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nominates aptera, because neither males nor females are furnished with wings. This order comprehends thirteen genera, and a great number of species, many of which are very offensive and noxious to the human species. The pediculus, or louse, has six legs, two prominent eyes, and its mouth contains a sting or sucker, by which it extracts blood and other juices from the bodies of animals. Though almost every different animal is infested with a peculiar species of lice, the specific characters of very few of them have hitherto been ascertained. Lice are of various forms; some of them oval, others oblong, and others long and slender. They are oviparous animals, and their eggs are large in proportion to the size of their bodies. Before they arrive at maturity, they change their skin several times.-The pulex, or flea, has likewise six legs, the articulations of which are so exceedingly elastic, that the animal is enabled by their means, to spring to a surprising distance. It has two fine eyes, and its body is covered with crustaceous scales. The flea is the only insect belonging to this order which undergoes a transformation similar to that of the former orders: all the other wingless insects are produced in a perfect state, either by the mother or from eggs. The caterpillars of the flea have forked tails, and are very small and lively. They may be nourished in boxes, and fed with flies, which they greedily devour. Before changing into the chrysalis state, they live fourteen or fifteen days in the form of caterpillars.-The genus called aranea, or spider, comprehends a great many species. The spider has eight feet, and an equal number of immoveable eyes. The chief prey of the spider is flies, animals whose motions are extremely quick and desultory. To enable the spider to observe their movements in every direction, it is furnished with eight eyes, the position of which merits atten

tion: two of them are placed on the top of the head, other two on the front, and two on each side. The mouth is armed with two hooks or fangs, by which it seizes and kills its prey. Round the anus there are several muscular instruments, shaped like nipples or teats: each of these contain about a thousand tubes or outlets for threads so extremely minute, that many hundreds of them must be united before they form one of those visible ropes of which the spider's web is composed. The figure of the web varies according to the species, or the situation the animal chooses for its abode. After the web is completed, some species reside in the centre, and others occupy the extremity of their habitations, where they lie in ambush, with astonishing patience, till a fly is accidentally entangled. The spider, from the vibration of the threads, perceives his prey, rushes forth from his cell, instantly seizes it with his fangs, devours its vitals, and afterward rejects the exhausted carcase. Spiders prey upon all weaker insects, and even upon their own species:

But chief to heedless flies the window proves
A constant death; where, gloomily retired,
The villain spider lives, cunning, and fierce,
Mixture abhorred? Amid a mangled heap
Of carcases, in eager watch he sits,
O'erlooking all his waving snares around.
Near the dire cell the dreadless wanderer oft
Passes, as oft the ruffian shows his front:
The prey at last ensnared he dreadful darts,
With rapid glide, along the leaning line;
And, fixing in the wretch his cruel fangs,

Strikes backward grimly pleased: the fluttering wing
And shriller sound declare extreme distress,
And ask the helping hospitable hand.

THOMSON.

The scorpion is a venomous insect, and a native of warmer climates than those of the north of Europe. It has eight feet, and two claws, the last of which are situate on the forepart of the head. Like the

spider, the scorpion has eight eyes, three of which are placed on each side of the breast, and the other two on the back. The tail is long, jointed, and terminates in a sharp crooked sting. The venom of the scorpion is more destructive than that of any other insect; and is sometimes fatal in Africa and other hot regions.

Such are the divisions into which insects have been classed according to the Linnean system, and such is their structure and conformation. There are many other curious particulars concerning this wonderful part of the creation, which shall be the subject of future discussion. In the mean time, I shall conclude this paper, with a beautiful comparison from the moral Thomson:

Thick in yon stream of light, a thousand ways,
Upward, and downward, thwarting, and convolved,
The quivering nations sport; till tempest winged,
Fierce Winter sweeps them from the face of day.
Ev'n so luxurious men, unheeding pass
An idle summer life in fortune's shine,
A season's glitter! Thus they flutter on
From toy to toy, from vanity to vice;
Till blown away by death, oblivion comes
Behind, and strikes them from the book of life.

No. XXXV.

ON THE TRANSFORMATION OF INSECTS.

Where greatness is to Nature's works denied,
In art and beauty it is well supplied:

In a small space the more perfection's shown,
And what is exquisite in little's done,
"Tis Nature's smallest products please the eye,
While greater births pass unregarded by,
Her monsters seem a violence to sight:
They're formed for terror, insects to delight.
Thus, when she nicely frames a piece of art,
Fine are her strokes, and small in every part.
No labour can she boast more wonderful
Than to inform an atom with a soul;
To animate her little beauteous fly,
And clothe it in her gaudiest drapery.

YALDEN.

IN my two former papers I took a view of the divisions into which insects have been classed, according to the Linnean system. I am now to give a more particular account of what I have hitherto only incidentally mentioned-the various and wonderful transformations which they undergo.

All winged insects, without exception, and many of those which are destitute of wings, must pass through several changes before the animals arrive at the perfection of their natures. The appearance, the structure, and the organs of a caterpillar, a chrysalis, and a fly, are so different, that, to a person unacquainted with their transformations, au identical animal would be considered as three distinct species. Without the aid of experience, who could believe that a butterfly, adorned with four beautiful wings, furnished with a long spiral proboscis, instead of a mouth, and with six legs, proceeded from a disgusting caterpillar, provided with jaws and teeth,

and fourteen feet? Without experience, who could imagine that a long, white, smooth, soft worm, hid under the earth, should be transformed into a black crustaceous, beetle, having wings covered with horny cases?

Beside their final metamorphosis into flies, caterpillars undergo several intermediate changes. All caterpillars cast or change their skins more or less frequently according to the species. The silkworm, previous to its chrysalis state, casts its skin four times. The first skin is cast on the 10th, 11th, or 12th day, according to the nature of the season; the second in five or six days after; the third in five or six days more; and the fourth and last in six or seven days after the third. This changing of skin is not only common to all caterpillars, but to every insect whatever. Not one of them arrives at perfection without casting its skin at least once or twice. The skin, after it is cast, preserves so entirely the figure of the caterpillar in its head, teeth, legs, colour, hair, &c. that it is often mistaken for the animal itself. A day or two before this change happens, caterpillars take no food; they lose their former activity, attach themselves to a particular place, and bend their bodies in various directions, till, at last, they escape from the old skin, and leave it behind them. The intestinal canal of caterpil lars is composed of two principal tubes, the one inserted into the other: the external tube is compact and fleshy; but the internal one is thin and transparent. Some days before caterpillars change into the chrysalis state, they void, along with their excrement, the inner tube which lined their stomach and intestines. When about to pass into the chrysalis state, which is a state of imbecility, they select the most proper places and modes of concealing themselves from their enemies. Some, as the silkworm and many others, spin silken webs or cords

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