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Hypnum (order Hypnobryales) A genus of mosses in which the stems are creeping to erect, and almost unbranched to closely pinnately branched; branch leaves are similar in shape to the stem leaves, but are smaller. The capsule is erect to horizontal, and ovoid to cylindrical; and is borne on a long, reddish seta. Hypnum is a cosmopolitan genus, with about 220 species. H. cupressiforme is one of the commonest British mosses. It is very variable in form, with a number of distinct varieties. The typical form is a prostrate moss with pinnate branching; the leaves are concave, curved, and overlap one another to give some resemblance to a cypress branchlet. The leaves are nerveless and the leaf cells are long and narrow. The capsule is cylindrical and curved and has a beaked lid. The leaves are characteristically all turned downwards, especially at branch tips, although this character is lacking in some of the varieties. H. cupressiforme is found in a very wide range of habitats.