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protected were preserved. In this way areas of Maitai auriferous slates have been preserved between gneissic and other older rocks, and, in like manner,-the Maitai rocks have protected and preserved outlying patches of the coal-bearing series, both at Beefton and in the Grey Valley. This is shown by the manner in which the Maitai series and the coal-rocks are in contact along the east side of the Mount Davy Bange, and by the manner in which the Maitai rocks are in contact with the gneissic rocks of the Paparoa Bange, near the source of Moonlight Creek. And, again, the same thing is exemplified in the Beefton district, and in the gorge of the Buller at and above the Lyell. In these movements the quartz reefs suffered dislocations and displacements that affected them vertically, as well as in a horixontal direction. A study of the movements affecting the coal-rock along the upper part of Murray Creek, and in the range to the eastward, will clearly indicate what the effect of crush and movement has been in the country-rock and auriferous reefs of the neighbouring Maitai series. The gravels of the "Old man bottom" were now deposited and extended in one unbroken sheet from Boss to Beefton; they also filled the greater part, probably the whole, of the Inangahua Valley. They covered the low grounds of the northern part of Westland from the foot of the granite ranges to what is now the sea-coast; and, by way of Big Biver and the sources of Antonio's Creek, they extended farther to the north-east than at the present time they can be traced. Whether at any time the deposit was continuous and connected with the extensive area of the same gravels in the district south of Blind Bay, is perhaps matter for debate. In a previous report* Mr. McKay seems to assume that they are continuous across the upper valley of the Maruia, Matakitaki, &c, and of the Buller itself, into the Motueka Watershed. In this matter he has been misled since the conglomerates in the Upper Maruia, Glenroy, and Matakitaki do not belong to the Pliocene, but to the Cretaceous or Cretaceo-tertiary period, and, as has been noted, are found associated with the coal-bearing beds of that part of the district. We, however, determined the presence of the " Old man bottom " in the district around Merrijigs, at such elevations that the gravels belonging to this formation might very well at one time have extended into the Upper Buller Watershed; and their absence in that part can easily be explained on the assumption that a somewhat greater elevation took place, locally, in this part, which favoured a greater activity of denudation, and, as a consequence, the entire removal of the gravels in question. Upheaval of the land was general, and continued throughout the early part of the Pliocene period, till elevations were reached that induced the accumulation of perennial snowfields, which finally had to be relieved of their excess of snow by glaciers, which, reaching into the low grounds, accumulated morainic matter over surfaces already occupied by gravels of the " Old man bottom." Evidences in proof of this are to be met with at Boss, in Mont dOr, in the upper part of Orwell Creek, in Napoleon Hill, and in the head of the left branch of Noble's Creek, and at the source of Duffer's Creek, and, to a less degree, along the south-east side of the Little Grey Valley as far as Antonio's Flat and Slab-hut Creek. These evidences consist in the presence of angular and very coarse breccia-gravels, containing masses of rock that are quite angular, and of such great size that it would seem that no agency other than that of ice could reasonably be supposed concerned in their transportation from the mountain region to the places where they are now found. In the left branch of Noble's Creek examples came under our notice that were 10ft. to 12ft. across and about the same in thickness. The glaciers, and afterwards the rivers in altered courses, cut down and removed the gravels of the " Old man bottom " from the foot and for three or four miles to the west of the granite range between the Big Grey and Lake Brunner, and at the same time, or subsequently, from the country drained by Snowy Creek. Great changes in the physical outlines of the country began now to be effected, principally through the formation of gigantic faults, which lowered the country along particular lines, disturbing and altering, or completely obliterating, former lines of drainage, and substituting for a general north-east and south-west direction of the drainage a more westerly and direct course to the present sea-board. This was favoured by the disappearance of the western mountains south of the present mouth of the Grey Biver and the Buller, the Grey and Teremakau, the Arahura and the Hokitika —all of them formerly affluents of the great river that collected, carried forward, and deposited the gravel of the "Old man bottom" —now assumed independent courses, courses as direct to the sea as circumstances would admit of. The results were that at many places the gravels of the " Old man bottom " were trenched across, cut down, and carried away, and at others, at a later date, covered up and obscured by glacier deposits that, due to a further elevation of the land, especially along the axis of what are now the Southern Alps, produced glaciers that invaded the lower grounds of the sea-board along the valleys of the Mikonui, Hokitika, Arahura, and Teremakau. These new main drainage-channels favoured —or rather necessitated—the establishment of lesser streams along minor valleys, which, with their several tributaries, cut deep into the gravels of the " Old man bottom;" and in process of time even the least important of these cut deeply into the plateau-like area which they drained, and carried away immense quantities of gravel into the main drainage-channels, which in turn were carried to the sea-board by the rivers, or arranged by them as massive terraces along their lower courses. In time the flat-terrace surface of the area over which the " Old man gravels" extended were sculptured into hills and valleys, while along the lower grounds of the valleys were accumulated gravels, the concentrates of a much vaster amount carried away, which still retained such a percentage of the gold originally in, and washed out of, the older gravels that, on the advent of the gold-miner on the West Coast, these deposits proved to be amongst the richest of the class designated " creek-workings." At the same time it was discovered that the higher beds of the " Old man bottom," which immediately preceded the

* Geological exploration of the northern part of the Westland Goldfields and Mining Reports, 1893, p. 132.

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