Erect grasses with flat leaf-blades and racemose inflorescence. Spikelets 5-14-flowered; flowers perfect, or the upper staminate. Two lower scales empty, unequal, thin-membranous, 1-nerved, or the second imperfectly 3-nerved; flowering scales longer, membranous, 7-nerved, the middle nerve excurrent as a short point or awn. Palet scarcely shorter than the scale, 2-keeled, the keels winged or appendaged. Stamens 3. Styles short. Stigmas plumose. Grain free, enclosed in the scale and palet. [Greek, side-beard, from the appendages to the palets.]

Three known species, the following arctic, the others Californian. Type species: Pleuropogon Sabinii R. Br.

86 Pleuropogon R Br App Parry s Voy 289 1824 595

1. Pleuropogon Sabinii R. Br. Sabine's Pleuropogon

Fig. 595

P. Sabinii R. Br. App. Parry's Voy. 289. 1824.

Smooth, culms 6' or less tall, erect, simple, glabrous. Sheaths one or two; ligule 1" long; blades 1/4'-1' long, erect, glabrous; raceme 1-2' in length; spikelets 3-6, 5-8-flowered, about 5" long, on spreading or reflexed pedicels 1" or less in length; lower scales smooth, the first acute, shorter than the obtuse second; flowering scales oblong, 2"-2 1/2" long, erose-truncate at the scarious summit, scabrous, the midnerve sometimes excurrent as a short point; palet slightly shorter than the scale, truncate and somewhat 2-toothed at the apex, bearing an awn-like appendage on each keel near the middle.

Arctic regions of both the Old World and the New. Summer.