Art. XLIV.—A Revision of the New Zealand Species of Colobanthus, Bartling.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 27, 1894, Page 354

Art. XLIV.—A Revision of the New Zealand Species of Colobanthus, Bartling. By T. Kirk, F.L.S. [Read before the Wellington Philosophical Society, 20th February, 1895.] Plates XXVIID. and XXVIIE. All the New Zealand species of Colobanthus are glabrous tufted green or brown herbs, never exceeding 3in. in height except when they form large uneven masses. Their texture

is soft in C. quitensis, C. billardieri, and C. muscoides, but all the others are cartilaginous and rigid; in many cases they present a chaffy appearance. The leaves are small, opposite, and usually linear-subulate in shape, deeply channelled on the upper surface and convex beneath: with few exceptions they are either apiculate or terminate in a long acicular point. The flowers are solitary, and may be almost sessile or carried on longer or shorter peduncles, which rarely are fully 4in. in length, white, and translucent: they are either tetramerous or pentamerous, but the petals are never developed, and the sepals may be either membranous or strongly cartilaginous, while they may equal the ovoid capsule or exceed it by one-third or even one-half: most frequently they resemble the leaves in being apiculate, or tipped with long acicular points. The filaments are flat, alternating with the sepals, and are inserted at the margin of the hypogynous disc, which is sometimes strongly developed, and at others reduced to a mere line. The ovoid capsules are one-celled, containing numerous small almost reniform seeds, which are minutely dotted. To some extent Colobanthus represents the northern genus Sagina, L., in the Southern Hemisphere: the older species were formerly referred to that genus. Colobanthus, Bartling. 1. C. quitensis, Bart. In Reliq. Hænkianæ, ii., 13. Tufted, 1in.-2in. high, soft, green, glabrous, excessively branched. Lower leaves about ½ in. long, with broad membranous bases, concave above, acute; upper frac18;in.–¼in., connate; peduncles-very short, terminal. Sepals 4, ovate-oblong obtuse, the two lateral smaller than the others, one-third longer than the ripe capsule. Disc narrow. Hook. f., Handbook N.Z. Fl., 24: Phil. Cat. Pl. Vasc Chil., 27. Hab. South Island: Nelson Mountains; Kowhai River, Canterbury; Otago. The leaves and sepals of the New Zealand plant are rarely mucronate, but never acicular. This species is found throughout, the Andes, also on Amsterdam Island, & c. 2. C. billardieri, Fenzl. In Ann. des Wien Mus., i., 49. Tufted, forming large patches rarely exceeding an inch in height, flaccid, grassy. Leaves ¼in.—¾in. long, linear-subulate, channelled above, tips acute or acicular; peduncles ¼in.—1in. long, white. Sepals 5, ovate, acute or acuminate, scarcely exceeding the ovary. Disc narrow. Hook. f., Fl. Antarc., i., 26; Fl. Tasm., i., 45; Handbook N.Z. Fl., 25: Raoul, Choix, 48; Benth., Fl. Aust., i., 161; F. Muell., Second Census Aust. Pl., 46. Phil. Cat. Pl. Vasc. Chil., 87. Colo-

