fringe moss

fringe moss, any of the plants of the genus Grimmia (subclass Bryidae), which includes more than 100 species distributed throughout the world, primarily on rocks or stone walls. A few species grow on roofs or in streams; G. maritima forms cushions up to four centimetres (1 1/2 inches) tall on rocks along seashores. Nearly 50 species of Grimmia are native to North America, and about 30 are found in Great Britain. Most fringe mosses are...