The Insect World / Being a Popular Account of the Orders of Insects; Together with a Description of the Habits and Economy of Some of the Most Interesting Species

Fig. 448 represents the Stag Beetle (Lucanus cervus); Fig. 449, an exotic species, the Lucanus (Homoderus) Mellyi, from the Gabon; Fig. 450 the Lucanus bellicosus; and Fig. 451 another exotic species from Celebes, Dorcus Titan.

The Syndesus cornutus (Fig. 452) of Tasmania, and the Chiasognathus Grantii, from the coast of Chili (Fig. 453), of a beautiful golden green, shot with copper, belong to genera akin to Lucanus.

We arrive now at the tribe of Silphales, which are still more useful to man than the Dung Beetles (Scarabæidæ), since many of them disencumber the soil of the carcases of animals in a state of putrefaction. The most remarkable insects of this tribe are the Histers, the Silphas, properly so called, and the Necrophora.

The Histers are small insects, to be recognised by their body being almost round, smooth, and shining, with the elytra marked with striæ, and their mandibles pretty well developed. They attain to a length of about a fifth of an inch. The Silphæ, thus named on account of their broad and rounded form, are of a large size (about half to three-quarters of an inch), of a dark colour, and exhale a sickly odour. When seized, they disgorge a blackish liquid. They introduce themselves under the skin of the carcases of animals, and devour their flesh to the very bone. The larvæ, flat and serrated, live like the adults, in carrion. The commonest species is the Silpha obscura, of an intense black, delicately dotted. Two species found in England and in the environs of Paris, Silpha quadripunctata and the Silpha thoracica, climb trees and attack caterpillars. It appears to be certain that the larva of the Silpha obscura does a great deal of damage to beet-root, whose leaves it devours. The Necrodes come very near to the Silphæ. They are distinguished from them by having the hind legs larger. Only one, Necrodes littoralis, occurs in England. Fig. 459 represents the Necrodes lacrymosa, from Australia. The Necrophori, or Grave-diggers, are honest undertakers, who carefully bury carcases left on the soil. As soon as they smell a field-mouse, a mole, or a fish in a state of decomposition, they come by troops to bury it, getting under the carcase, hollowing out the ground with their legs, and projecting the rubbish they dig out in all directions. Little by little the carcase sinks; at the end of twenty-four hours it has generally disappeared into a hole five inches in depth, but the Necrophori sink it still lower—as far as from seven to ten inches below the surface. They then mount it, cast the earth down into the grave so as to fill it, and the females lay their eggs in the tomb, where the larvæ will find an abundance of food. When the ground is too hard to be dug, the Necrophori push the carcase further, till they find permeable soil. A mole has been run through with a stick, or else tied by a string, to see how the Necrophori would get over the difficulty. They scooped out the soil underneath the stick, and cut through the string, and the mole was buried in spite of the obstacles. Fig. 460 represents a troop of Necrophori burying a small rat.

The Necrophorus vespillo (Fig. 461) is variegated with yellow and black; the Necrophorus Germanicus (Fig. 462) is larger, quite black, and rarer. All these insects exhale a disagreeable musky smell. Their bodies are often covered with parasites, which are carried along by them by hooking on to their hairs, and which make use of the Necrophorus as a vehicle in which they get their food.

We see frequently on roads the Staphylinus olens (Figs. 463 and 464), which, when it finds itself attacked, raises its abdomen, and thrusts out two little whitish bladders, which pour out a volatile liquid. Its larva lives under stones, and its habits are the same as those of the adult insect. It is very carnivorous, and very active, and often attacks those of its own kind. The Staphylinus hirtus (Fig. 466) resembles at a distance a humble-bee, on account of its long yellow hairs. The Staphylinus maxillosus (Fig. 465) has black and white hairs. The genera Pselaphus and Claviger, akin to the above, contain little insects which live as parasites in the nests of ants. The Pselaphus Heisii (Fig. 467), less than a line long, lives on the débris of reeds, on the borders of marshes.

The Claviger foveolatus (Fig. 468) is met with in the nest of a little yellow ant, which takes as much care of it as of its own progeny, because the Claviger secretes a liquid very much appreciated by ants, who are continually occupied in licking its back.

The Dermestidæ attack by preference the tendons and the skins of carcases. A few of the insects of this family are the plague of our collections and the furriers. They devour a quantity of dry substances—skins, feathers, catgut, hair, objects made of tortoise-shell, the dried bodies of insects, &c. Some other Dermestidæ feed on animal matter still fresh: such is the Bacon Beetle, Dermestes lardarius (Fig. 469), which is to be met with in some dirty pork-shops. It is black, with the base of its elytra tawny and marked with three black spots. The larvæ are covered with a russety hair; they eat bacon, skins, and also attack each other. The perfect insect does no damage. Like all the Dermestidæ, it counterfeits death when handled. The Dermestes vulpinus, of a tawny grey, injures furs; and the Hudson's Bay Company, whose storehouses in London were infested by this insect, offered a reward of £20,000 for a means of destroying this insect. The furriers have also cause to dread the Attagenus pellio (Fig. 470), whose larva, covered with yellowish hairs, has at its extremity a sort of broom, which assists it in moving.

