Osmunda Osmunda, L.

1. O. regalis L. View in CoL , Sp. Pl. 1065 (1753).

Leaves 30-150 cm, densely tufted, only the upper (inner) ones of each year’s crop being fertile; sterile pinnules 3-5 x 1-1-5 cm, oblong, obtuse, sessile, sometimes pinnatifid at the base, otherwise usually entire (rarely serrulate), with conspicuous, dichotomous, non-anastomosing lateral veins. Sporangia confined to a few terminal pinnae of the fertile leaves, not occupying more than a quarter of the leaf; fertile pinnules c. 12 x 3 mm, pale green, rapidly turning brown. 2« = 44. Damp places; often on peat and with a calcifuge tendency. Widespread in W. Europe, extending very locally eastwards to E. Sweden, Poland and Turkey; much reduced by drainage in many areas. Al Az Be Br Bu Co Cr Cz Da Ga Ge Gr Hb He Ho Hs It Ju Lu No Po Sa Si Su Tu.

VII-XXII

These families have in the past usually all been placed in a single family, the Polypodiaceae . They have the following characters in common: Stems usually with hairs or scales. Leaves relatively large. Homosporous; sporangia with walls 1 cell thick; annulus present. Prothallus green,