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times migrate, and suddenly fall in showers on spots that were until then free from their ravages. The gardeners have proposed several compositions for washing the infested trees; but plain water, dashed with force from a garden engine, will prove as destructive to them as any thing, when on trees; and smaller plants may be washed with tobacco water, with elder leaves infused in water, or with common soap suds, either of which will destroy the insects. We might, perhaps, effect much towards freeing our gardens from this pest, by encouraging the breed of such other insects as feed upon these tree-lice. The larvæ of the lady-bird eat thousands of them; some species of ichneumon and common ants also destroy them; it would, therefore, be well worth the experiment to learn more of the habits of these insects, particularly to discover whether they are themselves injurious to gardens, and then to introduce such of them as are innocuous to the spots that are infested with the lice. It would probably prove serviceable to scatter ants, which may always be procured in abundance, upon the infested trees, with this view. The aphides sometimes settle upon the tops of beans, covering them so thickly, as to make them appear quite black : in such cases the crops may often be preserved by cutting off the tops, a practice which is likewise adopted independently of this pest requiring it, for the purpose of increasing the yield of beans'.
The rose tree, which produces so many beautiful flowers, is, after a mild spring, greatly injured by a species of aphis (a. rose). The best mode of remedying this evil, is to lop off the infected shoots before the insects are greatly multiplied, repeating the same operation before the eggs are deposited. By the first pruning a very numerous present increase will be prevented, and, by the second, the following year's
i Dr. Skrimshire's Essays on Natural History, vol. i, p. 149..
supply may, in a great measure, be cut off. If it were not for the numerous enemies to which the aphis is exposed, their wonderful fecundity is such that the leaves, branches, and stems of every plant would be totally covered with them. Myriads of insects, of different classes, of different genera, and of different species, seem to be produced for no other purpose than to devour the pucerons. On every leaf inhabited by them, we find worms of different kinds. These worms feed not upon the leaves, but upon the pucerons, whom they devour with an almost incredible rapacity. Some of these worms are transformed into insects with two wings, others into flies with four wings, and others into beetles. While in the worm state, one of these gluttonous insects will suck out the vitals of twenty pucerons in a quarter of an hour. Reaumur supplied a single worm with more than a hundred pucerons, every one of which it devoured in less than three hours.
Of the coccus or cochineal tribe there are two species, which are very destructive in our gardens, the c. persicæ, or peach-coccus, and the c. mali, or apple-coccus. If we cannot eradicate the peachcoccus, we may, perhaps, reduce its numbers by carefully brushing the twigs of the peach tree, early in the spring, with a hair brush, in the direction of the buds, as many of the insects might thus be detached. Where the insects are very numerous, and where, of course, they are placed very close together at the points of the twigs, these points might be cut off, and carried out of the garden. If exceedingly numerous, all the young twigs might be cut out. In this case, it is true, the fruit will, in a great measure, be lost for that season: but the tree will be thrown into such health, as to be in the finest possible order for the ensuing year. After all this has been done, however, the tree ought still to be examined about the beginning of May, next season; by which time the female coccus, having attained its greatest size,
vessel, fry thin blade by meansach of then
will become easily perceptible, when each of them should be carefully removed by means of a blunt knife, having a very thin blade, and carefully deposited in a vessel, for the purpose of being carried out of the garden, With each female which is taken at this period, it is supposed that at least 3000 eggs are also destroyed.
The apple-coccus lives upon the apple tree, and, like most of the insects of this kind, throws out such a quantity of cotton-like matter, as sometimes to cover every twig of the young trees, as if they had been rolled up in cotton. The history of this insect is, at present, involved in much obscurity; but let us hope that a more attentive examination of its manners and habits will, at no distant period, enable us to guard against its extensive depredations.
