| * Involucral bracts 8–10. | |
| Glabrous or nearly so. Leaves membranous, usually regularly denticulate | 1. E. prenanthoides. |
| ** Involucral bracts 10–14. | |
| Cottony or woolly. Leaves linear-oblong, lobed or pinnatifid | 2. E. arguta. |
| Scabrid with short white hairs. Leaves linear-oblong, lobed or pinnatifid | 3. E. scaberula. |
| White with cottony tomentum. Leaves linear-elongate, entire or minutely remotely toothed; margins revolute | 4. E. quadridentata. |
| Glabrous or nearly so. Leaves erect, lower oblong or linear-oblong, upper linear, entire or denticulate | 5. E. diversifolia. |
| Glabrous or nearly so. Leaves spreading, membranous, pinnatifid or pinnate with a large terminal segment | 6. E. glabrescens. |
1. E. prenanthoides, D.C. Prodr. vi. 296.—A tall erect annual or biennial herb 1–4 ft. high, simple or branched above, glabrous or slightly hairy. Leaves rather distant, 2–6 in. long or more, linear-oblong to lanceolate or linear-lanceolate, acuminate, lower petiolate, upper sessile with broad toothed auricles, membranous, regularly or irregularly closely and finely denticulate, rarely lobed. Corymbs very large, terminal, 6–12 in. across or more; pedicels slender, ¼–⅓ in. long. Heads quite glabrous, ¼ in. long; involucral bracts 8–10, narrow-linear, green with white margins. Florets 18–22; females more numerous than the hermaphrodite. Achenes linear-oblong, grooved, hairy, surmounted by a callous ring surrounding the base of the pappus.—Hook, f. Fl. Nov. Zel. i. 141; Handb. N.Z. Fl. 156; Benth. Fl. Austral. iii. 658; Kirk, Students' Fl. 333. Senecio prenanthoides, A. Rich. Sert. Astral. 96. S. heterophyllus, Col. in Trans. N.Z. Inst. xxvii. (1895) 389.
North and South Islands, Stewart Island, Chatham Island: Prom Ahipara and Mongonui southwards, but rare and local to the north of the Thames Valley. Sea-level to 3000 ft. October–January. Also in Australia and Tasmania.
2. E. arguta, D.C. Prodr. vi. 296.—A coarse erect annual herb 1–3 ft. high; stem stout, grooved, branched above, more or less cottony or woolly, rarely almost glabrous. Leaves 2–4 in. long, linear-oblong or lanceolate, acute or obtuse, lower usually contracted into a petiole, upper sessile with a broad toothed stem-clasping base, coriaceous, coarsely and irregularly toothed or lobed or pinnatifid, lobes sinuate-dentate, upper surface glabrous or cobwebby, beneath more or less clothed with loose white cottony tomentum. Corymbs terminal, dense; pedicels slender, cottony. Heads ¼ in. long; involucral bracts 12–14, usually with a few minute ones at the base, narrow linear-lanceolate, woolly below. Florets 30–40; females much the most numerous. Achenes linear-
