Pupa of a Cicindela (Upper- and Under-side).Upper-side.Under-side.Fig. 532, 533.—Pupa of a CicindelaFig. 534.—Tetracha Klugii.Fig. 535.—Tetracha oxychiloides.Nearly akin to theCicindelasare theTetrachas(Figs.534,535,536), from Africa and tropical America; theManticoras(Fig. 537), which are distinguished by their robust and thick-set appearance; thePogonostomas(Fig. 538), which live in Madagascar; theCtenostomas, peculiar to America (Fig. 539), remarkable for the length of their pendent and bristly palpi; theOmus, of California; theTherates(Fig. 540), insects of the East Indian Islands, &c.Fig. 536.—Tetracha bifasciata.The tribe ofTenebrionidæ, called formerlyMelasomas, because they are nearly all black, resembles in some points theCarabici. They seek after dark places, and avoid the light, and are found on the ground under stones; their movements are slow, and they walk with difficulty. The best-known insect of this group is theBlaps, of repulsive smell, inhabiting dark damp places, such as cellars, and only coming out of its retreat during the night. The elytra are joinedtogether, and they have no wings. The vulgar regard them as an omen of ill-luck.Fig. 541represents theBlaps obtusa. According to the report of a traveller, the women in Egypt eat theBlaps sulcatacooked with butter, to make them fat. They are employed also against the ear-ache, the bite of scorpions, &c.Another genus of the same family is theTenebrio(Fig. 542), of a blackish-brown, with the elytra striated, and of half an inch in length. The larvæ, the well-known meal-worms, live in flour; they are cylindrical, and of a light tawny colour (Fig. 542). The insect which is considered as a type of the tribe of thePimelidesis thePimelia bipunctata, which is common in the south of France.Fig. 537—Manticora tuberculata.Fig. 538.—Pogonostoma gracilis.We come now to the tribe of blistering beetles, of which the best known is the Cantharides (CantharisorLytta). These insects are generally of soft consistency, and their elytra very flexible. A fewremain constantly on trees. All are very brisk and active. When swallowed they are a dangerous poison, but are used in medicine for making blisters.Fig. 539.—Ctenostoma rugosa.Fig. 540.—Therates labiata.Fig. 542.—Tenebrio molitor (larva and imago).Fig. 541.—Blaps obtusa.Fig. 542.—Tenebrio molitor(larva and imago).The Cantharides of commerce (Cantharis [Lytta] vesicatoria) are of a beautiful green, attain to a size of four-fifths of an inch, and are found on ash-trees, lilacs, and other shrubs. Commerce for a long time brought them from Spain, and some still come from that country; hence the common name ofSpanish fly. As they live in great numbers together, collecting them is easier and less expensivethan would be that of other species of the same family which are not gregarious, but which have the same medicinal properties. The presence of the Cantharides is manifested by the strong penetrating odour which they diffuse to some distance. When, by aid of this smell, they are discovered, generally settled on an ash, they are collected in the following manner:—Very early in the morning a cloth of light tissue is stretched out at the foot of the tree, and the branches are shaken, which causes the insects to fall (Plate XII.). These, numbed by the cold of the night, do not try to escape. When there is a sufficient quantity, the four corners are drawn up and the whole plunged into a tub of vinegar diluted with water. This immersion causes the death of the insects. They then carry them to a loft, or under a very airy shed. To dry them they spread them out on hurdles covered with linen or paper, and from time to time, to facilitate the operation, they are moved about, either with a stick or with the hand, which is more convenient; but it is then necessary to take the precaution of putting on gloves, for, if touched with the naked hand, they would cause more or less serious blisters. The same precaution must be observed in gathering them.When the Cantharides are quite dry, they put them into wooden boxes or vessels of glass or earthenware hermetically sealed, and preserve them in a place protected from damp. With these precautions,they may be kept for a long while without losing any of their caustic properties. Dumeril made blisters of Cantharides which had been twenty-four years in store, and which had lost none of their energy. When dry, they are so light that a kilogramme contains nearly 13,000 insects. Aretius, a physician who flourished at Rome in the first century of our era, seems to have been the first to employ Cantharides, reduced to powder, as a means of vesication. Hippocrates administered them internally in cases of dropsy, apoplexy, and jaundice. But it is pretty nearly established that the Cantharides of the ancients were not the same species used at the present day; they were, probably, a kindred species, theMylabris chicorii. A blistering principle has been extracted from these insects, calledCantharadine. This organic product presents itself under the form of little shining flakes, without colour, soluble in ether or oil. One atom of this matter applied to the skin, and particularly to the lower lip, makes the epidermis rise instantaneously, and produces a small blister filled with a watery liquid. In spite of the corrosive principle which theCanthariscontains, it is attacked, like other dried insects, by theDermestesand theAnthrenus, which feast on them without suffering the smallest inconvenience.XII.—Gathering Cantharides.TheStylopidæ, for which Kirby,[122]in 1811, instituted a distinct Order, which he calledStrepsiptera, in allusion to the contortion of the elytra, and to which Latreille[123]subsequently applied the name ofRhipiptera, are, perhaps, the most anomalous of all insects. Great diversity of opinion has existed respecting their affinities; but modern systematists, with but few exceptions, concur in referring them to the OrderColeoptera, and locating them in proximity toMeloë. In the larva state, all the known species of the family inhabit the bodies of hymenopterous insects of the generaAndrena,Polistes, &c., in this particular resembling the dipterous genusConops, which inhabits the body of humble bees,[124]and apparently in no way inconveniencing their victims; a fact which has been accounted for on the supposition that their existence in the larva state is but short, and that their attacks being directed against the abdomen, and not the thorax, the seat of life in insects, their presence does not affect the activity of the victim. The larva has a soft fusiform body, surmounted by a somewhat globose head. While feeding, the head is towards the base of the abdomen; but on changing to a pupa, this position is reversed, and the head—at first of light brown, but which after a short time becomes black—thrust out between the plates of the abdomen.The imagos, which are of small size, namely, about the eighth of an inch long, are found during May and June. They have four wings, but the anterior pair, of hard texture, somewhat resembling elytra, but hardly answering to them in structure, are very poorly developed, and curled round the front pair of legs, hence the name bestowed, by Kirby, from [Greek: strepssis], a twisting, and [Greek: pteron], a wing; the posterior wings are fully developed, and fold up like a fan, whence the Order received the name ofRhipipterafrom Latreille. The eyes, the facettes of which are few in number, are placed on a footstalk, whence the name of the genusStylops. The parts of the mouth connect the Strepsiptera with the mandibulated insects, although by some supposed to bear analogy by their functions to those parts in the Diptera. The male only is winged; the female is very like an apodal larva, the larva being an active hexapod.The familyStylopidæis divided into four genera, of which two only,XenosandStylops, were described by Kirby in the essay referred to above. First,Xenos, from [Greek: xenos], a guest, the most prolific in species, of whichXenos Rossii, sometimes calledvesparum, may be taken asthe type. Secondly,Elenchus, of whichElenchus Walkeriis the type. Thirdly,Stylops(Fig. 543), parasitical on various species ofAndrenæ, of whichStylops Melittæ, having a fleshy abdomen and the wings longer than the body, may be considered typical: and lastly,Halictophagus, of which only one species, infestingHalictus æratus[125]namedHalictophagus Curtisii, is known to exist, and which makes its appearance in the month of August.Fig. 543.—Stylops (magnified).Fig. 543.