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(■>].) Pimelea arenaria (the Sand Pimelea ; Aute-taranga, Toroheke). Found only in New Zealand; common on dunes everywhere, except in Stewart Island, the Kermadec Islands, and the Subantaretic Islands. Pimelea, arenaria is a close-growing, much-branched, low shrub, its final branchlets erect and forming close masses. The main stems are cord-like, but not as flexible as in Coprosma acerosa, frequently several feet in length, thus having the faculty of lengthening as they are buried. The shrub is leafy at the periphery only for a depth of about 2 in. to 4 in. The prostrate branches finally give off erect, straight twigs, which branch corymbosely at a narrow angle, thus giving a flatfish top to ths shrub. The ultimate and subultimate twigs are alone leafy. The leaves are of a broadly ovate type, about % in. long, closely covered beneath with appressed silky hairs, as are also_ the final twigs. The buds fit in with the station, the hairs of the leaf affording special protection. The flowers arc in close heads at the tips of the branches, and are polygamo-dioecious. The drupe is white and fleshy. The roots are of great length, and adventitious roots are fairly abundant from the uppermost branches, the rest of the shrub being beneath the sand to a variable depth. From the preceding description it may be seen that both P. arenaria and Coprosma acerosa. are' sand-binders to a limited degree, and can with a slow drift continue to grow upwards and rejuvenate themselves, thanks to the power of putting forth adventitious roots from the subultimate twigs. (6.) Cassinia leptophylla (the Cottonwood ; Tauhinu). Found only in New Zealand in the central floristic province. The two closely related plants, C. retorta and C. fulvida, are found, the former in the northern and the latter in the southern province, on the dunes. C. Vauvilliersii occurs in Stewart Island, but it is not a dune plant, though quite well adapted for such a situation. Cassinia leptophylla may be taken as the type of the dune cassinias. It is a shrub of the cricoid habit, from 3 ft. to 5 ft. tall, or even more. The main stems are few, naked, and not much branched at first, but above they branch abundantly into slender leafy twig's, which finally give off at a narrow angle flexible, straight branchlets, which are covered with a moderately loose cottony greyish tonientuni. These final shoots form close masses of leaves, but those of one branch are distinct in themselves, and do not mingle with those of the next. The leaves are very small, narrow, linear or linear-spathulate, ■ r h/in. to -| in. long, patent or semi-imbricating, coriaceous and moderately thick, bright shining green on the upper surface but tomentose beneath, the tonientum being slightly tinged with yellow. The bud-leaves imbricate; they are resiny, and the tomentum of the leaves also affords protection. The flower heads are numerous, white, and in small terminal corymbs 1 in. or more in diameter at the ends of the branches. C. retorta and C. fulvida are very similar to the above; the former has white tomentum, and the latter is almost of a golden colour from the tomentum on the under surface of its leaves and final slender branchlets. It is simply the xerophytic adaptations of the above shrubs which has enabled them to settle upon the dunes, though at the same time the stimulus of the moist sand causes sometimes the putting forth of adventitious roots. (i.) Festuca littoralis (the Sand Fescue'Jjtrass). Found in all parts of the coast of New Zealand, except the Kermadec and Subantaretic Islands; also indigenous in temperate Australia. Festuca littoralis is a "steppe grass," forming close-growing tussocks about 2ft. tall and 5 in. or so through at the base. The underground stems can lengthen upwards to some degree as buried, new roots arising from near the base of the leaves, and plants may rise in this manner 1 ft. or more, thus withstanding a slow burial. The leaves are narrow, strongly involute, green when young or in the shade, but frequently yellowish. The leaf-sheath is pale-coloured and thick. The lamina is 16 in. long or thereabouts, its upper surface furrowed and waxy. The roots are numerous, wiry, brown, furnished with many short filiform rootlets, and frequently spread out laterally for a distance of 3 ft. The panicle is dense, spike-like, and the spikelets turgid. (k.) Calamagrostis (Deyeuxia) Billardieri. Common on New Zealand coast, except in the Kermadec Islands and the Subantaretic Islands; also indigenous in Australia. Calamagrostis Billardieri is a tufted perennial grass forming small green patches about 1 ft. long by 6 in. broad. The tmderground stem is pale, slender, wiry, creeping, and furnished with a great number of slender roots about 6 in. long. The leaves are shorter than the culms, and the blade is bent outwards from the sheath, spreading semi-vertically; it is about 3|- in. long by broad, bright green, flat, membraneous, and tapers to a short point. The panicle is 6 in. to 10 in. long, as broad as long when fully expanded; its branches are hair-like, arranged in whorls, and branch trichotomously. nodosus. Common in New Zealand, except in the Subantaretic Islands, but not confined to the dunes; also indigenous in temperate Australia, Norfolk Island, South Africa, South America, St. Helena, and Amsterdam Island.