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proceeds its forked leg. The horns are branched in a peculiar manner, and the insect can move them in all directions, so as to contribute materially, by their action, to that jerking motion in the water, whence this species of monoculus bas derived its trivial name. In the body of the female the bunch of eggs is very plainly seen through the transparent shelly covering. The eyes are formed of little black globules, situated very near to each other, and invested with a common membrane, which gives them the appearance of unity.

The onisci, or wood-lice, are of very retired habits. They but seldom appear in the day-time, seeming to shun both the light and heat of the sun. They are mostly found under stones, in the crevices of walls, in cellars, and in subterraneous places. When undisturbed they move slowly, and their many legs seem but of little comparative use to them even in flight. The majority of the species are either so sensible, or so timid, that they roll themselves up as soon as they are touched; and, like the hedge-hog, present a ball without the slightest appearance of head or feet. In this state they remain till they think the danger past, when they gradually unfold, and slowly walk away. The onisci feed on different substances; on leaves, on plants, and on fallen fruit. Most of them live on the earth, but some inhabit the water. Of these, the o. aquaticus is sometimes seen, like a small shrimp, swimming in our cisterns; while the marine species, the o. entomon, of comparatively gigantic size, measuring nearly two inches, is found about rocks, and under the arches of bridges, &c., subject to the tide. - We have now described the principal genera of British Insects, and shall add some remarks on the language of insects, their torpidity during the winter season, and their sudden revival when exposed to heat.

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Language of Insects. . Those insects which are brought forth, and live in society, who mutually assist each other in construct ing works for the common good and accommodation, seem to have the greatest need of an extensive language. Being destined to form one large family, to give mutual aid and support to each other in all their common wants and operations, a species of language, and that not very limited, seems to be ab. solutely necessary to enable them to understand and to execute the different labours allotted to them with that regularity and harmony, which is so remarkable in the magnificent structures erected by bees, wasps, and many other gregarious insects. Bees, as well as flies of every kind, make a humming noise by the vibrations of their wings. But the noise of the bee, when flying home with its load, is very different, even to our comparatively blunt ears, from that which it utters after arriving at the hive, where it makes a peculiar noise, which is perfectly understood by the working bees, who instantly come and carry off this fresh supply of materials.

Common flies, and particularly the large flesh-flies, make a soft singing kind of noise when flying about in tranquillity. But, when alarmed, or when entangled in the web of a spider, the noise of their wings intimates distress and terror. Instead of being soft and agreeable, it is then loud, quick, harsh, and interrupted, precisely analogous to the language and cries of men and of the larger animals when placed in similar circumstances. Mr. Smellie' thinks it more than probable that the common housefly is endowed with the faculty of hearing. Whenever we perceive that effects and movements are uniformly produced by certain sounds, it may be concluded that the animal is furnished with organs of

1 Philosophy of Natural History, vol. ii, p. 434.

· hearing, though, from their minuteness, we are un

able to discover where they are situated. In the winged tribes of insects, it is probable that the organs of hearing are placed near the insertion of the wings, or, at least, that nerves or vessels proceed from the wings to the more immediate organs of hearing, which may be inclosed under that elastic, crustaceous substance with which the head is covered. This idea will be rendered still more probable by attending to the various modulations of sounds produced by the vibrations of the wings, and by comparing these with the present situation and employment of the insect. When a common fly is irritated or terrified, the noise made by the vibrations of its wings is very different from that produced when the animal is flying about undisturbed. When a house or a flesh-fly is tormented by thoughtless children, who, for amusement, often insert pretty large pins into the bodies of these insects, which the animals, with much pain, are obliged to trail after them, the noise of their wings is then highly expressive of im. patience and of torture. But when they meet with food agreeable to their taste, the sound of their wings is soft, gentle, and even melodious. When a fly wishes to express joy, the noise of its wings is brisk and sharp, and easily distinguishable from that produced by the insect when it is excited by terror or any embarrassing or painful sensation. Though the eyes of flies consist of numerous lenses, so situated that they can see objects all around them, yet these lenses are so minute and so convex, that they can perceive objects at small distances only.

The ticking noise produced by some insects, which has been already noticed, is, without question, a kind of language. Some spiders, when they wish to communicate with each other, have a mode of striking against the wall nine or ten times, which signal is immediately understood by their compa


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state:ealed cornet xhen expositered spot: nter months

Torpidity of Insects. Spiders pass the winter season in a dormant state, inclosed in their own webs, and placed in some concealed corner. Like the torpid mammalia, they speedily revive when exposed to intense cold, and strive to obtain a more sheltered spot. Many insects which are destined to survive the winter months become regularly torpid by a cold exceeding 40°. The house-fly may always be found in the winter season, torpid, in some retired corner; but exposure for a few minutes to the influence of a fire recals it to activity. Even some of the lepidopterous insects, which have been hatched late in the season, possess the faculty of becoming torpid during the winter, and thus have their life prolonged beyond the ordinary period. These insects can all be preserved from becoming torpid by being placed in an agreeable temperature, as the following experiments of Mr. Gough' testify. In speaking of the hearth cricket he says, " They who have attended to the manners of this familiar insect will know that it passes the hottest part of the summer in sunny situations, concealed in the crevices of walls and heaps of rubbish. It quits its summer abode about the end of August, and fixes its residence by the fireside of the kitchen or cottage, where it is as merry at Christmas as other insects are in the dogdays. Thus do the comforts of a warm hearth afford the cricket a safe refuge, not from death, but from · temporary torpidity, which it can support for a long time, when deprived by accident of artificial warmth. • I came to the knowledge of this fact,' he says, ' by planting a colony of these insects in a kitchen, where a constant fire is kept through the summer, but which is discontinued from November to June, with the ex. ception of a day once in six or eight weeks. The crickets were brought from a distance, and set at liberty in

Nicholson's Journal, vol. xix, p. 162,

this room in the beginning of September 1806: here they increased considerably in the course of two months, but were not heard or seen after the fire was removed. Their disappearance led me to conclude that the cold had killed them: but in this I was mistaken; for, a brisk fire being kept up for a whole day in the winter, the warmth of it invited my colony from their hiding-place, but not before the evening, after which they continued to skip about and chirp the greater part of the following day, when they again disappeared; being compelled by the returning cold to take refuge in their former retreats. They left the chimney-corner on the 28th of May, 1807, after a fit of very hot weather, and revisited their winter residence on the 31st of August. Here they spent the summer merely, and lie torpid at present (Jan. 1808) in the crevices of the chimney, with the exception of those days on which they are recalled to a temporary existence by the comforts of a fire.'

· At the commencement of our Introduction, several of the advantages to be derived from the study of Entomology were pointed out, particularly as it regards a more perfect acquaintance with the Insects of our native country, but there is one other benefit to be derived from this pursuit, which is too important to be passed over,-its value in the education of youth. This has been forcibly stated by · Messrs. Kirby and Spence, in the preface to their amusing · Introduction to Entomology, and with these sensible observations we shall conclude. All modern writers on the momentous subject of Educa. tion unite in recommending, in this view, Natural History; and if the quality of accurate discrimina tion-the ready perception of resemblances among diversities, and still more the quick and accurate perception of diversity in the midst of resemblances

constitutes one of the most important operations of the understanding; if it be indeed the foundation

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