The May-fly As has already been mentioned, it has phase of existence. and as it cannot eat, is evidently incapable of any no mouth, term of Hfe. It has in fact but one business, lengthened a mate, and provide a new generation in place namely, to seek is now passing away. The May-fly seldom lives of that which than a few hours, and in its natural condition is supposed more exceed the limits of a single day. The name Ephemnever to is formed from two Greek words signifying an era, which to this shortness of life, and was

existence of a day, alludes as long ago as the time of Aristotle.

Piven to the insect lived longer than this bne

Isolated specimens have certainly to live more than a week in

term, for they have been knmvn been at liberty, it is most procaptivity. Had they, however, lives would have been as short bable, if not certain, that their

as is mostly the case with the May-flies.

In Kirby and Spence’s well-known work, there is an account

of a still more strange prolongation of life. There are certain flies whose larvffi feed on aphides, which live in their three stages about six weeks. One of them had been caught when half-giown, and, having been once or twice fed, was forgotten for three months, when it was found to be alive. It actually lived for a whole year without a particle of food, and, as is well remarked, ‘ it had existed in the larva state more than eight times as long as it would have lived in all its states, if it had regularly undergone its metamorphoses, which is as extraordinary a prolongation of life as if a man were to live 560 years.’

Sometimes the May-flies are wonderfully numerous, the air being filled with their swarms as they flutter up and do-wn in their strange flight, and the trees and banks covered with the shed pellicles of the first-winged stage. Even in England I have known the May-flies to be in such swarms that the very trout could not be taken with the hook, so gorged were t ey with the May-flies that fell by thousands into the water. In some parts of Europe, however, the numbers of these insects are so vast, that their bodies for manuring the are collected into heaps and used fields.

^ conspicuous one, and there is no likelihood of mistaking one of them for any other kind of nsect. Scientifically these insects are termed Libellulidie, and

ey are fanuliarly known as Dragon-flies or Horse-stingers, the h ter name being gxven them from an absurd notion sting tfat Ihey

horses. It is curious to notice how widely and deeply people, and to see how terrified they are at the verv idea of ouching a I)^gon-%. I suppose that the of the convulsive ^erkino-s long-bodied Dragon-flies when captured have Xn Z to this opinion. With regard to the name of IS a very Dragon-flTes it appropriate one, as we shall In these insects the presently see. body is always lone- and in tv, +

neary clerical, some^it “de

g y veined, and of equal size ; and the meshes or ‘ rptiVnio , - - c,o.e aa to divide the wing iato a

The head is adorned with two enormous eyes, or rather eyemasses, and, during the life of the insect, the light plays in and through these eyes in a most beautiful but quite indescribable manner. Unfortunately, this play of colour and light fades together with the life, and, when the insect is dry, Beside the compound eyes, there are • it vanishes altogether. three ‘ ocelli,’ or simple eyes, placed usually in a row on the front of the head. The antennae are very short and small, and have never more than eight joints. The mouth is very formed, the mandibles and the maxillae being hidden curiously two large flat lips, which move up and down while the behind insect is eating, so that at first sight the Dragon-fly really looks as if its mouth worked vertically and not laterally. stages the Dragon-fly lives in the

During its preliminary and the larva is one of the most curious and interesting water, produce. These larvae are so wonderful, beings which our waters so many points of interest, that I scarcely in fact, and possess to take first. The chief points of interest lie, know which and the tail, and we will give to the however, in the head former the place of honour. sight the head does not appear to differ very much

At first of other insects, but on closer examination a very from that of the mouth is shown. If the creature singular development on its back, a horny plate will be seen, which covers be turned under side of the head and descends as far as the whole of the pair of legs. With a pm it is easy the bases of the middle then shows itself to be composed of to raise this plate, which furnished with a hinge, by means of several portions and upon itself. The upper part, which which it can be doubled widened, and is furnished with two covers the face, is much can be opened or closed at will, jaw-like appendages, which finely toothed at their lower edges. and are is a development of the lower hp,

This remarkable apparatus when closed, it covers the and is called the mask, because, object of the mask is to catch

lower part of the head. The it is. When an unforprey, and a very effective apparatus Dragon-fly larva suddenly un-

Late insect comes near, the it out to its full lengtli, and seizes th folds its mask, darts mask is then closed again and, whe

insect in the jaws. The come exactly upon those of

folded, the jaws of the mask

mouth, so that the prey can be eaten without trouble. In

Plate VIII. Fig. 4, the end of the still folded mask is seen, the jaws being opened preparatory to the darting forward of the

mask. The shape and details of this structure vary somewhat in the diflFerent species.