—Stylops (magnified).These singular insects are found in various parts of the world—Europe, Australia, and America. They were discovered by Professor Peck almost simultaneously with Mr. Kirby's discovery in this country, and to whom he sent specimens of a species which has received the name ofXenos Peckiilately, in New Zealand and elsewhere.Siebold, in 1843, having obtained some eggs, was able to observe the larvæ, and he soon discovered that the females of Stylops, one of the Strepsiptera, were blind, had no legs, and always retained the appearance of larvæ, and that they never quitted the bodies of those insects, in which they pass a parasitic existence. George Newport paid great attention to the history of these curious insects, and when he wrote his article, "Insecta," in the "Cyclopædia of Anatomy and Physiology," four distinct genera of these minute parasites had already been discovered. One of the largest species (Stylops Spencii) is scarcely more than two lines in length, while the smallest species yet known is not more than two-thirds of a line, or scarcely a line in breadth with its wings expanded. They undergo metamorphosis; and the males, when they have become perfect insects, fly and roam about, but the females are condemned to a perfectly quiet life. The head and the thoracic segments of the bodies of these last are united completely, but the abdomen, which is very large, always remains soft, so that the whole of the body only appears to be formed of two portions. They are ovo-viviparous insects, and the young larvæ escape as such from the body of the mother. They are active creatures, and, being furnished with long legs, crawl over the hairs and skin of the hymenopterous insect they are parasitic upon. They behave like the larvæ of Meloë and Sitaris, whose peculiar methods of life have been noticed in our description of the Coleoptera. Clinging on to a wasp or a bee, they are carried off, and finallyarrive in the nest or hive, as the case may be, and there they attack the larvæ. When once fixed upon the hymenopterous larvæ, they undergo a change of skin, and their shape then becomes totally different, and their legs are atrophied. But these parasites being exceedingly small, do not kill the larvæ; they suck their juices, after the manner of the Ichneumons, and do not interfere with the metamorphoses of the insects upon which they are parasitic. On the right hand, in the accompanying engraving (Fig. 544), there is a larvamuch magnified, lately born, and climbing upon the hair of one of the Hymenoptera, and on the left hand there is a perfect female insect, very much magnified, with ovo-viviparous larvæ within its abdomen, and between the two figures there is a representation of a larva of the natural size. It is evident, however, that ova may be expelled from the mother before they are hatched.Fig. 544.—Female and Larva of Stylops.Packard describes the curious history of the female Stylops, which he found parasitic on one of the bees. He caught the bee, and on examining it he noticed a pale reddish-brown triangular mark on the abdomen, and this was the flattened head and thorax of a female Stylops. The creature is included in the body of the bee, and is nourished by its juices. The head and thorax of the parasite were noticed to be soldered into a single flattened mass, the baggy hind body being greatly enlarged, like that of the female white ant. On carefully drawing out the whole body from the bee the mass was found to be very extensible, soft, and baggy, and on examining it under a high power of the microscope, multitudes of very minute larvæ were observed, and they began to issue out from the body of the parent all alive, and not as eggs. The male of thisStylops childreniis totally unlike its partner, having large hind wings, and being able to fly, as has already been noticed. It appears, then, that the larvæ are hatched or crawl out of the body of the mother on to the body of the bee, and are then transported to its nest; then they enter the body of the bee larva, and live upon its fatty matter. The male Stylops is turned into a pupa within the bee, and so is the female; but after the second metamorphosis the male flies off, leaving his wingless partner imprisoned for life, and she usually dies immediately after giving birth to her myriad offspring (Packard). The female respires by peculiarly arranged tracheæ, and absorbs nourishment through her skin as well as by means of an alimentary canal, which ends in a blind sac. All the beauties of the female, so far as they are visible to the male, consist in the tiny patch which appears just without the body of the unfortunate bee, and the ova collect in a space which opens between the united head and body and the abdomen.The genusMylabriscorresponds most in structure, in appearance, and in properties, toCantharis, whose place they take in the East, in China, and in the south of Europe. They are found in clusters on the flowers of chicory, thistles, &c. TheMylabris chicorii, common enough in France, especially in the south, is of small size, whilst the other species are rather large. It is black, hairy, with a large yellowish spot at the base of each elytron, and two transverse bands of the same colour.Another genus of this family isMeloë, with very short elytra, and without wings. They walk slowly and with difficulty on low plants, the female dragging along an enormous abdomen filled with eggs. They are generally observed in spring. In Germany they give them the name ofMaiwurm(Mayworm). Their succulence would expose them, without doubt, to the voracity of birds and of insect-eating Mammifers if they had not the power of exuding at will, in the moment of danger, from all their articulations, an unctuous humour of a reddish-yellow colour, the odour and probably also the caustic properties of which repel the aggressor. The females lay their eggs underground, and out of these come forth larvæ of a strange shape. Swallowed by cattle, they cause them to swell and die. It is for this reason that Latreille has given it as his opinion that these insects are theBuprestisof the ancients, of which the law of Cornelius speaks, "Lex Cornelia de sicariis et veneficis." But the name ofBuprestiswas applied by Linnæus to a genus of which we shall treat farther on, and it has been generally adopted by naturalists.Fig. 546.—First larva of Sitaris humeralis (magnified).Fig. 545.—Sitaris humeralis.Fig. 546.—First larva of Sitaris humeralis(magnified).The commonest among theMeloësis theMeloë proscarabæus, which is to be found in abundance, in the month of April, in the meadows near the bridge of Ivry in the environs of Paris. The metamorphoses of the insects of this family had remained for a longtime surrounded with an impenetrable veil of mystery, but the researches of Newport in England, and of M. Fabre (of Avignon) in France, has made known in our days, phases, extremely curious, under which are accomplished the metamorphoses of theMeloë cicatricosus, and of theSitaris humeralis, a species which belongs to the same family.[126]These observations, of which we are about to give a rapid summary, will probably help towards unravelling the first states ofCantharis.Fig. 547.—Pseudo-nymph of Sitaris humeralis.Fig. 547.—Pseudo-nymphof Sitaris humeralis.Fig. 548.—Third larva of Sitarishumeralis.Fig. 549.—Pupa of Sitarishumeralis.TheSitaris humeralis(Fig. 545) takes no nourishment when arrived at the perfect state. When the female has been impregnated, she lays at the entrance of the nest of a solitary bee from 2,000 to 3,000 small whitish eggs, stuck together in shapeless masses. A month afterwards there come out of these eggs very small larvæ, of a shiny dark green, hard-skinned, armed with strong jaws, and long legs and antennæ (Fig. 546). These are the first larvæ. They remain motionless, and without taking food, till the following spring. At this period are hatched the male bees, which precede the appearance of the females by a month. As the bees come out of their nests, these larvæ hook themselves on to their hairs, and pass them to the females, at the coupling period. When the male bees have built the cells, and furnished them with honey, the female, as we know, deposits in each an egg. Immediately the larvæ of theSitarislet themselves fall on these eggs, open them, and suck their contents. Then they change their skin, and the second larva appears. This one gets into the honey, on which it feeds for six weeks. It is blind, whereas the first larva was provided with four eyes, no doubt to enable it to see the bees which were to serve as its conductors, in likemanner as the companions of Ulysses watched the sheep of Polyphemus, so as to escape out of the cave in which they were retained as prisoners. A few days later, and this second larva contracts, and detaches from its body a transparent skin, which discloses a mass, at first soft, which very soon hardens, and becomes of a bright tawny colour; it is called thepseudo-nymph(Fig. 547). It goes through the winter in this state. In the spring comes forth a third larva (Fig. 548), resembling the second. This one does not eat, and moults after a time. It very soon changes into an ordinary pupa (Fig. 549), of a yellowish-white, from which comes forth the adultSitaris, which lives only a few days, to ensure the propagation of its species, as is observed in the case of theEphemeræ. The larvæ of theSitarishad for a long time been remarked clinging on to the hairs of theAnthophoras, but they were always taken forAcari, and they had been described as such.Fig. 550.—Lampyris noctiluca (male and female).Fig. 550.