668 GENERA OF FERNS. 
character (besides being arboreous) that distinguishes it from 
Polypodium ; while even that character is iis tenable in 
Gymnosphera aculeata, a native of Trinidad. 
124. TRICHOPTERIS, Presl. 
Veins pinnately-forked , venules simple, direct, free, their 
apices clavate. Sori medial, trichophorous, laterally con- 
fluent, forming a transverse compound, linear sorus. Recep- 
tacle oblong, elevated. 
Fronds bipinnate; pinnules lanceolate, entire, serrate towards 
their apex, coriaceous, articulated wilh the rachis. 
Species. 1. T. excelsa, Presl. 2. T. elegans, ` Presl. (Also- 
phila, Mart.) 
Iilust. Hook. et Bauer, Ze fil. t. 34. Schott, gen. fil. t. 5. 
Mart. Crypt. Bras. t. 37, 3 
Obs. Very distinct in den from Alsophila, though difficult 
to be distinguished by any peculiarity in the technical cha- 
racter of Ce sori. 
125. Meraxya, Presl. 
(Polypodii sp. Willd. Hook. Amphidesmium Schott, in obs.) 
Veins simple, or rarely forked, parallel, "direct, free. Sort 
medial (often two on the same vein) trichophorous, irregular. 
Receptacle slightly elevated. 
Fronds coriaceous, pinnate; pinne linear-lanceolate, 6 to 8 
inches long, apex attenuated and serrate. Veins prominent, 
usually simple or forked close to the midrib. 
Species. 1. M. rostrata (Willd) 2. M. Parkeri, J. Sm. 
. (Polypodium, Hook. et Grev.) 
Illust. Hook. gen. fil. t. 42. B.Hook. et Grev. ic. fil. t. 232. 
Mart. Crypt. Brasil. t. 39. 
Obs. This genus differs from all the preceding, in being 
simply pinnate, and is remarkable for being the only fern 
that produces more than one sorus on the same branch of the 
veins. 
(To be continued.) 
