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undivided wing-sheaths, which at their extremities project a little beyond the abdomen; and the insect is totally destitute of real, or under wings. It is usually found in dark neglected places, beneath boards, in cellars, &c., and, if handled, especially if crushed, diffuses a very unpleasant smell. Pliny represents this beetle, when applied with oil extracted from the cedar, as an infallible remedy for otherwise incurable ulcers . Genus 8. Lampyris-Antenna filiform; feelers four; wing-cases flexible; thorar flat semi-orbicular; head concealed under the thorax; abdomen sides having papillary folds, the females mostly destitute of wings, and resembling larvae. The lampyris noctiluca, or glow-worm, is a highly curious and interesting animal. It is seen during the summer months as late as the close of August, if the season be mild, on dry banks, about woods, pastures, and hedgeways, exhibiting, as soon as the dusk of the evening commences, the most vivid and beautiful phosphoric splendor, in form of a round spot of considerable size. The animal itself, which is the female insect, measures about three-quarters of an inch in length, and is of a dull earthy-brown color on the upper parts, and beneath more or less tinged with rose-color; with the two or three last joints of the body of a pale, or whitish-sulphur color. It is from these parts that the phosphoric light above-mentioned proceeds, which is of a yellow color, with a very slight cast of green: the body, exclusive of the thorax, consists of ten joints or divisions. The larva, pupa, and complete female insect scarcely differ perceptibly from each other in general appearance, but the phosphoric light is strongest in the complete animal. The glowworm is a slow-moving insect, and in its manner of walking frequently seems to drag itself on by starts, or slight efforts as it were. The male is smaller than the female, and is provided both with wings and wing-sheaths: it is but rarely seen, and it seems, even at present, not very clearly determined whether it be luminous or not. The general idea among naturalists has been that the splendor exhibited by the female in this species is ordained for the purpose of attracting the male. This circumstance is elegantly expressed in the lines of Mr. Gilbert White, in his History of Selburne:— The chilling night-dews fall; away, retire. For sec, the glow-worm lights her amorous fire! Thus, ere night's veil had half obscured the sky, The impatient damsel hung her lamp on high : True to the signal, by love's meteor led, Leander hastened to his Hero's bed.

It is certain however that in some species of Jhis genus, the male as well as the female is luminous, as in the L. halica, which is a native of our own country also, though less common than in the more sultry countries of the south. Aldrovandus describes the winged glow-worm as having its wing-shells of a dusky color, and at the end of the body two brilliant fiery spots like •he flame of sulphur.

In Italy this flying glow-worm is extremely plentiful; and we are informed by Dr. Smith, £nd other travellers, that it is a very common practice for the ladies to stick them by wa of

ornament in different parts of their head-dress during the evening hours. The common or wingless glow-worm may be very successfully kept, if properly supplied with moist turf, grass, moss, &c., for a considerable length of time; and, as soon as the evening commences, will regularly exhibit its beautiful effulgence, illuminating every object within a small space around it, and sometimes the light is so vivid as to be perceived through the box in which it is kept. This insect deposits its eggs, which are small and yellowish, on the leaves of grass, &c. • Authors who have noticed the luminous o of the common female glow-worm,' says r. Kirby, “having usually contented themselves with stating that the light issues from the three last ventral segments of the abdomen, I shall give you the result of some observations I once made upon this subject. One evening, in the beginning of July, meeting with two of these insects, I placed them on my hand. At first their light was exceedingly brilliant, so as to appear even at the Junctions of the upper or dorsal segments of the abdomen. Soon after I had taken them, one withdrew its light altogether, but the other continued to shine. While it did this it was laid upon its back, the abdomen forming an angle with the rest of its body, and the last or anal segment being kept in constant motion. This segment was distinguished by two round and vivid spots of light, which, in the specimen that had ceased to shine, were the last that disappeared, and they seem to be the first parts that become luminous when the animal is disposed to yield its light. The penultimate and ante-penultimate segments, each exhibited a transverse band of yellow radiance, terminated towards the trunk by an obtusely-dentated line, agreener and fainter light being emitted by the rest of the segment.’ Though many of the females of the different species of lampyris are without wings and even elytra (in which circumstance they differ from all other apterous coleoptera) this is not the case with all. The female of L. Italica, a species common in Italy, is winged; and when a number of these moving stars are seen to dart through the air, in a dark night, nothing can have a more beautiful effect With respect to the remote cause of the lumi-. nous property of insects, continues this interesting writer, philosophers are considerably divided in opinion. The disciples of modern chemistry have in general, with Dr. Darwin, referred it to

