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Other supposed coal-indications of a different nature occur in hard blue sandstone and greywacke on the northern banks of the Cherwell River, and in the small branches of that stream draining , Cherwell Flats. They consist of steeply dipping dark pug bands, and are merely comminuted rock along planes of movement. They are of no value as indications of coal. As the district lies on or near the proposed Cheviot-Kaikoura Railway, and the discovery of coal would be a great boon both to the district and the railway, it will be well to give a short outline of the geology of the district, and to indicate the places where coal would be likely to crop out if present. The district has already been noticed at some length by A. lYleKay (Rep. Geol. Explor. during 1885, pp. 80-83), and briefly touched on by J. Park (Trans. N.Z. Inst., xliii, pp. 523-24, 1911). McKay considers that the depression between the Kaikoura Mountains and the coastal ranges to the south of Kaikoura is caused fundamentally by a great fault which has let the Cretaceous rocks down against the older rocks of the Kaiko-ura Mountains. Park, on the other hand, claims that this depression is the floor of an old glacial valley which was overdeepened at Cherwell Flats. Whether either of these views is correct, or both, is immaterial for our present purpose, and need not be discussed here. McKay has given an account, with which I am in general agreement, of the succession of the Cretaceous and " Cretaceo-Tertiary " rocks in Monkeyface and the limestone hills north of the Cherwell River. The Cretaceous beds succeed one another in regular order from the south-east to north-west, and lie unconformably on older (greywacke) rocks to the south-east, where the base of the series is therefore exposed. Three main divisions may be recognized—a basal series of sandstones and conglomerates several hundred feet in thickness, a middle series of sulphur mudstones and greensands (in which McKay has observed a saurian bone), and an upper member having all the characteristics of the Amuri limestone. The latter is clearly exposed in the hills to the north-east of Cherwell Flats. The mudstones and greensands may be seen in the creeks draining the limestone hills, and in a stream running from Monkeyface to the Cherwell River. The conglomerates and sandstones form Monkeyface and the low range running south-west from it and separating the Cherwell Valley from the valleys of the Stag and the Spey. At one place (a sharp peak about half-way between Monkeyface and the first-described coal-indication) the junction with the underlying rocks is only a few feet below the crest of the range on the southeastern side, but north and south of this point it runs into lower ground in the tributaries of the Stag and the Spey, and I had not opportunity to examine it there. Coal may be expected only in the basal series of sandstones and conglomerates if these are of freshwater or estuarine origin at the base. That they are in part marine is shown by two lines of evidence : firstly, the discovery of marine fossils in them near a small lake above the Cherwell River; and, secondly, the abundance of a peculiar grey sandstone with a pcecilitic cement of large calcite crystals which is found also at Amuri Bluff and the Waipara Gorge, in each case in marine strata. On the other hand, the small seam found shows that the lower portion of the series may be non-marine. A knowledge of the Cretaceous shore-lines would be of great service. The district lies nearly half-way between Amuri Bluff and Quail Flat on the middle Clarence River, and the rocks are of the same age in the three localities. At Amuri Bluff the basal beds contain silicified wood in places, but no coal-seams. In the Conway River section of the same rocks to the south-west Haast found no coal in 1870 (Rep. Geol. Explor. during 1870-71, pp. 39-40). On the other hand, at Quail Flat there is a fairly thick seam of inferior coal, and there are also extensive fresh-water beds with plant-fossils. If the Seaward Kaikoura Mountains did not exist at the time of deposition of these beds, then the fresh-water beds must have thinned out gradually from Quail Flat to Amuri Bluff, and must therefore be quite thin or non-existent at Cherwell Flats. If, on the other hand, the Kaikoura Mountains did then exist, the margin of the Amuri Bluff formation must have existed near Cherwell Flats, and the hope of finding freshwater beds and coal-seams is greater. It is therefore a case where a knowledge of the pure geology is not sufficiently advanced to deduce practical conclusions with certainty, and we must await the reconstruction of the old shore-lines based on extensive paleeontological, stratigraphical, and physiographical studies. Meanwhile I should advise prospectors for coal to confine their attention to the neighbourhood of the junction of the sandstone-conglomerate series and the old greywacke rocks in the streams running to the Stag and the Spey. At the same time 1 would not hold out any great hope of success.

6. POSSIBILITY OF OBTAINING GRANITE AND MARBLE SUITABLE FOR BUILDINGSTONES IN THE SANDY BAY DISTRICT, NELSON. By Dr. J. Allan Thomson, Palaeontologist. Sandy Bay lies on the eastern side of hilly country known as the Riwaka Range, which is a southern prolongation of the Pikikiruna Range. The locality at which it is proposed to work granite is in Holyoake's Valley, about three miles from the sea, while the locality for marble is in Marble Creek, a tributary of Holyoake's Creek, entering it on the south side about three miles from its mouth. Access to the district is by a road over the hills from Riwaka, but in the event of quarries being started it is proposed to build a jetty at the mouth of Sandy Bay, from which point a tramway up Holyoake's Valley can easily be constructed.

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