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common gnat, for example, deposits its eggs account being very accurate, we give it enin water, attaching them side by side, by tire. means of its long hind legs, in such a way as to form a perfect life-boat, which no rough treatment can upset or sink; it being doubt-gnat is transformed into a pupa, it prepares, gene

less essential for the welfare of the future progeny that the eggs should float on the surface of the water and not sink in it.

"About eight or ten days after the larva of a

rally towards noon, for emerging into the air, raising itself up to the surface so as to elevate its shoulders just above the level of the water. It has scarcely got into this position for an instant, when, The two next stages of the gnat's exis- by swelling the part of its body above water, the tence are passed in the water. Every one skin cracks between the two breathing tubes, and is well acquainted with the little active immediately the head of the gnat makes its apwriggling creatures, with large heads, which pearance through the rent. The shoulders instantly follow, enlarging the breach so as to render during the summer months abound in water, the extrication of the body comparatively easy. and especially rain water, when freely ex- The most important and indeed indispensable part posed to the air. These are the larvæ and of the mechanism, is the maintaining of its upright and pupæ* of gnats. The larvæ as soon as position, so as not to get wetted, which would they leave the floating egg, descend into the spoil its wings, and prevent it from flying. Its water, there to await the arrival of the period chief support is the rugosity of the envelope which it is throwing off, and which now serves it as a for assuming their winged aërial condition. life-boat, till it gets its wings set at liberty, and But although they thus exist in a different trimmed for flight. The body of the insect serves element, yet the respiration of atmospheric this little boat for a mast, which is raised in a air is absolutely necessary to their exis- manner similar to moveable masts in lighters contence; and the means of obtaining it are structed for passing under a bridge, with this dif accordingly provided in the shape of a curi- ference, that the gnat raises its body in an upright ous apparatus situated near the tail of the direction from the first. When the naturalist,' larva. The larva suspends itself from the says Réaumur, observes how deep the prow of surface of the water by means of the ex-ious for the fate of the little mariner, particularly the tiny boat dips into the water, he becomes anxtremity of this breathing tube, which is ca- if a breeze ripples the surface, for the least agitapable of being opened out into a stellate tion of the air will waft it rapidly along, since its form, and it thus, while used as an organ of body performs the duty of a sail as well as of a respiration, also acts as a buoy. When the mast; but as it bears a much greater proportion to little creature wishes to descend, it closes the little bark than the largest sail does to a ship, the hairs at the end of the tube; and on re-laid on its side all is over. it appears in great danger of being upset; and once I have sometimes seen ascending they are again opened. the surface of the water covered with the bodies

After two or three moultings, the larva of the gnat becomes a pupa; in this state food seems to be no longer necessary, but fresh air is indispensable to its existence, though still living in the water. Unlike that of the larva, the respiratory apparatus of the pupa consists of two tubes placed behind the head, instead of being situated in the tail, which in the pupa is fin-shaped, and appears by its motion to assist the animal in maintaining its position at the surface of the water. The next operation-that of assuming the perfect state-is a most interesting one, which we have witnessed with admiration many times. It is well described in Réaumur's "Insect Transformations ;" and this

·

of gnats which had perished in this way; but for
the most part all terminates favorably, and the
danger is instantly over? When the gnat has ex-
tricated itself all but the tail, it first stretches out
its two fore legs, and then the middle pair, bending
is able to walk as upon dry land, the only aquatic
them down to feel for the water, upon which it
faculty which it retains after having winged its
way above the element where it spent the first
stages of its existence."-Lib. Ent. Knowi. Ins.
Trans.,
p. 317.

The dragon-flies, or "horse-stingers," as they are erroneously called by the country people, also deposit their eggs in the water, where they are hatched; and the young, like those of the gnat, pass the two first stages of their life in that element. The larva is "We have four stages in the life of an insect-furnished with a very curious respiratory four states which it is necessary thoroughly to understand; the egg (ovum), which is motionless and apparatus, by which it is enabled to sustain apparently lifeless; the grub (larva), which is active, an intermittent pumping up and discharge but without wings, voracious, and grows rapidly; of water, thus serving at the same time both the chrysalis (pupa), which is quite motionless, and does not occur in all insects; the perfect insect (imago), which is active, has wings, does not grow, and which, by laying eggs, perpetuates its kind."Newman, 2.

as an organ of locomotion and of respiration. But this is not the only curious circumstance connected with this larva. The under lip of the mouth in the larva of most insects is

very small; but in that of the dragon-fly it is very large and of a most extraordinary structure, thus well described by Kirby and Spence.

