Manual of the New Zealand Flora.

6. Oplismenus, Beauv

6. Oplismenus, Beauv.

Weak, delicate grasses. Culms decumbent and often rooting at the base, branched, ascending above, leafy. Leaves thin, flat, broad, ovate to lanceolate. Spikelets 1-flowered, jointed on the pedicel, in little clusters on the branches of a simple panicle or spike. Glumes 4, the 3 outer membranous, empty or the 3rd with a rudimentary palea; the outer short, 3-nerved, with a long straight rigid awn; 2nd rather longer, awn short or almost wanting; 3rd the largest, 5-nerved, usually awnless; 4th or flowering glume rather shorter than the 3rd, lanceolate, firm, smooth, awnless, hardened in fruit. Palea coriaceous like the flowering glume. Stamens 3. Styles distinct. Grain oblong, enclosed within the hardened flowering glume and palea.

Species probably not more than 4 or 5, widely distributed in the warm regions of both hemispheres.

1. O. undulatifolius, Beauv. Agrost. 54.—Culms prostrate and rooting at the base, ascending above, slender, weak, sparingly branched, 6–18 in. long. Leaves 1–3 in. long by ¼–⅓ in. broad, rarely more, lanceolate, acuminate, flat, glabrous or sparsely pilose; sheaths and nodes more or less pilose. Spike slender, 2–4 in. long; rhachis glabrous or pilose with spreading hairs. Spikelets small, 1/12–⅛ in. long, in distant sessile clusters of 2–6 or the uppermost solitary, sometimes the lower clusters are produced into a short spike-like branch. Empty glumes 3, concave, membranous, nerved, pilose, the lower one with a stout rigid awn ⅕–½ in. long. Flowering glume pale, coriaceous, nerveless, shining.—O. setarius, Roem. and Schult. Syst. ii. 481; Benth. Fl. Austral. vii. 492. O. æmulus, Kunth, Rev. Gram. i. 44; Hook. f. Fl. Nov. Zel. i. 292. Orthopogon æmulus, R. Br. Prodr. 194. Panicum imbecille, Trin. Sp. Gram. Ic. ii. t. 191; Hook. f. Handb. N.Z. Fl. 323. Hekaterosachne elatior, Steud. Syn. Pl. Gram. 118. Kermadec Islands, North Island: Abundant throughout in shaded lowland stations. South Island: Recorded from Nelson (Travers) and Canterbury (Lyall), but I have seen no specimens. An abundant plant in all warm climates, and barely distinct from the widely diffused O. compositus, Beauv.