rhachis glabrous or pilose with spreading hairs. Spikelets small, 112–18 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.
7. CENCHRUS, Linn.
Annual or perennial grasses, usually tall. Leaves flat, flaccid. Spikelets narrow, with a single terminal hermaphrodite flower with or without a male flower below it, enclosed 1–4 together in an ovoid or globose involucre of numerous bristles or spines, the inner of which are broad and flattened, connate at the base and hardened in fruit; the involucres sessile in a terminal spike or raceme, and deciduous with the spikelets. Glumes 4; the outer much the smallest, sometimes minute, empty; 2nd equalling the 3rd or a little shorter, empty; 3rd usually containing a palea and sometimes 3 stamens; 4th or flowering glume rather shorter than the 3rd and more rigid. Stamens 3. Styles often connate at the base. Grain enclosed in the flowering glume and palea, free from them.
Species about 12, in the warm regions of both hemispheres and in temperate North America.
1. C. calyculatus, Cav. Ic. v. 39, t. 463.—Culms tufted, tall, stout, glabrous, 2–4 ft. high or more. Leaves long, linear-lanceolate, acuminate, ⅓–⅔ in. broad, flat, glabrous, scaberulous on the margins and veins above; sheaths long, rather lax; ligule split into numerous fine erect bristles. Spike 5–10 in. long by ½ in. broad, stout, dense; rhachis angular, pubescent. Involucres about ⅓ in. long, sessile or very shortly pedicelled, spreading or at length deflexed, broadly ovoid; inner bristles 8–12, connate at the base, compressed, unequal in length, sometimes one much longer than the rest, lower ⅔ plumose with soft spreading hairs, upper ⅓ rough and scabrous; outer bristles numerous, much shorter, spreading, subulate, scabrous throughout. Spikelets 1 or 2 within the involucres; outer empty glume half the length of the 2nd, ovate, acute, 1-nerved; 2nd