"It is by far the largest organ of the mouth, which, when closed, it entirely conceals, and it not only retains but actually seizes the animal's prey, by means of a very singular pair of jaws with which it is furnished. Conceive your under lip (to have recourse, like Réaumur on another occa

These voracious larvæ do not, however, trust solely to this curious apparatus when seeking for prey, for they stealthily close upon it as a cat will do upon a bird or upon a mouse, and then suddenly unmasking seize it by surprise: insects, tadpoles, and even small fishes are thus captured.

Like the pupa of the gnat, that of the dragon-fly is under the necessity of seeking the air in order to assume its perfect winged condition, but its avoidance of water is much more complete than in the case of the gnat ; for not content with merely ascending to the surface, there to get rid of its now useless integument, the dragon-fly leaves the water entirely, generally by crawling up the stems of aquatic plants, upon which it fixes itself by means of its claws, and thus remains motionless for a time, as if to gain strength for the coming struggle. After a while, the envelope may be seen to burst open between the shoulders; through the aperture protrudes the head of the perfect fly, and this is quickly followed by its legs, the cases of which remain attached as before to the plant. Another period of rest now intervenes, the head and upper portion of the body being bent backwards, and gradually becoming dry and firm. The fly then firmly grasping the upper portion of its cast skin with its feet, gradually draws out the remainder of its body, and again rests immovably. During this state of inaction the wings expand, all the crumples, plaits, and folds incidental to the confined space previously occupied gradually disappear, and the whole wing becomes a beautiful smooth gauzy membrane, traversed by nerves, and nearly the length of the body, which has at the same time been gradually enlarging and lengthening, and the limbs acquiring their just size and proportions. Moreover, while the wings are thus drying and expanding, the insect is instinctively careful to prevent their coming in contact, while wet, with any part of the body, which would render them unfit for use, by arching the latter in such a way that the convexity is downwards. The whole of this curious process we have watched with admiration; and once had the pleasure of explaining it to a little intelligent country boy, who happened to pass the piece of water where it was going on, and put the question, "What be them 'ere things a-doin?"

sion, to such a comparison) to be horny instead of fleshy, and to be elongated perpendicularly downwards, so as to wrap over your chin, and to extend to its bottom, that this elongation is there expanded into a triangular convex plate, attached to it by a joint, so as to bend upwards again and fold over the face as high as the nose, concealing not only the chin and the first-mentioned elongation, but the mouth and part of the cheeks; conceive, moreover, that to the end of this last mentioned plate are fixed two other convex ones, so broad as to cover the whole nose and temples,-that these can open at pleasure transversely, like a pair of jaws, so as to expose the nose and mouth, and that their inner edges where they meet are cut into numerous sharp teeth, or spines, or armed with one or more long sharp claws;-you will then have as accurate an idea as my powers of description can give of the strange conformation of the under lip in the larva of Libellulina, which conceals the mouth and face precisely as I have supposed a similar construction of your lip would do yours. You will, probably, admit that your own visage would present an appearance not very engaging while concealed by such a mask; but it would strike still more awe into the spectators, were they to see you first open the two upper jaw. plates, which would project from each temple like the blinders of a horse; and next, having by means of the joint at the chin, let down the whole apparatus, and uncovered your face, employ them in seizing any food that presented itself, and convey ing it to your mouth. Yet this procedure is that adopted by the larva of the dragon-fly provided with this strange organ. While it is at rest, it applies close to and covers the face. When the insects would make use of it, they unfold it like an arm, catch the prey at which they aim by means of the mandibuli-form plates, and then partly refold it so as to hold the prey to the mouth in a convenient position for the operation of the two pair of jaws with which they are provided. Réaumur once found one of them thus holding and devouring a large tadpole; a sufficient proof that Swammerdam was greatly deceived in imagining earth to be the food of animals so tremendously armed and fitted for carnivorous purposes. In the larvæ of Libellula, Fabr., it is so exactly resembling a mask, that if entomologists ever went to masquerades, they could not more effectually rehieve the insipidity of such amusements, and attract the attention of the demoiselles, than by ap-quoted from the "Zoologist" an exceedingly pearing at the supper table with a mask of this interesting account of the final transformaconstrution, and serving themselves by its assist- tion of a small species of Ephemera, or dayance."-Inuod. in. 126. Iny, illustrative of what MI. Newman well

