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beetles he describes, that we might be inclined to doubt the whole of his narrative, or to consider it grossly exaggerated.
The cockchafer is described as appearing suddenly on the south-western coast of Galway in 1688, and gradually spreading through other counties. Thousands were seen hanging on the trees in the day-time, and towards evening they rose, dispersed, and fled about with "a strange humming noise, much like the beating of drums at a distance,' and in such vast numbers as to darken the air. Travellers or persons abroad in the fields were greatly annoyed by them, for numbers would fly with such force in their faces as to occasion pain and to leave a slight mark. But this was a trifling inconvenience compared with that which soon resulted from their visit. They devoured the leaves of the trees, so as to produce a wintry appearance in the country, although it was the middle of summer; and the noise of their feeding is said to have been very surprising, "for the grinding of the leaves in the mouths of this vast multitude all together, made a sound very much resembling the sawing of timber."
Nor were the trees and hedges the only sufferers. They came also into the garden, destroying the leaves, buds, and blossoms of fruit trees, causing in the more delicate species the death of the tree. The beetles came also into the houses, crawling on the walls or ceiling. Sometimes dropping" from the ceiling of the rooms into the dishes as they stood on the table," so extremely offensive and loathsome were they, as well as prejudicial and destructive.
The people of Galway were also dismayed to find that the "creeping spawn" (as Dr. Molyneux terms the larvæ), were even more destructive than their parents. These lying under ground devoured the roots of the corn and grass, depriving both man and beast of support, and bringing the country into a desolate condition. Indeed, had it not been for the timely check given to the perfect insect by high wind and wet weather, which destroyed them by thousands, the plague would have been still more violent and disastrous in its results. During such weather they fell in vast numbers from the trees, and the swine and poultry were so "cunning" that they watched beneath the trees
in such seasons, and ate them greedily, thriving well on this diet.
One of the methods employed at that time for the destruction of the animal was that of burning heath, fern, and other weeds in a corner of the garden or orchard which lay most convenient for the wind to disperse it among the trees. This was found an effectual remedy, preventing the incursions of the enemy, and driving out such as had already taken possession.
THE GAD-FLY OF THE HORSE.
The term gad-fly has been employed to denote the various species of a family of insects parasitic on horses, oxen, and other animals. These insects much resemble large common flies, but the body is often ornamented with bands of different colours, like the humble bees. The wings are very strong, and in general fully extended; the mouth of the insect, when in its winged state, is nearly obsolete, its place being supplied by three small tubercles, which are not fitted for organs of nutrition. Each species of this remarkable family is confined to its own particular quadruped, and displays much skill in the selection of the fittest spot for the deposition of its eggs.
The animals which have been ascertained as subject to their attacks are the horse, ox, ass, rein-deer, stag, camel, sheep, hare and rabbit. Although there is reason to believe that the deposition of the eggs is rather annoying than painful to the several animals, yet the degree of terror which the approach of the gad-fly produces in them is very great. Horses are much agitated at the sight of it: they toss their heads, and gallop to a distant part of the pasture, in the hope of driving it away, or escaping from its pursuit. This is not, however, to be easily effected: the fly often keeps up with their pace, and follows her victim wherever he goes. His only chance of escape now lies in plunging into the stream, and if there is one at hand, he thus effectually rids himself of the annoyance, for the gad-fly never follows him there. If no water is near, the fly soon finds
an opportunity of accomplishing her purpose. Selecting the part where she designs to deposit her egg, she hovers over it for a few seconds, then suddenly darts down and leaves the egg adhering to the hair; this is so rapidly done, that she hardly appears to settle, but merely to touch the hair, and leave the egg affixed, by means of the glutinous liquor which is secreted with it. She then retires to a short distance from the horse, and prepares another egg, which she attaches to the animal in precisely the same way, then another, and so on. Other flies repeat the operation, so that as many as four or five hundred eggs have been placed on one horse. The most wonderful part of this proceeding is, that the insect invariably places the eggs on those parts of the horse's body which are within reach of his tongue. After four or five days these eggs are ready to produce the young worm upon the smallest application of heat, so that when the horse licks that part of the skin on which they are deposited, the eggs readily open. Small active worms issue forth, and clinging to the moist surface of the tongue, they are carried with the food into the animal's stomach. Here, in a heat far surpassing that of our warmest climate, these worms attain their full size, and on this taking place, they detach themselves from the hold they had taken within the animal, and are voided by it. They then seek some convenient situation and assume the pupa state, and after six or seven weeks appear in the form of a fly. There are no less than five species which form the torment of horses, and trouble the short repose allowed to this noble animal. In Germany the grooms make use of a particular kind of brush, with which they cleanse the mouths and throats of the horses, and thus free them from these troublesome insects before they are carried into the stomach.
