Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.
1 Fronds 1.5-8× as long as wide; angle of pouch 45-120°.
..2 Angle of pouch 70-120°; tract of elongated cells running between median line and the edge of lower wall of the pouch; area of air spaces within frond rarely longer than wide
..2 Angle of pouch 45-90°; tract of elongated cells running along or close to the edge of the lower wall of the pouch; area of air spaces within frond mostly longer than wide