In a former number of this "Review" we

calls"the strange fact of an insect's flying before it reaches the imago; that is, flying in its penultimate state." The eggs of these flies are laid in the water, like those of the dragon-flies, which belong to the same class (Neuroptera), and the gnats. The larvæ live in the water two and even three years; when the imago is about to cast off its pupaskin, it leaves the water, and proceeds in the manner described in the quotation above referred to. The duration of the perfect insect's life is at most a few hours.

perfect form. Yet are there many insects whose lives are passed under similarly opposite conditions; and still more numerous are those whose progress from birth to muturity is characterized by changes of structure equally curious, which, however, are not so strikingly marked in consequence of their occurring in situations and under circumstances less opposed than those we have been considering.

Every resident in the country is well acquainted with the common cockchafer, or May-bug, but few, perhaps, are aware that the form in which they are most familiar with it-that of a large beetle-is the ultimate one of four several stages of insect life. Four years before the May-bug makes its presence unpleasantly known to us by dashing in our faces during our rural walks on the delicious evenings we sometimes have in May, it was carefully deposited in some field or meadow, in the form of an egg, in com

The Phryganeæ, or caddis-flies, also deposit their eggs in the water. The larva construct for themselves little habitations of small shells (which sometimes contain their living tenants), grains of sand, small stones, bits of stick, and other similar substances, made to adhere by the prototype of marine glue. These larvæ cannot swim, but being furnished with six legs, they walk with facility at the bottom of the water and being themselves heavier than water, it is neces-pany with perhaps hundreds of similar eggs, sary that their habitations should have a by a May-bug like itself. The parent, havspecific gravity so nearly corresponding with ing performed this duty, would soon cease to that of the water, that the animals may move exist; and towards autumn the eggs would about without being floated to the surface give birth to numerous minute whitish grubs. on the one hand, or compelled to remain at Between this period of hatching and the the bottom on the other. The larvae, there-third autumn, the grubs increase greatly in fore,evince their instinct-promptedknowledge size, and cast their skins three or four times, of hydrostatics, by attaching to their cells a piece of straw, or some other light substance, if too heavy; or too light, a shell or a piece of gravel. They never quit their habitations until about to assume the perfect form; when about to become pupa, the larva withdraw within their cases, after fixing them to some solid substance, and close each extremity with a grating which readily permits the passage of water through the case, this being necessary for respiration. The pupa makes its way out by means of a pair of hooked jaws, and swims about until it leaves the water for the purpose of under-ture to quit their subterranean asylum until going its final ecdysis; some of them climb up aquatic plants, like the pupa of dragonflies; others simply float up to the surface, as the pupa of the gnats do.

cach time burrowing deeper than their usual feeding level, as they likewise do in the winter, when they become torpid. In the third autumn after they are hatched the grubs prepare for assuming the pupa state, by burrowing to the depth of about a yard; and in a little chamber at the bottom of the burrows they remain inactive until the following January or February, when the perfect beetles emerge from the last covering they are to cast off; but for ten or twelve days they remain quite as soft as when in their first stage of existence, and do not ven

May, when they may be seen crawling out of the ground in great numbers, and soon taking flight. In the perfect state these insects live upon the leaves of trees; but the voracious It is very difficult, without actually wit- grubs devour the roots of grasses, sometimes nessing the successive stages of the lives of destroying whole acres of the finest pasture, such insects, to realize the curious fact, that and, as Kirby and Spence well observe, they the little merry dancing gnats, whose aerial" undermine the richest meadows, and so gambols all have observed; and the quick-loosen the turf, that it will roll up as if cut darting dragon-flies, with their iridescent with a turfing spade." Records have from glistening wings; and the gay Ephemera, time to time appeared of the extensive ravwhose aerial life is to terminate in a few ages of these grubs, which do not confine hours from the period of their assnming it; themselves to grass, but also eat the roots of were once the inhabitants of an element corn. The rooks are their most determined which would be fatal to them in their now enemies; for they not only follow the plough VOL. XV. No. IV.

