Art. XXXIX.—On some Recent Additions to the New Zealand Flora.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 24, 1891, Page 409

Art. XXXIX.—On some Recent Additions to the New Zealand Flora. By T. F. Cheeseman, F.L.S., Curator of the Auckland Museum. [Read before the Auckland Institute, 2nd November, 1891.] Alectryon excelsum, D C., var. grandis, Cheeseman. A small tree. Habit, size, and general appearance precisely that of the type, and tomentum also the same. Leaves much larger, the whole leaf being often over 18in. long. Leaflets fewer in number, but much larger and broader in proportion, 5in.–7in. long, 2 ½in.–3 ½in. broad, oblong or ovate, acute. Flowers not seen, and only the remains of old seedvessels. Hab. Three Kings Islands: a small clump growing on the cliffs on the northern side of the Great King. A very handsome and striking plant. It differs widely from the type in the size of the leaflets, which are three or four times as large, and also in their shape. It is possible that it is entitled to specific rank, but I hesitate to so place it until flowering specimens have been obtained. Olearia suavis, n. sp. A densely-branched shrub or small tree, 6ft.–18ft. high. Young branches, panicles, and under-surface of leaves covered with pale-yellowish or fulvous tomentum. Leaves usually oblong, but sometimes almost ovoid, occasionally narrower and linear-oblong, obtuse at both ends, ¾in.–2in. long, ½in.–¾in. broad, rather thin, entire or with waved margins; primary veins conspicuous below, almost at right angles to the midrib. Panicles loose, elongate, branches slender. Heads small, ⅙in. diameter; involucre turbinate, scales linear-oblong, pubescent, especially the outer ones. Florets few, small. Ripe achenes not seen. Hab. Mount Arthur plateau, Nelson, alt. 4,000ft.

It is with considerable hesitation that I describe this as new, for in many of its characters it agrees closely with a species published by Mr. Buchanan under the name of O. excorticata (Trans. N.Z. Inst., vol. vi., 241), but of which I have unfortunately been unable to procure authentic specimens. Judging from the description, however, Mr. Buchanan's plant has much larger leaves, said to be acuminate at both ends, and the tomentum appears to be different. Olearia suavis is allied in some respects to O. lacunosa, which is a common plant on the Mount Arthur plateau, but which has much longer and narrower leaves. The tomentum of the two plants is very similar indeed. Myrsine kermadecensis, n. sp. A small glabrous tree, with much of the habit and appearance of Drimys axillaris. Bark rough, blackish - brown. Leaves 2in.-2 ½in. long, obovate-oblong, acute or obtuse, entire, coriaceous, gradually narrowed into short petioles ⅙in.-¼in. long; margins slightly recurved. Flowers small, diœcious (or polygamous?) in many-flowered clusters on the old wood below the leaves. Pedieels short, rarely over ⅕in. Calyx minute, lobes short, broad. Corolla about ⅛in. long, divided nearly to the base into 5 acute lobes, which are fringed at the sides. Anthers nearly as large as the lobes. Drupe globose, ⅓in.-¼in. diameter, black when fully ripe. Hab. Sunday Island, Kermadec Group: abundant over the greater part of the island. This differs from the Norfolk Island variety of M. crassifolia in the smaller leaves, which are much broader in proportion, have longer petioles, and are usually more acute than in M. crassifolia. Mr. W. B. Hemsley, of Kew, informs me that the Australian M. variabilis is a close ally; but I have had no opportunity of comparing the two plants. Bœhmeria dealbata, n. sp. A small tree, 8ft.-25ft. high. Branches terete, hoary with minute hairs. Leaves alternate, ovate, oblong-ovate, or ovatelanceolate, acuminate, obtusely serrate, rounded at the base, 3in.-6in. long, very prominently 3-nerved, and with the secondary veins also strongly marked, green and glabrous and somewhat rugulose above, below white and hoary with minute hairs. Petioles short, stout, grooved on the upper surface. Stipules small, ovate-lanceolate, deciduous. Flowers minute, in small axillary sessile glomerules, monœcious; the female flowers in the glomerules usually expanding before the males. Male flowers: Perianth deeply 4-partite, segments oblongovate, acuminate, covered with erect hairs; stamens 4, alternating with the perianth segments, exserted; a minute