the slow combination of phosphorus secreted

from their fluids by an appropriate organisation; and entering into combination with the oxygen supplied in respiration. This opinion is very plausibly built upon the ascertained existence o

phosphoric acid as an animal secretion; the great resemblance between the light of phosphorus in slow combustion and animal light; the remarkably large spiracula in glow-worms; and upon the statement that the light of the glow-worm is rendered more brilliant by the application of heat and oxygen gas, and is extinguished by cold and by hydrogen and carbonic acid gases. From these last facts Spallanzani was led to regard the luminous matter as a compound of hydrogen and carbureted hydrogen gas. Carradori having found that the luminous portion of the belly of the Italian glow-worm (lampyris Italica) shone in vacuo, in oil, in water, and when under other circumstances where the presence of oxygen gas was precluded, with Brugnatelli ascribed the property in question to the imbibition of light separated from the food or air taken into the body, and afterwards secreted in a sensible form. Lastly, Mr. Macartney having ascertained, by experiment, that the light of a glow-worm is not diminished by immersion in water, or increased by the application of heat; that the substance affording it, though poetically employed for lighting the fairies' tapers, is capable of inflammation if applied to the flame of a candle or redhot iron; and when separated from the body exhibits no sensible heat on the thermometer's being applied to it—rejects the preceding hypotheses as unsatisfactory, but without substituting any other explanation; suggesting, however, that the facts he observed are more favorable to the supposition of light being a quality of matter than a substance. Some experiments made by the Rev. R. Sheppard on the glow-worm are worthy of being recorded. One of the receptacles being extracted with a pen-knife continued luminous; but on being immersed in camphorated spirit of wine, became immediately extinct. The animal, with one of its receptacles uninjured, being plunged into the same spirit, became apparently lifeless in less than a minute; but the receptacle continued luminous for five minutes, the light gradually disappearing. Having extracted the luminous matter from the receptacles, in two days they were healed, and filled with luminous matter as before. He found this matter to lose its luminous property, and become dry and glossy like gum, in about two minutes; but it recovered it again on being moistened with saliva, and again lost it when dried. When the matter was extracted from two or three glowworms, and covered with liquid gum-arabic, it continued luminous for upwards of a quarter of an hour." Mr. Murray remarks that, in a box in which glow-worms were kept, five luminous specks were found secreted by the animal, which seemed to glow, and were of a different tinge of light. One put into olive-oil at eleven, P. M. continued to

yield a steady and uninterrupted light until five

o'clock the following morning, and then seemed, like the stars, to be only absorbed by superior effulgence. The luminous spherical matter of the glow-worm is evidently enveloped in a sac or capsule perfectly diaphanous, which when ruptured discloses it in a liquid form, of the consistency of cream. M. Macaire, he observes, in the Bibliotheque Universelle, draws the following conclusions from experiments made on the luminous matter of this animal : that a certain degree of heat is necessary to their voluntary phosphorescence—that it is excited by a degree

of heat superior to the first, and inevitably destroyed by a higher—that bodies which coagri

late albumen take away the power—that phosphorescence cannot take place but in a gas containing no oxygen—that it is not excited by

