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beside that the circumstance of their value to the sick operates to keep down their numbers. Four kinds of our native cantharides have already been used by physicians, and are found as powerful as those which are imported from the south of Europe. One is commonly called the potato-fly, an insect of a yellowish red color, with black stripes on the thorax and wing covers, whence it derives the name striped Cantharis, by which it is most properly known. It eats the leaves of potatoes and other vegetables, and becomes formidable from its numbers. Another is found on our beautiful wild clematis, the lower parts of which they strip of the leaves. The most destructive cantharis is called the ash-colored, and is found on the English bean, on the potato-vine, and also on hedges of the honey-locust, the beauty of which they entirely destroy. Another, of a jet black color, is found on the tall golden-rod, and also on potato-vines, though the former is their favorite food. These different kinds are collected and sold, without the difference between them being noticed. They can be taken by sweeping the plants which they frequent with a deep muslin bag-net, from which they may be thrown into boiling water for two or three minutes, and afterwards spread out on sheets of paper to dry. There are other blistering beetles of the genus Meloe, sometimes called oil-beetles, the most common of which is a blue insect nearly an inch long, found in the autumn on butter-cups and potato-vines, and called the narrow-necked oil-beetle.

The second order, Orthoptera, or straight-winged insects, contains the grasshoppers, and others which are injurious to vegetation, not by reason of their insidious attacks, so much as by their overwhelming numbers. Dr. Harris complains of the confusion occasioned by the misappropriation of names in this family. In America, the name of locust is given to the harvest-fly of English writers, or the Cicada of the ancients, while it ought to be restricted to certain kinds of grasshoppers. Our earwig is not the creature known by that name abroad, and laboring under the absurd reproach which its name implies. The little creeping thing abounding in legs, which we call earwig, is not even an insect, and the veritable earwigs which are found among us are too few to do any barm. The cockroach, one of our imported blessings, hardly comes within our author's sphere, since its labors are wholly domestic; he therefore passes by it, simply recommending

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that a dose of red lead, Indian meal, and molasses, be served up to them, till they have eaten their fill. The cricket, which is commonly thought to be, like the former, an inmate mansions, only enters them by accident ; the field is the scene of his music and operations. The music is produced by grating his wing-cases upon each other, thus producing a discordant sound, which is made tolerable, and even pleasant to some, by means of poetical associations. Their labors are incessant, but not much noticed, because they do not confine themselves to a single plant, but eat almost any which are sufficiently tender. Among the crickets is a small white kind, which conceals itself by day among the leaves and stems of plants, and at night makes a wearisome and incessant noise with its wing-covers. When any one finds its way into a chamber, not even the innocent will find repose that night.

The race of grasshoppers is much the most numerous and important. Favored by their leaf-like form and color, they can easily escape observation, while they devour the foliage, and commit many depredations in a quiet way, which does not attract the attention of the public till they see the great amount of mischief which is done. These insects commit their eggs to the ground, encasing a number together in a sort of varnish, which serves to protect them from decay. These cominonly remain in the ground till the next spring, when the young are ready to begin their labors upon the young vegetation as soon as it rises from the ground. Of this family the Katy-did is the most remarkable. It is well known for the noisy pertinacity with which it sings the syllables which form its name.

The sound is so quarrelsome, and therefore so decidedly human, that it is difficult to persuade one's self there

neither anger nor voice concerned. It proceeds from a thin, transparent membrane, stretched over a portion of the wing-cover. The wing-covers are so very large, as to enclose the whole body of the insect like a pod ; and when these are opened and shut, the parts in question grate upon each other; the sound, being reverberated by the membrane and the concave wings, becomes very loud and shrill, reaching to a great distance, and so exactly resembling a colloquy of scolding vixens, as to be intolerable to a lover of peace. Some seem to bring the charge with great zeal and bitterness,

Katy did, she did," while others with equal exasperation declare, “She did n’t”; and so the matter is debated, very

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much after the fashion of a night session in Congress, with a monotonous repetition of the same empty assertions; and nothing can put an end to it but the morning beams.

Dr. Harris has given a description of the little green grasshopper, with a brown stripe on the head, which'is found in our fields by millions, but has never before been honored with a name.

Or rather there are two; one of which he calls Orchelimum vulgare, the common meadow-dancer; the other, from its form, the gracile, or slender meadow-grasshopper. They do not distinguish themselves by any shrill or troublesome noise, nor are they known to be very injurious to mankind; and these, according to man's usual award in such cases, have lived till now unhonored and unsung.