One species of gad-fly to which the horse is subject, always deposits its eggs on the lips of the animal, and is even more distressing to him than those we have just described. It perseveres in its attempts, notwithstanding all the efforts made to avoid it, and often hides in the grass till the horse is grazing tranquilly, when it fastens on the desired situation.
GAD-FLIES OF THE OX, SHEEP, AND DEER.
The description given by Kirby and Spence of the appearance of a herd of oxen under the attack of gad-flies is true to nature.
At certain seasons, the whole terrified herd, with their tails in the air, or turned upon their backs, or stiffly stretched out in the direction of the spine, gallop about the pastures, making the country re-echo with their lowings, and finding no rest till they get into the water. Their appearance and motions are at this time so grotesque, clumsy, and seemingly unnatural, that we are tempted rather to laugh at the poor beasts than to pity them, though evidently in a situation of great terror and distress. The cause of all this restlessness and agitation is a small gad-fly (Estrus bovis), less than the horse bee, the object of which, though it be not to bite them, but merely to oviposit in their hides, is not put into execution without giving them considerable pain.
This fly has been minutely described by Reaumur, who affirms that, in depositing the egg, the insect bores a small hole in the skin of the ox, by means of a singular organ of a horny texture, somewhat resembling an auger or gimlet. Mr. Bracy Clark does not admit this to be the case, but, after close examination, states that the parent insect merely glues the eggs to the hair of the animal, as in the case of the horse-bee, and that it is not till the living insects appear that the puncture is made. These larvæ are called warbles or wurmals, and after they have burrowed into the skin, they form around themselves bumps or protuberances on the back of the ox, where they enjoy an equal degree of warmth, are protected from inclement weather, and remain till they arrive at maturity, with an abundant supply of food within reach. These tumours vary in number on the animal, from three or four, to thirty or forty. The cattle most covered with them are not disesteemed by the farmer, for it is on young and healthy subjects that they are chiefly found. The tanners also prefer those hides which contain the greatest number of bot-holes, (as they are commonly called,)
as being the best and strongest. The situation of the tumours is generally near the spine, but sometimes upon the thighs and shoulders. The largest of them are nearly an inch and a half in diameter at the base, and about an inch high: they can scarcely be perceived during summer, but in winter attain their full size.
The attack of the fly is attended with some danger, when the oxen are employed in agricultural work; for whether in harness or yoked to the plough, they become unmanageable, and run directly forward.
Nor are our flocks exempt from the annoyance of the gad-fly. Sheep are sometimes observed, in the heat of the day, to shake their heads, and strike the ground violently with their fore-feet; or they will run away to dusty spots, ruts, or gravel-pits, where, crowding together, they hold their noses close to the ground. This is with a view to rid themselves of the fly (Estrus ovis), and to prevent its entering their nostrils, where it lays its eggs around the inner margin. When the larvæ issue from the eggs, they make their way into the head, and when full-grown they fall through the nostrils to the ground, and assume the pupa state. We have no means of knowing whether the sheep suffers much pain from these insects; but from the strange freaks it occasionally performs, when infested by them, there is reason to suppose that they have, to say the least, a teazing and irritating effect. Sometimes the maggot makes its way even into the brain.
The fallow-deer, according to Reaumur, are subject to the attack of two species of gad-fly; one of which deposits its eggs in the same manner as that of the ox, so as to produce tumours; the other, like that of the sheep, so that its larvæ can make their way into the head. There is a curious notion prevalent among the hunters respecting these two species. Believing both insects to be of the same kind, they imagine that they mine for themselves a painful path under the skin to the root of the horns, where they congregate from all parts of the body, and where, by uniting their labours, and gnawing indefatigably, they occasion the annual casting of the horns. Ridiculous as this fable is, it is sanctioned by some authors.
The rein-deer is still more cruelly tormented by these