The Insect World: Being a Popular Account of the Orders of Insects

NEUROPTERA,

and an arm; it seizes the prey on its passage, and conveys it to the mouth. " When any aquatic insect approaches them at a time when they are in a humour for eating," says Charles de Geer, " they shoot the mask forward very suddenly and like a flash of Hghtning, and 421 seize the insect between their two pincers; then, drawing back the mask, they bring the prey up to their mandibles, and begin to eat it. I have remarked that they do not spare those of their own kind, but

Fig. 394. — Larva of the Libellula, and the perfect insect emerging.

that they eat each other up when they can, and I have also seen them devouring very small fish which I put by them. It is very difticult for other insects to avoid their blows, because, walking along generally in the water very gently, and, as it were, with measured steps — almost in the same way a cat does on the look-out for birds — they suddenly dart forward their mask and seize their prey instantaneously."*

Fig. 394 represents, to the left, the larva of the dragon-fly, with the

• Charles de Geer, Memoires pour servir a I'Histoire des Insectes," tome ii., 2e partie, p. 674.

instrument of attack which we have called a " mask," and which it is making use of for seizing a small insect; on the right, the adult dragon-fly coming out of the nymph.

The respiration of these larvae is very singular. Their abdomen is terminated by appendages, which they open to allow the water to penetrate into the digestive tube, the sides of which are furnished with gills communicating with the tracheae. The water, deprived of oxygen, is then thrown out, and the larva advances thus in the water by the recoil. It has no tufts of external lateral gills, which in the case of

Fig- 395 — LibcHula depressa, the Common Dragon-Fly.

the Ephemerce do the duty of fins. The pupa already presents stumps of wings. To effect its metamorphosis it drags itself out of the water, where it has lived for nearly a year, climbs slowly to some neighbouring plant, and hangs itself there. Very soon the sun dries and hardens its skin, which all of a sudden becomes crisp, and cracks. The dragon-fly then sets free its head and its thorax, and its legs; its wings, still soft and wanting in vigour, gain strength by coming in contact with the air, and, after a few hours, they have attained their full development. Immediately the insect abandons, like a worn-out suit, the dull slimy skin which had covered it so long, and which still

preserves its shape (Fig. 394), and dashes ofl" in quest of prey. The LibellulcB are common all over the world. Their type is the Libellula depressa (Fig. 395), very common in Europe. The male is

423 NEUROPTERA.

brown, with the abdomen blue underneath: the female, of a sort of olive-yellow, bordered by yellow on the sides. Both have the abdomen broad and flattened.

The yEs/ina, with a cylindrical abdomen, attains to the length of two and a half inches. Its flight is more rapid than that of the swallow. The Calepteryx flies more slowly. The male is of a metallic blue, its diaphanous wings are traversed by a band of greenish blue; the female, of a bronzed green, has wings of a metallic

6^=^^

Fig. 396.— Male Raphidia. Fig. 397. —Larva of a Raphidia. Fig. 398.— Pupa of a Raphidia.

green, with a yellowish mark on the edge. These insects rest on reeds, retaining their wings in a vertical position.

The Agriojis, which are of the same family, have the body white, brown, or green, and the eyes very prominent. They are more slim and graceful than the Libellulce^ properly so called ) their larvae are very elongated.

In the spring one meets in the woods with insects having large heads and elongated thoraces. The females have a long auger, with which to deposit their eggs under the bark of trees, where their larvae, which feed on insects, and twist themselves about like small serpents, live. The pupae are also very active; they resemble the adults very Fig. 399.— Mantispa pagana. much, and have the wings laid against the body. These insects, which are met with everywhere, but always in small numbers, are the Raphidtce, which are here represented (Figs. 396, 397, 398) in the state of adult larva and pupa, and the Mantispa (Fig. 399), one species of which is common in the south of Europe.