The larva is a voracious creature, and will eat almost any aquatic insect which it can master, and has even been known to catch and eat small fishes. In its own tui-n, however, it falls a victim to the more powerful inhabitants of the water, being attacked and eaten by the Dyticus and even by the Acilius. Two specimens of Acilius which I kept in an aquarium managed to eat, in little more than a fortnight, three out of fom- Dragon-fly larvas which were in the same vessel ; and in the waters where the creatures live I have often found the dead and partly-eaten bodies of Dragon-fly larv®, the destroyer having evidently been the Dyticus.

We will now proceed to the other end of the creature, and examine its tail. When taken out of the water, the tail apears to end in a sharp, horny point ; but, when it is replaced in water, the pointed tail opens and shows that it is composed ot five sharp appendages, three being much larger than the others. When they are opened, a tube is discovered passing into the body of the larva. All the five spikes are jointed together at their bases, so that if one be drawn aside the other four immediately spread themselves apart. The aperture which lies between them is just large enough to allow an ordinary pm to pass easily through it. ^

Within the abdomen is the respiratory apparatus, which extracts the o.jgen from the water, and, when that gi has been exhausted the water is expelled and a fresh supply through the same taken in aperture. If the larva be placed in a vessel and watched carefully, the process "of be easily observed. The five pointed projections are kept about If open, and the water is ejected in gentle and tolerablv Should it, however, be alarmed, it suddenly exnels thA ^ + with »uch violence that it drives itself speed, the principle being exactly the same as that causes the flight of a ‘ rrioM rocket. If the bottom of the vessel in which the larva is kept be

of the expelled water can he at dusted with fine sand, the force of the sand. If the vessel once measured by the displacement such proof of the propelling power can be be a deep one, no the water as if impel ed seen and the creatui-e darts through The reader may perhaps remember by some magic power. has lately been applied to that a ‘ direct action ’ movement having been avowedly borrowed from steamboats, the principle this very creature. . , i-u in form or habits between the

There is very little change the end of the larval existence, larva and the pupa. Towards its appeara^uce on the upper a sort of longitudinal hump makes last larval skin is thrown off, part of the thorax, and, when the wings, which are at is seen to consist of the future this hump small, their tips only reaching about present thick, narrow and abdomen. The mask reta^ins

quarter of the length of the Ine the head is much larger and broader, its place and office, hut insect begin to shine eyes of the perfect a^ the splendid in the pupal as in the larval stage of "quLTvtfmous just seized with its One of my own specimens has existeuce. which had been unlucky mask the larva of a Whirlwig Beetle whole proceeding was very ■U i- o -mUhiTi reach The insects. The rn.sk oTlhe toad when catching mS Iffie rt so rapidly that its movements flashed out larva had been graspM and in a moment the unfortunate hy the middle and held against^the ™eUa«^ S^japi^ darted into its destroyer's if tte rva‘fad“ftStoally mistake. It saw insects made a rather absurd

“one’ of these on the suiface, a detached leg o a Dyticus y which -i. was aoWpd floating the lesf in passing,

f f lipd leo- of

shot itself immediately under to eft

w-ke sir^mran

stfe rk!r;rbfi: ™ also given n,ad of voracffiy

"a i«ir“rlgefproof

itself a voracious and formidable creature, being furnished with two enormous curved jaws, and in form almost exactly resembling the larva of the Dyticus shown on Plate III. Fig. 4. Thinking that the larva would be very well able to take care of itself, I put it into the basin, intending next morning to observe through the microscope the fringed apparatus at the 27 3‘ end of the body. But, at a very early hour next morning, the larva had vanished. I knew that it was physically incapable of crawling out of the vessel, and at last, after a strict search, I found one of its large mandibles lying at the bottom of the basin, the only vestige that the voracious Dragon-fly larva had left of its victim.

Since that enormous meal the larva has changed into a pupa, and is just as restless and voracious, and has completed its course of destruction by killing and eating its companion, the contents of whose body it has completely scooped out.

Although neither in the larval nor pupal state does it possess the vivid colours with which the perfect insect is adorned, it is yet possessed of a certain beauty. The colour of the body is pale brown, but the legs are as translucent as if made of horn and handed at regular intervals with small dark-brown stripes. Along the sides, each segment of the body is furnished with two sharp and projecting spikes, which point towards the tail. In consequence of this structui-e, the creature is a difficult one to hold, wriggling itself like a snake when held in the fingers, and gradually working its way through them. The best way of examining these curious beings is to take one of them and place it in a shallow saucer, with just enough water to cover it. The under sm-face can be observed m the same vessel ; for, if the larva be laid on its back, it gives a^ few struggles and then seems to acquiesce in its position, lying perfectly still, and allowing the lens to be placed close to its body without alarmed. appearing to be in the least

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