water-moss; a genus of the cryptogamia musci class. There are four species, all of them natives of Britain. They grow on the brinks of rivulets, and on the trunks of trees. The most remarkable is the antipyretica, with purple stalks. The Scandinavians line the inside of their chimneys with this moss, to defend them against the fire; for, contrary to the nature of all other moss, this is scarcely capable of burning.