Position of Strata and Textue of Rocks.

Near the banks of the Taramakau, the rocks consist of fine light coloured silky clay-slates, nodular schists (Fruchtschiefer), and many other varieties belong to this group, alternating with quartzose schists, which dip to the south-east at an angle of 50 to 55 degrees. Near the sources of the river Styx, a tributary of the Hokitika, the same slate formation occurs in great abundance, but is sometimes more micaceous. There it also dips to the south-east, but at an angle of 70 degrees. Crossing into the head-waters of the Arahura, by the Wooded saddle, where the Waihao formation becomes more developed, the strata in Mount Sale are largely interlaminated with quartz, and page 262dip now to the west-north-west at an angle of 65 degrees, so that here the occurrence of an anticlinal is proved. Still more to the east, at Browning's Pass, the dip alters again to south-east, 70 to 80 degrees; but near the summit of the central axis, westerly dips were again observed. Rocks of the same character, and in similar stratigraphical positions, occur at the head of the more southern branches of the Rakaia, and near the glacier sources of the Rangitata; hut in those localities, the uppermost portion only of the formation under consideration appears, the interlaminations of quartz in the clay-slates (Phyllites), being either absent or appearing in a few instances only. Strata, rich in quartz, are either represented by felstones, or by a semi-crystalline sandstone, in which no particles of slates are enclosed.

On the western side of the Godley glacier altered sedimentary rocks, occur, and the western tributaries of the Great Tasman glacier bring down blocks of rock from the very summits of the Southern Alps, possessing a similar texture. In the Sealy range, south of Mount Cook, and on the western banks of the Tasman river, we meet with foliated altered quartzose schists, argillaceous schists with numerous quartz veins, green calcareous phyllites, true clay-slates or phyllites, some of them passing into gneissoid schists, generally having a westerly dip of 70 to 75 degrees. In the upper course of the two main branches of the Hopkins river, which falls into Lake Ohau, they form the bulk of the ranges where I have traced all the rocks hitherto described. Some of the phyllites are full of lenticular concretions of quartz; in others, the quartz is more regularly interlaminated in small layers, of a few lines in thickness. They vary much in strike and dip, but when all the readings are put together, they prove that at least two anticlinals and synclinals exist, disappearing at last at Mount Hooker, where they are overlaid by newer rocks. Another portion of the country where this formation can be well studied, is situated in the basin of the Makaroa river. Here, on the northern or left bank ot the Wilkin river, it appears to overlie conformably the gneiss granite zone, occuring round Lake Wanaka. The beds representing the Waihao formation, here consist of micaceous or fine grained, light coloured phyllites, often full of laminae of quartz. They are often much contorted, and generally have a dip of between 60 and 80 degrees, varying from north-east to south-west. In crossing Haast Pass, and following the course of the River Haast, we travel upon them for a considerable distance, and are able to observe how the easterly dip changes to a westerly one; and that, after another page 263synclinal has been formed, the easterly dip is again restored on the western slopes of the central chain, where we find them underlaid by the gneiss granite formation. I have spoken of the relation of the rocks in Jackson's Bay, coloured in my map as belonging to this division, when treating of the Westland formation. The rocks in the eastern zone, belonging to the Waihao formation, exhibit a somewhat different facies. There are some micaceous phyllites amongst them but the principal portion consists of peculiarly altered brecciated arenaceous or micaceous schists, alternating with chertoae beds, felstones and greenish schists. Interlaminations of quartz are seldom met with, but very often, parallel to the bedding of the rocks, a congregation of small veins of quartz, somewhat chalcedonic in its nature occurs at intervals, generally anastomosing and continuing its course over a long distance. In the upper course of the Waihao, there is a well defined anticlinal, the rocks dipping on the eastern side 45 to 55 degrees to the east, and on the western side, 70 to 78 degrees to the west. On the eastern banks of the Hakataramea river, all the rocks forming low ranges there, belong to this series. They are sometimes very micaceous, and dip about 60 degrees to the south-west. The outlier on both banks of the Pareora, above Mr. E. Elworthy's station consists of greyish felstones and dark phyllites, dipping 81 degrees to the east-north-east; above them, beds of brecciated micaceous schists are largely developed. The most instructive outlier is the one in the Kakahu river, where some of the schists are so full of interlaminations of quartz, from six lines to three inches in thickness, that the whole appears as one mass of quartz. Other strata contain a close network of small quartz veins. They repose upon beds of highly altered limestone, interstratified with greenish and brownish diabasic ashes and of beds of a quartzoze or chertose character. In some parts of the district, micaceous schists and felstones, intersected by a few well defined quartz reefs, in others, semicrystalline limestones, interbedded with micaceous phyllites, are predominant, apparently forming a number of small synclinals and anticlinals—a south-east and northwest dip, at angles often as high as 85 degrees, being the most frequent. Finally, the small zone in Banks' Peninsula, situated at the head of Lyttelton Harbour, and leading by Gebbie's Pass to Lake Ellesmere, and at the southern base of Castle hill, contains some of the same brecciated micaceous schists, alternating with chertose beds. The strata strike here generally from the north-west to the south-east, with a dip according to the localities, to south-west or north-east, and at a low angle.