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 this time the female Coccus, having attained its greatest size, will become easily perceptible, and each of them should be carefully removed by a blunt knife, having a very thin blade, and should be carefully deposited in a vessel, for the purpose of being carried out of the garden. With each female, which is destroyed at this period, it is supposed that at least 3000 eggs are also destroyed. THE COCCUS OR COCHINEAL OF THE APPLE-TREE There is, says Dr. Anderson, in his Recreations in Agriculture, an insect belonging to the Coccus tribe, which has of late multiplied extremely in the nurseries about the metropolis, and which, unless carefully guarded against, threatens to be extremely destructive to our orchards. It lives upon the apple-trees, 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 still involved in obscurity; and the changes it undergoes, and its modes of life during the various stages of its existence, are not yet distinctly known. The following particulars concerning it, are, however, related by Dr. Anderson. Wherever this insect has fixed itself upon a tree, it communicates a corrosive ichor, that, after the insect itself is removed, affects the tree like a kind of gangrene; so that the tree becomes blotched, uneven in the bark, and full of deep holes, that soon occasion its decay and death. The insect fastens itself, by preference, upon the tender buds of young trees, immediately under the axillæ of the leaves on the shoots of that year, and *Coccus mali. very quickly infects them. It, however, takes such slight hold, that if it has not had time to bury itself in holes in the bark, it may be easily removed by means of a firm, dry painter's brush; so that the shoot shall sustain no damage from it. Rain also washes it off from smooth surfaces; and, during moist weather, a wet brush may be efficaciously employed for the same purpose. Next to the eyes on the young shoot, this insect is found to establish itself in any cavities of the stems or larger branches of trees, which have been produced by tearing off the branches incautiously, or in any other wound in the bark. In these irregular cavities it finds a protection from rain; and from these, when the insects are once established, it is very difficult to dislodge them; so that such cavities may be considered as the nests, from which they send out swarms to spread over the young branches. It would be a great preventive against the attacks of the insects, to scoop out all such cavities to the quick; to cut off all irregular prominences; to scrape off the loose scales from the bark, and then to cover it with a composition invented by Mr. Forsyth, which would not only destroy the insects, but by bringing on a smooth, clean bark, would admit of its being afterwards washed and cleaned without difficulty. Lepidopterous Insects *. The present order contains only three tribes; the Butterflies, Sphinges, and Moths. These are all pro The insects of the Linnean order Lepidoptera, have four wings, each covered with fine scales, apparently like fine powder or meal. Their bodies are composed in general of twelve membranaceous rings, which sufficiently distinguish duced from caterpillars, by a change that is common to all the insect species. The caterpillars proceed from eggs; and the eggs of Butterflies are sometimes so numerous, that, in the spring of the year, the leaves and tenderest stems of plants are nearly covered with them. Caterpillars are, in general, extremely voracious. Some of them eat more than double their own weight in a day, and this without suffering any inconvenience; for the digestive powers of all animals are proportioned not so much to their size, as to the duration of their lives. They often change their skin without much altering their shape, till at last they assume a shape very different from that which they before possessed. They have now the name of Aurelia or Chrysalis; and in this state all the parts of their future form are visible, but under a thick shell: and these are so very soft and delicate, that the least touch discomposes them. The production and manners of these animals, afford subject both of amusement and instruction. About the middle of summer, a butterfly deposits from three to four hundred eggs on the leaf of a tree; from each of these, in a few days, a young caterpillar proceeds. The eggs of one of the species are no sooner hatched, than the young-ones begin to form a common habitation. They spin silken threads, which they attach to one edge of the leaf and extend to the other. By this operation they make the two edges of the leaf approach each other, and form a cavity resembling a hammock. In a short time the concave leaf is completely roofed with a covering of silk. Under this tent them from all such creatures as bear the least resemblance to them. Their head is scarcely to be distinguished from the body, but by its containing an opening, in which are two jaws, each armed with a large and thick tooth. The number of their feet varies with their size and form. Along their sides are arranged holes or trachea, through which they breathe, the animals live together. When not disposed to eat or to spin, they retire into their tent. It requires several of these habitations to contain the whole. As the animals increase in size, the number of their tents is augmented. But these are only temporary and partial lodgments, constructed for mutual convenience, till the caterpillars are in a condition to build one more spacious, which will be sufficient to contain the whole. After having gnawed one half of the substance of such leaves as happen to be near the end of some twig or small branch, they begin their great work. In constructing this new edifice or net, the caterpillars encrust a considerable part of the twig with white silk. In the same manner they cover two or three such leaves, as are nearest to the termination of the twig. They then spin silken coverings of greater dimensions, in which they enclose the two or three leaves together with the twig. The nest is now so spacious that it is capable of containing the whole community, every individual of which is employed in the common labour. These nests are too frequently seen in autumn upon the fruit-trees of our gardens: they are still more exposed to observation in winter, when the leaves which formerly concealed many of them are fallen. They consist of large bundles of white silk and withered leaves, without any regular or constant form. By different plain coverings, extended from the opposite side of leaves and of the twig, the internal part of the nest is divided into several different apartments. To each of these, which seem to be very irregular, there are passages, by which the caterpillars can either go out in quest of food, or retire in the evening, or during rainy weather. The silken coverings, by repeated layers, become at last so thick and strong, that they resist all the attacks of the wind, and all the injuries of the air, during eight or nine months. About the beginning of October, or when the frost commences, the whole community shut themselves up in the nest. During the winter they remain immov able, and seemingly dead; but, when exposed to heat, they soon discover symptoms of life, and begin to creep. They seldom go out of the nest till the middle or end of April. When they shut themselves up for the winter, they are very small; but, after they have fed for some days in spring, upon the young and tender leaves, they find the nest itself, and all the entrances to it, too small for the increased size of their bodies. To remedy this inconvenience, these creatures know how to enlarge both the nest and its passages, by additional operations accommodated to their present state. Into these new lodgings they retire, in order to screen themselves from the injuries of the weather, or to cast their skins. In fine, after having cast their skins several times, the period of their dispersion arrives. From the beginning to nearly the end of June, they lead a solitary life. Their social disposition is no longer felt. Each of them spins a pod of coarse brownish silk. In a few days they are changed into chrysalids, and in eighteen or twenty days more they are transformed into butterflies. The modes adopted by caterpillars to screen themselves from observation, are as various as they are interesting. Many of them feed enclosed within the stems of herbaceous plants; others in the branches or trunks of trees; a few within fruits and the buds of flowers: some on the roots of plants; others float on the surface of the water, between the leaves of aquatic vegetables, woven around them with inimitable art; and a great number escape our notice, by taking their nourishment only in the night. And though many feed on the leaves of plants and trees in the day-time, yet some, as if conscious of the similarity of their colour to that of the undersides of the leaves, and of the safety they derive from attaching themselves thereto, are seldom to be seen but in that situation. Many of the moths, whose colours bear a resemblance to those of the trunks or branches of trees, frequently fix themselves there, and remain motionless for several hours |