common electricity, but is so by the Voltaic pile —and lastly, that the matter is chiefly composed of albumen. Genus 9. Mordella.—Antennae moniliform; thorar round; palpi four; when frightened it draws its head under the thorax; elytra narrower towards their point, slightly curved, and before the thighs is a plate at the base of the abdomen. M. aculeata is the most common of the British species, measuring from a quarter to half an inch in length: color entirely black; surface smooth: the abdomen compressed, and terminating in a sharp spine, extending beyond the wing-sheaths: the legs are rather long, and the insect, when disturbed, has the power of leaping or springing to a small distance. It is usually found on plants, in gardens and fields. It is observed to vary occasionally in color, having the wingsheaths sometimes marked by two transverse, cinereous, bars. Genus 10. Staphylinus.--Antennae moniliforma; feelers four; elytra half as long as the body: wings folded up under the elytra; tail not armed with a forceps, furnished with two exsertile vesicles. The insects of this genus are extremely rapacious, devouring not only the insects of other genera, but frequently each other. Many of them, when attempted to be caught, turn up the tail. The jaws are very strong, with which they bite and pinch very hard : most of them are found in damp moist places, and a few upon flowers. A well-known species is the black soldier, or S. murinus, the color of which is cinereous; abdomen and legs deep black. It is found in this country, among decayed carcases and dung. The shells are blue, and polished beneath. The larva is sixfooted, naked, and of a pale hue. The head and three first segments of the abdomen chestnutbrown; tail with two jointed bristles, and a cylindrical tubercle beneath. The great rove-beetle, S. olens, presents a striking and rather terrificappearance, when, with its large jaws expanded, and its abdomen turned over its head like a scorpion, it menaces its enemies, and thus preserves itself from numerous attacks.

Class III.-Antennae setaceous, or growing gradually thinner from base to point.

Genus 1. Cerambyr.--Antennae setaceous; palpi four; thorar either spinous or gibbous; wing-cases linear. This is a numerous genus, it has therefore been divided into several genera by later writers. The larvae mostly live in wood, which they perforate and consume, and are the favorite food of the woodpecker. The antennae of several of this genus are four times their length. In the larva state they are sometimes eaten; in the West Indies these larvae are collected by the negroes as an article of luxury for the tables of their owners, and are in great esteem. Many of these insects possess a powerful odoriferous smell, similar to that of the European species moschatus. A well-known British species is the C. moschatus. Color, shining green; antennae of a moderate size and blue; thorar spinous. This insect is found on the willow in European countries, and is generally known in England by the name of goatchaser, or musk-beetle, which last it merits particularly, the insect emitting a powerful smell of musk when alive. Length, including the antennae, about three inches. Genus 2. Leptura-Antennae setaceous; palpi four, filiform; wing-cases sloping off to a point; thorar somewhat cylindrical. Most of the leptura genus are furnished with legs of considerable length, and run with much speed and activity; they are found on flowers. A common British species is the L. aquatica, of a fine golden-green color, with the posterior thighs clavated and dentated; the antennae blackish, with a pale testaceous tint at the joints; head with a line down the middle; thorax grooved ; body beneath downy ; legs obscure, testaceous. Common in Britain, and other parts of Europe, on aquatic plants, particularly the nymphaea, Genus 3. Cantharis.--Antenna filiform; wingcases flexible; abdomen sides having 1. folds; thorar generally marginated. This is an extremely rapacious tribe, preying even on its own . § biguttata is a handsome insect, and is furnished with two red vesicles at the base of the abdomen, and two at the base of the thorax, which are raised or depressed alternately. It is common on various plants in the woods of Britain in the months of May and June. Genus 4. Elater.—Antenna filiform; feelers four, hatchet shaped; mandibles notched or bifid at their extremities. These animals having very short legs, when laid upon their backs, says Mr. Kirby, cannot, by their means, recover a prone position. To supply this seeming defect in their structure, Providence has furnished them with an instrument which, when they are so circumstanced, enables them to spring into the air and recover their standing. If you examine the breast (pectus) of one of these insects, you will observe between the base of the anterior pair of legs a short and rather blunt process, the point of which is towards the anus. Opposite to this point, and a little before the base of the intermediate legs, you will discover in the after breast (postpectus) a rather deep cavity, in which the point is often sheathed. This simple apparatus is all that the insect wants to effect the above purpose. When laid upon its back, in your hand if you please, it will first bend back, so as to form a very obtuse angle with each other, the head and trunk, and abdomen and metathorax, by which motion the mucro is quite liberated from its sheath; and then, bending them in a contrary direction, the mucro enters it again, and, the former attitude being briskly and suddenly resumed, the mucro flies out with a spring, and the insect rising, sometimes an inch or two, into the air, regains its legs, and moves off. The antennae are lodged in a cavity, scooped out of the under side of the head and thorax, to preserve them from injury when the insect falls after its singular leap. The larvae reside in decayed wood. ' The elater noctilucus, or fire-fly of St. Domingo, is a most remarkable creature. This insect, continues Mr. Kirby, which is an inch long, and about one-third of an inch broad, gives out its principal light from two transparent eye-like tubercles placed upon the thorax; but there are also two luminous patches concealed under the elytra, which are not visible except when the insect is flying, at which time it ap

