The fern flora of Canada

Fronds all leafy ; indusium a small, thin, pointed, scoop-shaped scale or memhrane, attached at its base to a \ einule, and at first hiding the spore-cases, (tig.0, a,nat.size, b, enlarged).(Small ferns, somewhat tufted.)VI.Adiantum.Fronds all leafy, unusually thin and papery ; sori borne on special involucres formed by upper portions of the margins of the leaflets of the frond folded back, the spore cases on their under side.(A rather small fern with aggregated but not tufted fronds.)VII.OlieilantllSS.Fronds all somewhat leafy, woolly or chaffy ; involucres formed of reflexed portions of the frond-margin, spore cases on the frond itself.(Small ferns.) VIII.PteriS.Fronds all leafy, hard, much-divided ; involucre parallel with and under reflexed margin of pinnule, spore cases forming a continuous marginal line, (fig.6.) (A very tall fern, fronds rising singly from a running rhizome.)IX.PellSBa.Fronds all leafy, hard, rather dull-green, not much divided, fertile ones with narrower divisions ; the reflected margins of the pinna?forming indusia ; spore cases crowded in a continuous line.(Small ferns, not tufted.