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probability of the lay of the reefs becoming less broken, though the existence of smaller faults and other irregularities must there also be apprehended oil account of the fissured nature of the country. As regards the continuance of the gold in depth, I see no reason to doubt it, yet I think it very likely that the doubtless increasing abundance of pyrites may, as in Victoria—and this refers also to the reefs of all the other groups —be connected with a corresponding decrease of fine, free gold, in depth. Fifth Gkoitp : The Beefs of Jlfacrac's Flat and Shag Valley. —ln point of definition and mode of occurrence these reefs, which I found all deserted, are, in my opinion, the least promising ones of the province. Judging from those I could examine, and information, obtained about a few others that have been prospected, they represent either so called " layer-lodes " (Duke of Edinburgh Reef, Macrae's Flat, Shag Valley Freehold Company Eeef), or are merely interlaminations between the beds of phyllite that form the country in both districts. • Touching the layer-lodes, their general characteristics are, that they strike and dip with the country, having the foot wall (one and the same country) generally prettv smooth throughout; but the hanging wall mostly quite irregular, uneven and traversed by leaders. They are, on account of this mode of relation to the country, subject to all the changes in strike and dip of the latter, and, if these are great, are liable to frequent changes in thickness, and can generally not be depended on for persistency in depth. In the cases under notice, the stratification of the country is fortunately pretty regular, and all points are therefore in favour of the reefs being also more regular in course and thickness, and having a better chance of persistency in depth than is usually the case. Their dip is rather flat (less than 45°), and they are from 2 to 5 feet thick in the average, being composed of mullock and rather good-looking quartz ; the latter generally predominating and occurring in bunches and veins, mostly on the foot wall, sometimes on the hanging wall, or being irregularly intermixed with the mullock. The gold occurs both in the quartz and the mullock, though mainly in the former, and the yields have ranged from a few dwts. up to 2 oz. per ton, but did not pay in the average; therefore the reefs were abandoned at a very shallow depth. Considering that the gold did not run out, and that the reefs, as far as opened, show a good thickness for considerable extents, in connection with the circumstances under which they were worked, the advisability of giving them another more extensive and systematic trial certainly deserves consideration. With regard to the interlaminations, which were considered to be reefs, and of which some are in places several feet thick, they conform in all respects to what was said about these bodies in the beginning. That they are quite unreliable, concerning gold-bearing character and extent in strike and dip, is proved by the fact that, though several carried good gold (above 1 oz. per ton) near the surface, either their irregularity or impoverishment, or both cases combined, rendered working soon unpayable, and they were deserted in consequence, and, I may remark, do not invite renewed and more extensive prospecting. Sixth Geoitp : Exceptional Occurrences of Gold in Matrix. — The so-called Peninsula Quartz Reef at Portolello.- —These curious occurrences of gold, which I inspected, in company with Captain Hutton, the Provincial Geologist, do not, though believed to do so, represent a quartz reef at all, but are, as far as the superficial workings and the reported results of trials allow one to judge, impregnations of gold in a finely divided state through various kinds of rock that will be described farther on. In a geological point of view the auriferous locality and neighbourhood are the most interesting I have seen during my visit, and would well deserve a special detailed topographical and geological survey. True trachyte, trachyte-breccia, and tufa, and indurated ash-beds, broken through by dykes, and irregular dyke-like masses of basalt, compose principally, as it 6eems, that part of the Peninsula, whilst sedimentary rocks—sandstone and limestone—the geological relation of which requires yet to be determined, form apparently a narrow strip between it and the mountain on which Mr. Larnaeh's mansion is built. This mountain, consisting in its upper part of trachyte and basalt intermixed, seems from half-way down its slope, towards the base, to be composed of sandstone, which in a small quarry is clearly seen to dip underneath the volcanic top rock. As regards the places opened—four in number, in three of which gold has been proved by trial erushings to exist —they lie pretty nearly in a line (the supposed line of reef) down the steep slope of a mountain, at that part composed of greyish-white trachyte. Progressing from above downward, the place highest up the slope consists of an old sawpit, from which a short prospecting drive has been put into the mountain. Quartz of a rather concretionary character was here found in the shape of an irregular bunch, enclosed within trachyte —the whole quantity lying about amounting to about one ton. In this no gold was seen and no trial was made of it, but a specimen has been reserved for assay. The second opening, about 100 feet lower down hill, is a small shallow excavation in trachyte, which is here full of silicious segregations of irregular outline—some nearly one foot in diameter —of a quartzite-like character and bluish-white colour ("bastard quartz," in miners' phrase), in which very fine grains of pyrites can be seen in abundance. Of this stuff, of two trial erushings, one of 2 cwt. gave 18 grains, the second of a ton yielded J oz, of gold; and Messrs. Forbes and McAuley, the prospectors, who kindly showed us over the ground, affirmed that they could wash a pretty fair prospect of fine gold from every tin dishful of the small stuff excavated. In the third opening—a small open cutting, some 60 feet below the previous one—very close-grained white trachyte was excavated, of which a trial crushing of a ton yielded 3 dwts. of gold. The fourth and last opening lies at the foot of the mountain, and consists of a good shaft; of 40 feet in depth, with a small drive at the bottom. It penetrated for the first 25 feet through loose ground, and the last 15 feet through a decomposed cap into a hard coarsely crystalline rock, composed of hornblende, triclinic feldspar, and some quartz, and being more or less densely impregnated with very fine grains of pyrites. This rock continued also in the drive. Three trials were made, viz., two of the hard rock of 1 ton and ■} ton, which yielded respectively 8 dwts. and 11 dwts. of gold ; and the third of 1 ton of the softer decomposed cap-rock, which gave, strangely enough, only 6 dwts. of gold, whilst generally decomposed portions of pyrites-bearing rock are richer than undecomposed ones. All the recorded trial erushings were executed at a good battery in Victoria, and, in order to remove further doubt about the genuineness of this strange auriferous character of the quartzose white trachyte, and the rock from the shaft, several small parcels were most carefully tried in Dunedin, and these all produced gold. Accepting the auriferous character of the rocks, therefore, as satisfactorily proved, and.