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Olearia nummvlarifolia (Photo. No. 19) is a stiff, erect shrub, with rather thick rigid branches, naked below, covered with grey, scaling, furrowed bark, and finally much-branching into short, straight, vertical twiys, which are very closely covered with extremely thick, coriaceous, resinous, tomentose, pale yellow-green, more or less imbricating, recurved leaves. The flower-heads are solitary, and produced in great profusion. The florets are white, but occasionally purple, and the lays are few in number. Cattinia Vauvilliertii, —The volcanic-plateau plant differs considerably from the same species as found in the South Island and the N.Z. subantarctic islands. It is a more or less prostrate shrub, with at first stiff, short, and interlaced branches, and finally short, flexible, straight, leafy twigs, which form a quite close mass. The leaves are small, glutinous, densely tomentose, fulvous to different di sometimes almost golden), more or less imbricating, and very close-set. The flower-heads are very numerous and in rounded corymbs, and the florets arc white. S< in rin BidwiUii is a small shrub with very stout, frequently twisted blanches, covered with a deciduous bark, leafy at their extremities and quite naked beneath. The leaves are of the oblong type, 1 in. or so in length, extremely thick, coriaceous, glabrous, shining-green, and covered beneath thickly with pale-buff tomentum, as are also the final branches anil petioles. The flowers are in terminal corymbs of heads J in. in diameter, with florets oream-coloured and sweet-scented. Carmichaelia Enysii var. orbiculata (Photo. No. "20) is a low-growing shrub, forming dense Hat masses, or sometimes cushions, of green, erect, flat, short, leafless, rigid stems, which are given off from very stout, thick, and woody oreejping branches. The Howers are small and of purplish colour; the root woody, stout, and long. Celmisia spectabilis (Photo. No. 21) is a rather large, herbaceous, or almost suffruticose plant, forming broad roundish mats or lew cushions of leafy rosettes which touch one another and are given off from woody, stout, creeping, and sparsely branching stems, which are covered for the most part with dead and rotten leaf-sheaths. The leaves are of the lanceolate type, thick, flexible, coriaceous, of a shining bright-green colour, furnished with a dense, felt-like, pale-buff-coloured tomentum on the under-surface of the leaf, and having long, fleshy, sheathing petioles, which closely overlap one another and build up a kind of "stem" to the rosettes. The roots are numerous, brown-coloured, cord-like, gradually tapering, and very flexible, and have few lateral thread-like rootlets. The flowers are in solitary heads, on stiff cottony scapes, raised high above the mats of rosettes. The leaf-sheaths remain as decayed masses surrounding the living leafbases and holding much water. Celmisia glandtdota is also a mat-forming plant, with habit similar to the above, but altogether more slender, and smaller in every part. The leaves are in small inseites, about 1 in. long by J in. broad, membraueous, pale-yellowish-green, and covered with minute glandular pubescence. The scape is slender, 2J in. tall, and the head Jin. in diameter or less. Otirisia Colensoi forms mats close to the ground, 2 ft. by 1 ft. in extent, or more. The rhizome is slender, creeping, much-branching, and matted. The leaves are of an oblong type, palishgreen, thick, coriaceous, and arranged in semi-rosettes. The flowering-stem is 3 in. or 4 in. tall, and bears a few white flower-heads i in. or so in diameter. Wahlenbergia saxieola is a small creeping herb having a number of short loaves arranged more or less in rosette fashion, which are green and moderately coriaceous. The peduncles are 3 in. or 4 in. high and one-flowered. The flowers are nearly an inch in diameter, and vary in colour from white to rather dark blue. Qentiana bellidifolia is a low-growing herb having a few dark-coloured leaves of the spathulate type arranged as one or more rosettes close to the ground and terminating the short stem, and furnished with a long, stout, and fleshy deeply descending tap-root. The flowers are large for the size of the plant, while, with numerous slender purple lines (Photo. No. 4). Danthonia Eaovlii is a tussock-grass 2i ft. or more tall. The culms are bunched closely together at the base, which may be 1 ft. in diameter, but the leaves spread outwards as they ascend, arching somewhat near their apices, and here the tussock will be 2 ft. or more through. The leaves ,ne narrow, stiff, thick, cotiaceous, strongly involute, so forming a deep channel, tapering gradually to a long filiform point, pale green, tinged more or less deeply with orange or red. The leaf-sheaths are long, stout, brown-coloured, and persist after the blade has rotted away, forming a close covering round the base of the culm many times larger than the living part. The rhizome is short and woody, and is provided with many long rather wiry roots. Danthonia semiannularis var. setifolia is a small straw-coloured tussock-grass, made up of many close-tufted culms furnished with very narrow, wiry, stiff, filiform leaves, with strongly involute margins, persistent leaf-sheaths, and very numerous slender roots. (c.) The Ecological Factors. With regard to the formations under consideration, the soil factor is of much moment. The very loose nature of the material and its coarse texture render it not merely very porous, but also easily moved, and this is accentuated by the light character- of the scoria and ashes. On slopes its instability debars it from being weathered into more fertile material, and it is only on the flatter ground thai a better soil can by degrees accumulate, aided by the decaying plants, for which it slowly becomes more suitable. Such level ground of the grass- or shrub-steppe frequently contains" a layer-, an inch or two deep at any rate, of a sand black through admixture of plantremains. On the steep slopes, too, the scoria forms a surface layer, beneath which is usually sand, so that distinctly better conditions are offered so far as soil goes than on the shingle-slopes of the non-volcanic mountains. Rain, even if frequent, is not of such importance as the water supplied from below, and which ascends by capillary attraction, since the water-holding capacity of the soil is of the slightest. Also, here the evaporating-power of sun and wind come into play, and the open soil favours