M. Blanchard classes in the same tribe the genus Semblis, whose" larvae are aquatic, with scaly heads, provided with eyes, and with curved mandibles and short antennae. The larvae and the pupae breathe, like those of the EphemercB, by articulated external processes, or gills, analogous to those of fishes. Nevertheless the pupae live on

Fig. 400.— Semblis lutarius, imago, pupa, and larva.

land, not in water. They hide themselves in the earth at the foot of trees, and the adult issues forth at the end of a fortnight, leaving its pupa skin behind. It lives but a few days. The female lays her eggs on reeds, stones, &c. Fig. 400 represents the Mud Scnib/is in its three states. We now come to those Neuroptera which undergo complete meta-

Fig. 401.— Ant-lion {Myrmeleo formicarins).

morphoses. They are the Myrmeleonidae, of which the Ant-lion {Myrmelco) is the most prominent type, and the Fhryganidcc, or Caddis Flies. The larvae of the Ant-lions live on the land, and are carnivorous. When about to undergo their transformation into pupae, they spin for

42s NEUROPTERA.

theiTj selves a silky cocoon. The larvae of the Phryganea, 011 the contrary, live in the water. They surround themselves with a sort of protecting case, composed of a silky shell and incrustations of all sorts. The pupae, as well as the larvae of these insects, breathe by means of gills. The Ant-lion (Myrmeko formicarius^ Fig. 401) is found in the environs of Paris. It is an elegant insect, resembling the dragon-fly, but is distinguished from it by its antennae. Its larva is of a rosy, rather dirty grey, with little tufts of blackish hair on its voluminous abdomen (Fig. 403). Its legs are rather long and slender; the two anterior pair are directed forwards, whilst the hind legs are

Fig. 402. Ant-lion's funnel. Fig. 403. — Larva, cocoon, and pupa of the Ant-lion.

fixed against the body, and only permit the animal to walk backwards. These larvae are met with in great abundance in sandy places very much exposed to the heat of the sun. There they construct for themselves a sort of funnel in the sand (Fig. 402), by describing, backwards, the turns of a spiral whose diameter gradually diminishes. Their strong square head serves them as a spade with which to throw the sand far away: they then hide themselves at the bottom of the hole, their head alone being out, and wait with patience for some insect to come near. Scarcely has the ant-lion perceived its victim on the borders of its funnel, when it throws at it a shower of dust to alarm it, and make it fall to the bottom of the precipice, which does not fail to happen. Then it seizes it with its sharp mandibles, and

71*

sucks its blood; after which it throws its empty skin out of the hole and resumes the look-out. Ants especially become its prey, whence

NEUROPTERA, 427

its name of Ant-lion. Towards the month of July the larvae make themselves a spherical cocoon, mixed with grains of sand, in which they are transformed into pupae which are hatched towards the end of August (Fig. 403). The ant-lions diffuse an odour of roses; their flight, which is weak, distinguishes them from the dragon-flies. We meet in the south of France with a very beautiful species of Ant-lion, the Myrmeleo libelluloides (Fig. 404); its larva can move forwards, and does not dig itself a funnel (Fig. 405).

The genus Ascalaphus (Fig. 407) is remarkable for the long clubbed antennae of its members, and for their rapid flight. They like the sun, and live especially in hot countries; however, one meets with the Ascalaphus, in the month of July, near Paris, on the dry

Fig. 405.— Larva of Fig. 406.— Larva Fig. 407.— Ascalaphus meridionalis. Myrmeleo libelluloides. of Ascalaphus.

declivities of Lardy and of Poquency. Their larvae (Fig. 406) have mandibles adapted for suction. They watch for insects under heaps of stones, and spring upon their prey.

The first states of the Nemoptera''' (Fig. 408) are not well known. They are insects with wings spotted with yellow and black, the lower ones almost linear, and are met with in southern countries, and but very rarely in the south of France.

The Hemerobii, to which are given by the French the name of Demoiselles ierrestres, or Land Dragon- Flies, are very small delicate insects, of an apple-green colour, with golden red eyes. These insects leave on the fingers, when seized, an oflensive odour. Reaumur calls them Lions des pucerons (Plant-Lice Lions), because their larvae, which resemble the larvae of the ant-lions and live on plants, feed on

From vr\i.(Xy a thread, and Trrepc^j/, a wing.

THE INSECT WORT.D.

428

plant-lice. They attack also caterpillars. Their mandibles are provided with a canal for suction, like those of the foregoing species.

The insects of the genus Osmylus (Fig. 409) are rather rare; but

Fig. 408.— Nemoptera Coa.

may be found in the shrubs which border ponds. They also belong* to the Hemerobiidce. Their larvae live in wet ground.

The Pa7iorpatcE, constitute a singular little family, having a peculiar-shaped head, which is prolonged to a sort of long and

Fig. 410. — Panorpa, male and female.

slender beak. Aristotle called them Scorpion Flies, and thought they were winged scorpions. The. Panorpce^ properly so called (Fig. 410), are found on hedges and plants during the summer.