—Lampyris noctiluca (male and female).TheLampyridæhave the elytra weak and soft, like the insects of the preceding tribe. In their perfect state they frequent flowers. The larvæ are carnivorous, attacking other insects or worms. It is to this group that theLampyris noctiluca, or glow-worm, which one sees shining during summer nights on grass and bushes, belongs. It has the power of making this natural torch shine or disappear at will.The luminous properties with which these insects are endowed have for their object to reveal their presence to the opposite sex, for the females alone possess these properties. In the same way as sounds or odours exhaling from some insects attract the one towards the other sex, so with theLampyrisa phosphorescent light shows the females to the males. The seat of the phosphorescent substance varies according to the species. It exists generally under the three last rings of the abdomen, and the light is produced by the slow combustion of a peculiar secretion. It has been stated that it is evolved quickly when the animal contracts its muscles, eitherspontaneously or under the influence of artificial excitement. Some chemical experiments have been made to ascertain the nature or the composition of the humour which produces this strange effect; but up to this moment, they have only enabled us to discover that the luminous action is more powerful in oxygen, and ceases in gases incapable of supporting combustion. In the most common species, theLampyris noctiluca, or glow-worm, the phosphorescence is of a greenish tint: it assumes at certain moments the brightness of white-hot coal.The females have no wings, while the males have them, and possess very well-developed elytra. The females resemble the larvæ much, only they have the head more conspicuous, and the thorax buckler-shaped, like the male. The larvæ feed on small molluscs, hiding in the snails' shells, after having devoured the inhabitant. They also possess the phosphorescent property in a less degree than the adult females. The female pupa resembles the larva; the pupa of the male, on the contrary, has the wings folded back under a thin skin. The perfect insect appears towards the autumn.The Glow-worm (Lampyris noctiluca,Fig. 550) is of a brownish yellow. It is common in England. In a kindred species, theLuciola Italica, the two sexes are winged, of a tawny-brown, and equally phosphorescent. They are met with in great numbers in Italy, and the lawns are covered with them. Other insects of this family are without the faculty of emitting light; as, for example, the genusLycus, of brilliant colours, which are met with in Africa and India. One of the finest is theLycus latissimus.Drilusis another genus, comprising insects of very singular habits. The type is theDrilus flavescens. The male—a quarter of an inch long, black and hairy, with elytra of a testaceous yellow, and with pectinated antennæ—for a long time was alone known. The female—from ten to fifteen times as large, without wings and elytra, of a yellowish brown—was not discovered till much later, having apparently nothing in common with the male in shape or colour. The metamorphoses of these curious insects are now perfectly understood. Mielzinsky, a Polish naturalist established at Geneva, found theDrilusin the larva state in the shell of theHelix nemoralis. These larvæ devour the snail whose dwelling they occupy, as do the larvæ of theLampyris. Mielzinsky saw them emerge, but obtained only females, which differed scarcely at all from the larvæ from which they proceeded. He made a separate genus of them, under the denomination ofCochleoctonus, and called the speciesVorax. Later,Desmarest resumed these observations. He provided himself, at the Veterinary College of Alfort, with a number of shells of theHelixfilled with the same larvæ. He saw come out of them, not onlyCochleoctoni, but alsoDrili, and he watched their coupling. It was then proved, by this unanswerable argument, that these two insects, so unlike each other, belong to the same species.Fig. 551.—Jumping organ of the Elater.Fig. 552.—Jumping organ of the Elater, seen sideways.Fig. 552.—Jumping organ of the Elater,seen sideways.Fig. 553.—Larva of the Elater.Fig. 551.—Jumping organof the Elater.Fig. 553.—Larva of the Elater.The larva of theDrilus flavescensfixes itself upon the shell of the snail by a sort of sucker, like a leech. Little by little it slips in between the mollusc and its house, and devours it entirely. To change into a pupa, it shuts up the entrance to the shell with its old skin; and when arrived at the perfect state, quits the shell which served it as a temporary dwelling. The females of theDrilus flavescenstake refuge under stones and dry leaves, or crawl slowly along the ground; whilst the males, which fly with great ease, are on the plants and brushwood. These insects are not rare in the environs of Paris. M. H. Lucas has observed, in Algeria, near to Oran, another curious species, theDrilus Mauritanicus. The larva of this insect lives at the expense of the animal of theCyclostoma Volzianum, which closes the entrance to its shell with a covering of some calcareous substance. It fixes itself on the edge of the shell, with the aid of its sucker, and directs its strong mandibles to the side on which the snail is obliged to raise the covering, either to breathe the air or to walk. In this position it has the patience to wait formany days at the door. The snail puts off for as long a time as he is able the fatal moment. But when, overcome by hunger or nearly stifled in his prison, he decides at last to open the door, theDrilusprofits immediately by this opportunity, and cuts the muscle which keeps back the foot of the snail. The breach being made, nothing more opposes itself to the entrance of the enemy. He slips in, and sets to work to eat at his leisure the unfortunate inoffensive mollusc, which affords him board and lodging. ThePtilodadylides, theEucinetides, and theCebrionidesbelong to the same family. The first is exotic.TheElateridæare rather large insects, often of hard texture, having the prosternum prolonged into a point (Figs.551and552), and the antennæ indented saw-wise. They have the power of jumping when placed on their backs, and of alighting again on their legs. Hence their name ofElater(derived from the same root as the wordelastic). They produce, in leaping, one sharp rap, and often knock many raps when they are prevented from projecting themselves. This is the mechanism which permits the skip-jack to execute these movements. It bends itself upwards by resting on the ground by its head and the extremity of the abdomen, and then it unbends itself suddenly, like a spring. The point at the end of the thorax penetrates into a hollow of the next ring; the back then strikes with force against the plane on which it rests, and the animal is projected into the air. It repeats this manœuvre till it finds itself on its belly, for its legs are too short to allow of its turning over. Its structure supplies it with the means and the strength of rebounding as many times as it falls on its back, and it can thus raise itself more than twelve times the length of its body.The larvæ of the genusElateridæ(Fig. 553) are cylindrical, with a scaly skin and very short legs. They live in rotten wood or in the roots of plants. According to M. Goureau, they pass five years in this state.The larvæ of the genusAgriotesoccasion considerable damage to wheat-fields. They have much resemblance to the meal-worm, or larva of theTenebrio. TheTetralobidesare the largest of theElateridæ, attaining to a length of two inches; and are inhabitants of Africa and Australia.In America are found phosphorescentElateridæ. These are thePyrophori, which the Spaniards of South America call by the name ofCucuyos. They have, at the base of their thorax, two small, smooth, and brilliant spots, which sparkle during the night; the rings of the abdomen also emit a light. They give light sufficient toenable one to read at a little distance from them. ThePyrophorus noctilucus(Fig. 554) is very common in Havannah, in Brazil, in Guyana, in Mexico, &c., and may be seen at night in great numbers, amongst the foliage of trees. At the time of the Spanish conquest, a battalion, just disembarked, did not dare to engage with the natives, because it took the Cucuyos which were shining on the neighbouring trees for the matches of the arquebuses ready to fire. "In these countries," says M. Michelet, "one travels much by night, to escape the heat. But one would not dare to plunge into the peopled shades of the deep forests if these insects did not reassure the traveller. He sees them shining afar off, dancing, twisting about; he sees them near at hand on the bushes by his side; he takes them with him; he fixes them on his boots, so that they may show him his road and put to flight the serpents; but when the sun rises, gratefully and carefully he places them on a shrub, and restores them to their amorous occupations. It is a beautiful Indian proverb that says, 'Carry away the fire-fly, but restore it from whence thou tookest it'"[127]The Creole women make use of the Cucuyos to increase the splendour of their toilettes. Strange jewels! which must be fed, which must be bathed twice a day, and must be incessantly taken care of, to prevent them from dying. The Indians catch these insects by balancing hot coals in the air, at the end of a stick, to attract them, which proves that the light which these insects diffuse is to attract. Once in the hands of the women, the Cucuyos are shut up in little cages of very fine wire, and fed on fragments of sugar-cane. When the Mexican ladies wish to adorn themselves with these living diamonds, they place them in little bags of light tulle, which they arrange with taste on their skirts. There is another way of mounting the Cucuyos. They pass a pin, without hurting them, under the thorax, and stick this pin in their hair. The refinement of elegance consists in combining with the Cucuyos, humming-birds and real diamonds, which produce a dazzling head-dress. Sometimes, imprisoning these animated flames in gauze, the graceful Mexican women twist them into ardent necklaces, or else roll them round their waists, like a fiery girdle. They go to the ball under a diadem of living topazes, of animated emeralds, and this diadem blazes or pales according as the insect is fresh or fatigued. When they return home, after thesoirée, they make them take a bath, which refreshes them, and put them back again into the cage, which sheds during the whole night a soft light in the chamber. In 1766, a Cucuyo, brought alive fromAmerica to Paris, probably in some old piece of wood which happened to be on the vessel, caused great terror to the inhabitants of the Faubourg St. Antoine, when they saw it flying in the evening, glittering in the air. In 1864 a number of Cucuyos were brought from Mexico to Paris by M. Laurent, captain of the frigateLa Floride. An experiment, made in the laboratory of the École Normal, showed that the spectrum of their light is continuous, without any black rays; it differs, besides, from the spectrum of the solar light by a greater intensity of the yellow colour. The light is produced probably as it is in the case of theLampyris, by the slow combustion of a substance secreted by the animal. The Cucuyo can, nevertheless, at will, increase or diminish the splendour of this light by means of membranes which it superposes, like screens, in front of the phosphorescent bumps which it has on its thorax.Fig. 554.