ment and is probably tuffaceous. At most places it contains well rounded igneous pebbles, about a quarter of which are volcanic and the tuffaceous material may have been derived from older and not from contemporary volcanics. The volcanics of the Topfer Formation of Reefton are probably of Taitai Series age also, and are represented by non-marine tuffs and agglomerates. Harris (in Suggate, 1957) has suggested that some of the tuffs were formed by pumice eruptions and has described rhyolite, obsidian, and andesite fragments from an agglomerate. Intrusions that are probably of about the same age are more basic in composition. The largest is a dolerite plug near Kirwans Hill; the others are small discontinuous north-west-striking dolerite dykes that penetrate pre-Cretaceous greywacke but do not extend into basal Tertiary coal-measures. Clarence Series volcanics are known only from the Awatere and Clarence Valleys. Thick flows of olivine basalt with interbedded tuffs, partly marine and partly non-marine, originally covered at least 300 square miles. The largest mass preserved covers 10 square miles in the upper Awatere Valley, and is at least 3,000 feet thick, but the other areas of basalt are much smaller and thinner. The volcanics are well exposed but no detailed petrological examination has yet been made. The feeding dykes are also well exposed and penetrate greywacke and the overlying Motuan redeposited beds. The dykes are almost vertical and strike at 104° in Winterton River and at 33° in Hodder River. The basalts and fossiliferous tuffs are underlain and overlain by fossiliferous beds and are well dated as Ngaterian. The eastwards extension of the volcanics is surprisingly limited, the apparently complete Ngaterian section at Coverham, 12 miles east of the probable centre of igneous activity in the upper Awatere, being without any obvious volcanic material. A thin igneous band within the Motuan of Coverham, described as a basalt by Wellman (1955: 100), is possibly a dolerite sill of Ngaterian age. The volcanics of the mid-Clarence Valley have been severely folded and are now confined to three synclinal areas where they cover about four square miles. They probably rapidly thicken westward, the maximum thickness recorded being 1,200 feet (Suggate, 1958). Raukumara Series volcanics are known from two places on the west coast of the South Island. Thick volcanic flows, tuffs, and agglomerates on the east side of the Greymouth coalfield thin to the west within the coal-measures of the lower part of the Paparoa Beds. Underlying rocks are hidden in the centre of volcanic activity and no feeding dykes are known. Basalt interbedded with coal measures of about the same age has been described by Hutton (in Gage and Wellman, 1944) from Koiterangi Hill, 20 miles south of Greymouth. No definite volcanics or tuffaceous sediments are known from the marine beds of the Raukumara Series. Conspicuous red bands in the Mangaotane Mudstone may be tuffaceous, but they do not closely resemble the red tuffs commonly associated with most New Zealand Mesozoic marine basalts. Mata Series igneous rocks are known with certainty only from the Wairarapa. The most recent description is that by Hutton (1943) of those near Ngahape. Intrusions of teschenite and dolerite and variolitic pillow basalts have a fairly high ratio of Na2O to K2O and a low Al2O3 content. The basalts and the chemically similar intrusives are probably Haumurian in age. The teschenites extend well beyond the Ngahape area and intrude Raukumara sediments ten miles south-east at Flat Point and Clarence sediments to the north near Tinui village. In Northland poorly exposed lenses of ultra-basics and allied rocks are surrounded by uppermost Cretactous and lower Tertiary mudstones. Magnetic observations (Jones, 1940) followed by excavations for agricultural serpentine (Andrew, 1942) have shown that the lenses lie along sinuous lines that appear to follow the bedding of the mudstones. Association of basic lavas with the ultrabasics (Bartrum, 1948: 30) suggest that the full igneous suite corresponds with that of the upper Paleozoic