Page:Manual of the New Zealand Flora.djvu/389

Siegesbeckia.]

Annual or perennial usually erect herbs. Leaves opposite, toothed or incised or pinnately divided. Heads corymbosely panicled or subsolitary, on long peduncles, heterogamous and radiate, or homogamous and discoid. Involucre campanulate or hemispherical; bracts in about 2 series, connate at the base, the outer herbaceous, the inner membranous. Receptacle flat or convex, paleaceous. Ray-florets when present female or neuter; ligule white or yellow, spreading. Disc-florets hermaphrodite, tubular, 5-toothed. Anthers usually obtuse at the base. Style-branches of the hermaphrodite florets hairy above, with a long or short subulate point. Achene broad and compressed or slender and tetragonous, often narrowed at the tip. Pappus of 2–4 rigid retrorsely hispid bristles.

1. B. pilosa, ''Linn. Sp. Plant.'' 832.—An erect glabrous or pubescent herb 1–3 ft. high; branches angular, grooved. Leaves very variable, simple or pinnate; segments 3 or 5, stalked, ¾–2 in. long, ovate or ovate-lanceolate, acute or acuminate, serrate or rarely lobed, thin and membranous. Heads few, terminal on long slender peduncles, yellow, ⅓–½ in. diam.; involucral bracts about ¼ in. long. Ray-florets few and short, often entirely wanting. Achenes black, slender, 4-angled, striate, crowned with 2 or 4 barbed awns.—''A. Rich. Fl. Nouv. Zel. 235; A. Cunn. Precur. n. 442; Raoul, Choix, 45; Hook. f. Handb. N.Z. Fl. 138; Benth. Fl. Austral.'' iii. 543; Kirk, Students' Fl. 318. B. aurantiacus. ''Col. in Trans. N.Z. Inst.'' xxvii. (1895) 388.

Creeping or tufted perennial or annual herbs, usually of small size, often aromatic. Leaves alternate, pinnatifid or pinnatisect, rarely entire or toothed. Heads small, peduncled, heterogamous and discoid or rarely homogamous through the suppression of the female florets, sometimes diœcious. Involucre hemispheric or campanulate; bracts in about 2 series, membranous or herbaceous; margins often scarious. Receptacle flat or convex or conical,