The various insects included under the name of locust have long and narrow wing-covers, which meet and form a ridge over the back, resembling a roof. The males are not provided with cymbals and tabors like the former ; but instead of these, they have a cavity closed by a thin piece of skin stretched over it, which, like the body of a violin, helps to deepen the sound. When a locust performs, he bends the shank of one hind-leg beneath the thigh, where it is fitted in a furrow designed to receive it, and then draws it up and down the edge and veins of the wing-cover. He does not play both fiddles together, but alternately, first one, then the other. In this country, locusts are not distinguished from grasshoppers ; but, beside the difference of their musical instruments, the locusts greatly exceed the latter in their power of light. Their wing-covers being smaller, do not impair the efforts of their wings, and the wings themselves are moved by strong muscles, and are strongly put together. They do

compare in size and destructiveness with the locusts of Asia ; but we hear at times of extensive ravages made by grasshoppers, which are really owing to locusts, and which show that they can be formidable from their numbers. President Dwight in his “ Travels,” gives an account of an irruption of the kind in Vermont, where they destroyed clover, Indian corn, and even the burdock and tobacco plant ; so voracious were they, that if the garments of laborers were exposed, these insects devoured them. They are no other than the little red-legged locusts, which are found on saltmarshes, where they sometimes consume the grass, and, as they die upon the spot, so taint with their decaying bodies what little they have left, that it is rejected by horses and catlle.

The order Hemiptera, or half-winged, includes the formidable race of bugs, ninety-five species of which are enumerated elsewhere by Dr. Harris, as belonging to Massachusetts. Some, particularly those domestic animals which are called bugs par excellence, are already too well known to need a minute description. Of the out-of-door kinds, the squash-bug is one of the most notorious. De Geer, who first described it, gave it the name tristis, or sad, which would seem to belong more fitly to those who suffer from its visitations. On the return of warm weather, they return from the crevices in which they have passed the winter, and, as soon as the vines have put forth a few rough leaves, they are to be found on the vines, or beneath them, taking no pains to escape, and trusting for security to the acknowledged property, that they are less offensive to the senses while living than when dead. Their eggs are glued to the leaves, where the young are hatched, and, as soon as they come to life, begin to exhaust the leaves of their juices ; as soon as they have drained these, they pass to others, which they destroy in the same way. By taking some care to destroy the eggs and the young, which may easily be done, the insects may be almost exterminated ; but, if this precaution be neglected, the injuries of the insects and the dry weather of summer will destroy the labor of the year.

We observe that Dr. Harris believes in the periodical return of the seventeen-year locusts, as they are called, though locusts they are none. They are of the group Cicada, and are distinguished by their broad heads, large projecting eyes, and most of all by their loud buzzing noise, which is produced by a pair of kettledrums, with which the creature is provided, and which it uses with little discretion. These are formed by convex pieces of parchment, finely plaited, and placed in cavities behind the thorax, where they contract and relax with great rapidity, and produce the sound in question, which can be heard a mile. These insects are first referred to in Morton's “ Memorial,” as pany

of Alies, which, for bigness, were like unto wasps or bumblebees, which appeared in Plymouth in 1633. They came out of little holes in the ground, and did eat up

the green things, and kept up such a constant yelling as made

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the woods ring of them.” It is not clear that they observe the exact interval of seventeen years between the times of their coming. The grub must remain in the earth all the mean while, and perhaps circumstances induce some generations to take wing earlier than others; but it seems to be established that they are, on the whole, entitled to their name. They have no resemblance to locusts in their destructive propensities, which is owing not to any uncommon forbearance on their part, but to the structure of their mouths, which renders it impossible. But they often break the branches of trees with their weight, and the female also inserts her eggs in the boughs, which soon wither and die. When the are batched, they let themselves fall to the ground, going to the lower part of the branch, and taking this leap of Leucate with the utmost coolness and deliberation. When they reach the soil, they immediately burrow into it, and remain there through all the years of their pilgrimage to the last, when they ascend to the surface, where they remain, exposing themselves to the air occasionally till the time of their transformation is come.

When the hour arrives, they come forth by night in great numbers, and crawl up trees, or any thing to which they can attach themselves by their claws; they then by repeated efforts make a rent in their outer integument, through which they push out the head and body, leaving the shell looking like a perfect insect on the tree. A few hours are sufficient to give them strength to fly; within a fortnight they lay their eggs.; and in less than six weeks the whole generation has passed away. It is well that they remain in the ground so long ; it gives time to the trees to recover from the injury occasioned by their burden. In fact it would be no great subject of regret, if the earth to which they betake themselves in the early stages of their existence should become their grave.

The plant-lice, which belong to this order, are a singular generation, and the alliance which exists between some species and the ants has often attracted attention. generally known, that there are some which live in the ground, where they destroy plants by clustering round the roots, in the same manner as others drain the juices from the

This is much more convenient for the ants, who are thus saved the trouble and exposure of climbing trees in search of them, and moreover can have them in their own

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leaves.

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