Intrusion of an adamellite with K-feldspar megacrysts into metadolerite wall-rock has produced a hybrid rock with K-feldspar porphyroblasts and quartz “ocelli” rimmed by hornblende. This indicates a high-level development of the feldspar and suggests that mafic contamination is an important factor in the genesis of the xenolith-rich porphyritic adamellite.

Tracks believed to have been made by a crawling gasteropod are described from a loose block of Upper Carboniferous grit from Soyland Moor, near Todmorden, Yorkshire.

The properties of bottomset deposits found in the lee of ripples and dunes formed in water depend on: (i) the diffusion and settling of grains driven over the crest of the sand body and (ii) the redistribution of grains over the bed due to the expenditure of fluid power in the recirculating eddy to the lee of the body. Experiment shows that the rate of grain settling in the lee of a sand body falls off hyperbolically downstream. The bottomset deposits of ripples and dunes also attenuate in thickness downstream, but reach a zero thickness commonly at 4–5 ripple- or dune-heights downstream from the crests. Bottomsets may consist partly or wholly of settled grains, but can also be formed when no sediment settles in the lee of a sand body.

Some basaltic and andesitic rocks from the Tweed Shield Volcano are tholeiitic in character as evidenced by their chemistry and the nature of their pyroxenes inferred from optical data. A common mineral assemblage in the more basic members is olivine-clinopyroxene-plagioclase-opaques-(glass). Petrographic criteria that characterize tholeiites are often lacking, and some of the more basic lavas appear to link the more typical tholeiites with transitional olivine basalts. Many of the Tweed volcanic rocks are more potassic than similar rocks in other tholeiitic sequences. The likelihood of differing lineages in the shield area is noted.

The Rokel River Series of Sierra Leone is re-defined, and subdivided into the Rokel River Group and the Taban Formation. The Rokel River Group consists of six formations which represent the development and infilling of an eugeosyncline, and has been mildly metamorphosed and folded at least three times. The Taban Formation contains fluvial sediments deposited after orogenesis.

Remains of coleoptera collected by Miss Chandler from the Barnwell Station beds (Cambridge) are described. Twenty-one recognizable taxa are recorded, all of which represent living genera or species. Five species are no longer found living in Britain and are confined today to arctic or sub-arctic environments. This interpretation of the fauna is in marked contrast to the identifications of P. Lesne, whose manuscript determinations are attached to the slides. He had attributed many of the specimens to new genera and species.

The fauna as here interpreted indicates a truly tundra environment and qualitatively and quantitatively resembles very closely other British coleopteran assemblages from the latter part of the Upton Warren (Mid-Weichselian) interstadial, i.e. about 30,000 years B.P.

Five faunal lists of conodonts recovered from isolated Viséan outcrops in the north of England are presented. The fauna of the Bowland Shale at Burnsall, Yorkshire, and that of the Orionastraea Bed at Bordley, Yorkshire, are representative of the Gnathodus mononodosus Assemblage Zone. The fauna of the Bollandoceras hodderense Bed (B1), and that of a limestone near the top of the Worston Shale Group (B2) at Little Mearley, Lancashire, represent the Mestognathus beckmanni-Gnathodus bilineatus Assemblage Zone. The presence of conodonts in the reef limestone of Swinden, Yorkshire, is also noted.

The discovery of species of Kootenia and Bailiella known from the Middle Cambrian of western Newfoundland (“Pacific Province”) and southeastern Newfoundland (“Atlantic Province”) in limestone within volcanic rocks near New World Island, eastern Notre Dame Bay, is the first demonstration of the presence of Cambrian in the volcanic belts in North America, and also shows the mixing of forms from the two provinces.

The system of stratigraphic classification used by field geologists working in Africa is briefly reviewed and a hierarchy of terms is suggested, taking into account the requirements of those interested in local field problems and those concerned with the tectonics and composition of the African continent as a whole. On the local scale, rock units are best named according to the lithostratigraphic classification. On a regional scale, the criteria for defining rock units are essentially tectonostratigraphic and two new terms for them, in ascending order of magnitude, Orogenic Assemblage and Orogenic Complex, are proposed. The two schemes are united through the Sequence, which can contain any number of lithostratigraphic units of any order of magnitude.

The Pre-Cambrian rocks of the Grenville province of south-west Quebec in the Mont Tremblant Park area consists of granulites and associated gneisses formed under granulite facies conditions which are intruded by members of an anorthosite suite. At the contacts of these intrusives especially the late-stage members, the granulites and gneisses were found to be retrograded into rocks with mineral assemblages typical of the amphibolite facies. The transformation of the granulite facies rocks into rocks of lower amphibolite grade can be attributed to local introduction of water which was supplied during the emplacement and crystallization of this late-stage, volatile-enriched magma of the anorthosite suite.

Banded pumice from a late-Tertiary ignimbrite in northern Chile is descrived and its origin considered. Other phenomena within the ignimbrite, including a variation in mineralogy between the upper and lower units of the flow, are described.

In the Jimberlana Norite the heteradcumulate and adcumulate rocks are found in adjacent layers. The heteradcumulate occur immediately before the heterad minerals appear as cumulus grains in an adcumulate rock. It is considered that both heteradcumulate and adcumulate textures result from supercooling in the magma. Heteradcumulates develop when seeds of the heterad mineral are not available in the magma and adcumulates after they have formed.