The Anthrenus museorum, the fifteenth of an inch in length, black, with three grey bands, drives collectors to despair, for its larva destroys their collections. It is covered with grey and brownish hairs, which it bristles up the moment it is touched. The perfect insect feeds on flowers, and counterfeits death when seized. All possible means have been tried for getting rid of the Anthrenus by placing in the collection camphor, benzine, tobacco, sulphur, &c., but benzine very soon destroys them.

The Hydrophili, very different to the group which we shall presently consider, are herbivorous, and are to be found on the leaves of aquatic plants. The Hydrophilus piceus (Fig. 471), which attains to an inch in length, is common in our fresh waters. It must not be seized without taking precautions, as its breast is provided with a strong point, which pierces the skin. It draws in air by thrusting its antennæ out of the water, and placing them against its body, the bubbles of the air, which get involved in a sort of furrow, slip under the body, and fix themselves to the hair, in such a manner that the animal seems to be clothed in pearls. It is thus the air reaches the spiracles. The female of the Hydrophilus is sometimes seen clinging to aquatic plants, head downwards, forming her cocoon, terminated by a long pedicle, in which she places her eggs, by means of the two bristles situated at the extremity of the abdomen (Fig. 472). After having drawn this after her for some time, she leaves it to itself in calm water. At the end of a fortnight there come out from it little brown larvæ, very active, which ascend the water plants. These larvæ are at the same time herbivorous and carnivorous. They live on plants and small molluscs, which they seize from underneath, and whose shell they break by pressing them against their back, to extract from it the animal. If attacked, they emit a black liquid, which discolours the water, and enables them to escape. At the end of two months the larva comes out of the water, and burrows into the ground to undergo its metamorphosis into a pupa (Fig. 473), which becomes a perfect insect a month afterwards. The latter gets its colour little by little, and comes out of the ground at the end of twelve days. According to M. Dumeril, the intestine of the larva grows gradually longer and longer, and its diet becomes that of herbs, the adult preferring vegetable food to animal matter. It is at the end of summer that the Hydrophilus piceus becomes perfect, and it passes the winter in a state of torpor at the bottom of the water. The females lay in the month of April. A small species, Hydrous caraboides, is commoner than the large one; its body is more rounded behind.

We are now going to consider a series of aquatic and carnivorous insects; the Dytisci, Water Beetles, the Cybisters, and the Gyrinidæ, or Whirligig Beetles. These are perfect corsairs, whose rapacity even exceeds that of many of the land Coleoptera. Not contented with devouring one another, when pressed by hunger, with attacking especially the larvæ of all aquatic insects, such as the Libellulæ and Ephemeræ, they feed also on molluscs, on tadpoles, and on small fish. It is easy to rear them in captivity. If confined in a small aquarium, their habits would be much more amusing than a few golden fish, which one meets with everywhere, and which are only good enough to amuse European Schaabahams. Care must be taken to cover the aquarium at the top with gauze, to prevent the perfect insects from escaping. This tribe is not very numerous nor varied in its forms. An oval body, legs curved and widened into oars, provided with hairs, distinguish the insects which compose it. They imbibe air at the surface of the water.

The most carnivorous of this group are the Dytisci and the Cybisters. They may be called the sharks of the insect world. Nothing which lives in the water is safe against the voracity of the Dytiscus. They attack small molluscs, young fish, tadpoles, larvæ of insects, and suck greedily the bits of raw meat which are thrown to them. They may be kept in an aquarium for many years by feeding them on animal matter. Their oval-shaped body, with its sharp sides, permits them to cut through the water with great ease—the hind legs serving as oars. They are to be found in stagnant waters during the greatest part of the year, but principally in autumn. During the winter they bury themselves in the mud and under moss. The females lay their eggs in the water. The larvæ are long, swelling out at the middle, furnished with hairs, and grow rapidly. To undergo their metamorphosis into pupæ they bury themselves in the earth.

The perfect insects are amphibious, and fly from one pond to another to satisfy their voracious appetites. The most common species of this genus is the Dytiscus marginalis (Fig. 474), of a dark greenish brown, yellowish on the sides. The elytra of the male are smooth; those of the female are fluted. The front leg of the male is provided with suckers. The larva is brown; the pupa of a dirty white.

