4 FILICES. 
Suborder VIi. Mararrracearn. Sori distinct, dorsal. Sporangia sessile, without any 
ring, coriaceous, splitting vertically or opening by a pore at the apex, usually cohering 
mm concrete masses called synangia. 
Rhizome large, tuberous. Fronds large, 2-3-pinnate .. .. 38 MARATTIA, 
Suborder VIII, OpxioGLOssacEAE. Sporangia globose, coriaceous, sessile, without any 
ring, dehiscing by a transverse or vertical slit, crowded on a linear spike or on the 
branches of a panicle. Fronds not circinate in vernaiion. 
Sterile frond simple and entire. Sporangia on a linear spike .. 39. OpHTOGLOSsUM. 
Sterile frond pinnate or 2—4-pinnate. Sporangia on the linear 
branches of a panicle 
; 
40. BotTrRycHIUM. 
1. HYMENOPHYLLUM Linn. 
Usually small and sometimes minute ferns. Rhizome slender, creeping, 
often much branched and matted. Fronds simple or more generally 
compound, delicately membranous, often pellucid, usually of a single 
layer of cells; segments entire or toothed at the margin, with a stout 
central costa. Sori marginal, terminal or lateral, more or less immersed 
in the frond or quite free, always terminating a vein or costa. Indusium 
cup-shaped, more or less deeply 2-lipped or 2-valved, sometimes to the 
base, of almost the same texture as the frond, margins of the lips entire 
or toothed or fringed. Receptacle linear or oblong, not exserted beyond 
the indusium. Sporangia sessile or nearly so, depressed, surrounded by 
a broad complete horizontal ring, bursting transversely. 
One of the most beautiful of the genera of ferns, almost wholly confined to shaded 
localities, and remarkable for the filmy texture of the frond, a peculiarity which it 
shares with T'richomanes and Leptopieris, Species about 150, widely distributed in 
tropical climates and in the South Temperate Zone, especially abundant in New 
Zealand, rare in the North Temperate Zone. Of the 20 species found in New Zealand, 
7 or perhaps 8 are endemic, the remainder are for the most part widely dispersed. 
A, EKuhymenophyllum. Margin of the frond entire. 
* Fronds glabrous; or, if hairs are present, they are confined to the stipes, 
rhachis, and costae. 
tT Rhachis winged throughout; wing often decurrent down the stipes, some- 
times to the base. 
Fronds “1-4in., pendulous, flaccid, 2-pinnatifid. Stipes 
capillary ; rhachis often wingless below. Sori large, terminal, 
immersed ; indusium orbicular .. a wt .. IL. A. rarum. 
Fronds 2-9in., olive-green, 3-pinnatifid, sometimes with 
scattered hairs on the rhachis and stipes. Sori terminating 
short lateral segments, free ; indusium broadly ovate .. 2. H. sanguinolentum. 
Fronds 2-6in., brownish-green, 3-4-pinnatifid; segments 
narrow, crowded. Stipes, rhachis, and costae usually villous. 
Sori numerous, terminal, free ; indusium broadly ovate .. 3. H. villoswm. 
Fronds 3-9 in., triangular. Rhachis with a broad much-crisped 
wing decurrent aimost to the base of the stipes. Sori 
terminal, free ; indusium orbicular 3) 4 .. 4. H. australe. 
Fronds 2—3in., linear-oblong, dull dark-green. Rhachis with 
a broad flat wing decurrent almost to the base of the stipes. 
Sori termina!, free ; indusium ovate, margins often jagged .. 5. H. atrovirens. 
Rhizome short, bristly. Fronds 9-20 in., ovate-lanceolate, pale- 
green. KRhachis with a narrow flat wing decurrent down the 
stipes. Sori terminal, free; indusium orbicular .. .. 6. H. pulcherrimum. 
Rhizome long, glabrous. Fronds 9-20 in., ovate-lanceolate ; 
segments broad, flat. Rhachis with a narrow flat wing 
decurrent along the stipes. Sori terminal, immersed ; 
indusium orbicular + fe <4 *. .. 7. H. dilatatum ; 