—The Cucuyo (Pyrophorus noctilucus).Fig. 555.—Buprestis (Cyria) imperialis.Fig. 554.The Cucuyo (Pyrophorus noctilucus).Fig. 555.Buprestis (Cyria) imperialis.In the Indies, and in China, the women use for dressing their hair with, or as ear-rings, another Coleopteron of the same tribe, which begins even to be employed for this purpose by the women of the south of France. It is aBuprestis, of splendid colours, and of metallic brightness. Linnæus, as we said above, gave to it, wrongly, the name ofBuprestis, which among the ancients served to designate a very different insect, theMeloë, of the family of theCantharidæ; but modern naturalists have allowed this illegitimate title.TheBuprestidæwalk heavily, but fly with the greatest ease during the heat of the sun, and settle on the trunks of trees exposed to itsrays. In Europe, and especially in the North, they are very rare, and of very small size. They must be looked for on birch-trees, whose white colour seems to attract them. In the hottest parts of the world they are very abundant, of large dimensions, and adorned with sparkling colours. They do not jump, and are not endowed with the phosphorescent property. Their larvæ have no legs, are elongate, whitish, of a fleshy consistency, with the first ring of their bodies very much broadened. They live in the trunks of trees, between the bark and the wood, hollowing out for themselves irregular galleries, and remaining sometimes in this state for ten years before metamorphosing. Laporte de Castelnau and Gory have described and made drawings of about 1,300 species ofBuprestidæ.Fig. 555represents theBuprestis imperialis. TheBuprestis albosparsa, the generaJulodis, theChrysochroas, and theTrachysbelong also to the great family ofBuprestidæ. TheCleridæare connected with the preceding. They have the thorax narrower than the elytra, and rather long; their integuments are less solid than those of theElateridæand theBuprestidæ. The latter are phytophagous, the former carnivorous. The principal type of this family is theClerus formicarius, russety, with the head and legs black, whose larva lives at the expense of the larvæ of the weevil. Another genus, theNecrobia, which lives on dried animal matter, has become celebrated, as it was the cause of the salvation of the greatest entomologist of France. The name ofNecrobia(from [Greek: nekros] and [Greek: biôs]) does not mean "which lives on dead bodies," but it means "life in death." Here is the story of which this name is destined to preserve the remembrance, and which Latreille himself has related in his "Histoire des Insectes." Before 1792, Latreille was known only from some memoirs which he had published on insects. He was then priest at Brives-la-Gaillarde, and was arrested with the curés of Limousin, who had not taken the oath. These unfortunates were then taken to Bordeaux in carts, to be transported to Guyana. Arrived at Bordeaux in the month of June, they were incarcerated in the prison of the Grand Séminaire till a ship should be ready to take them on board. In the meanwhile, the 9th Thermidor arrived, and caused the execution of the sentence which condemned the priests who had not taken the oath to transportation to be for a while suspended. However, the prisons emptied themselves but slowly, and those who had been condemned had none the less to go into exile, only their transportation had been put off till the spring."Latreille remained detained at the prison of the Grand Séminaire. In the same chamber which he occupied there was at thetime an old sick bishop, whose wounds a surgeon came each morning to dress. One day as the surgeon was dressing the bishop's wounds, an insect came out of a crack in the boards. Latreille seized it immediately, examined it, stuck it on a cork with a pin, and seemed enchanted at what he had found."Is it a rare insect, then?" said the surgeon."Yes," replied the ecclesiastic."In that case you should give it to me.""Why?""Because I have a friend who has a fine collection of insects, who would be pleased with it.""Very well, take him this insect; tell him how you came by it, and beg him to tell me its name."The surgeon went quickly to his friend's house. This friend was Bory de Saint Vincent, a naturalist who became celebrated afterwards, but who was very young at that time. He already occupied himself much with the natural sciences, and in particular with the classing of insects. The surgeon delivered to him the one found by the priest, but in spite of all his researches, he was unable to class it.Next day the surgeon having seen Latreille again in his prison, was obliged to confess to him that in his friend's opinion this Coleopteron had never been described. Latreille knew by this answer that Bory de Saint Vincent was an adept. As they gave the prisoner neither pen nor paper, he said to his messenger, "I see plainly that M. Bory de Saint Vincent must know my name. You tell him that I am the Abbé Latreille, and that I am going to die at Guyana, before having published my 'Examen des Genres de Fabricius.'"Bory, on receiving this piece of news, took active steps, and obtained leave for Latreille to come out of his prison, as a convalescent, his uncle Dayclas and his father being bail for him, and pledging themselves formally to deliver up the prisoner the moment they were summoned to do so by the authorities. The vessel which was to have conducted Latreille to exile, or rather to death, was getting ready whilst these steps were being taken, and while Bory and Dayclas were obtaining leave for him to come out of prison. This was quite providential, for it foundered in sight of Cordova, and the sailors alone were able to save themselves. A little time afterwards his friends managed to have his name scratched out from the list of exiles. It is thus that theNecrobia ruficolliswas the saving of Latreille.The tribe of weevils is even much more numerous than that of theElateridæand theBuprestidæ. One may know them by their head prolonged into a snout or trunk, by their rudimentary mouth, and by their elbowed antennæ. About twenty thousand species are said to exist. They feed on vegetables. Their larvæ are soft, whitish worms, without legs, with very small heads, and live in the interior of the stalks or seeds of plants, often occasioning enormous damage. They are one of the plagues of agriculture. Each of our dry vegetables, each variety of our cereals, has in this immense family its particular enemy.First are theBruchi. The Pea Weevil (Bruchus pisi,Fig. 556), which is brown with white spots, comes out of the pea at the end of the summer. The female lays her eggs on peas which are ripe, and still standing, in which the larva scoops out a habitation, and then makes its exit by a circular hole (Fig. 557). It remains at rest all the winter, and is not hatched till towards the following spring. The Bean Weevil (Bruchus rufimanus) marks each bean with many black spots. The vetch has also its specialBruchus. The Wheat Weevil (Calandra granaria), of a darkish brown, lays its eggs on the grains, of which the larvæ then eat the interior. A host of ways of getting rid of the weevil have been proposed. The best means is to store corn properly, and to keep the heap well aired. Let us mention further, the Clover Weevil, belonging to the genusApion, the Weevil of the Rape (Ceutorhynchus brassicæ), the Turnip Weevil, &c., &c.Fig. 556.—Pea Weevil(Bruchus pisi), magnified.Fig. 557.—Pea pierced by the larva.All vegetables, the vine, fruit trees, the ash, pines, &c., are eaten by some weevil or other. As an example we give a figure of the spottedPissodes pini, which, as the figure shows, takes the precaution of cutting half through the young stems and the stalks of the buds of the pine, "so as," says M. Maurice Girard,[128]"that the sap flowsonly with difficulty into the withered organ, and cannot suffocate the young larvæ."
Fig. 517.—Scarites lævigatus.Fig. 517.—Scarites lævigatus.
Fig. 521.—Mormolyce phyllodes.
TheCicindela campestris(Fig. 523), or Tiger Beetle, is of a beautiful green, spotted with white; the abdomen is of a bronze red. In this country it is the commonest of the genus. TheCicindela hybrida, of a dull green, relieved by light bands, inhabits sandy woods. TheCicindela maritimadiffers from the preceding. TheCicindela sylvatica, which flies very well, is not easy to catch, and is to be often met with in the warm glades of the forest of Fontainebleau and at Montmorency; it is not unfrequent here. Its colour is brown, spotted with white; it diffuses a strong smell of the rose, to which succeeds, on being seized, the acrid odour of the secretion which it disgorges. We here represent theCicindela Dumoulinii(Fig. 524), theCicindela rugosa(Fig. 525), theCicindela scalaris(Fig. 526), theCicindela heros(Fig. 527), theCicindela quadrilineata(Fig. 528), and theCicindela capensis(Fig. 529).
