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peculiarities of the Nelson climate, the Montpellier of New Zealand.

II.—GEOLOGICAL FEATURES.

The western and the eastern ranges of Nelson are totally different in their geological character. The western ranges consist of primitive formation, being built up of old crystalline schists, or metamorphic rocks. The eastern ranges are the oldest sedimentary strata, primary formation, broken through in places by masses of plutonic rocks. The lower undulating hills lying in the angle between the two ranges are nothing but an immense accumulation of debris from the mountain ranges on either side, rolled together by the action of the sea, which in former ages washed the bases of the mountains.

When I say, Gold in the western ranges, Copper in the eastern ranges, Coal in the basins between them, I have indicated the chief mineral characteristics of the region referred to. I will now speak more in detail of the

1.—PRIMITIVE FORMATION OF THE WESTERN RANGES.

Taking a cross section from east to west, through the western ranges, we find the subdivisions of the primitive formation succeeding to one another in their normal geological order.

a. Gneiss and Granite Zone.—The western shores of Blind Bay, from Separation Point to Riwaka, consist of granite, bordered on the eastern side opposite to the Tata Islands by gneiss. This same zone of granite and gneiss may be traced in a southerly direction up the Motueka river to the confluence of the Wakapeka, and is cut through by the Buller river, where it enters the gorge of the Devil's Grip on the western ranges, and extends all along the eastern slope of the mountains as far as the Rotorua lake.

b. Zone of Hornblende-schist and Crystalline Limestone (Urkalk).—Proceeding from the granite and gneiss towards the west, we next met, on the top of the Pikererunga range, between Riwaka and Takaka, a broad zone, on which hornblende-schists, quartz-schists, and crystalline limestone succeed one another in regular and numerous alternating strata, with a vertical dip and a strike nearly due north and south. This formation continues in a westerly direction to the opposite side of the Takaka valley, where it is broken through by erupted masses of diorite-porphyry and serpentine, which show themselves in the Stony creek and Waingaroa. The same zone of crystalline schists exhibits itself in the steep escarpments of the gorge of the Wangapeka.

A characteristic feature of this limestone formation is the existence of numerous funnel-shaped pits, which have been hollowed out by the action of water, which has dissolved the limestone.

The interesting phenomenon of the Waikaromu springs in the Takaka valley, where whole rivers suddenly appear on the surface with the water bubbling, is readily explained by a subterranean passage of the water through the limestone from the ranges. This crystalline limestone on the ranges must not be confounded with the other limestone in the Takaka valley, which belongs to the tertiary period.

c. Mica-schist and Quartz-schist.—The crest of the western ranges, with peaks rising to an altitude of about 6,000 feet, the Anatoki mountains, Mount Arthur, and the chain lying between the source of the Wangapeka river and the Buller river, consists of mica-schists, containing garnets, alternating with quartz-schists.

d. Zone of Clay-slate.—Still proceeding towards the west, the mica-schists, by insensible gradations, into clay-slates, which, however, still exhibit the same alternating strata of quartz-schist. The Aorere valley and the lofty peaks on its eastern side, as the Slate-river peak, Lead Hill, Mount Olympus, and the Haupiri range, generally belong to the clay-slate zone. In all these ranges the strata are more or less vertical, and exhibit unmistakable signs of great disturbance at former geological periods. For instance, Mount Olympus presents the peculiar appearance of strata diverging from below towards the serrated edge of the mountain, like the folds of a fan. A similar disposition of strata is observed on the loftiest summit of Europe, namely, on Mont Blanc.

GOLD.

In the mica-slate and clay-slate zone of the western ranges, we have the matrix of the gold. From the interest attaching to this subject, I may be allowed to repeat the limits of these gold-bearing formations. On the east these formations are bounded by the Takaka valley; on the west by the Aorere valley, so that its breadth is from fifteen to twenty miles, and includes the Anatoki and Haupiri ranges. In a southerly direction the same formations can be traced to the gorge of the Buller river. How much further it extends in that direction has not yet been ascertained; but, inasmuch as gold has been found at the northern extremity of the Southern Alps, and also in the gravels of the Mataura, in the Province of Otago, towards the southern extremity of the backbone, it is not unreasonable to infer that the same gold-bearing zone may extend con-