Chapter 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)

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

Curly Grass. _Schizæa_.

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 pinnátifid sterile fronds.

Wet ground. Sensitive Fern. _Onoclea_.

4. Fruit in pod-like or necklace-like pinnæ; fertile frond pinnate; sterile frond tall, pinnátifid; 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 pinnæ.

Interrupted Fern. _Osmunda Claytoniana_.

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

Climbing Fern. _Lygodium_.

Sterile pinnæ 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_.