The ferocity of these insects is remarkable. They quickly tear off the wings and legs of their victim, and suck out the contents of its abdomen. Often, when they are disturbed in this agreeable occupation, not wishing to leave it, they fly away with their prey; their flight, however, is not sufficiently powerful to allow of their carrying to any great distance such a heavy burden. When aCicindelais seized between the fingers, it moves about its mandibles and endeavours to pinch, but its bite is inoffensive and not very painful. They are prodigiously active in running. Armed with jaws which are powerful enough to overcome their victims and to seize them at once, they can dispense with stratagem.
Their larvæ (Fig. 530) are soft, and have short legs. To satisfy their voracity they are obliged to lie in ambush in holes. They are two-thirds of an inch long; their head is horny and in the form of atrapezium. The first segment is also horny, and of a metallic green. The eighth has a pair of tubercles with hooks, of which the larva makes use in ascending and descending its vertical hole, like a sweep in a chimney. This hole (Fig. 531) is a foot or more deep. To dig it, the larva employs its mandibles and its legs in the following manner: it twists itself round, loads with earth the flat surface which covers itshead, climbs along the chimney by twisting itself into the form of the letter Z, and thus transports its load, as a bricklayer's labourer carries a hod of mortar up a ladder. Arrived at the mouth of the hole, it throws to a distance the rubbish with which its head is loaded; or, if too heavy, it simply deposits it, pushing it away as far as possible. It is difficult to watch their proceedings, for they are very mistrustful, and retire immediately into their hole when alarmed. They remain in ambush at the entrances of these subterranean passages, which they hermetically seal with their head and thorax. It is a species of pitfall which sets itself in motion the moment anything endeavours to pass it. The unfortunate who ventures is precipitated into the well, and theCicindelaforthwith devours it. These habits remind one of those of the ant-lion. When the time arrives for the metamorphosis, the larva of theCicindelaenlarges the bottom of its hole, and stops up the entrance with earth before changing. The pupa (Figs. 532, 533) is of a pale glossy yellow, covered with small spines. The metamorphosis takes place between August and October; the perfect insect emerges in spring.
Nearly akin to theCicindelasare theTetrachas(Figs.534,535,536), from Africa and tropical America; theManticoras(Fig. 537), which are distinguished by their robust and thick-set appearance; thePogonostomas(Fig. 538), which live in Madagascar; theCtenostomas, peculiar to America (Fig. 539), remarkable for the length of their pendent and bristly palpi; theOmus, of California; theTherates(Fig. 540), insects of the East Indian Islands, &c.
Fig. 536.—Tetracha bifasciata.
The tribe ofTenebrionidæ, called formerlyMelasomas, because they are nearly all black, resembles in some points theCarabici. They seek after dark places, and avoid the light, and are found on the ground under stones; their movements are slow, and they walk with difficulty. The best-known insect of this group is theBlaps, of repulsive smell, inhabiting dark damp places, such as cellars, and only coming out of its retreat during the night. The elytra are joinedtogether, and they have no wings. The vulgar regard them as an omen of ill-luck.Fig. 541represents theBlaps obtusa. According to the report of a traveller, the women in Egypt eat theBlaps sulcatacooked with butter, to make them fat. They are employed also against the ear-ache, the bite of scorpions, &c.
Another genus of the same family is theTenebrio(Fig. 542), of a blackish-brown, with the elytra striated, and of half an inch in length. The larvæ, the well-known meal-worms, live in flour; they are cylindrical, and of a light tawny colour (Fig. 542). The insect which is considered as a type of the tribe of thePimelidesis thePimelia bipunctata, which is common in the south of France.
We come now to the tribe of blistering beetles, of which the best known is the Cantharides (CantharisorLytta). These insects are generally of soft consistency, and their elytra very flexible. A fewremain constantly on trees. All are very brisk and active. When swallowed they are a dangerous poison, but are used in medicine for making blisters.
The Cantharides of commerce (Cantharis [Lytta] vesicatoria) are of a beautiful green, attain to a size of four-fifths of an inch, and are found on ash-trees, lilacs, and other shrubs. Commerce for a long time brought them from Spain, and some still come from that country; hence the common name ofSpanish fly. As they live in great numbers together, collecting them is easier and less expensivethan would be that of other species of the same family which are not gregarious, but which have the same medicinal properties. The presence of the Cantharides is manifested by the strong penetrating odour which they diffuse to some distance. When, by aid of this smell, they are discovered, generally settled on an ash, they are collected in the following manner:—Very early in the morning a cloth of light tissue is stretched out at the foot of the tree, and the branches are shaken, which causes the insects to fall (Plate XII.). These, numbed by the cold of the night, do not try to escape. When there is a sufficient quantity, the four corners are drawn up and the whole plunged into a tub of vinegar diluted with water. This immersion causes the death of the insects. They then carry them to a loft, or under a very airy shed. To dry them they spread them out on hurdles covered with linen or paper, and from time to time, to facilitate the operation, they are moved about, either with a stick or with the hand, which is more convenient; but it is then necessary to take the precaution of putting on gloves, for, if touched with the naked hand, they would cause more or less serious blisters. The same precaution must be observed in gathering them.
When the Cantharides are quite dry, they put them into wooden boxes or vessels of glass or earthenware hermetically sealed, and preserve them in a place protected from damp. With these precautions,they may be kept for a long while without losing any of their caustic properties. Dumeril made blisters of Cantharides which had been twenty-four years in store, and which had lost none of their energy. When dry, they are so light that a kilogramme contains nearly 13,000 insects. Aretius, a physician who flourished at Rome in the first century of our era, seems to have been the first to employ Cantharides, reduced to powder, as a means of vesication. Hippocrates administered them internally in cases of dropsy, apoplexy, and jaundice. But it is pretty nearly established that the Cantharides of the ancients were not the same species used at the present day; they were, probably, a kindred species, theMylabris chicorii. A blistering principle has been extracted from these insects, calledCantharadine. This organic product presents itself under the form of little shining flakes, without colour, soluble in ether or oil. One atom of this matter applied to the skin, and particularly to the lower lip, makes the epidermis rise instantaneously, and produces a small blister filled with a watery liquid. In spite of the corrosive principle which theCanthariscontains, it is attacked, like other dried insects, by theDermestesand theAnthrenus, which feast on them without suffering the smallest inconvenience.
XII.—Gathering Cantharides.
TheStylopidæ, for which Kirby,[122]in 1811, instituted a distinct Order, which he calledStrepsiptera, in allusion to the contortion of the elytra, and to which Latreille[123]subsequently applied the name ofRhipiptera, are, perhaps, the most anomalous of all insects. Great diversity of opinion has existed respecting their affinities; but modern systematists, with but few exceptions, concur in referring them to the OrderColeoptera, and locating them in proximity toMeloë. In the larva state, all the known species of the family inhabit the bodies of hymenopterous insects of the generaAndrena,Polistes, &c., in this particular resembling the dipterous genusConops, which inhabits the body of humble bees,[124]and apparently in no way inconveniencing their victims; a fact which has been accounted for on the supposition that their existence in the larva state is but short, and that their attacks being directed against the abdomen, and not the thorax, the seat of life in insects, their presence does not affect the activity of the victim. The larva has a soft fusiform body, surmounted by a somewhat globose head. While feeding, the head is towards the base of the abdomen; but on changing to a pupa, this position is reversed, and the head—at first of light brown, but which after a short time becomes black—thrust out between the plates of the abdomen.
The imagos, which are of small size, namely, about the eighth of an inch long, are found during May and June. They have four wings, but the anterior pair, of hard texture, somewhat resembling elytra, but hardly answering to them in structure, are very poorly developed, and curled round the front pair of legs, hence the name bestowed, by Kirby, from [Greek: strepssis], a twisting, and [Greek: pteron], a wing; the posterior wings are fully developed, and fold up like a fan, whence the Order received the name ofRhipipterafrom Latreille. The eyes, the facettes of which are few in number, are placed on a footstalk, whence the name of the genusStylops. The parts of the mouth connect the Strepsiptera with the mandibulated insects, although by some supposed to bear analogy by their functions to those parts in the Diptera. The male only is winged; the female is very like an apodal larva, the larva being an active hexapod.
