There are many species of these insects, which popularly go the collective name of Thrips, but the distinctions are under and minute for any but a purely scientific work. too many position of the order is still a mooted point among The exact as these insects resemble the Orthoptera and entomologists, while the structure of the Hemiptera in their transformations, unlike that of either of these orders. Van der mouth is quite scarcely to think that the Thysanoptera con- Hoeven seems and considers them as an appendix to stitute a separate order, the Orthoptera.

Neijeopteea.

Neuboptbea.

CHAPTER I.

The important order of insects which comes next on our list is a very remarkable one. The name Heuroptera is formed from two Grreek words, the one signifying a nerve, and the other a wing, and has been given to these insects because the transparent wings are traversed by a vast quantity of nervures, which^ divide the wings into a greater number of spaces or ‘ cells ’ than is the case with any other order of insects. Both pairs of wings are of equal size and of equal solidity. The larva has always six legs, and the pupa is and sometimes active. sometimes quiescent

The Heuropterous insects fall naturally into several groups the characteristics of which are so strongly marked that they are well known by popular names, such as Stone-flies, Dragonflies, Lace-wing-flies, and the Hke. There are not inanv species inhabiting England, but the insects are mostly plentiful and are sufficiently large and tne handsome to constitute much of

beauty of our country scenes.

We will begin mtt the Perlidae, or Stone-flies, as they are popularly called. These insects are very dear to the angler nmsmuch m they supply some of his best and most certain baits’ whether the real insect be used, or only the imitation called dull “ore valuable from being dull and slupsh in their habits, so that they can be easilv captmed as they sit upon the trunks, stones, and other obS near the water’s edge.

cut° ■ may is shown in Woodbe at once recognised Thp colour of this insect is pale yellowish brown, andThe n'ervmes

of the Upper wings are peculiarly large and bold. All the Perlidae have the second pair of wings, very large, and capable of being folded. The body is rather flattened, and equally wide throughout its length. The tarsi have three joints.

These insects are aquatic in their habits. During their larval and pupal stages they live in the water, and after they

Perla marginata. 2 Liinnephilua Labium of ditto, o. LimnepMlus, labium. b. Limnephilus, maxiua. ochraoeuB male. e. Anal appendages or clasper, male. female. d. Labium, they love to remain neai have attained their perfect condition, and seldom trave o any the water in which they were reared, The mother insect imitates distance from the famiUar hanks. for she carries the e^. in one respect the female Cockroach, to the end of the abdomen, for soni about with her, attached however, e>ic » ed n they are laid. They are no^ time before b t am like those of the Cockroach, a hard case or pouch, black g o u ai » together in a small merely united

the eflfect of which against the light-brown grey body and wings is very remarkable, as the insect flutters heavily from spot to spot. The membranous envelope within which the eggs are contained is exceedingly delicate, so that it shows both the shape and colour of the eggs which it encloses. The egg-cluster of Perla marginata is about as large as a swanshot, and nearly as black. It is rather more barrel-shaped than globular, and, on being examined with a lens, is seen to be composed of several hundred eggs, agglutinated together in a sort of semi-order, as if the eggs had been deposited in strings, and the strings wound at random into a ball.

These eggs are deposited in the water, and when hatched, the young larvae manage to crawl under stones and similar sheltered localities. They prefer running to still waters, and the more rapid parts of the stream to those which are comparatively still. In the swift river Dove these creatures are very plentiful, and I used to capture almost any number of them in the spring time, the rippling, eddying stream exactly suiting them. Near my present house is a very small pond, through which a stream of water continually runs. It is marvellously rich in insect life, and I have captured in it a variety of aquatic insects in all stages, which utterly astonish those who are not initiated in the wealth of entomology. Yet, though I have industriously fished every inch of this pond, I have never found the larva of the Stone-fly. Larvae of Mayflies, Dragon-flies, Caddis-flies, Dyticus, Acilius, Gryrinus, Notoesta. Gnats, and other aquatic creatures, I take in plenty, but not one single Stone-fly larva have I found, though I have sedulously examined both the inlet and outlet of the stream which mns through the pond and keeps it suppKed with water.

In the present genus, the abdomen is very stout, and has two long slender appendages at its tip. The wings of the male are very short in proportion, and altogether he is quite an inferior being to his stately mate. There are several species of this group in England, some of which are known to ano-lers bv various popular names. The name of Stone-fly is, however given indiscriminately to at least four species. One is that which has already been mentioned ; another is scientifically kno^vn Perla grandd-s; a third is Perla eephalotes, which, as Its name implies, has a very large head ; and a fourth, perhaps

the best known, is Perla bicaudafa. Then, the familiar ‘ Yellow Sally ’ of anglers is Chloroperla vindis, and the equally familiar ‘Willow-fly’ belongs to the genus Nemoura.

As is the case with many other aquatic insects, the pupae of the Stone-flies crawl out of the water when they are about to assume their perfect state, so that when they come to expand their wings an ample space may be gained for this important, and often perilous, task. The details of this process will be explained in connexion with the various species of Neuropterous insects.

