Manual of the New Zealand Flora.
Order LXXXIX. CentrolepideÆ
Order LXXXIX. CentrolepideÆ.
Annual or perennial tufted often moss-like plants, of small size. Leaves linear or setaceous, either all radical or densely imbricated on the short stems and branches. Flowers very small, usually hermaphrodite, one or several within 1–3 bracts, forming little heads or spikelets terminating short scapes or peduncles. Bracteoles or glumes under each flower 1–3, hyaline, sometimes wanting. Perianth none. Stamens 1–2; filaments filiform; anthers versatile, 1-celled. Ovary either 1-celled, or with 2–3 collateral cells, or of 2 or more free or irregularly connate carpels superposed in 2 rows; ovules solitary and pendulous in each cell or carpel; styles as many as the cells or carpels: stigmas linear. Fruit small, dry, pericarp membranous, the cells or carpels opening extrorsely by a longitudinal slit. Seed pendulous or laterally affixed; albumen farinaceous; embryo minute.
A small and inconspicuous order, comprising 4 or 5 genera and about 30 species. With the exception of the New Zealand species, one found in China, and one in antarctic South America, the order is confined to Australia. It has no properties of importance.
Flowers crowded in a terminal head surrounded by several bracts. Stamens and 1-celled ovaries irregularly mixed, without inner bracts 1. Trithuria. Flowers within 2 alternate bracts, 1–5 within each bract. Stamen 1. Ovary of 3 or more carpels superposed in 2 rows (rarely reduced to 1) 2. Centrolepis. Flowers with 2–3 alternate bracts, 1–2 within each bract. Stamens 2. Ovary of 2 collateral cells or carpels 3. Gaimardia.
1. Trithurxa, Hook. f.
Minute tufted and stemless annual herbs. Leaves all radical, filiform. Scapes short, slender, terminating in several spreading bracts enclosing a head of minute flowers. Flowers numerous, densely crowded, each probably consisting of a single stamen and ovary, but the stamens and ovaries so closely placed as to appear irregularly mixed. Perianth wanting. Stamens with a filiform filament and oblong anther. Carpels 3-angled or compressed in the Australian species, not angled in the one found in New Zealand. Styles 2–3 or numerous. Fruiting carpels 2–3-angled in the Australian species, splitting from the base upwards into as many valves as angles.
The genus also includes 2 species found in Australia.
|1.||T.(?) ineonspicua, Cheesem. n. sp.—A very minute' slender perfectly glabrous annual herb, forming dense moss-like tufts ½–1 in. high. Leaves numerous, all radical, linear-filiform, strict, erect terete, tapering gradually to an acute point. Scapes very short in the flowering stage, lengthening to one-half or three-quarters the length of the leaves when in fruit. Bracts 3–4, erect or erecto-patent, linear-lanceolate, acute, thin and membranous, 1/12–⅛ in. long. Stamens not seen. Ovaries 6–12 or more, densely crowded bright-red, stipitate, ovoid or oblong-ovoid, smooth, not angled nor compressed. Styles numerous, very delicate, forming a spreading brush at the tip of the ovary and much longer than it. Ripe fruit elliptic-ovoid, quite smooth, pale yellow-brown with a dark spot at each end.
North Island: Auckland—Sandy shores of Lake Ngatu, near Ahipara, H. Carse and R. H. Matthews!
A curious little plant, of which I only possess imperfect material. It differs in several respects from Trithuria, and may form the type of a new genus. All the flowers I have examined are without stamens, so that the stamens are either very fugitive, or the flowers are diœcious.
2. Centrolepis, Labill.
Small tufted annual or perennial herbs. Leaves all radical or imbricating along the stems, linear or filiform. Scape slender, terminating in 2 floral bracts which are either subopposite or one a little above the other. Flowers hermaphrodite, sessile, from 1 to 5 within each bract; each flower with 1–3 hyaline scales, or rarely the scales altogether wanting. Stamen 1; filament very long, filiform; anther linear-oblong, 1-celled. Carpels from 3–8 (sometimes reduced to 1), connate and superposed in 2 rows; styles as many as the carpels, filiform, free or connate at the base. Fruiting carpels with a membranous pericarp, longitudinally dehiscent.
