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swim with great celerity; and, in flying, they make 'a humming or droning noise, like other Beetles.
The larvæ have powerful jaws, and six long legs. At the posterior part of their body, which tapers towards the extremity, there are two small, slender processes, situated somewhat obliquely, and moveable at the base. It is by means of these that the larva suspends itself at the surface of the water, for the purpose of respiring the air of the atmosphere, which it does through two small cylindrical tubes, situated at the extremity of the tail.
When the larvæ change their place in the water, or seek to escape the attack of their enemies, they give a prompt and vermicular motion to their body, and strike the water forcibly with their tail. They are excessively voracious, subsisting chiefly on the larvæ of dragon-flies, ephemeræ, gnats, and other insects. When the time of their transformation approaches, the larvæ quit the water, and enter the earth near the banks of the ponds or ditches which they frequent. Here they form a cavity in the form of an oval case, in which they undergo their change into pupa, and afterwards into winged insects.
Thus these little creatures are aquatic animals in the larva state, become terrestrial under the form of pupœ, and amphibious when perfect insects.
OF THE CARABUS OR GROUND BEETLE TRIBE*.
These insects are very active and voracious, devouring the larvæ of the other tribes, and indeed all the smaller animals they can overcome. They conceal themselves under stones, or moss, and particularly
The feelers are mostly
* The antennæ are thread-shaped. six in number, and the last joint of each is obtuse. The thorax is flat, and both this and the shells are margined.
under such as happen to be near the roots of old trees. Frequently, however, they are to be seen running about on the roads and fields. Some of the species are destitute of wings.
The larvæ are found chiefly in decayed wood, or under the ground, where they undergo their various changes.
THE BOMBARDIER, OR EXPLODING BEETLE *.
This insect conceals itself among stones, and seems to make little use of its wings. When it moves it is by a sort of jump; and, when it is touched, we are surprised with a noise resembling the discharge of a musket in miniature, during which a blue smoke may be seen to proceed from its extremity. The insect may at any time be made to play off its artillery, by scratching its back with a needle. If we may believe Rolander, who first made these observations, it can give twenty discharges successively. A bladder, placed near its posterior extremity, is the arsenal that contains its store. This is its chief defence against its enemies; and the vapour or liquid that proceeds from it is of so pungent a nature, that, if it happen to be discharged into the eyes, it makes them smart as though brandy had been thrown into them. The principal enemy of the Bombardier is another insect of the same tribe, but three or four times its size. When pursued and fatigued, the Bombardier has recourse to this stratagem: he lies down in the path of his enemy, who advances with open mouth to seize him; but, on the discharge of the artillery, the enemy suddenly draws back, and re
*DESCRIPTION. The head, antennæ, thorax, and feet, of this insect, are of a brownish red colour. The eyes are black, and the abdomen and wing-cases blue, nearly black; the latter are marked with broad but shallow striæ. This insect is sometimes found in England.
SYNONYMS. Carabus crepitans. ou Carabe Petard. Latreille.
Linn. Le Bombardier,
mains for a while confused, during which the Bombardier conceals himself in some neighbouring crevice; but, if not lucky enough to find one, the other returns to the attack, takes the insect by the head, and tears it off.
OF THE LYTTA TRIBE.
The antennæ of the Lyttæ are of equal thickness throughout; the feelers are four in number, unequal in size, and the hind ones are clavate. The thorax is roundish: the head inflected and gibbous. The shells are soft, flexile, and as long as the abdomen.
THE BLISTERING LYTTA, OR SPANISH-FLY*.
In the south of France, in Spain, and in Italy, these insects are found in great abundance about the time of the summer solstice. They feed on the leaves of trees and shrubs, particularly on those of the privet, lilac, woodbine, elder, poplar, and ash. On the last-named trees they are sometimes seen in such swarms, as, in a little while, to deprive them entirely of their verdure. They always prefer the young trees to old ones. When collected in great numbers their odour becomes very disagreeable, and is perceptible even to a considerable distance.
In order to collect these insects, a cloth is extended round the foot of the tree, and they are shaken upon it. They are then taken up, tied in a bag, and killed
See Plate xviii. Fig. 3.
DESCRIPTION. These beautiful insects are about an inch long, and of a shining blue-green colour. They sometimes fly in swarms, and have a nauseous smell, not much unlike that of mice. When dried, they are so light, that fifty of them will scarcely weigh a single drachm.
Lytta vesicatoria. Linn. Gmel.-Cantharide vésicatoire. Latreille.-Spanish fly, or Cantharides, in England.
with the vapours of hot vinegar. After this they are dried in the sun, and placed in boxes for use. The fresher the insects are, the more stimulating is the action of their blistering properties. It is consequently necessary to collect them as shortly as possible after they have attained their perfect state.
The ancient Greeks and Romans were acquainted with the qualities of these insects. They are mentioned by Cicero, Pliny, Dioscorides, and Galen.
The odorous particles exhaled by them, are extremely corrosive, and it is necessary to use great caution in taking them up. People have experienced their dangerous effects, by gathering a quantity of these insects during the heat of the sun, with their hands bare, or by having fallen asleep under the trees where swarms of them had settled.
The females lay in a mass, or sometimes separately, their very small eggs, of a cylindrical form, and yellowish colour. These are hatched in about fifteen days.
The larvæ are soft, flat, whitish, and sparingly covered with small bristles. Their bodies are composed of twelve or thirteen segments, of which the three first have each two legs. In this state they appear to live in the earth, where they subsist on the roots of plants.
OF THE FORFICULA OR EARWIG TRIBE.
In this tribe the antennæ are bristle-shaped; and the feelers unequal and thread-shaped. The wing-cases are half the length of the abdomen, and have the wings folded up under them, somewhat in the manner of a fan. The tail is armed with a forceps.
The Earwigs undergo only a semi-metamorphosis, differing in external appearance very little in the three
THE COMMON EARWIG*.
It may not perhaps be generally known that the Earwig possesses wings which are both large and elegant, and that one of these, when extended, will cover nearly the whole insect. The elytra or wing-cases, are short, and extend not along the whole body, but only over the breast. The wings are concealed beneath these, and are somewhat of an oval shape. There is great elegance in the manner in which the insect folds them beneath its elytra. They are first closed up lengthways from a centre close to the body, like a fan; and afterwards refolded across in two different places, one about the middle of the membrane, and the other at the centre, from which the first folds proceeded. By this means the wing is reduced into a small compass, and proportioned to the size of the case under which it is to lie.
It is a circumstance extremely singular, that, unlike those of most others of the insect tribe, the eggs are hatched and the young Earwings are fostered by the parent. At the beginning of the month of June, M. de Geer found under a stone a female Earwig, accompanied by many little insects, which evidently appeared to be her own young. They continued close to her, and often placed themselves under her belly, as chickens do under a hen. He put the whole into a box of fresh earth: they did not enter the earth, but it was pleasing to observe how they thrust themselves under the belly, and between the legs of the mother, who remained very quiet, and suffered them to continue there sometimes for an hour or two together. To feed them this gentleman gave them a piece of a very ripe apple: in an instant the old one ran upon it, and ate with a good appetite; the young-ones also seemed to eat a little, but apparently
* SYNONYMS. Forficula auricularia. Linn.-Twitch, or Twitchball, in some parts of the north of England,