| With the disappearance of the indusia the sori tend to spread over the whole surface of the back of the frond. |
| The sori are quite naked, no indusia being present at any time. |
| Sporangia near or on the margin of the segments, the reflexed portions of which serve as indusia. |
| The indusia of the areoles next the midrib are also often bent at an angle, and the two portions plainly united. |
| The leaf margins themselves are often reflexed to form false indusia that protect the sori. |
| The sori have indusia, but this is hidden by the margin of the pinnules, which are recurved. |