All the Perlidae have a very moth-like aspect, especially on the wing, and, owing to the invariable sombreness of their hues, and their great similitude in shape, there is considerable difficulty in distinguishing between the various species. With many species this difficulty is still more increased by the difference in size between the sexes, the males being scarcely one-third as large as the females, and having wings very short in proportion to the length of their bodies.

Now we come to another family, the Ephemeridse, better known by the popular name of May-flies. In many respects these are veiy curious insects, and not the least remarkable point about them is that in the perfect state they have no mouth. The parts of the mouth are certainly there, but in a rudimentary condition, and entirely incapable of receiving food, so that during the time of its existence as a perfect Ephemera never eats, neither does it require to eat. insect, the

The wings are very unequal in size, the lower pair being very small, and in some species reduced to mere rudiments. In of this formation of the wings, Di. Leach conconsequence sidered that the May-flies ought to be formed into a sepai-ate order, to which he gave the name of Anisoptera, or unequalwinged insects. The end of the body is fuimished with either and slender filaments ; and by these three two or three long — the mouth, the wings, and the tail— the May-flies characters from all other insects. The best may be at once distinguished vulgata, or Common Mat-fly, is known species. Ephemera shown on Plate VIII. Fig. 1. of the May-flies are very remarkable,

The transformations almost unique. In its larval condition, and in some respects

Plate Viii. Dragon-Flies, Mayflies, And Caddis.

Ephemera vulgata. 2. Ephemera, larva. 3. Libellula depressa. Sa.Libellula emerging from pupa-case. 4. Libellula, larva.
Agrion minium. 7. Phryganea grandis. 8. Phryganea, larva cases, or Caddis, Plants ; — eryx Flowering Push {Butomus mnbellatus). In Centre. virgo. Mare’s-taU {Hippuris vulgaris). On Right. Water Bistort {Polygonum amphibium). On Left.

I 1 7

I resembles the perfect insect, except that it has no wings. the May-fly is an inhabitant of the water, and in form much

This species lives in the muddy banks of rivers and ponds, and r: biuTows for itself certain ingenious tunnels. These burrows are double, running horizontally into the mud, and having two outlets. In fact, they are shaped much like the letter C, so that the larva can crawl in and out of its hole with perfect ease. Its food appears to consist of the decaying vegetable matter of which fresh-water mud is largely composed.

In consequence of its hidden dwelling, this larva is not often 4 seen even by those who are in the habit of fishing for aquatic insects. I have found two plans to be successful in its capture. The first is, to detach a large piece of mud, take it carefully from its place, and then examine it under water. The second plan is, to push a stick into the mud and work it about so as to drive the larvse out of their burrows, and then to move the net rapidly to and fro in the clouded water. By this plan several other aquatic insects may be captured, which are much too wary to allow a net to come near them as long as they can see it. The muddy water, however, reduces them to a temporary state of blindness, and they are then taken without difficulty. Some of the smaller species do not burrow, but live at liberty in the water. In these species the surface of the body is harder than in those which burrow.

One of these larvae is shown in Plate VIII. Fig. 2, in order to give the reader an idea of its shape. In its larval condition this creature is furnished with two rather long and manyjointed antennae, which, in the perfect insect, shrink into an almost rudimentary form. Along each side of the body runs a senes of thin plates in whicli the branchiae or gills spread themselves. These are said to assist in locomotion, but I have not seen them used for that purpose ; the undulation of the body and the employment of the legs seeming to be sufficient for that purpose. At the end of the abdomen are three friuo-ed appendages or seto3, and it is a rather curious fact that even in those species which have only two setae in the perfect state the larva possesses three of those appendages. The pupa differs little in shape from the larva, except that the wings show themselves t<uor<ix* boldly m the form of projections in the back of the

After passing some two years in the preliminary stages, the Ephemera prepares for its change into the perfect form. Tlie pupa leaves the water, and almost as soon as it emerges into the open air, the pupal skin splits, and enables the insect to crawl from within its former envelope. The wings are soon stretched to their utmost, and the insect then flies slowly to some tree or post where it affixes itself, and appears to rest after its exertions.

Another change, however, awaits the insect, for this state is

preliminary, and is scientifically called by the name of only ‘ pseudimago,’ or false insect. After it has waited for some little time — depending, as far as I can see, on the warmth and dryness of the atmosphere — the skin again splits, and thiough the aperture the insect emerges, leaving the abandoned skin clinging to the tree, and looking exactly like the living insect. The wings now assume a lighter and more delicate aspect, the filaments at the end of the body increase to nearly twice their and the May-fly launches into the air to take former length, evening dance with which we are all so familiar, its part in that rising and tailing almost in the same place for several the insects Should the reader be an angler, he will hours together. female pseudimago the ‘ Green Drake,’ and in recognise in the the perfect insect the ‘ Grey Drake.’ The angler only cares female insects, because the fish prefer them, laden as they for the males, which have little in them but air. are with eggs, to the has not much time in which to enjoy its new

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