30

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on woollen clothes which are not washed, the

for the purpose of devouring the grubs of it is of a black color, and so fœtid, that the hands the cockchafer, which, among others, are smell for hours after handling it; and if it crawl sometimes turned up in the furrows in great smell continues for several days. The sextonnumbers, but they instinctively, as it were, beetle lays its eggs in the bodies of putrefying dead pitch upon those meadows and portions of animals, which, when practicable, it buries in the meadows where the grubs are pursuing their ground. In Russia, where the poor people are subterranean work of destruction, root up buried but a few inches below the surface of the the grasses with their strong beaks, and feast ground, the sexton-beetles avail themselves of the luxuriously upon the rich repast thus laid bodies for this purpose, and the graves are pierced bare; as if to revenge themselves with their holes in every direction; at evening, upon the cause of the charge undeservedly brought church-yards, either buzzing over recent graves, hundreds of these beetles may be seen in the against them, of doing an injury to the farmer or emerging from them. The sexton-beetle, in by uprooting his grass, when, in reality, they this country, seldom finds so convenient a proviare conferring upon him one of the greatest sion for him, and he is under the necessity of benefits, by destroying an insidious enemy. taking much more trouble; he sometimes avails The very extensive class Coleoptera, or himself of dead dogs and horses, but these are too the beetle tribe, to which the cockchafer great rarities to be his constant resort; the usual belongs, furnishes many other examples of frogs, and moles; of these, a bird is most comobjects of his search are dead mice, rats, birds, insects exceedingly injurious to agriculture, monly obtained. In the neighborhood of towns, both in the larva and perfect states. Such every kind of garbage that is thrown out attracts are the different kinds of weevil which at- these beetles as soon as it begins to smell; and it tack grain, both while growing and when is not unusual to see them settling in our streets, stored away in the granary; the turnip-fly; enticed by the grateful odor of such substances. the wire-worm, which is the grub of one of The sexton-beetles hunt in couples, male and fethe little slender beetles allied to the exotic animal, they are almost sure to be males and female; and where six or eight are found in a large fire-flies; and many others, an attentive males in equal numbers; they hunt by scent only, study of whose habits in their various stages the chase being mostly performed when no other would probably suggest remedies for the in- sense would be very available, viz., in the night. juries inflicted by them. On the other When they have found a bird, great comfort is exhand, the same class furnishes examples of pressed by the male, who wheels round and round insects conferring benefits upon man, either above it, like a vulture over the putrefying carcass by preying upon other insects whose ravages it at once, without this testimonial of satisfaction, of some giant of the forest. The female settles on interfere with his comforts or with the sup- The male at last settles also, and a savory and plying of his necessities, or by removing ample meal is made before the great work is bedecaying substances which would otherwise gun. After the beetles have appeased the calls of become offensive to the senses. Of the for- hunger, the bird is abandoned for a while; they mer description are the larvæ of the lady- both leave it to explore the earth in the neighborbirds, which do good service by destroying able for interment; if on a ploughed field there is hood, and ascertain whether there is a place suitthe Aphides infesting the hop; of the latter, no difficulty; but if on grass, or among stones, in a small way, is the sexton, or burying much labor is required to draw it to a more suitbeetle, which actually consigns to the bosom able place. The operation of burying is performed of mother earth the body of any small ani- almost entirely by the male beetle, the female mal it may meet with; not, however, with a mostly hiding herself in the body of the bird about view of conferring a benefit upon the "lord to be buried, or sitting quietly upon it, and allowof creation," but in order that its own pro- by digging a furrow all round the bird, at the dising herself to be buried with it: the male begins geny may be provided with a fitting nidus, tance of about half an inch, turning the earth outand that they may find a sufficient store of side; his head is the only tool used in this operaprovision on emerging from the egg. An tion; it is held sloping outwards, and is exceedexceedingly pleasing description of the pro-ingly powerful. After the first furrow is comceedings of this beetle and his mate, from pleted another is made within it, and the earth is the pen of an observer who, we regret, now thrown into the first furrow; then a third furrow writes no more, appeared some years ago in is made, and this is completely under the bird, so that the beetle, whilst working at it, is out of sight: the " Entomological Magazine," with the now, the operation can only be traced by the heavsignature of "Rusticus, of Godalming," and ing of the earth, which soon forms a little rampart is quoted by Mr. Newman in his "Intro-round the bird; as the earth is moved from beneath, duction to the History of Insects," from which we here extract it.