A small genus of about. 20 species, all natives of Australia except 3 of those-described herein, and one found in Cambodia.
Slender, annual, not pulvinate. Leaves scapes and bracts hispid. Flowers 3–8 within each bract 1. C. strigosa. Perennial, densely pulvinate. Stems very short, ¼–½ in. Flowers 1 to each bract; carpels 3–5 to each flower 2. C. minima. Perennial, densely pulvinate. Stems soft, ½–1 in., glabrous. Flowers 1 to each bract; carpels 1–3 to each flower 3. C. pallida. Perennial, densely pulvinate. Stems soft, ½–2 in.; sheaths densely hairy. Flowers 1 or rarely 2 to each bract; carpels seldom more than 1 4. C. viridis.
|1.||C. strigosa, Roem and Schult. Syst. i. 43.—A slender tufted annual herb 1–2 in. high. Leaves all radical, much shorter than the scapes, expanded into a broad membranous sheathing base below, above very narrow-linear or filiform, hispid throughout with page 757short spreading hairs. Scapes radical, slender, hispid like the leaves. Floral bracts 2, close together, ovate, awned at the tip, concave, spreading, hispid with long hairs. Flowers from 3 to 8 within each bract, each flower with 3 hyaline scales, the scales unequal in length, the largest one usually as long as the bract, the others shorter. Stamen 1, exserted. Carpels from 3 to 8 in each flower, superposed and connate in 2 rows; styles as many as the carpels, free almost to the base.—Benth. Fl. Austral. vii. 207; Kirk in Trans. N.Z. Inst, xxiii. (1891) 442.
South Island.—Otago—Bluff Hill, Kirk! H. J. Matthews! December–January.
A common Australian and Tasmanian plant.
|2.||C. minima, T. Kirk in Trans. N.Z. Inst, xxiii. (1891) 441.—A minute glabrous densely tufted plant, forming flat moss-like patches. Stems very short, ¼–½ in. high. Leaves equalling or rather shorter than the scape, distichous, linear-subulate, dilated into broad equitant membranous sheaths at the base. Scape short, stout. Floral bracts 2, opposite, ovate, erect, the outer one shortly awned. Flowers 1 to each bract, one of them with a stamen, the other usually without, filament very long. Hyaline scales wanting. Carpels from 2 to 5 to each flower, connate in 2 rows; styles as many as the carpels, connate at the base.
South Island: Westland—Shores of Lake Brunner, kirk! Otago—Lake Te Anau, Petrie! January–March.
Very closely allied to C. pallida, but a smaller stiffer plant, with more-numerous carpels to the flowers.
|3.||C. pallida, Cheesem.—Forming compact pale-green cushion-shaped masses. Stems short, densely packed, ½–1½ in. high, leafy throughout. Leaves closely imbricate, distichous, ⅙–⅓ in. long; sheath half the length of the leaf or more, white and transparent, membranous, glabrous; lamina laterally compressed, ensiform-lanceolate or subulate, acute. Scape terminal, usually shorter than the leaves. Floral bracts 2, close together, unequal, the lower one the largest. Flowers 2, the upper one always with a stamen, the lower one frequently without, filament very long, the anther far exserted. Ovary of 1–3 (rarely 4) superimposed and connate carpels; styles as many as the carpels, connate at the base.—Gaimardia pallida, Hook. f. Fl. Antarct. i. 86. Alepvrum pallidum, Hook. f. Fl. Nov. Zel. i. 268, t. 62c; Handb. N.Z. Fl. 296.