The Dytiscus marginalis sometimes attacks Hydrophilus piceus. It pierces it between the head and the thorax, that is, in the weak point of the cuirass, and devours it, in spite of its being the stronger. The largest of the Dytisci, the Dytiscus latissimus (Fig. 476), is almost confined to the north of Europe. The Cybisters abound especially in warm countries. The Cybister Rœselii (Fig. 477), a European species, has the reputation of having been taken in England. This group contains also a great number of insects more or less resembling the preceding in their conformation and habits. We will confine ourselves to representing a few by figures.

The Gyrinidæ, which come very near to the Dytiscidæ, like water which is clear and a little agitated. They are small black insects, living in troops, and which swim with rapidity, describing incessantly capricious circles, which has gained for them the name of "Whirligigs." They are remarkable for the disposition of their eyes, which are double; so that the Gyrinidæ seem to have four eyes. The lower ones look into the water and watch for the prey or the fish that advances as an enemy; whilst the upper eyes look upwards towards the air, and warn the insect of the approach of enemies from above. To escape from fish, the Gyrinus jumps out of the water, and also makes use of its wings; to escape from birds it dives rapidly. This activity, and this double sight, make the capture of the Gyrini a task of great difficulty. They must be caught with a net. At the moment of being seized they emit a milky and fœtid liquid.

The females lay their eggs end to end, on the leaves of aquatic plants. The larvæ are long and narrow, and of a dirty white. They come out of the water at the end of the summer, and form for themselves a cocoon on the plants bordering the banks. After a month, the perfect insect is hatched, and plunges into the water. The Gyrinus striatus (Fig. 496) is found in the waters of southern Europe.

All these species are of small size, and do not exceed a fifth of an inch in length; but in the tropics we find Gyrini two-thirds of an inch long. One of these species, distinctus, exists in the little lake of Solazies, in Réunion Island, noted for its mineral waters. The visitors amuse themselves by fishing for this insect with a line baited with a bit of red cloth, which it attacks. It is found also in a mineral spring in Algeria. The Epinecti (Fig. 498) are large Gyrinidæ from Brazil, with very long front legs.

The carnivorous land insects par excellence—those which are most formidable, on account of their ravages and voracity—are the Carabidæ. This family, one of the most numerous of the Order Coleoptera, consists of insects with long legs, and armed with powerful mandibles, suited for tearing their victims to pieces. They are the lions and the tigers of the Coleoptera, whilst the Necrophori and the Silphæ play the part of hyænas and jackals. The eyes of the Carabidæ are very prominent, which allows them to see their prey at a great distance. They take refuge under stones and under the bark of trees; but in fine weather they are also to be seen running along roads. Ardent and audacious, it is by no means rare to see them attacking species much bigger than themselves. The activity which distinguishes these insects is found also in their larvæ, which pursue living prey, instead of remaining shrouded in the midst of their food, like the larvæ of the Scarabæidæ.

These carnivorous insects are very numerous—a fortunate circumstance, considering the immense quantity of small noxious creatures, caterpillars, weevils, and an infinity of other parasites, the pests of agriculture, which they destroy. The popular prejudice, then, is to be regretted, which leads ignorant farmers to exterminate them. They ought, on the contrary, to be introduced into market gardens, as toads are, and as cats are into granaries. "The Carabidæ," says M. Michelet, "immense tribes of warriors, armed to the teeth, which, under their heavy cuirasses, have a wonderful activity, are perfect rural constabulary, day and night, without holidays or repose, protecting our fields. They never touch the smallest thing. They are occupied entirely in arresting thieves, and they desire no salary but the body of the thief himself." But ignorance destroys these useful hunters. Children, seduced by the richness of the elytra of the Carabi, amuse themselves in catching these vigilant protectors of our farms, without knowing the bad effect of what they are doing. Fortunately, education is spreading little by little in the country; the farmers begin to be awakened to their true interests, and to know how to distinguish the useful animals which it behoves them to preserve in their fields for the safeguard of their crops. In some places in France they have already made attempts to introduce the Carabidæ and the Cicindelidæ into gardens, and they have found them succeed very well.

The true Carabi are to be known by their oval convex body, their long antennæ, and elegantly-carved thorax. They are, in general, of more massive forms than the Cicindelidæ, which compose a kindred family. The latter form, in some sort, the vanguard and the light troops; the others, the heavy battalions. The Carabi coming out in general at night, or at least at twilight, and keeping themselves hidden under stones during the day, it is not easy to observe their manœuvres.

The Carabus auratus (Fig. 499), which abounds in fields and gardens on the Continent, may be considered as the type of this genus. It has elytra of a beautiful green, with three ribs, and the legs yellowish. When it is touched it disgorges a black and acrid saliva, and ejects from the abdomen a corrosive liquid of a disagreeable odour. It lives on the larvæ of other insects. It has been seen to attack even large insects, such as the cockchafer.