and the surrounding rampart increases in height, the bird sinks. After incessant labor for about three hours, the beetle emerges, crawls upon the "The sexton-beetle is about an inch in length; bird, and takes a survey of his work. If the fe

it above ground than below. But if they had left thus exposed the carcass in which their eggs were deposited, both would have been exposed to the imminent risk of being destroyed at a mouthful by the first fox or kite that chanced to espy them."Introd. i. 354.

male is on the bird, she is driven away by the male, who does not choose to be intruded upon during the important business. The male beetle then remains for about an hour perfectly still, and does not stir hand nor foot; he then dismounts, dives again into the grave, and pulls the bird down by the feathers for half an hour; its own weight appears to sink it but very little. At last, after two or three hours' more labor, the beetle comes of the timber-boring insects, among which Much as we may deplore the devastations up, again gets on the bird, and again takes a sur-the beetle tribe figures most conspicuously, vey, and then drops down as though dead, or fal- it must be remembered that in pursuing their len suddenly fast asleep. When sufficiently rested he rouses himself, treads the bird firmly into its grave, pulls it by the feathers this way and that way, and having settled it to his mind, begins to shovel in the earth; this is done in a very short time, by means of his broad head. He goes behind the rampart of earth, and pushes it into the grave with amazing strength and dexterity: the head being bent directly downwards at first, and then the nose elevated with a kind of jerk, which sends the earth forwards. After the grave is thus filled up, the earth is trodden in, and undergoes another keen scrutiny all round, the bird being completely hidden; the beetle then makes a hole in the still loose earth, and having buried the bird and his own bride, next buries himself.

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The female having laid her eggs in the carcass of the bird, in number proportioned to its size, and the pair having eaten as much of the savory viand as they please, they make their way out, and fly away. The eggs are hatched in two days, and produce fat scaly grubs, which run about with great activity; these grubs grow excessively fast, and very soon consume all that their parents had left. As soon as they are full grown they cease eating, and burrowing further in the earth become pupa. The length of time they remain in this state appears uncertain; but when arrived at the perfect state, they make round holes in the ground, from which they come forth."-Newman, p. 53.

Of the unwearying industry shown by these beetles, some idea may be formed by the result of experiments conducted by M. Gleditsch, as quoted by Kirby and Spence, from an interesting article in the "Acts of the Berlin Society" for 1752. M. Gleditsch found that "in fifty days four beetles had interred in the very small space of earth allotted to them, twelve carcasses: viz., four frogs, three small birds, two fishes, one mole, and two grasshoppers, besides the entrails of a fish, and two morsels of the lungs of an

OX.

In another experiment a single beetle buried a mole forty times its own bulk and weight in two days." To this account the authors add the following pertinent remarks:

"It is plain that all this labor is incurred for the sake of placing in security the future young of these industrious insects along with a necessary provision of food. One mole would have sufficed a long time for the repast of the beetles themselves, and they could have more conveniently fed upon

destructive operations they are but performing their share of the general economy of nature, which provides for the removal of all organic substances, whether animal or vegetable, as soon as the vital principle has ceased to actuate them. That all such substances shall return to the dust whence they sprang is a decree from which there is no appeal; and the insect tribes do but hasten its fulfilment, while engaged in destroying our books, our furniture, the wooden framework of our houses, or the lofty tenants of our forests. The ease with which wood, when much " worm-eaten," is crumbled, even between the fingers, is well known; but it may not be so generally understood that the "worms" which produce this effect upon articles of furniture formed of wood, are no other than the soft-bodied grubs of various coleopterous insects, which are thus carrying out on a small scale the more extensive operations that quickly reduce to a similar condition the giants of tropical forests. Our domestic pests of this description are chiefly small beetles, which pass the early part of their lives in the wood, through it in all directions, only emerging and by means of their powerful jaws mine when they assume the perfect state. of these is the "death-watch," which even yet is an object of superstitious dread to the inhabitants of many an old house, of the wood-work of which it has taken posses

sion

One

weak minds, and which is often considered The ticking noise, so alarming to some member of the family, is merely the an infallible presage of impending death to call note of the perfect beetle of several bium, and, as we have often observed, species chiefly belonging to the genus Anoprincipally by the largest species, A. tesse

latum.

noise, which greatly resembles the ticking The manner of producing this of a watch, is thus very accurately described by Kirby and Spence.

"Raising itself upon its hind legs, with the body somewhat inclined, it beats its head with grea force and agility upon the plane of position; and

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