THOSE WHICH HAVE THE FRUITING PORTION IN GREENISH, BERRY-LIKE STRUCTURES AND NOT ON THE BACK OF FRONDS
A. FRUITING FRONDS WHOLLY FERTILE
(Fertile and sterile fronds entirely unlike)
1. Fruit in a one-sided spike in two ranks; plants very small; sterile fronds thread-like and tortuous.
Curly Grass. Schizaea.
2. Fruit in a club-shaped, brown or cinnamon-colored spike loaded with sporangia; fruit in early spring.
Cinnamon Fern. Osmunda cinnamomea.
3. Fruit in berry-like, greenish structures in a twice pinnate spike, which comes up much later than the broad and coarse pinnatifid sterile fronds.
Wet ground. Sensitive Fern. Onoclea.
4. Fruit in pod-like or necklace-like pinnae; fertile frond pinnate; sterile frond tall, pinnatifid; fruit late.
Ostrich Fern. Onoclea struthiopteris.
B. FRUITING FRONDS PARTLY STERILE
1. Fruiting portion in the middle of the frond; two to four pairs of fertile pinnae.
Interrupted Fern. Osmunda Claytoniana.
2. Fruiting portion at the apex of the frond. Sterile pinnae palmate; rachis twining.
Climbing Fern. Lygodium.
Sterile pinnae pinnate; fronds large, fertile portion green, turning brown, forming a panicle at the top.
Royal Fern. Osmunda regalis.
3. Fruiting portion seemingly on a separate stock a few inches above the sterile.
Sterile part an entire, ovate, green leaf near the middle; fertile part a spike.
Adder’s Tongue. Ophioglossum.
Sterile portion more or less divided; fruit in racemes or panicles, rarely in spikes.
Grape Ferns. Moonwort. Botrychium.
THOSE WHICH HAVE THE FRUITING PORTION ON THE BACK OR MARGIN OF FRONDS
A. INDUSIUM WANTING
1. Fruit-dots large, roundish; fronds evergreen. Rock species.
2. Fruit-dots small, roundish; fronds triangular.
Beech Ferns. Phegopteris.
3. Fruit in lines on the margin of the pinnules; under surface of the fronds covered with whitish powder.
Cloak Ferns. Notholaena.