rudiment of an ovary present. Females: Perianth tubular, compressed, dilated below, contracted at the 2-toothed mouth; ovary included, 1-celled, 1-ovulate; stigma exserted, long, filiform, hirsute. Ripe fruit not seen. Hab. Sunday Island, Kermadec Group: not uncommon in the lower portion of the island. This is the plant which I referred to the Norfolk Island B. australis in my catalogue of the plants of the Kermadec Group (Trans. N.Z. Inst., xx., 173). Since then Mr. W. B. Hemsley, of the Royal Gardens, Kew, has done me the favour of comparing it with authentic specimens of B. australis, and informs me that it is certainly distinct, differing in having comparatively shortly petiolate, 3 - nerved, and otherwise strongly-nerved leaves, rugulose above. To this I may add that the leaves are much broader than in B. australis, and not cordate at the base. Mr. Hemsley also remarks that it is intermediate in characters between B. australis and the Lord Howe's Island B. calophylla. A seedling obtained from the Kermadec Islands in 1888 has stood the climate of Auckland well, and is making rapid growth. Its handsome foliage and compact habit should entitle the species to a place in our gardens. Caleana minor, R. Br. (Bentham, “Flora Australiensis,” vi., 366). I am indebted to the Rev. F. H. Spencer for numerous fresh specimens of this singular little plant, collected by him in the vicinity of Rotorua township. The discovery is an interesting one, both on account of its adding a new genus to our flora, and from its affording another proof of the close connection between the OrchideÆ of New Zealand and Australia. Mr. Spencer's specimens exactly match the plate of the species given in Fitzgerald's “Australian Orchids,” and there can be no doubt of the identity of the New Zealand with the Australian plant. Probably it is not uncommon in the Rotorua and Taupo districts, and has been overlooked until now from its small size and inconspicuous character, and from the short duration of its flowering-period. The following description has been drawn up from Mr. Specer's specimens:- Very delicate and glabrous, 6in.-8in. high, usually slightly tinged with red. Leaf solitary, radical, very narrow-linear, rather fleshy, channelled. Flowers 1–3, greenish tinged with red, small, barely ⅓in. long (including the ovary); pedicels ¼in., with minute subtending bracts. Sepals narrow-linear, slightly dilated above the middle, nearly equal in size; the dorsal one attached just above the top of the ovary, the lateral affixed to the basal projection of the column. Petals rather

smaller. Labellum uppermost, very remarkable in shape, the lower portion claw-like, and articulated on to the basal projection of the column; the upper part expanded into a broad lamina, which is peltately attached to the claw. This lamina is convex on its outer or upper side, concave towards the column or on its lower side, rounded at the base, narrowed towards the apex and bluntly 2-lobed. The concave side is smooth, the convex or outer side covered with close-set reddish tubercles, which are longest on the margins. Column horizontal, rather long, with a broad basal projection, broadly winged, concave, forming a horizontally-placed cup or pouch. Hab. Shaded places among Leptospermum, vicinity of Rotorua. Flowers in December and January. The flowers have a most singular and bizarre appearance, and are well worth careful study. Owing to the ovary being recurved, the column is the lowest part of the flower, and forms a shallow cup or pouch. Directly over it is the broad lamina of the labellum, hanging from a delicate claw or ribbon which curves upwards from the basal projection of the column. A very slight pressure on the lamina causes it to overbalance, and it then swings over and descends on to the column, which it closes as with a lid. After a period of rest, it again assumes its previous position. No doubt this remarkable movement is connected with the fertilisation of the plant. It seems probable that small Diptera or other minute insects alight on the labellum, which then capsizes, imprisoning the insects in the concavity of the column; that they then disturb the pollinia, and either fertilise the flower with its own pollen, or when escaping convey the pollinia to other flowers. The latter supposition appears to me the most likely; but Mr. Fitzgerald, who has had good opportunities of studying the fertilisation of the plant in Australia, considers that it is almost invariahly self-fertilised. It is perhaps worth mentioning here that some years ago Mr. W. T. Ball collected a single specimen of a species of Calochilus between Rotorua and Whakarewarewa, and Mr. Spencer has since found it in the same locality. Judging from dried specimens, the plant is either closely allied to or identical with the Australian C. paludosus, Br., which has been collected at Collingwood by Mr. H. H. Travers (Buchanan, Trans. N.Z. Inst., xv., 340).