banthus affinis, Hook. f., in Hook. Journ. Bot., ii., 410. Spergula affinis, Hook., Ic. Pl., t. 266. Spergula apetala, Labill., Pl. Nov. Holl., i., 112, t. 142; DC., Prodr., i., 395. Hab. South Island: Nelson to Southland. Stewart Island, Auckland and Campbell Islands, Antipodes Island, Macquarie Island. Chiefly at sea-level in the South. Ascends to 3,000ft. in Nelson and Canterbury. Var. alpinus. Much larger than the type, but equally flaccid, and forming small tufts lin.—4in. across, with spreading peduncles 1in.—4in. long. Sepals ovate-acuminate, with membranous margins, slightly exceeding the capsule. Leaves 1in.—2in. long or more, with long acicular tips. Hab. North Island: Ruahine and Tararua Mountains. South Island: Southern Alps. 1,500ft. to 4,500ft. Also in Victoria, Tasmania, Chili, & c. Colobanthus affinis, Hook., figured in Ic. Pl., t. 266, differs from any form of C. billardieri found in New Zealand in the broadly-ovate sepals only half the length of the capsule, and in the wide disc. 3. C. muelleri, n.s. A rigid glabrous plant, forming small tufts ¾in.—1 ½in. high. Leaves usually recurved, broadly channelled, with short acicular tips and evident midrib, ½in.—¾in. long, rarely more, rigid. Peduncles ¼in.—¾in. long, often hidden amongst the leaves. Sepals 5, ovate, abruptly narrowed into channelled points with acicular tips, about one-third longer than the capsule. Disc very narrow. C. billardieri, var. platypoda, F. Mueller, in Veg. Chatham Islands, 11. Stellaria uniflora, Banks and Sol., Mss. in Herb. Mus. Brit. Hab. North and South Islands; chiefly in lowland districts. Mount Camel to Stewart Island; Chatham Islands; but often rare and local. Most plentiful on shingly beaches. I venture to refer the plant collected by Mr. Buchanan at Mount Camel, and by Banks and Solander at Totaranui, to this species, although I have not seen specimens. It is distinguished from the preceding species by its rigid habit, and especially by the cartilaginous apiculate sepals, which are longer than the capsule. Var. multicaulis. Rigid, much-branched from the base, branches naked below. Leaves somewhat lax, spreading, linear-subulate, apiculate, about ¼in. long. Peduncles scarcely exceeding the leaves, slender. Sepals narrow-ovate, acute or mucronate, equalling the capsule.

Hab. South Island: Interior of Otago! J. Buchanan. I have only a few scraps of this interesting form, picked from amongst other plants in Mr. Buchanan's herbarium. 4. C. canaliculatus, n.s. A small tufted much-branched plant, ½in. high, branches spreading. Leaves patent or slightly recurved, 3/16in. long, canaliculate, with stout marginal nerves, sharply apiculate. Flowers ⅛in. long, on very short stout peduncles, axillary or terminating short lateral branchlets; sepals 5, ovate, acute or subacute, equalling the capsule. Disc thickened. Hab. South Island: Central Otago. J. Buchanan! 5. C. repens, Colenso. In Trans. N.Z.Inst., xix. (1886), 260. A small plant forming a matted turf, branches creeping, 3in.—4in. long. Leaves about ½in. long, subulate with acicular tips, not rigid, spreading, green. Scapes slightly exceeding the leaves; sepals 4, broadly ovate, shorter than capsule, slightly margined. Hab. North Island: Near Norsewood, Hawke's Bay. I have not seen specimens of this, which appears to be intermediate between C. muelleri and C. quitensis. I have ventured to abridge Mr. Colenso's original description. 6. C. brevisepalus, n.s. Plate XXVIIE. Tufted, rigid, ½in.—1in. high, much-branched. Leaves densely imbricated, 1/16in.—1/12in. long, linear-subulate, with a broad base, concave above, rounded below, obtuse, mucronate. Flowers terminal, sunk amongst the leaves; sepals 5, narrow-ovate, convex or almost keeled, mucronate, slightly exceeding the capsule. Hab. South Island: Mount Mowatt, Awatere; 4,000ft.; T. Kirk. Gorge Creek and Kurow, Otago; D. Petrie! 7. C. benthamianus, Fenzl. In Ann. des Wien Mus., i., 49. About 1in. high, densely tufted. Leaves rigid, 1/6in.—¼in. long, channelled above, with short acicular points, rounded below. Peduncles very short, flowers distinctly exceeding the terminal leaves. Sepals 5, ovate-subulate, mucronate, rigid, equalling or slightly exceeding the capsule. Disc reduced to a mere line. F. Muell., Second Census Austr. Pl., 46; C. Moore, Handbook Fl. N.S.W., 100; Phil. Cat. Pl. Vasc. Chil., 87. C. subulatus, Hook, f., Fl. Antarc., i., 13, and ii., 247, t. 93; Handbook N.Z. Fl., 25: Benth., Fl. Austr., i., 160. C. pulvinatus, F. Muell., in Trans. Phil. Vict., i., 201, and Pl. Vict., 213, t. 11. Sagina subulata, D'Urville, Fl. Ins. Mal. in Mem. Soc. Linn. Par. iv., 618 (not of Wimm.). Sagina muscosa β, squarrosa, and γ, laricifolia, Banks and Sol., Mss. in Herb. Mus. Brit.