The familyStylopidæis divided into four genera, of which two only,XenosandStylops, were described by Kirby in the essay referred to above. First,Xenos, from [Greek: xenos], a guest, the most prolific in species, of whichXenos Rossii, sometimes calledvesparum, may be taken asthe type. Secondly,Elenchus, of whichElenchus Walkeriis the type. Thirdly,Stylops(Fig. 543), parasitical on various species ofAndrenæ, of whichStylops Melittæ, having a fleshy abdomen and the wings longer than the body, may be considered typical: and lastly,Halictophagus, of which only one species, infestingHalictus æratus[125]namedHalictophagus Curtisii, is known to exist, and which makes its appearance in the month of August.
Fig. 543.—Stylops (magnified).Fig. 543.—Stylops (magnified).
These singular insects are found in various parts of the world—Europe, Australia, and America. They were discovered by Professor Peck almost simultaneously with Mr. Kirby's discovery in this country, and to whom he sent specimens of a species which has received the name ofXenos Peckiilately, in New Zealand and elsewhere.
Siebold, in 1843, having obtained some eggs, was able to observe the larvæ, and he soon discovered that the females of Stylops, one of the Strepsiptera, were blind, had no legs, and always retained the appearance of larvæ, and that they never quitted the bodies of those insects, in which they pass a parasitic existence. George Newport paid great attention to the history of these curious insects, and when he wrote his article, "Insecta," in the "Cyclopædia of Anatomy and Physiology," four distinct genera of these minute parasites had already been discovered. One of the largest species (Stylops Spencii) is scarcely more than two lines in length, while the smallest species yet known is not more than two-thirds of a line, or scarcely a line in breadth with its wings expanded. They undergo metamorphosis; and the males, when they have become perfect insects, fly and roam about, but the females are condemned to a perfectly quiet life. The head and the thoracic segments of the bodies of these last are united completely, but the abdomen, which is very large, always remains soft, so that the whole of the body only appears to be formed of two portions. They are ovo-viviparous insects, and the young larvæ escape as such from the body of the mother. They are active creatures, and, being furnished with long legs, crawl over the hairs and skin of the hymenopterous insect they are parasitic upon. They behave like the larvæ of Meloë and Sitaris, whose peculiar methods of life have been noticed in our description of the Coleoptera. Clinging on to a wasp or a bee, they are carried off, and finallyarrive in the nest or hive, as the case may be, and there they attack the larvæ. When once fixed upon the hymenopterous larvæ, they undergo a change of skin, and their shape then becomes totally different, and their legs are atrophied. But these parasites being exceedingly small, do not kill the larvæ; they suck their juices, after the manner of the Ichneumons, and do not interfere with the metamorphoses of the insects upon which they are parasitic. On the right hand, in the accompanying engraving (Fig. 544), there is a larvamuch magnified, lately born, and climbing upon the hair of one of the Hymenoptera, and on the left hand there is a perfect female insect, very much magnified, with ovo-viviparous larvæ within its abdomen, and between the two figures there is a representation of a larva of the natural size. It is evident, however, that ova may be expelled from the mother before they are hatched.
Fig. 544.—Female and Larva of Stylops.
Packard describes the curious history of the female Stylops, which he found parasitic on one of the bees. He caught the bee, and on examining it he noticed a pale reddish-brown triangular mark on the abdomen, and this was the flattened head and thorax of a female Stylops. The creature is included in the body of the bee, and is nourished by its juices. The head and thorax of the parasite were noticed to be soldered into a single flattened mass, the baggy hind body being greatly enlarged, like that of the female white ant. On carefully drawing out the whole body from the bee the mass was found to be very extensible, soft, and baggy, and on examining it under a high power of the microscope, multitudes of very minute larvæ were observed, and they began to issue out from the body of the parent all alive, and not as eggs. The male of thisStylops childreniis totally unlike its partner, having large hind wings, and being able to fly, as has already been noticed. It appears, then, that the larvæ are hatched or crawl out of the body of the mother on to the body of the bee, and are then transported to its nest; then they enter the body of the bee larva, and live upon its fatty matter. The male Stylops is turned into a pupa within the bee, and so is the female; but after the second metamorphosis the male flies off, leaving his wingless partner imprisoned for life, and she usually dies immediately after giving birth to her myriad offspring (Packard). The female respires by peculiarly arranged tracheæ, and absorbs nourishment through her skin as well as by means of an alimentary canal, which ends in a blind sac. All the beauties of the female, so far as they are visible to the male, consist in the tiny patch which appears just without the body of the unfortunate bee, and the ova collect in a space which opens between the united head and body and the abdomen.
The genusMylabriscorresponds most in structure, in appearance, and in properties, toCantharis, whose place they take in the East, in China, and in the south of Europe. They are found in clusters on the flowers of chicory, thistles, &c. TheMylabris chicorii, common enough in France, especially in the south, is of small size, whilst the other species are rather large. It is black, hairy, with a large yellowish spot at the base of each elytron, and two transverse bands of the same colour.
Another genus of this family isMeloë, with very short elytra, and without wings. They walk slowly and with difficulty on low plants, the female dragging along an enormous abdomen filled with eggs. They are generally observed in spring. In Germany they give them the name ofMaiwurm(Mayworm). Their succulence would expose them, without doubt, to the voracity of birds and of insect-eating Mammifers if they had not the power of exuding at will, in the moment of danger, from all their articulations, an unctuous humour of a reddish-yellow colour, the odour and probably also the caustic properties of which repel the aggressor. The females lay their eggs underground, and out of these come forth larvæ of a strange shape. Swallowed by cattle, they cause them to swell and die. It is for this reason that Latreille has given it as his opinion that these insects are theBuprestisof the ancients, of which the law of Cornelius speaks, "Lex Cornelia de sicariis et veneficis." But the name ofBuprestiswas applied by Linnæus to a genus of which we shall treat farther on, and it has been generally adopted by naturalists.
The commonest among theMeloësis theMeloë proscarabæus, which is to be found in abundance, in the month of April, in the meadows near the bridge of Ivry in the environs of Paris. The metamorphoses of the insects of this family had remained for a longtime surrounded with an impenetrable veil of mystery, but the researches of Newport in England, and of M. Fabre (of Avignon) in France, has made known in our days, phases, extremely curious, under which are accomplished the metamorphoses of theMeloë cicatricosus, and of theSitaris humeralis, a species which belongs to the same family.[126]These observations, of which we are about to give a rapid summary, will probably help towards unravelling the first states ofCantharis.
TheSitaris humeralis(Fig. 545) takes no nourishment when arrived at the perfect state. When the female has been impregnated, she lays at the entrance of the nest of a solitary bee from 2,000 to 3,000 small whitish eggs, stuck together in shapeless masses. A month afterwards there come out of these eggs very small larvæ, of a shiny dark green, hard-skinned, armed with strong jaws, and long legs and antennæ (Fig. 546). These are the first larvæ. They remain motionless, and without taking food, till the following spring. At this period are hatched the male bees, which precede the appearance of the females by a month. As the bees come out of their nests, these larvæ hook themselves on to their hairs, and pass them to the females, at the coupling period. When the male bees have built the cells, and furnished them with honey, the female, as we know, deposits in each an egg. Immediately the larvæ of theSitarislet themselves fall on these eggs, open them, and suck their contents. Then they change their skin, and the second larva appears. This one gets into the honey, on which it feeds for six weeks. It is blind, whereas the first larva was provided with four eyes, no doubt to enable it to see the bees which were to serve as its conductors, in likemanner as the companions of Ulysses watched the sheep of Polyphemus, so as to escape out of the cave in which they were retained as prisoners. A few days later, and this second larva contracts, and detaches from its body a transparent skin, which discloses a mass, at first soft, which very soon hardens, and becomes of a bright tawny colour; it is called thepseudo-nymph(Fig. 547). It goes through the winter in this state. In the spring comes forth a third larva (Fig. 548), resembling the second. This one does not eat, and moults after a time. It very soon changes into an ordinary pupa (Fig. 549), of a yellowish-white, from which comes forth the adultSitaris, which lives only a few days, to ensure the propagation of its species, as is observed in the case of theEphemeræ. The larvæ of theSitarishad for a long time been remarked clinging on to the hairs of theAnthophoras, but they were always taken forAcari, and they had been described as such.
