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ward at an angle varying from 2 to 5 deg., and are generally steepest in their upper parts.

Both these terraces form a most prominent feature in the landscape, because, to an altitude of about 5200, feet the mountains are generally smooth and covered with grass and subalpine vegetation, whilst above this we see the rugged and craggy summits of the Alps.

It would be impossible for me to point out all the indications of glacial action found in the valleys, the roches moutonnées on both sides, and the sugar-loafs which exhibit the directions of the marine currents, and I must therefore leave these details to my future report, but I cannot omit noticing one of the most convincing proofs of the glacial period which perhaps is to be found on the globe.

The chain between the main rivers, which form Lake Pukaki and Tekapo, drops near the middle of the latter lake, whilst the former lies about ten miles distant from its terminating spurs, and a large flat, covered by drift formation, lies between and around the lakes.

This drift is cut through by streams flowing into the lakes. When first I reached these lakes I was not a little struck by the manner in which they had been formed, as they are bounded by lateral and terminal moraines of enormous glaciers, which, during the upheaval of the country in the glacial period, had extended to these points. These moraines not only encircle the lakes in a most remarkable manner on three sides, but their constituent debris is often of large size, and as angular and fresh as if freshly fallen from a glacier.

I followed these lateral moraines upwards for many miles, and found them at about 16 miles above the outlet of Lake Pukaki, nearly 1200 feet above the level of the lake, lying on drift deposits, whilst twenty-four miles above the outlet, where the mountains rise steeply from the broad valley, they disappear and are replaced by sloping terraces, the highest of which I observed to be about 2500 feet above the valley, or 4800 above the level of the sea. Their glacial origin is not otherwise observable, the debris of the side moraines having been, in great measure, obliterated by avalanches and mountain torrents or been covered by shingle reaches, but the deep cutting in the mountain sides and the numerous roches moutonnées offer convincing testimonials of their origin.

I shall now proceed to describe some of the physical phenomena which we meet around Lake Pukaki.

Ascending the outlet of this lake from the point at which it unites with that of Lake Tekapo, I found the river flowing over a broad shingly bed, the plains lying only a few feet above the level of the water. The plains here present a smooth surface, rising very gradually towards the lake, about 40 to 50 feet in the mile. Some distance up, the river forms terraces, which, about five miles from the outlet, stand nearly 100 feet above the level of the water.

Beyond this the level appearance of the plains is changed, exhibiting mounds like islands, consisting of large angular erratic blocks.

At first these island-like mounds are not numerous, but become more so as we approach the lakes, and ultimately encircle it like a wall only broken by the outlet. Amongst these elevations we met with numerous lagoons, covered with aquatic birds. These mounds are really ancient moraines, and indicate clearly, even to the unscientific observer who has once seen a glacier with moraine, their true origin. They are about two miles broad.

I may be permitted to offer a few remarks on the causes of the remarkable phenomena by which the formation of these lakes has been brought about, and which afford so convincing a proof of the great duration of the glacial period.

The upper sloping terraces show the different levels at which the glaciers, which then covering the Alps, reached the sea during the gradual upheaval of the land. Their terminal faces, washed by the waves, were broken off and carried away in the form of huge icebergs, as still occurs in the inhospitable polar regions, and even in Terra del Fuego.

By the melting and stranding of these icebergs, the detritus, with which they were charged filled the bottoms of the valleys, the deposits being generally assorted by submarine currents, and the action of the waves in the shallower places. As the country rose, the terminal faces of the glaciers were no longer subjected to marine action, and deposited their detritus load on dry land.

For a long time they seem to have maintained the same degree of magnitude, retreating very slowly, as we see by the different walls, several miles in breadth, which now enclose the lakes. After this, however, they must have retreated more rapidly, until they attained their present position, as in few places only did I see any remains of old moraines.

Not that such moraines do not exist, however, although without doubt the greater part of them are more covered by shingle and boulders, brought down by the rivers which supply the lakes.

These lakes, as is shown by the deltas at their upper end, are, geologically speaking, rapidly filling up. I am also led to believe, from their milky opaque colour, that the lakes themselves are shallow, though I had no opportunity of sounding. The waters of Lakes Pukaki and Tekapo have never been seen clear, which is the more surprising when we observe that the rivers which form them, become, after a continued period of fine weather comparatively clear, presenting the beautiful semi-opaque bluish colour, characteristic of glacial streams.

When surveying this most interesting country, I was often struck by the violence of the wind, which so disturbed the waters of the lakes, as to form quite a surf on their shores, and it is evident, that the dull colour