Digitaria Haller, Hist. Stirp. Helv. 2: 244. 1768; Bor, Grasses Burma, Ceyl. Ind. Pak. 292. 1960; Sharma & Khosla, Grasses Punj. and Chandigarh 122. 1989; Chen & Phillips, Fl. China @ eFloras.org 22: 539; Fl. Pak. @ eFloras.org p. 216.

Annuals or perennials. Culms erect or decumbent, occasionally stoloniferous. Leaf blades linear to narrowly lanceolate, flat; ligule membranous, glabrous or ciliolate. Inflorescence of few to many racemes, digitately arranged or on a short axis, rarely the racemes solitary. Spikelets in groups of 1-5, arranged into 2 rows along a more or less flat or triquetrous rachis, with or without wing. Spikelets sessile or pedicellate, pedicels terete or triquetrous usually smooth or scaberulous. Spikelets 2-flowered, lanceolate to oblong-elliptic, flattened on front, convex on back. Glumes unequal; lower or abaxial reduced or absent, generally represented by small scale-like structure; upper or adaxial, as long as or shorter than spikelets, 3-nerved, sometimes a small nerved or nevertheless scale. Lower floret barren, its lemma (lower lemma) 5-many-nerved, +/- equal to spikelet, usually hairy, typically with the hairs forming stripes between the 1st and 2nd lateral nerves and along the margin; palea (lower palea) very small or absent. Upper floret bisexual, pallid to black, apex subacute to acuminate; its lemma (upper lemma) cartilaginous, 1-3-nerved, with its hyaline margins enfolding and similar in texture and as long as the lemma. Stamens 3. Stigmas 2. Caryopsis oblong.

262 species

Digitaria bicornis (Lam.) Roem. & Schult., Syst. Veg., ed. 15 [bis]. 2: 470. 1817; Bor, Grasses Burma, Ceyl. Ind. Pak. 299. 1960; Veldkamp in Blumea 21: 30. 1973; Sharma & Khosla, Grasses Punj. and Chandigarh 125. 1989; Singh & Sharma, Fl. Chamba Dist. 775. 2006; Fl. China @ eFloras.org 22: 543; Paspalum bicorne Lam., Tab. Encycl. Meth. Bot.1: 176. 1791; Digitaria biformis Willd., Enum. Pl. Hort. Berol. 92. 1809; Bor, Grasses Burma, Ceyl. Ind. Pak. 299. 1960; Panicum bicorne (Lam.) Kunth, Rev. Gramin. 1: 33. 1829.

An annual grass with culms ascending from a geniculate or prostrate base up to 75 cm long. Leaf blades linear or linear-lanceolate, 3-11 cm x 3-7 mm; often conspicuously sinuate on one margin, glabrous usually scabrid on both surfaces, rarely sparsely pilose; leaf sheaths striate, lower ones loose, hairy at mouth; ligule membranous, truncate, ca. 2 mm long. Inflorescence of 2-5 racemes, stout, stiffy, erect, digitate or subdigitate, 5-12 cm long. Spikelets 3-3.5 cm long, paired, imbricate, arranged into 2 rows along a rachis; rachis triquetrous, ca. 1 mm wide, winged, angles scaberulous; spikelet pairs heteromorphous: lower one sessile or subsessile, upper one pedicelled.

SESSILE OR SUBSESSILE SPIKELET: 2-flowered, glabrous, narrow elliptic. Glumes unequal; lower glume a minute triangular scale, obtuse; upper glume shorter than the length of spikelet, 2-2.5 mm long, linear-lanceolate, acute, 3-nerved, hairy along margin. Lower floret barren, its lemma (lower lemma) as long as spikelet, 7-nerved (5 nerves prominent from front), membranous, glabrous, margin ciliate. Upper floret bisexual, its lemma (upper lemma) ca. 2.5 mm long, cartilaginous, elliptic-lanceolate, acute, glabrous, margins enfolding and concealing most of the palea. Palea (upper palea) similar in texture and as long as upper lemma. Stamens 3; anthers oblong, +/- 1 mm long. Stigmas 2, plumose. Caryopsis oblong.

PEDICELLED SPIKELETS: Similar in shape and size to subsessile spikelets. Upper glume hairy and bristly. Lower lemma as long as spikelet, 7-nerved, lemma with wider glabrous interspaces on either side of mid nerve, lateral nerves crowded near margins; rows of silky hairs between lateral nerves, also at margins, usually also setose, the hairs spreading halo-like at maturity.

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