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forest, and as far as one can see in an upward direction Libocedrus Bidwillii dominates. Dicksun ia lanata still continues in abundance. The other shrubs as from the flat forest are present. Coprosma parviflora and C. cuneata are especially plentiful. There is some Nothofagus Solandri. One has to creep under the projecting shrubs, and their heads intermingle and interlace. Where trees have died (this being a frequent occurrence) and the light enters in, the confusion gets worse, and the density also increases with the steepness." On the dead Libocedrus trees was growing the remarkable filmy fern Hymenophyllum Mallingii, This plant, as Giesenhagen (20) has shown, through its reddish-brown stellate hairs, can keep the leaf-cells surrounded by an envelope of water, a mutter of importance to a bygrophyte, whose special structure renders it especially susceptible to even a very short period of drought. I have myself never seen it growing otherwise than on dead Libocedrus trees,* usually on the standing trunk, where it forme very extensive mats of a silvery or reddish-silvery colour. Even here on Hauhungatahi the portion of the living tree on which I noted the plant was dead and quite decayed. Seen from without, the Hauhungatahi forest is a dark mass marked here and there with the grey colour of dead trees (Photo. No. 30). The yellowish rimus show distinctly as a basal zone. and extend in a straggling manner up the mountain for some distance, but, above, Libocedrus Bidwillii, recognisable at a distance, easily dominates. (C.) DESERTS, STEPPES, AND SCRUBS. (a.) Genekat, Remauks. These formations are so closely related thai they may very well be included under one head. They occupy by far the largest part of the National Park, the forest formations being much smaller in extent. At between 3,000ft. and 3,500ft., plains with an even brown covering of the red tussock Danthonia Raoulii extend for miles, interspersed, it is true, with that open format ion of low-growing shrubs to which I am giving the name of "shrub-steppe," but which is to be found dominant at about 4,000 ft., finally merging into or invaded by deserts of scoria or sand. From an altitude of 5,000 ft. and upwards, with the exception of certain alpine formations on Tongariro, desert, in many places quite without plants, is everywhere. At a distance, the grass-steppe is recognised by its brown colour, the shrubby steppe by the reddiah-orange hue afforded by Dracophyllum recurvum, while the desert appears black or grey according to the colour of the scoria. The steppes are by no means everywhere in their virgin condition. Large anas have been burned from time to time and again and again. This has taken place especially near the ooaoh-road and on the western side of the volcanoes. But the climatic and edaphic conditions are such that the formations are reproduced almost in their primitive form, and the introduced plants which have entered in are not numerous, if we except, in some places, llypochaerh radicata. Certainly at first it looks as if a burnt area were destined to support n new association, a form of Epilobium glabellum being abundant, but this is evidently only a stage in the evolution of the final reproduced formation. (b.) Leading Plants ok Physiognomic Imtohtance. The plants which play the leading part in the physiognomy of the formations are the following :— Shrubs. —(Epacridaceae) Dracophyllum recurvum, Dracophyllum subulatum, Epacris alpina; (Scrophularinaceae) Veronica tetragona, V. Ictvis, V. spathulata, V. Hookeriana; (Rubiaceae) Coprosma depressa, C. cuneata, C. repens; (Taxaceae) Podocarpus nivalis, Phyllocladus alpinus, Dacrydium laxifolium, D. Bidwillii; (Composite) Olearia nummiilarifolia, Cassinia Vauvillierxii. Senecio Bidwillii; (Leguminosae) Garmichaeln Enyrii var. orbiculata. Herbaceous Plants. —(Compositae) Celmisia spectahili*. ('. glandulosa; (Scrophularinaca- ) Oiuisia Colensoi; (Campanulacese) Wahletvhergia saxicola; (Gentianaceir) Qentiana bellidifolia. Grasses. — Danthonia Raoulii, D. semiannularis var. setifolia. Dracophyllum recurvum is a much-spreading prostrate shrub, forming roundish cushions or patches, with much-branching, rigid, and brittle stems covered with dark-grey or brown bark, except the ultimate slender, wiry, and flexible leaf-bearing ones. The leaves are stiff, coriaceous, narrow, recurved, needle-like, tapering to a point, 1 in., more or less, in length, of a glaucous or reddish colour, and crowded into semi-rosettes at the end of the branches. The flowers are in short bracteate terminal spikes, each about Jin. long, and white. The roots are stout, woody, and excessively long. Dracophyllum subulatum is an erect shrub 2 ft. or more tall. The branches are slender, twiggy, and densely arranged, covered with dark bark, and leafy only near their apices. The leaves are small, erect, hardly an inch long, very narrow, coriaceous, stiff, pungent, dull brownish green, with a pale-coloured short sheathing base. The flowers are small, white, and in short racemes. Bpacrit alpina is a small shrub 1 ft., more or less, tall, of an erect and heath-like habit, or frequently with decumbent branches spreading mat-like over a considerable surface of ground. The final branches are vertical and close together, and covered closely with many small, green, thick, hard, coriaceous leaves of an ovate type. The roots descend fairly deep, and are woody, slender, and wiry. The flowers are white, small, and crowded for about half an inch at the ends of the branches. Veronica tetragona, a whipcord veronica, is a small shrub varying much in height, but frequently from 15 in. to 20 in. tall. It forms rounded bushes of semi-erect flexible stems, prostrate *Mr. T. F. Cheeseman informs me lie has observed it on liviny Libocedrus near the summit of Tβ Aroha mountain, but that such a growing-place is quite exceptional.