About 150 species of ferns with a cosmopolitan distribution. They are more or less clump-forming. with thickish to stout scaly rhizomes and bi to trip-innate (occasionally simply pinnate) leaves. The kidney or buckler-shaped sori are prominent on the pinnules, being borne in two rows midway between the midribs and margins.
None of the hardy species is small enough for the rock garden, but a few have produced small mutant cultivars which are suitable for shaded sites and as specimens for the alpine house. Well drained humus-rich soil which is moist but reasonably well drained, and full to partial shade. Propagation by division in late winter, or spores in spring.