Leaves pinnate-pinnatifid; petioles ca. 1/3 length of blades, winged, with light brown hairs, becoming glabrate. Sterile leaves elliptic to oblong, ca. 0.5--1 m; pinnae broadly oblong, lacking persistent tuft of hairs at base; ultimate segments with base truncate, margins entire, apex rounded. Fertile leaves with greatly reduced, sporangia-bearing medial pinnae that wither early, giving appearance of no middle pinnae (hence the vernacular name, interrupted fern). Sporangia greenish, turning dark brown. 2 n =44.
