Art. LVII.—Notice of the Occurrence of Triodia and Atropis in New Zealand with Descriptions of new Species.
[Received by the Wellington Philosophical Society, 13th March, 1882.]*
Triodia exigua, n.s.
Danthonia pauciflora, Buchanan, Grasses of N.Z., t. xxxvi. B., not of R. Brown.
A small grass forming a compact swart, root creeping, leaves tufted 1″ long, filiform, rigid, involute, pungent, glabrous, mouth of sheath clothed with a minute pencil of hairs, ligule O. Culms 1″–2″ high, slender, naked above. Panicle reduced to a single spikelet, or rarely two when the lower spikelet is pedicellate. Spikelets 2–3-flowered, empty glumes longer than the flowering, obtuse, flowering glumes 3-toothed at the apex, ciliate, nerved. Palea notched at apex. Caryopsis free.
Hab.—South Island: Broken River Basin, Canterbury, on terraces, 2,500–3000 feet; terraces of the Upper Waimakariri, 1,600–2,500 feet; Mount St. Bathans, Otago—D. Petrie.
Mr. Enys and myself collected a few specimens of this grass several years ago, but as the specimens were far advanced, little more than the outer glume remaining, it was not possible to make out its affinities. Last year Mr. Enys visited the locality and kindly sent me a supply of good specimens. I am also indebted to Mr. Petrie for good specimens from Otago. In his “Indigenous Grasses of New Zealand” Mr. Buchanan has wrongly referred Mr. Petrie's plant to Danthonia pauciflora, but it is clearly a Triodia.
[Footnote] * Title read at Annual Meeting, 12th February, 1881.
Triodia exigua occurs in great abundance in the Broken River Basin, and on the Waimakariri terraces, forming a close sward to the exclusion of all other grasses. Its red anthers, as I learn from Mr. Enys, give a perceptible tinge to the pasturage, which catches the eye when riding. Nearly all the specimens in this locality have the panicle reduced to a single spikelet. Some of Mr. Petrie's specimens are more robust and exhibit two spikelets, the second, however, being often imperfeet. Mr. Enys informs me that horses especially are very fond of it, notwithstanding its dwarf habit.
Danthonia pauciflora of Brown is a more robust grass with keeled leaves and culms with sub-erect or drooping many-flowered panicles which are usually more or less branched, while the flowering glume is never three toothed and the lodicules are never ciliated as in our plant. It has not been observed in New Zealand.
Atropis pumila, n.s.
A slender, tufted grass, 2″–8″ high. Leaves 1″–2″ long, spreading, filiform, involute, with a minute pencil of hairs at the mouth of the sheath. Sheath with a few loose hairs at the base. Culms erect, extremely slender, leafy for over one half their length. Panicle strict, linear-oblong, rarely exceeding 1″ in length, simple or with one or two short branchlets at the base. Spikelets on short capillary pedicels, minute, 2–3 flowered. Outer glumes unequal, obtuse; flowering glume convex, obtuse, 5-nerved; nerves faint; palea ciliolate at the apex; Caryopsis oblong, free.
Hab.—South Island: common in Otago from 2,000 to 3,000 feet- D. Petrie.
I am indebted to Mr. Petrie for specimens of this grass, which adds another genus to our flora. It resembles some forms of Danthonia nuda but its nearest ally amongst New Zealand grasses is Glyceria stricta, Sm.