Fig. 550.—Lampyris noctiluca (male and female).Fig. 550.—Lampyris noctiluca (male and female).
TheLampyridæhave the elytra weak and soft, like the insects of the preceding tribe. In their perfect state they frequent flowers. The larvæ are carnivorous, attacking other insects or worms. It is to this group that theLampyris noctiluca, or glow-worm, which one sees shining during summer nights on grass and bushes, belongs. It has the power of making this natural torch shine or disappear at will.
The luminous properties with which these insects are endowed have for their object to reveal their presence to the opposite sex, for the females alone possess these properties. In the same way as sounds or odours exhaling from some insects attract the one towards the other sex, so with theLampyrisa phosphorescent light shows the females to the males. The seat of the phosphorescent substance varies according to the species. It exists generally under the three last rings of the abdomen, and the light is produced by the slow combustion of a peculiar secretion. It has been stated that it is evolved quickly when the animal contracts its muscles, eitherspontaneously or under the influence of artificial excitement. Some chemical experiments have been made to ascertain the nature or the composition of the humour which produces this strange effect; but up to this moment, they have only enabled us to discover that the luminous action is more powerful in oxygen, and ceases in gases incapable of supporting combustion. In the most common species, theLampyris noctiluca, or glow-worm, the phosphorescence is of a greenish tint: it assumes at certain moments the brightness of white-hot coal.
The females have no wings, while the males have them, and possess very well-developed elytra. The females resemble the larvæ much, only they have the head more conspicuous, and the thorax buckler-shaped, like the male. The larvæ feed on small molluscs, hiding in the snails' shells, after having devoured the inhabitant. They also possess the phosphorescent property in a less degree than the adult females. The female pupa resembles the larva; the pupa of the male, on the contrary, has the wings folded back under a thin skin. The perfect insect appears towards the autumn.
The Glow-worm (Lampyris noctiluca,Fig. 550) is of a brownish yellow. It is common in England. In a kindred species, theLuciola Italica, the two sexes are winged, of a tawny-brown, and equally phosphorescent. They are met with in great numbers in Italy, and the lawns are covered with them. Other insects of this family are without the faculty of emitting light; as, for example, the genusLycus, of brilliant colours, which are met with in Africa and India. One of the finest is theLycus latissimus.
Drilusis another genus, comprising insects of very singular habits. The type is theDrilus flavescens. The male—a quarter of an inch long, black and hairy, with elytra of a testaceous yellow, and with pectinated antennæ—for a long time was alone known. The female—from ten to fifteen times as large, without wings and elytra, of a yellowish brown—was not discovered till much later, having apparently nothing in common with the male in shape or colour. The metamorphoses of these curious insects are now perfectly understood. Mielzinsky, a Polish naturalist established at Geneva, found theDrilusin the larva state in the shell of theHelix nemoralis. These larvæ devour the snail whose dwelling they occupy, as do the larvæ of theLampyris. Mielzinsky saw them emerge, but obtained only females, which differed scarcely at all from the larvæ from which they proceeded. He made a separate genus of them, under the denomination ofCochleoctonus, and called the speciesVorax. Later,Desmarest resumed these observations. He provided himself, at the Veterinary College of Alfort, with a number of shells of theHelixfilled with the same larvæ. He saw come out of them, not onlyCochleoctoni, but alsoDrili, and he watched their coupling. It was then proved, by this unanswerable argument, that these two insects, so unlike each other, belong to the same species.
The larva of theDrilus flavescensfixes itself upon the shell of the snail by a sort of sucker, like a leech. Little by little it slips in between the mollusc and its house, and devours it entirely. To change into a pupa, it shuts up the entrance to the shell with its old skin; and when arrived at the perfect state, quits the shell which served it as a temporary dwelling. The females of theDrilus flavescenstake refuge under stones and dry leaves, or crawl slowly along the ground; whilst the males, which fly with great ease, are on the plants and brushwood. These insects are not rare in the environs of Paris. M. H. Lucas has observed, in Algeria, near to Oran, another curious species, theDrilus Mauritanicus. The larva of this insect lives at the expense of the animal of theCyclostoma Volzianum, which closes the entrance to its shell with a covering of some calcareous substance. It fixes itself on the edge of the shell, with the aid of its sucker, and directs its strong mandibles to the side on which the snail is obliged to raise the covering, either to breathe the air or to walk. In this position it has the patience to wait formany days at the door. The snail puts off for as long a time as he is able the fatal moment. But when, overcome by hunger or nearly stifled in his prison, he decides at last to open the door, theDrilusprofits immediately by this opportunity, and cuts the muscle which keeps back the foot of the snail. The breach being made, nothing more opposes itself to the entrance of the enemy. He slips in, and sets to work to eat at his leisure the unfortunate inoffensive mollusc, which affords him board and lodging. ThePtilodadylides, theEucinetides, and theCebrionidesbelong to the same family. The first is exotic.
TheElateridæare rather large insects, often of hard texture, having the prosternum prolonged into a point (Figs.551and552), and the antennæ indented saw-wise. They have the power of jumping when placed on their backs, and of alighting again on their legs. Hence their name ofElater(derived from the same root as the wordelastic). They produce, in leaping, one sharp rap, and often knock many raps when they are prevented from projecting themselves. This is the mechanism which permits the skip-jack to execute these movements. It bends itself upwards by resting on the ground by its head and the extremity of the abdomen, and then it unbends itself suddenly, like a spring. The point at the end of the thorax penetrates into a hollow of the next ring; the back then strikes with force against the plane on which it rests, and the animal is projected into the air. It repeats this manœuvre till it finds itself on its belly, for its legs are too short to allow of its turning over. Its structure supplies it with the means and the strength of rebounding as many times as it falls on its back, and it can thus raise itself more than twelve times the length of its body.
The larvæ of the genusElateridæ(Fig. 553) are cylindrical, with a scaly skin and very short legs. They live in rotten wood or in the roots of plants. According to M. Goureau, they pass five years in this state.
The larvæ of the genusAgriotesoccasion considerable damage to wheat-fields. They have much resemblance to the meal-worm, or larva of theTenebrio. TheTetralobidesare the largest of theElateridæ, attaining to a length of two inches; and are inhabitants of Africa and Australia.
