Rock and Cliff, | 79 
curtain. But roots are produced on flat or creviced rocks (Plate VI Fig. 9). 
Where exposed to the maximum of spray the Mesemödryanthemum may be the 
sole plant, but throughout the Northern, Central and Southern provinces, it is 
frequently accompanied by Salscornıa australis, Apium prostratum and Senecio 
lautus. In the N. and C., Coprosma Baueri, as a prostrate shrub hugging the 
rock, is common, while in the N. there are often isolated plants, or extensive 
colonies, of the liliaceous herb, Arthropodium cirrhatum, conspicuous with its 
broad, thick, pale-green leaves some 60 cm in length. The fern Asplenium 
RER an occasional plant of the association in the N. and C., is abundant 
in the S ; 
With less spray, other plants enter in and Mesembryanthemum becomes 
of decreasing importance. Rocks of many shapes, the outcome of much weather- 
ing, standing at various distances from the water, obviously offer much more 
varied conditions than a high wall-like cliff, and so possess a richer flora. The 
following are frequently present: — Polypodium diversifolum, Cyclophorus serpens, 
Arundo conspicua (especially in the N.), Poa anceps (var. condensata), Agropyrum 
multiflorum, A. scabrum, Scirpus cernuus, S. nodosus, Cladium Sinclair (N.), 
Leptocarpus simplex, Phormium tenax, Muehlenbeckia complexa, Rhagodia nutans 
(but not S. of Banks Peninsula), Colodanthus Muelleri, Lepidium oleraceum, 
Crassula moschata (5.), Linum monogynum, Coriarıa ruscifolia, Pimelca prostrala, 
Leptospermum scoparium, Samolus repens var. procumbens, Lobelia anceps (N. C. 
and S. to Banks Peninsula and Okarito), Selliera radırans, Lagenophora pumila, 
Sonchus littoralis, and one or other of the species of Cassinia. 
The following 2 plants are restricted in distribution but it is probable that 
together with many of the above they form definite sub-associations: — Aymen- 
anthera crassifolia (virtually confined to the vicinity of Cook Strait and south- 
wards on the E. to North Otago); Copresma Kirkü, a prostrate shrub with 
long, flexible, straggling branches and small, thick, glossy bright-green leaves 
(chiefly in N. of N. Auckland district, but also recorded from the Egmont- 
Wanganui, Ruahine-Cook and E. Cape districts). 
c. Pohutukawa (Metrosideros tomentosa) chf. 
Specially characteristic of northern New Zealand and magnificent when 
loaded at about Christmas with their crimson blossoms are the long lines of 
that massive tree Metrosideros tementosa, jutting from the faces of coastal clifts, 
its spreading branches extending outwards over the rocky shore, at times almost 
dipping into the water: The frequently almost horizontal position of the tree, 
the great weight of trunk and crown, together with the resistance this latter 
offers to the wind, demand efficient means of fixing to the rock. This is met 
by the tree’s innate power to put forth abundance of aerial roots (Plate XIV 
and Figs. 2 and ı0), which spread over the cliff-face and send ee branches E 
deep into the rock. 
The association is made up of a ectisidetnble unbe of species ’ ‚hd { 
een in rt BER. Pe ‚bal, with increase of wind 