In England and the environs of Paris, Carabus violaceus (Fig. 500), whose dress, of a sombre colour, is surrounded by shades of red and violet, is met with. In the Pyrenees many Carabi with metallic reflections are found, whose beautiful colours are the delight of collectors; the Carabus splendens, the Carabus rutilans, &c. But the most beautiful insects of this tribe come from Siberia and the north of China. Let us mention, for example, the Carabus smaragdinus, of a beautiful grass-green; the Carabus Vietinghovii, of a beautiful blue black, bordered with azure, with a golden band, &c.

The Carabus Adonis (Fig. 502) is not rare in Alsace, and is found on the banks of streams.

The long flat larvæ of the Carabi live in the trunks of trees, among leaves, under moss, &c. They are active, and live on other insects. Fig. 504 represents the larva of the Carabus auronitens.

Another genus of the same family is Calosoma. They have wings under their elytra—the true Carabi have not—which they use in passing from one tree to another.

In the month of June is to be found on oak trees the beautiful Calosoma sycophanta (Fig. 508), the occasional occurrence of which in England is unquestionable; it is, however, presumed that the specimens have reached our shores from the Continent by flight, favoured by strong easterly winds. This insect is of a beautiful violet blue, having the antennæ and the legs black, and the elytra of a splendid golden green, with longitudinal streaks. According to Réaumur, the larva of the Calosoma often chooses a home in the nest of the Procession-Moth Caterpillar (Bombyx processionea), on oak trees, and it very soon rids the tree which is infested by them.

The Calosoma auropunctata is found in the south of France. Its larva (Fig. 507) devours snails, and establishes itself in their shells. These larvæ have been known to fill themselves so full of food as to become double their natural size, in which state they are sometimes devoured by those of their own species. A smaller kind, the Calosoma inquisitor, is very frequently to be met with in woods. Fig. 508 presents Calosoma sycophanta pursuing a Bombardier (Brachinus explodens), which squirts out a vapour of pungent odour.

In the countries of the south-east of Europe, and in Asia Minor, one finds enormous Carabidæ, the Procrustes and the Proceri, which attain nearly two inches in length, and whose integuments resemble very rough shagreen. One species alone is met with in France, the Procrustes coriaceus (Fig. 509). In Austria is found the Procerus gigas (Fig. 510).

The genus Omophron (Fig. 511) contains small, almost globular Carabidæ of a pale yellow, with green lines, and which live in the sand bordering rivers. The Nebrias in general prefer mountainous countries. The largest species, the Nebria arenaria (Fig. 512), is found all along the coast of the Mediterranean, and even on the western shores of France. But its colours grow paler as it advances northward on the African coast. It is of a bright yellow with black lines. The Nebrias hide themselves either under masses of seaweed cast up by the waves, or under the stumps of trees cast ashore by the sea. When they are deprived of their place of shelter, they run away with such rapidity that it is very difficult to catch them. In Senegal is found the genus Tefflus (Fig. 513), great black Carabidæ with fluted elytra.

Other kindred genera are—Damaster (Fig. 514), remarkable for elongated pointed elytra; Anthia (Fig. 515), which is met with in sand in Africa and in India, and whose head is armed in a formidable manner; and Campylocnemis, of which Schrœteri (Fig. 516), an Australian insect, of a bright black, attains to more than an inch and three quarters in length, and whose short serrated legs enable it to hollow out the ground. There is found on the coasts of the south of France a representative of this group in the Scarites lævigatus (Fig. 517), which conceals itself in a hollow, like the cricket, and devours everything which comes within its reach.

The innumerable tribe of Harpalidæ contains carnivorous beetles of very small size, sometimes of a bronze-green, sometimes black, either dull or shining, and which render great service to our gardens. Hidden under stones, in dry leaves, at the foot of trees, they attack a number of small insects, caterpillars, millepedes, &c., and thus exterminate a quantity of vermin. The Harpalus æneus (Fig. 518), which is seen shining in the midst of the paving stones like a little bronze plate, is found everywhere. The Galeritas (Figs. 519 and 520) are distinguished by their antennæ, which are thick at the base; they exhale a very strong odour: nearly all are peculiar to America. One of the most curious insects of this tribe is the Mormolyce phyllodes of Java (Fig. 521) whose elytra project in such a manner as to give it the appearance of a leaf. It lives under bark. The larva and the pupa (Fig. 522) resemble those of other genera of which we have been speaking.

The next great family of the tribe of carnivorous beetles is composed of the Cicindelidæ—slender insects, with large prominent heads, very long legs, and which are very active in their movements. The Cicindelidæ like sandy plains. When the sun shines they fly in a zig-zag manner, but their flight is not continued for long together. In dull weather they are to be seen running on the turf or hiding themselves in holes, and are met with on the sea-shore, where they are seen sometimes to pop up by hundreds. They live on flies and little shrimps, which abound on the sea-shore.