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opened out by the Parapara Company, and the works in the mud-flat where the elevator has been erected. 3. Washbourne's haematite property, and the Onehunga Iron Company's lease to the south of Washbourne's property. 4. Golden Gully, with reference specially to the areas held and proposed to be acquired by West, Adams, and Fell. 5. The Blue Creek plateau. 6. Lightband's (in part). 7. The Quartz Eanges, with special reference to the areas held by Ziman & Co.; and, lastly, the general geology of the district. As various interests are involved, I shall deal with each locality and. holding separately; but, before doing so, will say a few words on the geological structure of the district, and the relative age of the different strata to be considered. On leaving Collingwood for Parapara and Appo's Plat, the road leads along a pakihi plain, due to the action of the Aorere when running at a higher level than at present. A lower terrace interposes between this and the lowest flat reaching to the banks of the river. The materials forming these terraces are ordinary river-gravels, necessarily derived from all the harder rocks within the Aorere watershed, and, let it be specially remarked, include a fair sprinkling of granite boulders. To the eastward of the higher terrace on the east side of the Aorere Valley, and extending from Collingwood to Parapara Inlet and the north-east part of Appo's Flat, there is a line of hills overlooking Golden Bay, Parapara Inlet, and Appo's Flat. These towards the north are flat topped and covered with gravel similar in character but considerably coarser than those forming the Aorere terraces as above described. Towards their southern end these hills are no longer flat topped, but form a series of rounded elevations, the sides of which show the presence of marly strata which for the present may be regarded as of Cretaceo-tertiary age (their actual age not being readily or as yet determinable). At the north-east corner of Appo's Flat the gravels capping these hills strike away to the westward, and terminate near the mouth of Appo's (Stanton's) Creek, close to the Aorere Eiver. At the north-east corner of Appo's Flat begins quite another feature, characterising the east side of the Aorere Valley as far as the Clark Eiver. This is an uniform slope of the country to the north-west and the low grounds of the valley, from heights 1,200 ft. to 1,500 ft. above the sea, which slope, as seen from a distance, appears to be remarkably uniform, both as regards its dip towards the low grounds and as regards its extension along this side of the Aorere Valley, and suggests at once the idea of a plane of marine denudation, which, by the elevation of the mountain region to the south, has acquired a steeper siope than it had when it was first formed. This sloping plain explains much, and itself requires explanation in order to rightly apprehend the peculiarities of the distribution of the auriferous drifts of the district. Along its south-east boundary extends the deeply involved auriferous drifts of Glengyle and the upper part of Appo's Creek; the Parapara, from Eichmond Hill to the junction of Macgregor's Creek; and Golden Gully to the upper part of Wakefield Creek. This line from its south-western limits, to Parapara mud-flat, is along a line of fracture, and the wash involved is usually tilted so as to stand at high angles, and often so disturbed as to suggest the idea of its having tumbled into a vast chasm or rent rather than being gradually caught up by the progressive movements along a regular line of fault-fissure. Appo's Creek, and Lightband's Creek, and "Coles's Gully Creek cut deeply into the soft carbon schists, and readily decomposed felspathic schists, that form the fundamental rocks of the sloping plain between the deep rim of auriferous wash and the Aorere Eiver. These lesser streams simulate in a remarkable manner the action of the larger streams further to the south-west, the deep-cut channels of the main watercourse and its tributary branches differing only as regards the scale of the operations that have been carried on; Slate Eiver with its tributaries, Eocky Eiver and Snow's Eiver, finding an exact parallel as regards the features described in Appo's Creek and Lightband's Creek. The fracture, and deeply-involved line of auriferous wash, extended north-east and south-west from Parapara mud-flat to Golden Gully, ends at the southern end of the Golden Gully area, and so far as explored is not repeated to the south-west until reaching the Quartz Eanges. The average height of Golden Gully is between I,looft. and 1,200 ft. above the sea, but in the saddle, between the southern part and the Upper Parapara, the quartz-drifts are 150 ft. to 200 ft. higher, and are involved between the older rocks as vertical strata. Above these elevations, and to the south towards the Slate Eiver, the auriferous gravels on Blue Creek plateau are not involved as they are to the north-east, but, as nearly horizontal beds, occupy a slight depression in the slate rock and have their greatest length in a south-west and north-east direction. The material of the wash on Blue Creek plateau is coarser, and mixed with a good deal of slate derived from the immediate neighbourhood. It is also more solid and compact than in Golden Gully, and the stratification, quite undisturbed, shows, in beds of fine grit and quartz-sand in the higher beds, an approach to the conditions obtaining during the accumulation of the Golden Gully deposit. I have not examined the country between Slate Eiver and the Boulder Eiver, but it presents in the higher grounds a line of uniform heights, that are continued across the Boulder Eiver and Salisbury Creek to the southeast margin of the Quartz Eanges, towards the south-west end of which they cease to be isolated hills, and form marked and nearly level terraces. Beyond the Quartz Eanges these terraces are continued into the bush-clad country towards the Clark Eiver. Blue Creek plateau is 1,550 ft. above sea-level. The Castles, between Eocky Eiver and Little Boulder Eiver, reach to about the same height. The terraces mentioned as being at the south-west end of the Quartz Eanges are 1,530 ft. above the sea, and there is thus a remarkable coincidence in the equal levels of the various points bounding the south-east limits of the higher line of auriferous wash between Blue Creek plateau and the south-west end of the Quartz Eanges. Towards the south-west end of the Quartz Eanges the streams cutting into the sloping plain are again of no great volume, and Doctor's Creek and Maori Gully are the counterparts of Appo's Creek, Lightband's and Coles's Creeks, in the north-east part of the line of slope or tilted plane of marine denudation that has already been indicated. The higher part of this slope in the south-west is fully 1,500 ft. above the sea; but from Blue Creek plateau to the north-east corner of Appo's Flat it gradually declines to 385 ft., and the floor of schistose rock reaches sea-level at the point where the road from