Perennial, compactly cæspitose, with intravaginal innovations from a short oblique rhizome, with stout root-fibres, not much over 1 1/2 ft. high. Culms compressed below, about 2-noded, erect, simple, glabrous except upwards, smooth. Leaf-sheaths of innovations at the base of the culms strongly compressed and keeled, very firm and long-persistent, up to 5 in. long and 1/4 to almost 1/2 in. wide (when seen from the side), glabrous and very smooth below, more or less hairy to subvillous upwards, at least when young; ligules reduced to a ciliate rim; blades linear, very acute, passing almost imperceptibly into the sheath, tightly folded or opening out upwards, up to 6 or sometimes 8 in. long, 1–3 lin. wide (unfolded), very firm, rigid, pale green or subglaucous, turning russet, almost villous at the junction of the blade, otherwise sparingly hairy or at length quite glabrous, smooth, margins scaberulous, midrib compressed downwards into a narrow acute keel, up to almost 1 lin. high, lateral nerves numerous, close, slightly raised; subtending leaf with a spathaceous subherbaceous early convolute sheath, up to 5 lin. long, and a short herbaceous blade. Peduncle stoutly filiform, hairy above with truncate bearded tips. Inflorescence a true more or less fastigiate panicle, 2–3 in. long; common axis up to 1 in. long, filiform, grey, hairy to villous; basal branches 2-nate to sub-3-nate, all the branches representing sessile, or the lowest bare-based (base up to 5 lin. long) racemes. Racemes about 5, very lax and flexuous, rich purple, 1–2 in. long; joints and pedicels very similar, filiform, about 2 1/2 lin. long, equally and shortly ciliate on both sides, cilia silvery, 1/2– 3/4 lin. long. Sessile spikelets normally linear and acuminate in front view, 3–3 1/2 lin. long, glabrous, rich or brownish violet; callus short, obtuse, bearded from the very base, beard silvery, 1/2– 3/4 lin. long. Glumes equal, the lower chartaceous, more or less concave, minutely 2-denticulate, keels acute and very finely scaberulous upwards, intracarinal nerves 1 or 2, faint, very slightly raised in the upper part; upper narrowly boat-shaped, very gently curved on the back, subchartaceous, 3-nerved, mucronulate, ciliolate. Lower floret reduced to a narrow oblong obtuse 2-nerved sub-eciliate valve, 2 1/2 lin. long. Upper floret functionally ♀: valve reduced to a chartaceous sublinear stipe, produced into delicate hairlike lobes, its body 1 3/4 lin. long, glabrous; awn about 5 lin. long, kneed at and twisted below the middle, the bristle usually flexuous and often reflexed; valvule 0. Anthers reduced to very minute empty 2-lobed bodies on short hair-like filaments. Pedicelled spikelet lanceolate, acute, 3 1/2–4 1/2 lin. long, violet, glabrous; glumes equal, submembranous, very similar, 5-nerved, with the middle nerve more marked and distant from the paired marginal nerves; valve of lower floret oblanceolate, 1-nerved, sub-eciliate, hyaline, as long as the glumes; of upper floret very narrow, linear, up to 1 1/2 lin. long, nerveless or obscurely 1-nerved or 0; anthers 2 1/2 lin. long; pistil 0.