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

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They have slim bodies spotted with yellow and black, and four straight wings, also spotted with black. In the males the abdomen

Fig. 411. — Pincer of male Panoi-pa. Fig. 412.— Female Panorpa laying.

terminates in a pair of pincers (Fig. 411), which rather remind one of the tail of a scorpion, and are destined to seize their prey, which they kill by piercing with their beak. The female lays her

Fig. 413.— Bittacus tipularis. Fig. 414.— Boreus hiemali.s (magnified and natural size).

eggs in the ground (Fig. 412). In a week the larva makes its appearance it; is a month in developing, it then buries itself still deeper in the earth, and changes into a pupa, which, after a fortnight, comes again into the light in the form of a perfect insect. There are two other genera of Fmiof^patce^ of which Bittacus tiptdaris

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430

(Fig. 413), resembling a large gnat, furnished with four wings, and Boreus hiemalis (Fig. 414), of a brilliant black, met with in Sweden and in the elevated parts of the Alps, jumping about on the snow in considerable troops — are representatives. The latter has been found in England. The FhryganidcE, or Caddis Flies, are known by their larvae, of

Fig. 416. — Phryganeain repose. ihoiiibica

Fig. 415. — Larva of Phryganea rhonibica Fig. 417. — Phryganea rhonibica. (magnified).

which anglers make great use. Reaumur classed them as aquatic moths. The soft and delicate body of the lan^ae is protected by a case, to which they cling by two hooks, placed at the extremity ol their abdomen. They are called by different names in allusion to their habits; as, for instance, case worms, from their living in a case covered with little bits of wood or sand, which they draw after them

as they go. Their scientific name, Phrygafiea^ signifies yi?^^/.* The

From (ppvyapov, a stick.

Ph'yganecE, in the adult state, very much resemble moths. They approach them in having rudimentary mouths, and wings without articulations, but furnished with small hairs, analogous to the scales of Lepidoptera. They may be said to form a sort of connection between the Lepidoptera and Neuroptera. They have been called Mouches papilionacees^ or Papilionaceous Flies. The eggs laid by the female Phryganea are enclosed in gelatinous capsules, which swell in the water and attach themselves to stones, &c. The larva has the appearance of a little worm without feet. It is soon hatched, and resembles at first a little black line, and may be easily reared in an aquarium. The operation of making the silky case which it draws after it, and which protects its abdomen, may then be observed. When it is disturbed, it retreats entirely within its case. The interior is smooth, and lined with mud; on the exterior it is fortified with stones, &c. I The Phryganea rhonibica (Figs. 415, 416, 417) furnishes its case I with bits of wood or grass, arranged as shown in Fig. 418. Some species arrange ; these bits of wood and glass in spiral, ; others in parallel series. The Phryganea fiavicornis covers its dwelling with little shells. " These kinds of dress," says Reaumur, " are very pretty, but they are also excessively singular. A savage who, instead of being covered with furs, should be covered with musk rats, moles, or other entire animals, would have on an Fig. 418, extraordinary costume; this is in some Regular cases of a Phryganea. sort the case with our larvae." Other Phryganece employ for constructing the case which serves them as a dwelling sand and small pebbles; each species always employing the same materials, unless they are entirely deprived of these and obliged to employ others. These cases protect the larvae against the voracity of their enemies. The larvae have a scaly head; and the three first rings of their body are harder than the rest. They live in water, and breathe by means of branchious sacs, arranged on the abdomen in soft and flexible tufts. They eat everything that is presented to them: leaves, and even insects and the larvae of their own kind. The pupae are motionless. They stay about a fortnight in their case, the orifice of which is closed by gratings of silk, then break through the gratings, and leave their prison. In this state (Fig. 419) they swim on the water until they meet with an object to which they can attach them-

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452 selves, and so get out. Then they swell till they crack their skin over the back, and the perfect insect emerges.

The Phryga7iea pilosa (Fig. 420) is of a yellowish grey, with hairy wings, little adapted for flying. These insects do not eat, and never leave the neighbourhood of the water. During the day they rest on

419. — Pupa of Phryganea Fig. 420.— Phryganea pilosa. pilosa, magnified.

flowers, on walls, or on the trunks of trees, their wings folded back, and their antennae together. In the evening they fly in dense swarms over streams and ponds. They are attracted by light, as are many nocturnal insects; and are sometimes found in great numbers on the lamps on the quays in Paris.

The Hydi'opsychcs (Fig. 421) and Rhyacophili (Fig. 422) are small insects which resemble the Phryganece. very closely. Their larvne have, for the purposes of respiration, some gills, others retracti; tubes. They construct for themselves fixed places of shelter, moi t or less imperfect, at the bottom of the water, and against large stones.

