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which deposit their eggs in the branches or leaves of trees, place them in a small hollow which they form by means of an instrument at the posterior part of their body. Each egg is fixed to the spot by a kind of gluey matter with which it is covered. The juices of the leaf or stem overflow by the small vessels which are opened in this operation, and thus form a gall or excrescence, in which the egg becomes inclosed. When the larva is hatched, it finds around it the food that is necessary for its subsistence. It gnaws and lives upon the substance of the gall, which increases in bulk and consistence, in proportion as its interior is thus destroyed. Some of these galls have, in their interior; either only one cavity in which many larvæ are inclosed together, or many small cavities, having a communication with each other; some have many separate cavities, and others have only one cavity, which is occupied by a solitary insect. When the larvæ have attained their full growth, some of the species eat their way out, and drop upon the earth, in which they bury themselves, and there undergo their metamorphoses; and others are transformed within the galls, and leave them only as perfect insects. The species of ground ivy and the oak have each. a peculiar gall-insect, C. glechomatis, and.c. quercus folii, the latter appearing pot unlike a rose-bud when beginning to blow".
Some of the species of the genus tenthredo or saw fly, by means of a saw which they possess, deposit their eggs in the buds of flowers, while others insert them into the twigs, of trees or shrubs. The gooseberry tree saw-fly (t. grossularie) makes great havock among its favourite plants; but its sluggish nature rendering it an easy prey to birds, its devas. tations are materially diminished. . .
The rose-tree has also its tenthredo: the female may be seen in a fine summer morning, about ten o'clock, running with eagerness over all the branches
The excrescence vulgarly denominated oak-apple, is the work of an insect of the genus cynips.
of the rose, and generally selecting that which is near the extremity of the principal stem. Here she makes an opening with her borer, and, when she considers the hole of a proper size, deposits an egg in the cavity. She then remains perfectly quiet for some minutes, with the borer still in the hole; after this pause she partly withdraws the instrument, and in the act emits a frothy liquor which fills the cavity. The use of this liquor is not well understood, but, as soon as it is emitted, the insect wholly withdraws her borer, to repeat the operation in another place. Of these holes, she will make from four to twenty by the side of each other. That part of the rose-branch where the, deposition has been effected begins to turn brown on the following day, and the wounds it has received begin to rise and increase in convexity from day to day, till in due time the inclosed egg gives birth to a larva, which bursts its green covering to seek its food on the surface of the rose-leaf. The larvæ of the tenthredines bear a strong resemblance to caterpillars, but have a greater number of feet. They inhabit different trees according to their species; and some of them exhibit in their economy peculiarities deserving of notice'.
Instinct leads the different species of the ichneumon to provide for their future progeny in a manner distinct from each other. Some lay their eggs in the crevices of walls; others insert their long borers into the clefts of trees, and there deposit their burthen ; while a third division, and that the most singular in the adoption of its object, singles out an unlucky caterpillar, and the female ichneumon, plunging her long tube into its body, introduces egg after egg, and, notwithstanding all the attempts of her victim to rid itself of its tormentor, continues her operation till her whole stock of eggs is deposited.
parati con tanto The numerous larvæ, which originate in the body of the caterpillar from the eggs thus laid, and which
* Wood's Linnæan Genera of Insects, vol. ii, pp. 45, 46. ..
live at its expense, and feed on its substance, do not, as one might reasonably suppose, destroy the animal directly, but, carefully avoiding the immediate destruction of that, which would at the same time be death to themselves, they leave the vital parts and principal viscerà untouched, feeding only on that fatty substance with which the body of the caterpillar is plentifully provided. - This substance furnishes nourishment enough for the larvæ to exist till they have attained their full size; and when they are ready for their usual transformation they pierce the skin of the caterpillar with their teeth, and, creeping out in various places, spin themselves a silken covering, in which they pass the chrysalis state. In the mean time the languid and shrivelled caterpillar, with its body like a sieve, after having yielded all its substance to its parasitical companions, is in a short time relieved from its sufferings by death.The insects of this genus are, for the most part, remarkable for the continued vibration of their antennæ.