pears adorned with four brilliant gems of the most beautiful golden-blue lustre: in fact, the whole body is full of light, which shines out between the abdominal segments when stretched. The light emitted by the two thoracic tubercles alone is so considerable, that the smallest print may be read by moving one of the insects along the lines; and in the West India islands, particularly in St. Domingo, where they are very common, the natives were formerly accustomed to employ these living lamps, which they called cucuy, instead of candles, in performing their evening household occupations. In travelling at night they used to tie one to each great toe; and, in fishing and hunting, required no other flambeau. And, according to P. Martire, “many wanton wilde fellowes' rub their faces with the flesh of a killed cucuius, as boys with us use o ‘with purpose to meet their neighours with a flaming countenance,’ and derive amusement from their fright. Genus 5. Cicindella-Antennae setaceous, palpi six, filiform ; the posterior ones hairy: mandibles projecting with many dents; eyes prominent; thorar rounded and marginated. These insects are alike noted for their beauty and rapacity, preying, with ravenous ferocity, on all smaller insects that fall in their way. The larva is soft and white, and commonly lurks in a hole, drawing in whatever prey may come near. Species C. campestris green, the elytra having five dots, white. Inhabiting sand-pits. ' Genus 6. Buprestis-Antenna serrated, and the length of the thorax; feelers four, filiform, with the last joint obtuse and truncated; head partly drawn under the thorax, Qí all the coleopterous genera there is none the species of which are so generally rich, resplendent, and beautiful, as those of buprestis; and these, in their first state, derive their nutriment from the produce of the forest, in which they sometimes remain for many years before they assume the perfect state, as if, says Mr. Kirby, nature required more time than usual to decorate these lovely insects. The principal species is B. gigantea, the grub of which is ascertained to have existed in the wood of a deal table more than twenty years. Genus 7. Dytiscus.--Antenna setaceous; palpi six, filiform; hind feet swimmers, with minute claws. The insects of this genus may be taken in ponds, ditches, &c., at every season of the year; they are therefore very numerous, and deserving of considerable attention. The larvae of most are furnished with anal appendages or swimmers, but some, not being possessed of such organs, never rise from the bottom. See our article Dytiscus. From this is derived the genus hydrophilus, which is thus described :-Antennae clavated; club perfoliate; hind feet formed for swimming, as the above dytiscus genus. The larvae of this genus are the crocodiles of the ponds, killing not only insects, but small dace, minnows, &c. The principal species is the hydrophilus piceus, the color of which is black, the sternum channelled and spiny. The only insects certainly known to spin an egg-pouch, like the spiders, are the hydrophili. That of the great water-beetle (hydrophilus ło was long ago described and figured by Lyonnet; and a more detailed account of it has since been given by M. Miger, which we extract from Messrs. Kirby and Spence. In form it somewhat resembles a turnip when reversed, since it consists of a pouch of the shape of an oblate spheroid, the great diameter of which is three-quarters of an inch; and the small half an inch, from which rises a curved horn, about an inch long and terminating in a point. The animal is furnished with a pair of anal spinners, which move from right to left, and up and down, with much quickness and agility: from these spinners a white and glutinous fluid appears to issue, that forms the pouch, which it takes the animal about three hours to construct. The exterior tissue is produced by a kind of liquid and glutinous paste, which, by desiccation, becomes a flexible covering, impermeable to water; the second, which envelopes the eggs, is a kind of light down of great whiteness, and keeps them from injuring each other. The tissue of the horn is of a silky nature, porous and shining, and greatly resembling the cocoons of lepidoptera. This part, contrary to what Lyonnet supposes, appears calculated to admit the air, the water soon penetrating it when submerged. At its base is the opening prepared for the egress of the larvae, when hatched, which is closed by some threads, that, by means of the air confined in the cocoon or pouch, hinder the water from getting in. This nidus does not float at liberty in the water till after the eggs are hatched, the parent animal always attaching it to some plant. By means of this anomalous

