This genus was re-described in Blumea 19 (1971) 34. It comprises the Thelypteroid ferns of the Old World which have basal pinnae unreduced, all pinnae crenate to shallowly lobed, with anastomosing veins; it also includes a few species with simple entire lamina. The present account is based on a study of type material of almost all species, and of all specimens in the herbaria at Kew, British Museum, Leiden, Florence, Geneva, Paris, Bogor, Singapore, Lae, and the U.S. National Herbarium. Thanks are expressed to the Directors and staff of these and other herbaria for their cooperation.