Canker-Worm, a species of insects particularly destructive to corn, grass, and every other vegetable in which it can harbour. It has been erroneously supposed, that excessive and continual wet' weather will destroy them, but this is so far from being true, that an instance has occurred of their having been found buried six feet deep, in a firm soil.

These worms, every fourth year, become flies, when they deposit their spawn on the ground, and thus produce maggots. Soot has been strewed on the land infested with these vermin, and various other remedies have been tried, but without success ; except that practised in the county of Norfolk, where, some years since, the can-ker-worm was particularly pernicious. The expedient alluded to, ' is as follows: when they become flies, and are settled on the trees, especially those of oak, elm, and maple, they are shaken off, so as to drop on pack-sheets, or filters, spread under them for that pu-pose. If, in this manner, they are destroyed soon after their first appearance, when in the state of flies, and before they can do farther mischief by lodging on the ground, their numbers will be considerably diminished, and, in a few years, they will be almost wholly exterminated.