In America are found phosphorescentElateridæ. These are thePyrophori, which the Spaniards of South America call by the name ofCucuyos. They have, at the base of their thorax, two small, smooth, and brilliant spots, which sparkle during the night; the rings of the abdomen also emit a light. They give light sufficient toenable one to read at a little distance from them. ThePyrophorus noctilucus(Fig. 554) is very common in Havannah, in Brazil, in Guyana, in Mexico, &c., and may be seen at night in great numbers, amongst the foliage of trees. At the time of the Spanish conquest, a battalion, just disembarked, did not dare to engage with the natives, because it took the Cucuyos which were shining on the neighbouring trees for the matches of the arquebuses ready to fire. "In these countries," says M. Michelet, "one travels much by night, to escape the heat. But one would not dare to plunge into the peopled shades of the deep forests if these insects did not reassure the traveller. He sees them shining afar off, dancing, twisting about; he sees them near at hand on the bushes by his side; he takes them with him; he fixes them on his boots, so that they may show him his road and put to flight the serpents; but when the sun rises, gratefully and carefully he places them on a shrub, and restores them to their amorous occupations. It is a beautiful Indian proverb that says, 'Carry away the fire-fly, but restore it from whence thou tookest it'"[127]The Creole women make use of the Cucuyos to increase the splendour of their toilettes. Strange jewels! which must be fed, which must be bathed twice a day, and must be incessantly taken care of, to prevent them from dying. The Indians catch these insects by balancing hot coals in the air, at the end of a stick, to attract them, which proves that the light which these insects diffuse is to attract. Once in the hands of the women, the Cucuyos are shut up in little cages of very fine wire, and fed on fragments of sugar-cane. When the Mexican ladies wish to adorn themselves with these living diamonds, they place them in little bags of light tulle, which they arrange with taste on their skirts. There is another way of mounting the Cucuyos. They pass a pin, without hurting them, under the thorax, and stick this pin in their hair. The refinement of elegance consists in combining with the Cucuyos, humming-birds and real diamonds, which produce a dazzling head-dress. Sometimes, imprisoning these animated flames in gauze, the graceful Mexican women twist them into ardent necklaces, or else roll them round their waists, like a fiery girdle. They go to the ball under a diadem of living topazes, of animated emeralds, and this diadem blazes or pales according as the insect is fresh or fatigued. When they return home, after thesoirée, they make them take a bath, which refreshes them, and put them back again into the cage, which sheds during the whole night a soft light in the chamber. In 1766, a Cucuyo, brought alive fromAmerica to Paris, probably in some old piece of wood which happened to be on the vessel, caused great terror to the inhabitants of the Faubourg St. Antoine, when they saw it flying in the evening, glittering in the air. In 1864 a number of Cucuyos were brought from Mexico to Paris by M. Laurent, captain of the frigateLa Floride. An experiment, made in the laboratory of the École Normal, showed that the spectrum of their light is continuous, without any black rays; it differs, besides, from the spectrum of the solar light by a greater intensity of the yellow colour. The light is produced probably as it is in the case of theLampyris, by the slow combustion of a substance secreted by the animal. The Cucuyo can, nevertheless, at will, increase or diminish the splendour of this light by means of membranes which it superposes, like screens, in front of the phosphorescent bumps which it has on its thorax.
In the Indies, and in China, the women use for dressing their hair with, or as ear-rings, another Coleopteron of the same tribe, which begins even to be employed for this purpose by the women of the south of France. It is aBuprestis, of splendid colours, and of metallic brightness. Linnæus, as we said above, gave to it, wrongly, the name ofBuprestis, which among the ancients served to designate a very different insect, theMeloë, of the family of theCantharidæ; but modern naturalists have allowed this illegitimate title.
TheBuprestidæwalk heavily, but fly with the greatest ease during the heat of the sun, and settle on the trunks of trees exposed to itsrays. In Europe, and especially in the North, they are very rare, and of very small size. They must be looked for on birch-trees, whose white colour seems to attract them. In the hottest parts of the world they are very abundant, of large dimensions, and adorned with sparkling colours. They do not jump, and are not endowed with the phosphorescent property. Their larvæ have no legs, are elongate, whitish, of a fleshy consistency, with the first ring of their bodies very much broadened. They live in the trunks of trees, between the bark and the wood, hollowing out for themselves irregular galleries, and remaining sometimes in this state for ten years before metamorphosing. Laporte de Castelnau and Gory have described and made drawings of about 1,300 species ofBuprestidæ.Fig. 555represents theBuprestis imperialis. TheBuprestis albosparsa, the generaJulodis, theChrysochroas, and theTrachysbelong also to the great family ofBuprestidæ. TheCleridæare connected with the preceding. They have the thorax narrower than the elytra, and rather long; their integuments are less solid than those of theElateridæand theBuprestidæ. The latter are phytophagous, the former carnivorous. The principal type of this family is theClerus formicarius, russety, with the head and legs black, whose larva lives at the expense of the larvæ of the weevil. Another genus, theNecrobia, which lives on dried animal matter, has become celebrated, as it was the cause of the salvation of the greatest entomologist of France. The name ofNecrobia(from [Greek: nekros] and [Greek: biôs]) does not mean "which lives on dead bodies," but it means "life in death." Here is the story of which this name is destined to preserve the remembrance, and which Latreille himself has related in his "Histoire des Insectes." Before 1792, Latreille was known only from some memoirs which he had published on insects. He was then priest at Brives-la-Gaillarde, and was arrested with the curés of Limousin, who had not taken the oath. These unfortunates were then taken to Bordeaux in carts, to be transported to Guyana. Arrived at Bordeaux in the month of June, they were incarcerated in the prison of the Grand Séminaire till a ship should be ready to take them on board. In the meanwhile, the 9th Thermidor arrived, and caused the execution of the sentence which condemned the priests who had not taken the oath to transportation to be for a while suspended. However, the prisons emptied themselves but slowly, and those who had been condemned had none the less to go into exile, only their transportation had been put off till the spring.
"Latreille remained detained at the prison of the Grand Séminaire. In the same chamber which he occupied there was at thetime an old sick bishop, whose wounds a surgeon came each morning to dress. One day as the surgeon was dressing the bishop's wounds, an insect came out of a crack in the boards. Latreille seized it immediately, examined it, stuck it on a cork with a pin, and seemed enchanted at what he had found.
"Is it a rare insect, then?" said the surgeon.
"Yes," replied the ecclesiastic.
"In that case you should give it to me."
"Why?"
"Because I have a friend who has a fine collection of insects, who would be pleased with it."
"Very well, take him this insect; tell him how you came by it, and beg him to tell me its name."
The surgeon went quickly to his friend's house. This friend was Bory de Saint Vincent, a naturalist who became celebrated afterwards, but who was very young at that time. He already occupied himself much with the natural sciences, and in particular with the classing of insects. The surgeon delivered to him the one found by the priest, but in spite of all his researches, he was unable to class it.
Next day the surgeon having seen Latreille again in his prison, was obliged to confess to him that in his friend's opinion this Coleopteron had never been described. Latreille knew by this answer that Bory de Saint Vincent was an adept. As they gave the prisoner neither pen nor paper, he said to his messenger, "I see plainly that M. Bory de Saint Vincent must know my name. You tell him that I am the Abbé Latreille, and that I am going to die at Guyana, before having published my 'Examen des Genres de Fabricius.'"
Bory, on receiving this piece of news, took active steps, and obtained leave for Latreille to come out of his prison, as a convalescent, his uncle Dayclas and his father being bail for him, and pledging themselves formally to deliver up the prisoner the moment they were summoned to do so by the authorities. The vessel which was to have conducted Latreille to exile, or rather to death, was getting ready whilst these steps were being taken, and while Bory and Dayclas were obtaining leave for him to come out of prison. This was quite providential, for it foundered in sight of Cordova, and the sailors alone were able to save themselves. A little time afterwards his friends managed to have his name scratched out from the list of exiles. It is thus that theNecrobia ruficolliswas the saving of Latreille.
The tribe of weevils is even much more numerous than that of theElateridæand theBuprestidæ. One may know them by their head prolonged into a snout or trunk, by their rudimentary mouth, and by their elbowed antennæ. About twenty thousand species are said to exist. They feed on vegetables. Their larvæ are soft, whitish worms, without legs, with very small heads, and live in the interior of the stalks or seeds of plants, often occasioning enormous damage. They are one of the plagues of agriculture. Each of our dry vegetables, each variety of our cereals, has in this immense family its particular enemy.
First are theBruchi. The Pea Weevil (Bruchus pisi,Fig. 556), which is brown with white spots, comes out of the pea at the end of the summer. The female lays her eggs on peas which are ripe, and still standing, in which the larva scoops out a habitation, and then makes its exit by a circular hole (Fig. 557). It remains at rest all the winter, and is not hatched till towards the following spring. The Bean Weevil (Bruchus rufimanus) marks each bean with many black spots. The vetch has also its specialBruchus. The Wheat Weevil (Calandra granaria), of a darkish brown, lays its eggs on the grains, of which the larvæ then eat the interior. A host of ways of getting rid of the weevil have been proposed. The best means is to store corn properly, and to keep the heap well aired. Let us mention further, the Clover Weevil, belonging to the genusApion, the Weevil of the Rape (Ceutorhynchus brassicæ), the Turnip Weevil, &c., &c.
All vegetables, the vine, fruit trees, the ash, pines, &c., are eaten by some weevil or other. As an example we give a figure of the spottedPissodes pini, which, as the figure shows, takes the precaution of cutting half through the young stems and the stalks of the buds of the pine, "so as," says M. Maurice Girard,[128]"that the sap flowsonly with difficulty into the withered organ, and cannot suffocate the young larvæ."