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commence the examination is at the Bast Cape. The great leadingrange of Upper Palseozoic rocks (dark sepia) is seen to stretchthrough both Islands as a narrow range, dislocated at Cook Strait ,and spreading out into two branches in the far south to enclose theextensive schistose area of the interior of Otago . Schistose and othermetamorphic rocks (purple and vermilion) are seen to crop out alongthe western base of the mountains of the South Island , and are foundnowhere else, with the exception of small areas on the south side ofCook Strait , where they appear to have been faulted up. On the•eastern side of the mountains we have evidence of a succession of asynclinal or trough-like arrangement of all the formations up to theclose of the Waipara or Cretaceo -tertiary formation (green) ; while theTertiary formations (Upper, chiefly of fluviatile and lacustrine origin-—yellow; and Lower, chiefly of marine origin—pale pink) occupy thebays and indentations of the higher lands, and, although ascendingto a considerable altitude, have their distribution always in obviousrelation to the existing orographical features.

In the North Island the Tertiary formations occupy a muchgreater extent of surface, and have a more continuous distribution."Those of a marine origin form a semicircle, extending from Mokauon the west to the East Cape on the east, and rise from the sea-levelon the coast to 3,700ft. altitude on the south slope of the KaimanawaMountains (Palseozoic slates), the centre of the dome being formedby the great volcanic mountains of Ruapehu and Tongariro , the latterof which is still active. On the other hand, in the north-west part ofthe North Island the Tertiary rocks are, with a few insignificantexceptions, of fluviatile or lacustrine origin, resting unconformably onformations of greater age than the marine Tertiaries, and smotheredby extensive igneous accumulations, the products of long-continuedvolcanic eruptions. The formation of the west coast of both Islands is worthy of attention, taking the scarp of palseozoic rocks that formsthe main range as the division between east and west. Thiscommences on the east coast, at Shag Point, in Otago , and sweepsnorth-west through Mount Cook , across the narrowest part of Cook Strait , and through the North Island , along its eastern border, to theEast Cape. Lying to the west of the longitudinal division thusdefined are three large areas which require special attention, as theyare occupied by exposures of those deep-seated formations which yieldmetallic ores. The first of these is the Otago area, which is the crownof a flat anticlinal dome, the denudation of which has exposed meta-morphic schists over an area of 8,000 square miles, the rocks withinthis area having been changed from the original sediments into