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the gorge the river tends to run close under the mountains on its northern side. These rise with exceeding abruptness to a height of 4,000 ft.; higher than which the culminating peaks are at places clad with alpine grasses, and forms of scrubby vegetation, but, as a rule, are rocky crags separated by impassable gulches. Along the southern bank of the river, and at one place on the northern bank, are vast accumulations of glacial matter, brought down from the upper part of the valley, or of shingle, fan, and slope deposits from tho neighbouring ranges. These have apparently at one time filled the valley to a depth of from 700 to 800 ft., and, in spite of the carrying capacity of the furious mountain torrent that passes through the gorge, the removal of this detrital matter is little better than begun. At the western end of the gorge there are some narrow flats near the level of the river; but even here the southern side of the gorge is buried beneath gravel cliffs and shingle deposit, several hundreds of feet in thickness. Throughout the middle and lower parts of the gorge, wherever it can find footing, heavy or more scrubby forest growth prevails. The river-channel has a fall of 60ft. to the mile in the lower and middle parts, and the fall is somewhat greater in the upper part. In a confined space this would cause a heavy rush of waters, especially should the stream be at all swollen; but, in addition, the narrow river-bed is choked by huge boulders of sandstone, schist, and olivine rock, between which the waters chafe and roar as they find their way through the gorge. This state of things renders the river uncrossable even when low, and thus it was, the track being confined to the south side, that the northern side of the gorge could not be examined or prospected. Such is the noisy violence of the stream, that towards the foot of the Crowbar Gorge, although the track is nearly 300 ft. above tho water, conversation is not easily carried on. Mount Brown Creek, on which is the head-lift of the Humphrey's Gully Water-race, has exposed in its bed the junction between the lower division of the mica schists and the gneissic schists that underlie. Here the second gorge terminates. Immediately west of the junction of Mount Brown Creek from the Mount Tuhua Eange, a line of lower hills, composed of granitoid gneiss stretches north-east to the southern bank of tho river, below which the Arahura enters and traverses an old lake basin now drained by the cutting down of the morainic hills between the southern slopes of Island Hill and the Eocky Pyramid, apart from the western spur of Mount Tuhua, on the south side of the valley. Between the first and second gorges the east and west extension of the bed of this drained lake is between three and four miles; in the opposite direction the width of tho lake was less at the extremities, but a long arm extended north along the valley of the Arahura-Wainihinihini, and its extreme limits in this may not have been less than in the opposite direction. The ArahuraWainihinihini joins the main river about the middle of the Old Lake Basin. Its course is north-east and south-west, parallel to the general trend of the Mica-schist Eange which confines its valley on the eastern side. On the opposite western side the valley is bounded by the peaks of Conical Hill, and Turiwhate, with the Kawhaka Saddle between. Its middle source is on the saddle between Turiwhate and the Mica-schist Eange, the same as that which holds the source of the Big Wainihinihini falling into the Teremakau Eiver. The western branch drains from the Kawhaka Saddle, and drains its waters partly from Island Hill and partly from Turiwhate. The eastern branch is more important, and has its source in the Mica-schist Eange. From this it escapes along a narrow, deep, and utterly impassable gorge, the lower part of which is bounded by walls of gneissic rock. The united branches constitute a moderately-sized stream, having its course along a welltimbered valley to its junction with the Arahura. A mile below the junction, on the left bank of the Arahura, there is a stockman's hut, which served as headquarters while examinations were being made to a convenient distance from it. This position may be regarded as the middle part of the Old Lake Basin. The elevation above the sea is, at this place, 440 f t; at the foot of the second gorge it is between 550 ft. and 600 ft. At the bark hut, in the upper third of the second gorge, the height is I,looft. From the stockman's hut a general view of the upper gorge can be obtained in clear weather ; but, unfortunately, while hero, tho weather was far from being fine. From the same point an excellent general view of the valley of the Arahura-Wainihinihini and the Micaschist Eange can be obtained, as well as of the granite mountains to the north-west and south-east. The depression between the granite and schist ranges to the north-east of this part of the Arahura, on the southern side of its valley, is continued through to Kanieri Lake, between the western spur of Mount Tuhua, and the isolated hill stands apart from it to the north-west. This, however, is not in the direct line of the depression from Bell Hill to the northern bank of the Arahura, which should be continued along the valley of Mount Brown Creek to the upper end of Kanieri Lake. As looked at from the low grounds, in the direction of Mount Brown Creek, the continuation of the depression is less evident; while at the same time it must be said that if the causes of this remarkable feature are what I have considered them to be, then it is by way of Mount Brown Creek tho depression should be continued to the south-west, and the gap leading from this part of the Arahura Valley to the lower end of Lake Kanieri must be referred to the operation of another cause. From the southern slopes of Island Hill, to the rocky hill isolated from Mount Tuhua on the opposite side of the valley, there stretches across the Arahura Valley a glacier moraine of great size. Its surface is uneven, but how far this has been modified by denudation since its original deposition is uncertain. It now forms heights from 800 ft. to 900 ft. above sea-level. It is crescent-shaped, and from the outlet of the Old Lake extends down the river valley a distance of fully two miles, and through it, by a tortuous, narrow channel, the river has cut its way to a depth of 500 ft., so as to effectually drain the former lake, the waters of which were retained by the morainic barrier. On the down-river side the stream has not yet exposed the base of the deposit, and it is uncertain on what rocks it may here rest. Towards the upper end of the gorge the river has cut through the superficial deposits, and exposed massive strata of gneissic schist, striking across the valley from Island Hill. Near the upper end of the gorge, strata of sand and gravel and beds of black sand, oxidized to a brown colour, are seen along the track. Below the gorge, morainic matter forms high cliffs on the north bank of the river, but a moderate breadth of low river-flats are found on the southern side. At higher levels it is probable that glacier-matter is continued along the