process for a beetle, which this insect is in

structed by providence thus to perfect, the precious contents of its little ark are secured from the action of the element which is to be the theatre of their first state of existence, from the voracity of fishes, or the more rapacious larvae of its own tribe, until the included eggs are hatched, and emerge from their curious cradle, The larva lives in still waters and ponds, its nead is smooth and of a dark brown color, with six feet placed on the back and a tapering tail. In the month of July it attains to its full size, and leaving the water creeps to a heap of dung, and buries itself in a deep hole underneath, lying coiled up in a circle, and thus changing to the chrysalis or pupa state. About the middle of August the perfect insect makes its appearance. Genus 8. Carabus-Antenna filform; palpi six last joints thick and truncated; thorar heartshaped, truncated at the point, and marginated; wing-cases marginated. Mr. Marsham has described 109 British species of this tribe, which are mostly found on the ground, or under stones, &c. The whole of this genus are very voracious, preying on all insects they can overcome; when

taken they discharge a brown, fetid, and caustic

liquor; many of them want wings, and their larvae reside in putrid wood, mosses, &c. One of the most destructive of this species is the C. sycophanta. The grub takes up its station in the nests of bombyx, and fills itself so full that it appears ready to burst. Another celebrated insect of this tribe is the bombardier, for an account of which, see CA> A to U's. Genus 9. Necydalis.--Antenna setaceous: **p, four, filiform; wing-cases smaller than the

wings. This genus is generally found in woods, in their perfect form; but the larvae are unknown. In some the thorax is black, in others yellow; the elytra are generally black, and lighter towards the middle, which often contains a yellow, or lemon-colored spot. Genus 10. Forficula-Antennae setaceous; feelers filiform, but unequal; wing-cases shortel than the abdomen and cut short off at their tips; abdomen armed with forceps. The well known earwig (forficula auricularis) belongs to this genus. The two sexes differ in the shape and bulk of the abdomen, as well as the forceps at the extremity of the abdomen. The female is distinguished by the superior size of the abdomen. The eggs are large, white, and glossy; and the larvae, when hatched, considerable in proportion to the magnitude of the egg from which they are excluded. Few of the insect tribe evince more attention to their young than the females of the forficulae. They are particularly careful to deposit their eggs in places of security, and are often seen sitting on them for hours together; and they are also known to regard the infant brood with tenderness, the young remaining in society with the parent some time after being produced from the egg.

ORDER II.-HEMIPTERA.

Most of the insects of this order are provided with a long beak or rostrum, bent inwards towards the chest; their wing-cases are soft, and cross each other with a portion of the anterior margins. Genus 1. Blatta.--Antenna setaceous, head bent inward, feelers unequal, wing-cases flat, wings flat and coriaceous, thorar flattish and margined, feet cursorious, tail having two horns on the top. The principal species is the B orientalis, originally a native of South America, but now too well known in Europe by the name of the cock-roach. It frequents, kitchens and all warm parts of a house, and devours all sorts of vegetable provisions. It generally conceals itself in the day time, and runs quickly if discovered, or a light is brought near them. See BLATIA. Genus 2. Gryllus.—Antenna filiform, headbent inward and having jaws; palpi filiform; wings four, deflected and rolled, under pair folded, hind feet saltatores, and all furnished with two claws. To this genus belongs the devouring locust, of which we have already treated in the introduction to this treatise, we shall therefore only give the following account of their ravages in Transylvania, Wallachia, Moldavia, Hungary, and Poland, in 1747 and 1748, from the sixty-fourth number of the Philosophical Transactions. “The first swarms entered into Transylvania in August, 1747: these were succeeded by others, which were so surprisingly numerous that, when they reached the Red Tower, they were full four hours in their passage over that place: and they fiew so close that they made a sort of noise in the air by the beating of their wings against one another. The width of the swarm was some hundreds of fathoms, and its height or density may be easily imagined to be more considerable, inasmuch as they hid the sun, and darkened the skv, even to that degree, when they flew low,

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