Glume a single scale-like bract with a flower in its axil. [Cyperaceæ], [567]

Glumes in pairs, of two sorts. [Gramineæ], [623]

Class III. CRYPTOGAMOUS ACROGENS. (See [p. 17.])

Subclass I. PTERIDOPHYTES: with woody fibres and vessels.

Spores of only one kind; spore-cases

Borne beneath shield-shaped scales in a terminal spike; stems naked, sheathed at the nodes. [Equisetaceæ], [675]

On the back or margin of fronds circinate in vernation. [Filices], [678]

Bivalvular, in special spikes or panicles; fronds erect in vernation, from short erect rootstocks. [Ophioglossaceæ], [693]

Solitary in the axils of leaves, 2–3-valved; low long-stemmed moss-like evergreens; leaves small, in 4–16 ranks. [Lycopodiaceæ], [695]

Spores of two kinds, large and small; spore-cases