C—B.

The physiognomic plants are Scirpus nodosus, Carex lucida, and Cassinia leptophylla. The two former have the tussock habit, the Scirpus forming large green tussocks 3;' ft. tall, andlthe latter smaller and shock-headed-looking masses about 29 in. by 18 in. in length and breadth and 16 in. tall. The leaves are narrow, arching, and somewhat stiff and coriaceous, yellowish-orange in colour, concave on the upper surface and tapering to a filiform point. Where the boulders crop out to the surface are many low cushions of Muehlenbeckia complexa, and this is the characteristic plant of such ground. Here too is a Coprosma, perhaps a form of C. propinqua, which, owing to the action of the wind, has a most dense habit, which probably is non-hereditary. There is also some Discaria toumatou, likewise so much wind-swept that it is flattened quite to the ground, and hardly recalls the shrub of mountainvalleys. Between the tussocks, on the less obviously stony ground, is a continuous turf of introduced grasses, together with Trifolium repens (white clover), Geranium molle, and a species of moss. Where the soil becomes a little wetter are clumps of the tall broad-leaved sedge Mariscus ustulatus. (d.) Mock Veyttation, <$sc. Cliffs and rocks vary in their plant covering according to their slope and their position with regard to wind and sun. Generally speaking, they have an extremely open vegetation, confined to hollows and crevices. Clumps of Phormium cookianum with broad drooping leaves are very characteristic of the cliffs of the island. Coprosma baueri is frequently flattened close against the rock-faces, its thick glossy leaves rolled up into small compass.* Small bushes of Olearia forsteri, 2 ft. or 3 ft. tall, with rather thick gnarled stems, jut out from the high cliffs. The steepest rock-faces are painted yellow or silver or black with crustaceous lichens. In quite dry places are the ferns Polypodium billardieri and P. serpens, clinging to almost vertical cliffs by their numerous roots. Deep grooves may be filled with Poa anceps. In some places the succulent Peperomia endlicheri is present in considerable quantities. Mesembrianthemum australe may hang in sheets, draping the driest rock-faoes. In dry crevices is Senecio lautus and Colobanihus muelleri. Other fairly common rock-plants are Muehlenbeckia complexa, Linum monogynum, a thick-leaved form of Asplenium flaccidum, Rhagodia nutans, Luzula campestris var., Agropyrum scabrum, Danthonia semiannularis, Scirpus nodosus, Crassula sieberiana, Asplenium obstusatum, Asplenium lucidum, Aspidium richardi, Apium prostratum, Pimelea laevigata var., Tissa media. Stony banks also contain all of the above, and, where moisture exudes from them, Lobelia anceps makes its appearance. At the north end of the island the sea has quite worn down the rock in places into a flat, paving-stone-like surface, between the cracks in which, and in shallow crevices, &c, a peaty soil has accumulated, on which is growing rather a curious assemblage of plants, consisting of a close turf of mosses, grasses, Gnaphalium collinum, Dichondra repens, Oxalis corniculata, Geranium molle, Epilobium nerterioides, Myosotis antarctica, Danthonia semiannularis, Ophioglossum vulgatum, Arthropodium candidum. This association has really nothing whatsoever to do with coastal conditions, but the rock-crevices and peaty soil furnish a substratum of considerable moisture, not altogether unlike that provided artificially for alpine plants in a well-designed rock-garden. (c.) Salt Meadow, Lagoon, and Pond. The only spot noted where salt-meadow plants formed an association was on the shores of the lagoon (marked " Okupe L." on the map) at the north end of the island. This lagoon no longer contains brackish water, and the salt-meadow plants must have occupied this station since the time when there was communication with the sea. The vegetation is best described in connection with that of the lagoon. The lagoon is quite shallow. The bottom consists of soft mud. Its water is fresh. Boulders must exist at no great distance below the mud. Almost the whole surface of the water is covered with a yellowish-green mat of Ruppia maritima. In the shallow places, which must occasionally dry up, is a quantity of Cotula coronopifolia mixed with Scirpus americanus rising here and there out of it, a little Ranunculus acaulis, and Crantzia lineata, the two latter plants extending on to the muddy shore and forming a turf. The shore of the lagoon is a small muddy flat. The plants growing on it are Selliera radicans, forming a turf, as usual, with Triglochin striatum flifolium growing through it, this latter extending to the water and being really the first-comer of the formation ; Ranunculus acaulis, Crantzia lineata, Cotula perpusilla (?), Cotula dioica, Crassula sieberiana. The Selliera has much narrower leaves than is usual. The original lagoon has in large part been changed into swamp. This is not at all, however, of a coastal character; also, it has been much modified by repeated burnings. Its dominant plants are irundo conspicua, Mariscus ustulatus, and Carex ternaria, this latter reappearing after burning. In one part is Typha augustifolia as the dominant plant. Hydrocotyle asiatica is common on the floor of the swamp. Swampy ground exists elsewhere on the island, and that on the Eangitira Plat is richer in species than the above. These comprise Typha angustifolia, Carex secta, Lemna minor, Azolla rubra, Eleocharis cunninghamii, Epilobium chionanthum, E. billardierianum, Ranunculus macropus, Ran. rivularis, Mariscus ustulatus, Hydrocotyle novce-zelandice, Hydrocotyle asiatica, Juncus effusus. Also in other swampy ground was noted Lomaria capensis, Epilobium pallidiflorum, and Scirpus inundatus.

* See Cockayne, L., "On a Specific Case of Leaf-variation in Coprosma baueri, Endl." (Trans. N.Z Inst Vol. xxxviii, p. 341; 1907).

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