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I have much to thank my Nelson friends for, both in the way of information and contribution to my collections, and at the same time indebted to the various gentlemen who, in a spirit of friendship, accompanied me on my journeys.

My best thanks are also due to the various settlers, in whose houses I have found such hospitable quarters. May I be allowed, without mentioning individual names, to express my most sincere thanks to all these gentlemen for their active assistance and valuable contributions to the Novara collection.

I have begun to put together on a map the results of my observations, with the view of laying the foundation of a Geological Map of the Province of Nelson. So soon as time will allow me to complete this map, I will hand over to you a copy of it with pleasure; at the same time expressing a wish that the numerous friends of geology among you, and if they will allow me to say it, my geological scholars here, may continue it and improve it, where I, either from want of time or inaccessibility of the district, have not been able to fill in the details.

I will now come to the subject matter of my lecture.

I.—PHYSICAL FEATURES.

The character of the surface is always more or less indicative of the geological structure of a country. Even to those who have not deeply studied the science, the different forms which mountain ranges show, will indicate a different geological formation. The difference in these external appearances of the country is very striking, if you come from the Northern to the Southern Island.

In contrast with the comparatively low plateaus extending over the largest part of the Northern Island, and broken only by high volcanic peaks, you find on the Middle Island lofty and abrupt mountain ranges, striking in long parallel chains, divided by deep longitudinal valleys, and broken at right angles by rocky gorges. This complication of rock and gorge runs as the great backbone of the island from north-north-east to south-south-west, and from strait to strait. Well do you name it your "Southern Alps." Amongst them rises in grandeur a mountain named after the great discoverer of the South Sea, Mount Cook, of a height equal to Mont Blanc. It towers above the rest, crowned with perpetual snow, with ravines glistening with glacier ice. To the steep perpendicular cliffs with which the Southern Alps breast the stormy sea on the west coast, are opposed fertile plains extending along the eastern shore.

From a central point, which near the boundary line of the two provinces of Canterbury and Nelson) gives rise to the Hurunui and Waiau-ua rivers, flowing to the eastward, and to the Grey and Enungahua, flowing to the westward, the Southern Alps send forth two arms through the province of Nelson, the extremities of which are washed by the waters of Cook Strait. These arms are again subdivided by longitudinal valleys into numerous ranges, with peaks from five to six thousand feet high. I will distinguish between the two arms by giving the name of the "Western Ranges" to those which, with a northerly strike, terminate in Massacre Bay, between Separation Point and Cape Farewell, and the name of the "Eastern Ranges" to those which, running in a north-easterly direction, terminate in the Pelorus and Queen Charlotte Sound.

In the acute angle between the two ranges are situated the Lakes Rotoiti and Rotorua, from which undulating hills, intersected by numerous streams, gradually slope from an altitude of two thousand feet to the plains of the Waimea and the shores of Blind Bay.

I can hardly remember a more beautiful and more striking scene than when I first looked, on a clear winter day, from a high point on the Richmond hills over the fertile Waimea plains, lying like a map beneath my feet, studded with homesteads and covered with cultivations, towards that triangle of snow-capped ranges.

It is, without doubt, in consequence of the peculiar configuration of the mountain ranges, that Blind Bay is favoured with an extraordinarily temperate climate. The western and the eastern ranges of Nelson, converging towards the south, form a regular wedge, which diverts on the one side the force of the south-westerly winds, and on the other side the force of the south-easterly winds. Those parts of the province of Nelson which are not enclosed between the legs of the triangle, do not enjoy the same serenity of climate. In Golden Bay and in the Wairau Country, which lie respectively to the west and to the east in the line of the bounding ranges, gales of wind and bad weather generally are much more frequent than in Blind Bay.

The "spout wind," blowing with considerable violence during the summer from the south, is a local wind of Blind Bay, due to the same physical configuration of the country. The calm heated air of the Waimea plains and of the low hills, rising in obedience to physical laws into the higher levels of the atmosphere, is suddenly replaced by volumes of colder and denser air, which rush down towards the plains from the mountain ranges behind.

I have made these remarks in order to offer an explanation of some of the most striking