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they are absent. This, under the circumstances, would barely be possible, and there are no indications in the beds that remain favouring such an assumption. To the contrary, the beds on the mountains of the north-west side of the valley dip to the north-west or west, while opposite, in the low grounds of the valley, the dip is in the same direction. If, therefore, we might be justified in assuming the existence of the line of fault above .indicated, and regarding it as being the chief primary cause of the features that have appeared subsequently, owing to the succeeding erosion of the area, there are yet further and conclusive evidences that disturbances and displacements of the kind indicated did take place, as may be gathered by an examination of the line of involved deposits extending from near the entrance to Parapara Inlet across Washbourne's and the intervening hills to the Parapara River; thence along Glengyle Gully and along the upper part of Appo's Creek to the saddle leading again into the Parapara Valley, the line of dislocation continues along the left bank of the Parapara River to the upper part of Macgregor's Creek, which it follows to Golden Gully and the sources of Wakefield Creek, draining into the Slate River. Further along the line in a south-west direction the evidences of dislocation and displacement of the strata is not so clear, till reaching the south-west end of the Quartz Ranges, where, between Maori Creek and the furthest to which the heavy drifts of the Quartz Ranges can be traced, the auriferous gravels are involved to an unknown depth, and along their south-east boundary cemented and indurated into a hard rock. This line, giving at the surface distinct evidences of its existence, runs sub-parallel with that along the low grounds of the north-west side of the Aorere Valley, in which the evidences of actual fracture are not so clear, but are sufficiently convincing. The line from Parapara to the Quartz Eanges limits to the south-east the younger rocks within the Aorere Valley; also, it limits to the south-east the sloping table-land which has already been described. Along the south-east side of the watershed the mountains rise as rugged heights, which, from their irregularity, indicate varying degrees of resistance to atmospheric or sub-serial denudation. Gravels of different ages, underlain by Tertiary clays, form the rocks of the lower part of the Aorere Valley. From beneath the Tertiary clays, shelly limestone appears on the north-west shore of Parapara Inlet, and in the beds and on the banks of the Aorere, from the junction of Appo's and Stanton's Creeks to the source of Brown's River. Limestones of the same series also dot the surface of the sloping plain at all heights, from the Limestone Knobs on Appo's Creek to " The Castles " on the Rocky River and the limestone rock at the foot of the Pine Ridge, at the southwest end of the Quartz Ranges. The coal-formation is only developed at high levels on the northwest side of the valley, and on that side is followed by conglomerates and quartz-grits underlying limestone of Tertiary age. This, without the coal-measures, is the succession of younger rocks seen on the south-east side of the valley, while in addition, as respects the south-east side of the valley, it has been proved that the conglomerates and quartz-grits are auriferous, and at places rich in gold. The other rocks of the part of the Aorere Valley with which this report is concerned consist of Silurian strata, more or less altered, or completely metamorphosed, and the granite masses of Lead Hill and Mount Olympus. Between the Lower Parapara and the shore of Golden Bay there are limestone and steatite and gneissic rocks, all of which must be regarded as forming part of the Silurian series. The Parapara haematite or iron deposits, though occurring in great mass and forming hills of considerable height, can hardly be regarded as a distinct formation, but must be classed among the Recent rocks of the district. Table op Formations. I. Recent. Low-level alluvial deposits : Aorere Valley, Parapara Inlet, and coast-line. 11. Pleistocene. Gravel terraces not being added to, and but little denuded. Largely developed in Lower Aorere Valley. 111. Pliocene. (a.) Old high-level gravels : Coast-hills, Collingwood to Parapara, south-east side of Aorere Valley, between Appo's Flat and Quartz Ranges. (b.) Older Pliocene gravels : Hills between Lower Kaituna Valley and Rockville. IV. Miocene. Marine marly clays : Aorere Valley and shores of Golden Bay, south-east of Collingwood. V. Eocene. Limestones, shelly or compact, calcareous greensands: Middle part of Aorere Valley. VI. Cretaceo-tertiary. (a.) Conglomerates and quartz-drifts, brown coal: Both sides of Aorere Valley. (b.) Conglomerates and shales, with bituminous coal: North-west side of Aorere Valley. VII. Devonian. Indurated sandstones, red and green breccias : Source of the Slate River. VIII. Silurian. Felspathic slates and sandstones; graphitic, talcose, chloritic, and micaceous schists, gneiss, &c.: Aorere watershed, south-west of Appo's Flat, Parapara River. IX. Granite. Both sides of Aorere Valley. X. Parapara haematite deposit.