Rhizome rather slender, sparingly branched, far-creeping, then high-climbing, 2-5 mm. diam., densely clad in dark brown linear-attenuate, squarrose paleae c. 5 mm. long; stipites distributed along rhizome. Stipes paleate; of juvenile plants slender, 1-2 cm. long; of adults stouter, up to 10 cm. long. Rhachis slender, paleate. Sterile laminae dimorphic, submembr., dark green, with numerous shortly stalked pinnae; costae ± paleate: (a) linear-lanceolate to narrow-oblong, obtuse to acuminate, 7-20 cm. × 15-30 mm., spreading; pinnae shortly stalked to subsessile, opp. to subopp., 5-15 × 3-10 mm., about oblong, coarsely dentate-serrate: (b) lanceolate-oblong, acuminate, pend., up to 35 × 5-15 cm.; pinnae more distant, subopp. to alt., oblong-lanceolate, acute to acuminate, up to 10 cm. × 15 mm., dentate-serrate, subfalcate; lower pinnae smaller, obtuse. Fertile laminae us. towards upper part of climbing portion of rhizome, ovate-oblong, up to 25 cm. long, slender to rather stout; pinnae spreading, rather distant: (a) narrow-linear to almost filiform, up to 5 cm. long: (b) linear, stouter, up to 15 cm. long. Sori covering whole of undersurface.

2n = 66 (±2)