What has been said of the ichneumon will apply, for the most part, to the chrysis; their habits and metamorphosis being much the same. The chryses áre, however, far more beautiful insects, and are in general distinguished by the most brilliant metallic colours. They are generally seen in the hottest part of a summer day flying about walls, or near decayed wood, in the crevices of which the female deposits her eggs. Their movements are lively, and their flight rapid. The golden chrysis (c. ignita) is represented in fig. 5 of our Frontispiece. .
Of the manners of the sand-wasp (sphex sabulosa), common in some 'counties of England, but rarely seen near the metropolis, Mr. Ray furnishes the following curious anecdote. I observed one of them,' says hé, dragging a green caterpillar thrice its own size." It laid this down near the mouth of à burrow that it had made in the ground: then, removing a little ball of earth with which it had co
vered the orifice, it first went down itself, and, after staying a short time, returned, and, seizing the caterpillar again, drew it down also. Leaving the caterpillar there, it came up again, and, taking some little globules of earth, rolled them one by one into the burrow, scraping the dust in at intervals with its fore-feet, in the manner of a dog; thus alternately rolling in pieces of earth, and scraping in dust, till the hole was full; sometimes going down (as it seemed) in order to press down the earth; and once or twice flying to a fir-tree which grew near, perhaps for the purpose of getting turpentine to glue it down, and make it firm. The bole being filled, and equalled with the superficies of the earth, that its entrance might not be discovered, it took two fir-leaves that were near, and laid them by the mouth, most probably to mark the place.
Of the wasp (vespa), Mr. Wood furnishes us with a succinct but pleasing description. Wasps build their upright oval nests of bits of wood and glue. The males are employed to collect the wood from the frames of windows, and from old posts and rails. They use their strong jaws to cut the wood, and carry away the saw-dust with their feet, making it into a mass at the nest, with a glutinous liquor which falls from their mouth. The nest is twelve inches or more in diameter, and is formed of several horizontal stages of hexagonal cells. The substance of the nest, after being kneaded and worked by the industrious inhabitants, is very like coarse whitishbrown paper. In each cell the female deposits an egg, which is hatched into a larvæ or maggot. These larvæ are fed by the labouring wasps with a kind of honey, but very inferior to that of the common bee. The mothers attend to them with the greatest assiduity, and it is interesting to observe with what activity they visit the cells one after another, feeding each larya as they go along. When the larvæ are become large enough to fill their respective cells.
they close up the mouth by spinning a very fine silken web, pass into the chrysalis state, and, after a certain period, emerge in their perfect form. The males have no sting, and are not numerous; the females are but very few, but the neutral or labouring wasps abound, and compose nearly the whole of every swam. They lay up no store of honey for the winter, and most of them perish in the cold season. The few that survive lay the foundation of a new colony in the spring, which, by the month of July, is raised to a full and healthy swarm'. The remedies recommended at p. lvi, in the case of the bee, will be found equally efficacious in alleviating the pain occasioned by the sting of the wasp and the hornet. This last insect (v. crabro) is considerably larger than the common wasp, but, on a slight inspection, very similar in appearance and colour: it makes its nest in the trunks of hollow trees, and is not found in Scotland, though common enough south of the Tweed. Its sting is extremely painful.
Of the habits and economy of the bee (apis) we have, at various times, in our previous volumes, given many pleasing illustrations. The practical management of this insect, a subject which has been, till of late, but ill-understood, and yet of the last importance to those who reside in the country, and who, either from motives of amusement or of profit, wish to understand thoroughly the best method of keeping an apiary; such persons we beg to refer to the second edition of Mr. JENNINGS'S FAMILY CYCLOPÆDIA, article Bee, which we regret we have not space to transfer to our pages. This really useful work is not only a complete Code of Family Information, but is fertile of curious and original watter on subjects of Natural History.
* See Time's Telescope for 1820, Introduction, pp, xlii, xliii. *? Consult also · Huber on Bees, translated by Dr. J. R. Johnson, 12mo, 1808.-And here we must not omit to name, for the advantage