| 1. | Leaves tufted ; stipes 15 - 30 cm long , densely scaly at base , glabrous above ; sterile lamina about 60 cm long and 20 cm wide , simply pinnate ; pinnae numerous , alternate or subopposite , linear - lanceolate , the largest about 12 cm long and 1 cm wide , base cordate , apex acuminate , margin finely toothed ; veins close , forking once or twice and forming areoles near the midrib ; fertile lamina similar to sterile ones , but somewhat reduced , about 8 cm long and 0 . 4 cm wide , lower surface almost entirely covered with sporangia 叶簇生;叶柄长15 - 30厘米,基部密被鳞片,向上近光滑;不育叶片长约60厘米,宽20厘米,一回羽状;羽片多数,互生或近对生,线状披针形,最长者长达12厘米,宽约1厘米,顶端长渐尖,基部心形,边缘有细密锯齿;叶脉1 - 2次分叉,近中脉形成网眼;能育叶与不育叶相似,但较小,长约8厘米,宽约0 . 4厘米,下部满布孢子囊。 |