5. Poa matthewsii, sp. nov.
A slender tufted or spreading grass, in the typical form sparingly leafy, 10 in.−20 in. high. Stems branched at the base, striate and grooved, smooth, clothed at anthesis to the base of the panicle by the sheaths of the cauline leaves. Leaves narrow, flat or involute, glabrous, longer than the
pale grooved sheaths; ligule oblong. Panicle narrow (in the typical form) or effuse, usually inclined, 10 in. long or less, distantly branched; branches 2–4, capillary, glabrous or scabrid, sparingly subdivided, bearing few small shortly pedicelled spikelets chiefly along their upper half. Spikelets small, narrow-ovate, ⅛ in. long and about half as broad, usually 4- to 6-flowered, the flowers sessile and crowded on the rachis. Empty glumes unequal, membranous, subacute, half as long as the flowering-glume next above. Flowering-glumes compressed, green or pale, membranous, 5-nerved acute, glabrous or slightly scabrid on the nerves, not webbed at the base, the midrib scabrid; palea two-thirds the length of the glume.
Hab. Waipahi, Kelso, and Cromwell, in Otago, on alluvial flats.
Besides the typical form, I have two well-marked varieties of this grass.
Var. minor.—Plant shorter and more densely tufted leaves slender, involute, much shorter than the culms; panicles shorter and more effuse; spikelets smaller and fewer flowered. This variety grows at Ngapara, near Oamaru, and is most abundant on alluvial flats in the Manuherikia Plain, in Central Otago. A form closely akin to it occurs at Kakanui Mouth, but its panicle is long and very effuse, and the flowers, though small, are normal in number.
Var. tenuis.—Very slender, spreading, with flat leaves and long narrow green spikelets; flowers more distant, with acute strongly nerved glumes that are sometimes slightly webbed at the base. This variety was abundant in valleybottoms in the Catlin's River district before settlement began. The clearing of the bush and the attacks of stock have since almost exterminated it in this district. A better series of specimens than I now possess might prove that var. tenuis is an independent species. Unfortunately, the rich collection of specimens from various stations that I once possessed has been lost, through being lent to the late Mr. T. Kirk to and him in his preparation of a new Flora of New Zealand.
The present grass is of considerable economic value, and would well repay cultivation. It is now to by found only in spots protected from cattle and sheep by shrubby thickets and bushes of Phormium. Var. minor is, however, still abundant, but its value is much less.
Poa matthewsis is, no doubt, one of the grasses of the main islands that Sir Joseph Hooker included in Poa breviglumis, a species, so far as we know, confined to the southern off islands. It is easy to understand how Hooker, with his scanty materials and his desire to avoid setting up invalid
species, came to mass into one specific congeries several distinct plants. It is certain that no form of Poa breviglumis, Hk. f., collected on the main islands exists in any colonial herbarium.
The species is named in compliment to Mr. H. J. Matthews, of the State Forest Department, who has contributed much useful material to my collection, and has for a number of years done notable service to New Zealand botany by collecting and growing numbers of alpine and other interesting native plants. His cultivated series of Veronicas, Gelmisias, Olearias, Ourisias, &c., are of remarkable interest. His garden at Hawthorn Hill, Mornington, Dunedin, is well worth a visit from any one interested in the rarer and more beautiful native plants.