ORDER III.-LEPIDOPTERA. The insects of this order are particularly distinguished by their scaly wings, from which alone they derive their name of Lepidoptera. These wings are four in number, and are generally variegated by the most brilliant colours, entirely produced by an infinity of little oyal scales, either of a conical or triangular shape, and placed one above another, like the tiles on the roof of a house. These scales, which may be called the feathers of the butterfly, are fixed on a kind of pedicle, but come off on the fingers, like a farinaceous powder, with the slightest touch, leaving the bare wing, a thin, transparent, elastic membrane, devoid of beauty, and studded with longitudinal rays, showing the places to which the scales were formerly attached. The mouth in these insects is a sort of trunk, which is not unaptly called a spiral tongue, since when not in action it is completely rolled up and placed between two palpi, or downy feelers, which hide it entirely. This trunk, which differs in length, and is sometimes very short, is composed of
two pieces, or laminæ, convex on one side, and concave on the other. These laminæ are easily sepa: rated at the will of the insect, and, when re-united, form a hollow cylinder. The insects belonging to the order Lepidoptera are so elegant in their appearance, and perfect in their shape, that they claim the highest rank among the numerous' and extensive class to which they belong. Such is their variegated beauty, and such the softness of their blended tints, that we might almost' fancy them ethereal beings, who, in their passage through infinite space, had stained their wings in the colours of the rainbow. :. The Lepidoptèra are perfectly harmless, and have no organ with which they can either injure others or defend themselves. Their aërial state is comparatively transient: it is during that short but gay pe-riod of perfection and enjoyment, when they may be seen in pairs, fluttering from flower to flower, and, with their long-extended tongue, searching each nec
tary, and extracting the sweets from 'every cup'. ! • Many thousand species of butterflies are known in Europe, and, in England alone, more than eleven hundred have been collected by a celebrated entomologist. **?
The larvæ or young of the different kinds of butterflies and moths, when in that state in which they *come from the egg, are called caterpillars. These, 'which are very minute at first, feed generally on the leaves of vegetables, and increase in size. They cast their skins occasionally, and sometimes change in colour and markings, but never in their general appearance or in their habits. Eating seems to be their sole employment; and when they meet with food that suits their palate, they are extremely voracious, committing great havock in our gardens. But the same infinite Wisdom which restrains the depredations of the aphides and other insects, has also set
"Wood's 'Linnaan Genera of Insects, vol. ii. p. l.
bounds to the destruction occasioned by the caterpillar, who has myriads of internal as well as external enemies. Many flies deposit their eggs in the bodies of caterpillars. From these eggs proceed small maggots, which gradually devour the vitals of the animal in which they reside. When about to be transformed into chrysalids, they pierce the skin of the caterpillar, spin their pods, and remain on the empty skin till they assume the form of flies, and escape into the air to perform the same cruel office to another unfortunate reptile. Every person must recollect to have seen the colewort or cabbage caterpillar stuck upon old walls, or the windows of country cottages, totally covered with these chrysalids, which have the form of small maggots, and are of a fine yellow colour. One of the most formidable enemies of the caterpillar is a black worm, with six crustaceous legs : it is as long and thicker than an ordinary sized caterpillar. In the fore part of the head it has two curved pincers, with which it quickly pierces the belly of a caterpillar, and never quits the brev till it is entirely devoured. The largest caterpillar is not sufficient to nourish this worm for a single day; for it daily kills and eats several of them. These gluttonous worms, when gorged with food, become inactive, and almost motionless. When in this satiated condition, young worms of the same species attack and devour them. Of all the trees, the oak, perhaps, nourishes the greatest number of different caterpillars, as well as of different insects. Among others, the oak is inhabited by a large and beautiful beetle. This beetle frequents the oak, probably because that tree is inhabited by the greatest number of caterpillars. It marches from branch to branch, and, when disposed for food, attacks and devours the first caterpillar that comes in its way. .
When full grown, the caterpillars seek some retreat, to prepare for an important change, viz. from the soft caterpillar, possessing motion and feeding