Osmunda

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Osmunda (family Osmundaceae) A genus of large ferns with massive, erect rhizomes, and bi-pinnate leaves. The sporangia are borne mostly on the upper margins of specialized pinnules without lamina or chlorophyll, and are massive, short-stalked structures, cultivated as ornamentals (royal ferns). There are some 10 species, cosmopolitan in distribution but absent from Australasia.