584 Transactions. 
The total annual rainfall at the western coast-line of the South Island 
increases from north to south on account of the coastwards trend of the 
ranges in that direction. This is indicated in the following summarized 
figures for four coastal stations, from Westport in the north to Okuru in the 
south, which have been copied from the New Zealand Geological Survey 
Bulletin No. 18, 1917: Westport, 78:36 in. over a period of twenty-three 
years; Greymouth, 100-90 in. over twenty-five years ; Hokitika, 116-23 in. 
over thirty-four years ; Okuru, 148-16 in. over ten years 
The heaviest rainfall in Westland is experienced on the western flanks 
of the ranges, and especially in the river-gorges. For example, the average 
annual rainfall at Ойга (see map 2, on page 579) for the period 1911-20 was 
195-55 in., and the number of rainy days 176-5. This station lies at the 
western end of Arthur's Pass, at an altitude of 1,255 ft., and its rainfall 
and other meteorological features are probably fairly typical of those of 
similar localities along the west side of the dividing range. From the point 
of view of the fern flora it is important to note that both westerly and 
easterly winds at Otira are far heavier, and the latter wind more drying, 
than in the lowlands of Westland. 
Although the timber-milling industry has been well established in West- 
and for some considerable time, the area still wholly untouched is com- 
paratively large, while in south Westland the forest is practically altogether 
irgin. This is in striking contrast to the condition of the various isolated 
forests in eastern Canterbury, where the pines have largely been cut out, 
and where the only primitive forest is that contained in scenic or water- 
supply reserve blocks. 
the extreme type of New Zealand rain forest is found most characteristic- 
ally in Westland. Here the southern beech, which farther north is present 
along with the taxads, is absent except in the extreme south. e two 
and the taxads Dacrydium cupressinum (rimu, or red-pine), P rp 
kahikatea (kahikatea, or white- pine), P. spicatus (matai, or black - pine) 
and of the higher mountain-slopes. In the former of these the white an 
black pines are practically the only trees present, and the undergrowth 
is composed largely of such small-leaved shrubs as the various species a 
Coprosma. Another association prevails at altitudes of from 1,500 ft. to 
3,000 ft., and consists of the southern rata, the mountain-totara (P odocarpus 
Halli), and the kawhaka (Libocedrus Bidwillii), the other above-mentioned 
