Blechnum L.

Coenosori in a continuous or almost continuous line on each side of the midrib covering the vascular commissures, having a membranous indusium opening inwards towards the costa. Veins of the sterile fronds free Blechnum
Fertile and sterile fronds similar; the fertile pinnae or frond-segments slightly narrower to one-third of the width of the sterile
Sterile frond-segments attached by their broad bases. Plants up to 110 cm high. Widespread. RF; margins of RF; open forests, on hillsides often amongst rocks. Gristle Fern Blechnum cartilagineum
Sterile frond-segments (pinnae) very shortly and distinctly stalked in the greater part of the frond or in the lower third