Primary rachis-branches several times very unequally forked; at each fork the smaller branch unbranched and leafy throughout, commonly 20-25 cm long and 4-5 cm wide, with no accessory branch, the larger branch continuing almost the same straight line as the larger branch from the previous fork and bearing an accessory branch 12-15 cm long and 3.5 cm wide (this accessory branch almost opposite the simple leafy branch of the fork); ultimate fork formed by two normal leafy branches without accessory branches; irregularities from this basic scheme occasionally present; lamina-segments 3.5-4 mm wide, flat and rather rigid, separated by very narrow sinuses, apices often retuse; veins distinctly prominent on the upper surface; lower surface more or less glaucous, the costules when young rather densely covered with fine pale entangled woolly hairs, some similar hairs on veins; some dark redbrown, rigid, shining hairs, like those on resting apices, also at first present on costae and costules; sori as in D. linearis; spores trilete.
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