involucral bracts numerous, ovate or lanceolate. Calyx-teeth obsolete. Petals oblong, acute, with a short incurved tip. Fruit oblong or linear-oblong, usually tapering to the apex, slightly compressed laterally; carpels subterete, with 5 equal obtuse ribs, the 2 lateral ones close to the commissure. Vittæ 1 in each furrow and 2 on the commissural face. Seed nearly terete, but grooved on the commissural side.
A genus of 5 or 6 species, all of which are natives of America, from Mexico to the Falkland Islands, one of them extending to Australia and New Zealand.
1. O. andicola, Endl. Gen. Plant. 787.—Exceedingly variable in stature and habit, 2–24 in. high, either stemless with radical leaves and scapes or much branched from the base, with short or long slender sparingly divided leafy stems, glabrescent or tomentose or pilose. Leaves usually numerous, mostly radical, 1–6 in. long, linear-oblong, pinnate or 2-pinnate; leaflets pinnatifid or variously toothed or incised. Peduncles several, usually springing from the rootstocks, but in the branched varieties axillary as well, longer or shorter than the leaves, glabrescent or pilose, especially towards the tip, where the hairs are usually reversed. Umbels few- or many-flowered; involucral bracts 6–8, ovate to linear. Flowers at first sessile, but pedicels lengthening as the fruit ripens, often unequally so. Fruit linear- or ovate-oblong, glabrous or more or less densely pubescent.—Hook. f. Fl. Antarct. ii. 288, t. 101; Benth. Fl. Austral. iii. 377; Kirk, Students' Fl. 197.
Var. Colensoi, Kirk, l.c. 198.—Leaves all radical, pinnate or 2-pinnate; leaflets pinnatifid or incised, ultimate segments acute. Scapes numerous, simple.—O. Colensoi, Hook. f. Fl. Nov. Zel. i. 92; Handb. N.Z. Fl. 91. O. Haastii, Hook. f. l.c.
Var. rigida, Kirk, l.c.—Stems stout, branched at the base only, 4–8 in. high. Leaves 2-pinnate, pubescent or tomentose; leaflets pinnatifid or deeply incised. Scapes stout and rigid, often depressed. Fruits linear.
Var. ramosa, Kirk, l.c.—Stems slender, much branched, often 2 ft. long. Leaves pinnate; leaflets membranous, distant, the lowest petioled, deeply 3–5-lobed or -partite or again pinnate, ultimate segments obtuse or subacute. Peduncles axillary, longer or shorter than the leaves, 3–8-flowered; pedicels unequal, sometimes 2 in. long. Fruits glabrous or pubescent.—O. ramosa, Hook. f. Handb. N.Z. Fl. 91. Mr. Kirk's var. apiculata appears to be a form of this.
North and South Islands, Chatham Islands: Abundant from the East Cape southwards. Sea-level to 4500 ft. November–February. Also in. Australia and Tasmania and in South America.
I have followed Mr. Bentham and the "Index Kewensis" in uniting the three New Zealand species described by Hooker with the American and Australian O. andicola. Any large series of specimens will show that the development or non-development of a branched stem, and the amount of pubescence, which were the characters relied upon for the separation of the species, are in Oreomyrrhis far too variable and inconstant to be employed for that purpose.
