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In the present connection it is the Thames-Tokatea rocks to which special reference has to be made. They are here represented as resting on the slates towards the east, and so shown as to appear unconformable to the overlying group, the Kapanga group, while at the same time they rest as the lowest of the volcanic series on the slates to the westward. The evidences leading to these conclusions, it may be, are not to be clearly seen along the line of section; but that they are, is supported by what may be seen a little further south in the sections in the lines passing the Triumph and Tokatea Claims, in which it will be seen that, along this, the position and relations of the Thames-Tokatea rocks cannot well be other than as represented. Another section, taken from Kikowhakarere Bay east across the Tokatea Range to Kennedy Bay and the coast-line a little north of the Bay, shows the increased importance of the ThamesTokatea rocks as they are followed to the southward. In this section is represented the slates of the Maitai series, which as seen at the surface are confined to the eastern side of the range. The probability is that they are present under the crest of the range at and above sea-level, but as yet no workings have shown their presence, and they accordingly are not represented. To the north, on the slope towards Cabbage Bay, the slates show to a height of fully 800 ft. above the sea, and southward on the range in Tokatea Hill they reach to 1,000 ft.; so that, allowing for an old valley or saddle in the slate ridge, slates should still be above the sea datum in the line of section above indicated. In this the rocks of the Thames-Tokatea group are represented : these in this line form the crest of the range and extend down the western slope a short distance. In the lower and second levels of the Triumph Mine, rocks of the Kapanga group are first met with, at the base of which beds of tufaceous shaly clay with impure lignite are met with, beyond which the so-called sandstones of the Thames-Tokatea group are entered upon. The contact of the two groups is represented as proving the unconformity of the two, and, though this is undoubedly their relation ship, it may be that the anticlinal arrangement of the older group is not so evident. This is to some extent inferred from what may be seen on Tokatea Saddle and Hill. The rocks of the group in this line of section are solid and compact, but otherwise represent well the normal characters of the grey sandstone of the miners. In the next section to the south, which in the west commences on the neck of land between Coromandel Harbour and Kikowhakarere Bay, and is thence continued eastward across Dacre's Hill through the Kapanga Claim and across Scotty's Hill to the Tokatea Range, and on the east side of the range to the south side of Kennedy Bay, the Thames-Tokatea rocks form all the higher part of the range, as rocks visible at the surface ; but the slates are met with in all the mine-workings that at levels below 1,000 ft. reach forward any considerable distance westward from the east side of the range. The inner workings connected with the lower levels, Nos. 7, 6, and 5, of the Tokatea and Royal Oak Mines, are all in slate, though slate does not show at the surface on any part of Tokatea Hill. The character of the rock met with in these different workings has already been indicated as being more or less sandy calcareous shales and mudstones, with which are associated thick deposits of the rock called by Professor Hutton felsite tuff. These beds dip at high angles, and the felsite tuff, dipping west, is apparently followed by the calcareous mudstones and shales as overlying beds, thus reversing the order of sequence seen on the shore of the Firth of Thames near Rocky Point. Reefs of gold-bearing quartz from the overlying volcanic group descend into these rocks, and the great "blow" or "buck-reef" of the Tokatea is found in the slates at the western end of the lower or No. 7 adit. The Thames-Tokatea rocks rest on the slates on the east of the main ridge of the range at all levels, and appear down the west slope of the range for at least half the distance from the saddle to the low grounds of Driving Creek. In this section it is difficult to determine which is the lowest rock belonging to the group; but on the west side of the range, on Harbour View and the Peveril claims, it appears to be a coarse ash, or fine-grained breccia. These ash or breccia beds appear not far from the level to which the slates reach in the heart of the range, and the rocks at higher levels in the No. 3 level of the Royal Oak are thick banded tufaceous sandstones, lying nearly flat, or dipping slightly to the north-east. On the east side of the range, these and the associated rocks gradually acquire a higher dip, and with the other succeeding rocks cover up the slates to a depth of 400 ft. or 500 ft., and at the surface continue to the low grounds of the valley leading to the upper end of Kennedy Bay. The line of section crossing this, before it opens out on the broader flats, rises again into a mountain of considerable height, the peak and eastern slope of which show the presence of a younger and unconformable group of volcanic rocks (the Beeson's Island group), that occupies, with the exception of a small outcrop of slate, the country east to the sea. Generally the rocks at the surface, and for the most part the rocky spoil from the mines, are so far decomposed that the original and crystalline character of the rocks has been defaced or effaced altogether, but on the eastern slope there are several outcrops showing in road-cuttings, whence specimens of crystalline rocks in fairly good condition may be collected. On the road-side, near the house occupied by the manager of the Tokatea Mine, there is a massive outcrop of light-grey rock, full of cavities once occupied by minerals that have now disappeared, and only the ground mass of the rock remains. This appears to have been a dyke. It is not traceable to the north-east of the section line, but in the opposite direction it continues to and crosses the mountain road to the Upper Waikoromiko and seems to continue into the higher part of the Success Range, but owing to dense bush, and the rugged nature of the country, it has not been further traced in that direction. On the west side of the range, as stated, the rocks of the Thames-Tokatea group descend some distance below the outcrop of the "big reef," and gradually, as the range is followed southwards, to lower levels. On the road from Driving Creek to the Tokatea Saddle the boundary between these and the Kapanga rocks is across the upper part of the Britannia Claim. Beyond this to the westward the rocks change in character, the Kapanga rocks being coarse greenish breccias and floes of solid andesite, dark or light-grey in colour, the breccias becoming grey in the vicinity of lines of reef quartz. Higher up the range than the outcrop of the " big reef " slates appear in the Peveril Mine. On these rest the ash or fine-grained breccia beds that are here described as the