GRASS FAMILY 67 



49. BLEPHARIDACHNE Hack. 



Low branched perennials or biennials, with crowded involute leaves. Spike- 

 lets few in subcapitate panicles, 4-flowerod, the two lower flo\\ers neutral, the 

 U]>permost reduced to a stipitate villous 3-cleft awn. Empty glumes membranou;?, 

 carinate, 1-nerved, acute, ghibrou^, the first somewhat shorter. Lemma 3-nerved. 

 villous on the nerves, 3-lobed, with the middle loba longest; lubes in the neutral 

 flowers obtuse, in the perfect ones attenuate. Palet shorter, 2-koelpd, 2-nerv(Hl, 

 2-toothcd at the apex, imperfectl}' develo{>ed in the neutral flowers. Stamens 2. 

 Styles 2; stigmas elongated, minutely hairy. Grain free. [Eremochloc S. Wats., 

 not Eremochloa Buese.] 



1. B. Kingii (S. Wats.) Hack. Stems 3-7 cm. high, glabrous; leaf-blades 

 1-2 cm. long, rigid, revolute-setaceous, pungent; emj>ty ghnnes 7 mm. long, 

 acuminate, purplish; lemma of the neutral flovvers 4 mm. long, very villous at 

 the base; that of the perfect flower glabrous at the base, awned; rudiment 3- 

 awned. Dry barren foot-hills: Nev.— LT'tah — Ariz. Son, M}'. 



50, TRIPLASIS Beauv. Saxd-grass. 



Tufted perennials. Panicles in our species narrow. Spikelet short-pedic*^l- 

 late, 2-6-flowered, the flowers perfect or the uppermost staminate, the rachis 

 glabrous, articulate between the flowers. Empty glumes keeled, 3-nerved, 

 shorter than the lemma. Lemma dorsally rounded at the base, 3-nerv^ed, 

 deeply 2-lobed at the apex, with an awn arising between the lobes. Palet shorter, 

 with 2 ciliate keels, compressed. Styles short; stigmas plumose. 



1. T. purpurea (Walt.) Chapm. Tufted perennial (?); stem 3-10 dm. 

 high, erect, prostrate or decumbent, branched below; leaf-blades 1-6 cm. long, 

 2 mm. wide, rigid, scabrous, sparsely ciliate; panicle 2-7 cm. long; spikelets 2-5- 

 flowered, 5-8 mm. long; lemma oblong, 2-lobed at the apex, with erose-truncate 

 lobes; midvein excurrent in a short point. Sandj^ places: Me.— Fla. — -Tex. — 

 N.M.— Neb. Plain. Au-S. 



51. DASYOCHLOA Willd. 



Stoloniferous perennials. Inflorescence densely paniculate. Spikelets flat, 

 5-10-flowered; flowers perfect. Empty glumes 2, membranous, ovate, nearly 

 equal. Lemma oblong, more or less pubescent, at least on the veins, cleft to 

 the middle, with an awn between the lobes, 3-nerved. Palet broad, prominently 

 2-keeled. Styles short, distinct; stigmas phimose. 



1. D. pulchella (ILB.K.) Willd. Densely tufted; stem 3-10 cm. high, 

 fasciculately branched; leaf-blades 1-3 cm. long, about 1 mm. wide, involute, 

 striate, curved, scabrous; inflorescence small and compact; spikelets 5-10- 

 flowered, 5-8 mm. long; empt}' glumes white, lanceolate, 5-7 mm. long, acumin- 

 ate; lemma 4-6 mm. long, oblong, cleft to the middle. Triodia pulchelkt H.B.K. 

 Hills and plains: Tex. — w Wj'o. ---Calif.; Mex. Son, Ap-O. 



52, ERIONEURON Xash. 



Tufted, low perennials. Panicles small, dense, subcapitate. Leaves thick, 

 ydth thickened white margins. Spikelets several-flowered. Empty glumes 

 narrow, acuminate. Lemma broad, 3-nerved, pubescent on the nerves below, 

 with long silky white hairs, acuminate at the apex, entire or shghtly 2-toothed, 

 the terminal awTi rising between the minute teeth. Style short. 



1. E, pilosum (Buckley) Xash. Stem 0.5-3 dm. high, leafy mostly at the 

 base; leaf -sheath pilose-ciliate at the summit; blades erect, thick, folded, papillose- 

 ciliate, 2-8 cm. long; spikelets 3-S, crowded, 1-1.5 cm. long; lemma 5.5-6 mm. 

 long, acuminate, entire or slightly toothed at the apex; awn l-l'.S mm. long. 

 Tricuspis acuminata Munro. Triodia acuminata Vasey. Dry gravelly or sandy 

 soil: Kans. — Nev. — Ariz. — Tex. Son. — Submont. Ap-0. 



53. TRIDENS R. & S. 



Perennials with rootstocks, ours tufted. Panicles open, or in ours narrow, 

 sometimes spike-like. Spikelets 3-many-flowered, the flowers perfect, or the 