Hab. South Island: “Awatere Valley and Sinclair Range; alt. 4,000ft. Otago: Lake district.” (Handbook N.Z. Fl., p. 25.) Campbell Island. The above description is drawn exclusively from Campbell Island specimens, as all the South Island specimens that have come under my notice appear to belong to the next species, C. acicularis, Hook. f., the leaves and sepals having longer acicular tips than those of the Campbell Island plant, the perianth of which is exactly represented by fig. 4, t. 93, in Fl. Antarc. The drawing of the Falkland Island plant shows a more slender and lax habit than is exhibited by either New Zealand or Campbell Island specimens, while it differs still further in having tetramerous flowers. 8. C. acicularis, Hook. f. Handbook N.Z. Fl., 25. Densely-tufted, rigid, shining green or brown stems, 1in.—3in. long. Leaves densely imbricated, ¼in.—⅜in. long or more, linear-subulate with very long acicular points. Flowers hidden amongst the leaves, almost sessile; sepals 5, linear-lanceolate, with long acicular tips, one-third longer than the capsule. Hab. South Island: In rocky places, Nelson to Southland; 2,500ft. to 5,500ft. A more robust species than the preceding, from which it scarcely differs in essential characters. 9. C. buchanani, n.s. Plate XXVIID. Laxly tufted, glabrous; stems slender, 1in.—3in. high. Leaves loosely crowded, ¼in.—7/16in. long; linear-subulate with acicular points, membranous, concave above, convex beneath, patent or ascending at the tips. Flowers axillary on slender peduncles exceeding the leaves, or rarely shorter; sepals 5, narrow linear-lanceolate, acute, one-half longer than the capsule. Disc narrow. Hab. South Island: Otago; Manuherikia Valley. J. Buchanan! 10. C. muscoides, Hook. f. Fl. Antarc., i., 14. A soft, densely-tufted, bright-green plant, forming amorphous masses 1in.—18in. in diameter or more; excessively branched and matted. Leaves glabrous, densely imbricated, patent or ascending, 1/12in.—¼in. long, linear, obtuse, with dilated bases. Flowers on short peduncles sunk amongst the leaves; sepals 4, ovate-lanceolate, obtuse, concave, equalling the capsule; the two lateral sepals larger than the others. Disc very large. Hook. f., Handbook N.Z. Fl., 25; Decaisne, Voy. au Pôle Sud: Bot. Dicot., t. 17. Hab. The Snares; Auckland and Campbell Islands; Macquarie Island; Antipodes Island.

As the stems become matted they give off rootlets in abundance, while the seeds sometimes germinate in the capsules, and at others are found buried several inches below the surface. I am greatly indebted to Mr. John Buchanan, formerly of the Geological Survey Department, for having so generously placed the contents of his herbarium at my disposal. Explanation of Plates XXVIID. and XXVIIE. Plate XXVIID. Colobanthus buchanani, n.s. Natural size. Fig. 1. Stem, natural size. Fig. 2. Apex of branch, enlarged. Fig. 3. Flower, enlarged. Plate XXVIIE. C. brevisepalus, n.s. Natural size. Fig. 4. Tuft, natural size. Fig. 5. Branch, natural size. Fig. 6. Apex of branch, enlarged. Fig. 7. Leaves and flower, enlarged.