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attacked by birds; but when it is required, this hard texture is softened by the moth, when emerging from its imprisonment, by.a quantity of fluid, with which it is furnished for that purpose. Some few of the larva live in society, under a :kind of web, formed by their joint industry. The caterpillar of the Brown-tailed Moth furnishes an example of this kind: as soon as the young caterpillars are hatched, they begin a small web, and feed on the foliage of the tree, arranging themselves, with great regularity in rows, and at first devour only the upper parts of the leaves, retiring in the evening to their web. In about three weeks they cast their skin, and enlarge their web from time to time, forming it on all 'sides as strong as possible. Under this coveriig they remain the whole winter in a state of torpidity, till, being revived by the genial season of spring, they again issue forth. Having become stronger, they devour the whole substance of the leaves, without distinction of parts, and sometimes are so numerous, as to cause great destruction to the verdure of the country.

The most valuable of all moths, is the Silk
worm, with whose metamorphosis and figure
you are `veil acquainted. The art of convert
ing its silk into use, is said to have been first
in vented