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Field-work.—About a month was spent in examining Te Kuiti Subdivision preparatory to writing up the field-work done by the late Dr. H. T. Ferrar by Mr. N. H. Taylor and by Mr. J. H. Williamson. A fortnight was spent in the Moeraki Subdivision with Mr. D. A. Brown examining critical sections and collecting fossils. Professor James Park kindly showed us over the Hampden section and gave us the benefit of his knowledge of the district. A short visit was paid to Takapau, and important fossiliferous outcrops were examined. MICROPALiEONTOLOGY. By H. J. Finlay. Routine examination of numerous samples sent in by field officers has been carried out, and has thrown light oil the stratigraphy of several districts. In Takapau Survey District a number of localities of otherwise uncertain age proved to have a definite Opoiti foraminiferal fauna, though confused, on account of poorly preserved mollusca, with the Mapiri. The ranges of Nonionella stachei and N. Parri were found to give conclusive evidence here. Mr. D. A. Brown sent important collections from the Kakanui and Hampden districts, and the Awamoan and Bortonian of those localities are now well known from good sections. There is now no reason to doubt the Awamoan age of the upper blue clays and brown sandstones at All Day Bay, a series of nine samples at 14-chain intervals showing rich faunas identical with that of Awamoa Creek, and differing so slightly inter se that no practicable zoning could be recognized. Unfortunately, the underlying Hutchinsonian beds yield poorly preserved specimens, and no adequately comparably strict Hutchinsonian fauna has yet been observed. Numerous large faunas examined from Clifden, Pakaurangi, Greymouth, and Takaka are only doubtfully exactly of this age, and this and the facies difference of all Ototaran samples examined makes exact correlation with the Poverty Bay and other distant areas difficult. Complete faunas from all these and many other type localities have been lately examined and mounted for reference. The Moeraki-Hampden beds yielded good faunas over almost the whole of a complete section along the beach taken at 120-chain intervals. The upper micaceous beds have very rich faunas showing at least three definible zones, the middle glauconite bed is almost unfossiliferous, but belongs to the upper series, while the lignitic marls below are devoid of calcareous species, but again show several minor zones based on the arenaceous foraminifera. These horizons can be almost exactly correlated with quite distant ones in Dannevirke and Poverty Bay, the Wanstead of the former and Waitangi bentonitic shale of the latter being facies equivalents of the upper Hampden beds. A large series of samples sent by Mr. A. M. Quennell from the Dannevirke area is in process of examination, and the faunas from Raukaumara (Cretaceous) to Tutamoe (middle Tertiary) show that assignment to the Poverty Bay series of beds, and more or less exact equivalence to the South Island horizons mentioned can be demonstrated. GEOPHYSICAL WORK. By N. Modkiniak. The activities during the past year were concerned in the investigation of part of the Kotuku oilfield, the General Gordon area near Reefton, and the Waiuta area. Concurrently, tests were carried out with the new seismic recorder, ratiometer, and power-buzzer. These instruments were made in the Department's workshop, and required testing under working conditions. Kotuku. Field-work was resumed in the middle of January and continued till the middle of April. The Seismic Refraction method was used throughout the study of the area, which covered approximately two and a half square miles. The area was topographically surveyed by Mr. R. J. Bagge. The preliminary investigation of the area carried out during part of 1937, which was mainly concerned with the testing of an area reasonably well known by previous boring, gave some indications which supported the possible presence of a structural feature, probably a fault, striking in a northwest direction, and offered thereby an explanation of the immediate origin and position of the petroleum and gas seepages. In consequence of this conception the area of interest shifted to the south-west of the above-mentioned fault, and it was therefore selected for the geophysical investigation. The evidence obtained from this study is not convincing enough to justify the assumption of faulting, and the steep slopes indicated by the previous and present surveys are most probably due to erosion of the Blue Bottom formation. Bore No. 14 provides independent evidence for this assumption, as it passed through 482 ft. of Pleistocene gravels and sands without encountering the Blue Bottom formation. All evidence supports Morgan's assumption that Lake Brunner extended northward and that the Pleistocene gravels were deposited in a glacial lake. The slight arching of the Cobden Limestone, known to exist in the northern portion of the area, could also be traced southward, and it was demonstrated that the area is controlled by a single structural unit. Additional information was obtained as to the depth to greywacke basement in this locality, and with this information it could be shown that the pre-Cobden Limestone strata are not sufficiently developed to permit a favourable conception of this locality. This negative interpretation of the results does not apply to the whole area, and merely shows that the chances of success in the localities studied are not favourable enough to start a development programme. Though the expected progressive overlap of pre-Cobden Limestone strata does not occur in a north-south direction, it is probable that such will be the case in a westerly direction towards the Brunner Anticline, where the lower beds missing at Kotuku are fully developed. It is reasonable to assume an accumulation of petroleum, sealed by overlap on the western flank of the Kotuku Anticline,

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