CYSTOPTERIS (Bladder Ferns)
Delicate rock or wood ferns, with 2-3 pinnate fronds and round fruit-dots; indusium hood-like, attached by a broad base to the inner side, soon thrown back or withering away; sporangia as above.
ASPIDIUM (Shield Ferns)
Ferns with 1-3 pinnate fronds and round fruit-dots; indusium more or less flat, fixed by its depressed centre; sporangia as above.
PHEGOPTERIS (Beech Ferns)
Medium-sized or small ferns, with 2-3 pinnatifid or ternate leaves, and small, round, uncovered fruit-dots; sporangia as above.
WOODWARDIA (Chain Ferns)
Large and rather coarse ferns of swamps or wet woods, fronds pinnate or nearly twice-pinnate; fruit-dots oblong or linear, sunk in cavities of the leaf and arranged in chain-like rows; indusium lid-like, somewhat leathery, fixed by its outer margin to a veinlet; veins more or less reticulated; sporangia as above.