1 | Fronds simply pinnate, veins free, pinnae numerous, spreading, jointed to rachis. |
1' | Fronds otherwise. |
2 | Pinnae or lobes elongate, bearing many sori, each at the end of a single vein; lamina rather thick. |
2' | Pinnae or lobes, if elongate, bearing a sorus connecting the ends of several veins; lamina thinner. |
3 | Fronds flnely divided, the ultimate divisions small and connected with each other by wings; sori solitary at apices of ultimate divisions |
3' | Fronds variously branched; leaflets distinct, each with several sori or a more or less continuous marginal sorus |