I

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)

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1.  Fruit in a one-sided spike in two ranks; plants very small; sterile fronds thread-like and tortuous.

Curly Grass. Schizaea.

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2.  Fruit in a club-shaped, brown or cinnamon-colored spike loaded with sporangia; fruit in early spring.

Cinnamon Fern. Osmunda cinnamomea.

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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.

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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

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1.  Fruiting portion in the middle of the frond; two to four pairs of fertile pinnae.

Interrupted Fern. Osmunda Claytoniana.

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2.  Fruiting portion at the apex of the frond.  Sterile pinnae palmate; rachis twining.

Climbing Fern. Lygodium.

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Sterile pinnae pinnate; fronds large, fertile portion green, turning brown, forming a panicle at the top.

Royal Fern. Osmunda regalis.

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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.

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Sterile portion more or less divided; fruit in racemes or panicles, rarely in spikes.

Grape Ferns.  Moonwort. Botrychium.

II

THOSE WHICH HAVE THE FRUITING PORTION ON THE BACK OR MARGIN OF FRONDS

A. INDUSIUM WANTING

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1.  Fruit-dots large, roundish; fronds evergreen.  Rock species.

Polypody. Polypodium.

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2.  Fruit-dots small, roundish; fronds triangular.

Beech Ferns. Phegopteris.

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3.  Fruit in lines on the margin of the pinnules; under surface of the fronds covered with whitish powder.

Cloak Ferns. Notholaena.

B. INDUSIUM PRESENT