Hymenophyllum .] 
EILICES. 
463 
valves semicircular. H. Boryanum, Willd. ; Bojer , Sort. Maur. 111. H. 
ArbuscuJa, Desv. 
Mauritius, in the damp forests of the Pouce range, etc. Seychelles, Ward ! 
Cosmopolitan in tropical and sub-tropical regions. 
7. H. hygrometricum, Desv.; Kuhn , Fil. Afr. 39. Stipe wiry, 
dark brown, 2-4 in. long, not at all winged. Frond oblong-deltoid, 
6-12 in. long, 2-4 in. broad, 3-4-pinnatifid, very elastic in texture and 
sensitive to moisture, so that it curls up when the air is dry, thinly 
covered with stellate hairs, the main rachis winged only at the top. 
Pinnae lanceolate-deltoid, cut away on the lower side at the base. 
Ultimate segments close, erecto-patent, entire, J— J- in. long, i Q - 
broad. Sori minute, many to a pinnule. Involucre immersed at the 
base; valves semicircular, conspicuously ciliated. II. elasticum, Dory; 
Hook, and Orev. Ic. Fil. t. 135 ; Hook, and Baker, Syn. Fil. 64. 
Mauritius, in woods of the Pouce range, etc. Seychelles, common in Mahe, 
Perville , Horne , 149 ! Also Bourbon and Madagascar. Very near H. hirtellum , Sw., 
of Tropical America. 
8. H. Tunbridgense, Smith ; Hook, and Baker , Syn. Fil. 67. 
Stipe wiry, |-1 in. long, not winged. Frond lanceolate, 2-3 in. long, 
under an inch broad, 2-3-pinnatifid, the main rachis winged only at the 
top. Pinnae ascending, close, cuneate-deltoid, the lower made up of 6-10 
distinctly-toothed segments, which are £ in. long by in. broad. 
Sori only one to a pinna, terminal on a short basal anterior lobe. In- 
volucre free ; valves obovate, distinctly toothed. 
Mauritius, Carmichael ! According to Bojer, H. unilaterale , Willd., which is a 
variety with entire involucral- valves, is found in the woods of Savanne and Grand 
Bassin, but we have not seen any specimen. Widely spread in Tropical and 
Temperate regions of the Old and New World. 
3. TRICHOMANES, Smith. 
Capsules, position of the sori, texture, and general habit just as in 
Hymenophyllum , but the involucre cylindrical or funnel-shaped, with a 
truncate mouth, or two shallow valves. Receptacle usually longer than 
in Hymenophyllum and protruded from the involucre. Distrib. All 
damp, tropical and warm temperate countries. Species 80. 
Fronds very small, entire or slightly lobed. 
Sorus solitary, terminal 1 . T. Barklianum. 
Sori several to a frond. 
Midrib distinct at the base only 2. T. cuspidatum. 
Midrib distinct nearly to the top 3. T. erosum. 
Fronds very small, digitately pinnatifid. 
Segments few, obscurely flabellate 4. T. digitatum. 
Segments many, distinctly flabellate. 
Vein of segments solitary . . . 
Veins of segments three .... 
5. T. FLABELLATUM. 
6. T. TRINERVE. 