Fig. 421.— Hydropsyche (Phryganea) atomaria, larva, pupa, imago, and larva-case.

Fig. 422.— Rhyacophilus vulgatus, larva, pupa, cocoon, and imago (male).

which they leave occasionally for a few moments. Sometimes these cases contain several larvae. Fig. 421 represents the various states K)i a Hydropsyche; the larva is seen on the left, the pupa on the right, the winged insect in the middle. Two of the insect's tents, or places of shelter, are represented below. Fig. 422 shows the different states of Bhyacophilus vulgatus, larva, cocoon, pupa, and imago. The genus Rhyacophilus has this peculiarity, that the larva spins itself a cocoon in the interior of its dwelling before changing into a pupa.

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IX.

COLEOPTERA.

In collections of insects the Coleoptera almost always occupy the principal place. They are sought after by collectors on account of the brightness of their colours, of the solidity of their integuments, and the facility with which they can be preserved. This circumstance has contributed much to give to the Coleopterous Order marked preponderance in the immense series of insects. Many more have been collected than any one has as yet been enabled to describe; and the collections are encumbered with species of which no naturalist has yet given an account. Admitting that the first-rate collections contain each about 25,000 perfectly distinct species, and that a certain fraction of these treasures is peculiar to each collection, M. Blanchard came to the conclusion that we must estimate the number at more than 100,000 of the species of Coleoptera which would be obtained if the different entomological collections of France, England, and Germany were put together. But every day we see arriving from different regions of the globe new riches, hardly dreamt of up to that time; and it is not only the small species, but the larger and more beautiful also, which furnish their contingent. It may, then, be believed that, if the entire surface of the earth were carefully explored, we should obtain an incalculable number of Coleoptera, having sufficient characteristics to constitute distinct species or kinds.

The Coleoptera (from KoXeos, a sheath, and TrrepoV, a wing) are insects with four wings. The anterior wings, or elytra, are not used in flying; they are sheaths, more or less hard, sometimes varied with bright colours, and never crossing over each other. The posterior wings are membranous, presenting a ramification of veins, and usually folding up under the elytra, which protect them when at rest. The mouth of Coleoptera is provided with mandibles, with jaws, and two quite distinct lips, and is suited for mastication. They undergo complete metamorphosis. After an existence of greater or less extent

in the larva state (in the case of the cockchafer three years), the insect changes into a pupa, which remains in a state of complete immobility. After a certain time, the pupa bursts its envelope and assumes the form of a perfect insect. The Coleoptera present the utmost variety of habits as regards their habitations and food. One does not find in this Order those admirable instincts, those manifesta-tions of intelligence, which bring certain Hymenoptera near to those beings which are highest in the animal scale; but they offer peculiarities very well deserving serious and profound study. Some are carnivorous, and thus they are useful to man in destroying other noxious insects, which they seek on the ground, on low plants, on trees, and even in the depths of the waters. Many of these Coleoptera feed on animal matter in a state of putrefaction. We may look on them as useful auxiliaries: they are Nature's undertakers.

A great number live in the excrements of animals. The dung of oxen, buffaloes, and camels affords shelter to Coleoptera of different families, which thus live on vegetable matter more or less animalised. Others attack skins and dried animals in general; and some are the pest of entomological collections. Lastly, immense legions of Coleoptera are phytophagous; that is to say, they attack roots, bark, wood, leaves, and fruits, and cause much annoyance to the agriculturist. Above all, the larvae are to be dreaded. Those which live in wood may in a few years occasion the loss of trees, vigorous and full of life; or completely destroy the beams of a building. Certain larvae, such as those of the cockchafer, eat away the roots of vegetables, and so destroy the harvests. Others, lastly, devour the leaves and the stalks of plants, attack the flowers in the gardens, or the corn in the barns; and so man makes desperate war against them.

In the immense variety of known Coleoptera we must be contented to choose those types which are most prominent and most characteristic. We will begin with the Scarabceides^ with their heavy compact body, and short antennas, terminated by a foliaceous club. \ It is to this tribe that belongs the beautiful Rose Beetle {Cetonia aurata), which lives on roses; the Cockchafer {Meioiontha vulgaris); the Scarahceus of the Egyptians; &c.

This is the most interesting tribe of the whole Order Coleoptera. It corresponds with the great division of the Lamellicornes of Latreille. This name of Lafnelliconies was intended to remind us of the arrangement into laminae, more or less close together, of the club of the antennae of these insects. Many Scarabcei have their mandibles membranous, or at least partially so, and always small. This peculiarity corresponds to their habits. Never, indeed, have they to