A genus of medium-sized to large mosses, in which the stems are irregularly to sub-pinnately branched. The leaves are triangular, tapering from the base to a long point at the tip; a single nerve extends about three-quarters of the way up each leaf. It is a small genus, with about 11 species, found in Europe, Asia, Africa, and America. H. sericeum (formerly Camptothecium sericeum) is a prostrate, creeping plant which forms extensive mats on walls, rocks, trees, roofs, etc.; it is yellowish-green to brown, with a characteristic silky sheen especially noticeable when the plant is dry. H. lutescens (formerly C. lutescens) is not prostrate; it forms loose tufts, is yellowish-green in colour, and is found chiefly on calcareous soil.
Subjects: Plant Sciences and Forestry.