Prate XLIX. в. 
WILSONS, or THE UNILATERAL FILM FERN 
(HIYMENOPHYLLUM UNILATERALE). 
HYMENOPHYLLUM, Smith. 
Clusters of Spore-eases enclosed within extra-marginal two-valved sub-urecolate 
tho samo texture as the frond. 
ile around the columnar receptacle, bursting verti- 
cally. Receptacles (extra-marginal extensions of the veins) free, and included 
within tho involueres, sub-l Veins disunited at their extremities, simple 
or forked, 
Н. unttatenate: fronds pellucido-membranaceous, pinnate, oblong-elongate or linear 
Шу deeurrent forming 
pinna» decurved, sub-unilateral, digitately pinnatifd, sligl 
art of the rachis ; segments lincar, undivided, or 
а narrow wing in the upper 
involueres axillary, solitary, stalked, ovate, inflated, 
bifid, spinulosely serrate 
the valves entire 
EXPLANATION OF THE PLATE. 
g, branched, and forming dense entangled masses 
Rhizome rigid, filiform, dark brown, creeping, 
few hair-like scales about the bases of tho fronds, Fibres slender, downy. 
Dearin 
i frond, often less ; distant 
ink 
Stipes slender, wiry, terete, varying 
Stip У 
‚al on the rhizome, and adherent to 
Vernation circinate. 