North Island: Euahine Mountains, Colenso, South Island: Otago—Maungatua, Mount Kyeburn, Clinton Valley, Blue Mountains, Petrie! Campbell Island, Sir J. D. Hooker, Kirk! December–March.
Originally described as a Gaimardia, then transferred to Alepyrum, and replaced in Gaimardia by Bentham in the "Genera Plantarum." But the structure of the flowers is not that of a true Gaimardia, and its nearest allies, are undoubtedly C. minima and C. viridis.page 758
|4.||C. viridis, T. Kirk in Trans. N.Z. Inst, xxiii. (1891) 441.—Forming soft green cushions in subalpine bogs sometimes several feet in diam. and 1–2 in. thick or more. Stems very densely compacted, erect, branched, leafy throughout. Leaves numerous, erect, imbricating, with broad scarious sheathing bases, ¼–½ in. long, linear-subulate, channelled in front or terete, tip obtuse or acute, sheaths and sometimes the lower part of the lamina more or less clothed with soft white hairs. Scape terminal, usually exceeding the leaves. Floral bracts 2, alternate but close together, jointed at the base, the lower one with an obtuse often hooked point. Flowers 1 or more rarely 2 to each bract, each flower with a hyaline scale almost as long as the bract. Stamen 1, sometimes deficient in one of the flowers; filament very long. Carpel usually solitary but sometimes 2 connate in the lower flower; style 1 to each carpel, long, filiform.—C. monogyna, Kirk in Journ. Linn. Soc. xix. 286 (not of Benth.). Gairnardia ciliata, Hook. f. Fl. Antarct. i. 85; Handb. N.Z. Fl. 295.
North Island: Base of Ruapehu, Petrie! South Island, Stewart Island, Auckland Islands: Common in subalpine bogs throughout. Usually from 2000 to 5000 ft., but descends to sea-level in Stewart Island. December–March.
This appears to be a much larger plant than the Tasmanian C. monogyna, to which, however, it is certainly very closely allied. Neither it nor the two preceding species fit at all well into Centrolepis, from which they differ in the perennial densely pulvinate habit, the shape of the leaves, the flowers seldom more than one in each floral bract, and in the cells of the ovary (or carpels) being frequently reduced to one. Hieronymus, in his classification of the order given in Engler's Pflanzenfamilien, keeps up the genus Alepyrum for their reception, and probably that is the correct view to take.
3. Gaimardia, Gaud.
Small densely tufted perennial herbs; stems much branched, leafy throughout. Leaves numerous, densely imbricated, linear or setaceous. Scape terminal. Floral bracts 2 or 3, when 3 the upper-one usually empty. Flowers 1 to each bract, sessile or stipitate. Stamens 2; filaments filiform; anthers linear-oblong. Ovary 2- or rarely 3-celled; the cells (or carpels) collateral, connate; styles the same number as the carpels, long, filiform. Fruiting carpels 2, or 1 by abortion.
A small genus of 2 or 3 species, found in antarctic South America, New Zealand, and Tasmania.
|1.||G. setacea, Hook. f. Fl. Nov. Zel. i. 267.—Perennial, densely tufted and compacted, forming broad moss-like patches sometimes 1–3 ft. across. Stems very numerous, branched, erect, leafy throughout, 1–3 in. high. Leaves numerous, erect, densely imbricate, ¼–¾ in. long, linear-setaceous with acicular tips; sheaths broad, membranous, quite glabrous, entire, produced at the tip page 759into a free ligule. Scape terminal, rigid, erect, longer than the-leaves. Floral bracts 2 or 3, alternate, convolute, appressed, obtuse, each 1-flowered or the uppermost empty. Hyaline scales absent. Stamens 2. Ovary of 2 connate collateral carpels; style 1 to each carpel, filiform. Fruiting carpels 2, or 1 bv abortion.—Handb. N.Z. Fl. 297.
South Island, Stewart Island: Not uncommon in subalpine bogs throughout. 2500–4500 ft. December–March.