The textures of the chilled marginal gabbro of the Skaergaard intrusion and of the coarser marginal gabbros 25 yards further in are described and related to counts of the number of separate crystals of the chief mineral species per cubic centimetre of the rock. An explanation of the textures and number of crystal individuals is attempted in terms of various degrees of supersaturation in the magma. In the chilled rock abundant nucleation of plagioclase and olivine, presumably at the middle labile stage of supersaturation, is inferred. This is followed by ophitic or poikilitic crystallization of pyroxene and ilmenite about scarce nuclei, produced at lower temperatures, presumably during the early labile stage of supersaturation for these two minerals. The coarser gabbro, further in from the margin, has about half the number of plagioclase crystals per cm.3 compared with the chilled rock and only one twenty-fifth the number of olivine crystals, and these have a tendency to be ophitic in texture. Under these slower cooling conditions, supersaturation apparently still reached into the middle labile region for plagioclase, giving many nuclei, while olivine, like pyroxene, separated under early labile supersaturation conditions and only relatively few nuclei formed. The contrasting textures of the plateau magma-type basalts of Mull and the tholeiitic basalts of Northern Ireland are explained along similar lines.

Following a recent re-mapping of the district east of Pontesford Hill, Shropshire, it now seems likely that the Uriconian and Longmyndian rocks at The Lyd Hole are faulted against one another, and that the Pontesford Shales form two outcrops, separated by faulting, and not a single outcrop as previously suggested. Doubt is cast on the validity of the so-called “rhyolite” of Habberley Brook, and the faunas and correlation of the Pontesford Shales are reviewed in the light of new evidence.

Five-sixths of all the continental area on the Earth's surface has antipodes in oceanic regions. This proportion is not significantly different from what one would expect on the assumption that the continents are randomly situated.

The Lammermuir-Stranraer moraine was first described by Charlesworth and interpreted by him as marking an important readvance. The central and eastern parts of this feature are discussed. It is concluded that it is not a true moraine in these areas and that the readvance supposed to have formed it did not occur.

Some closed basins extending along the strike of soft rocks in the English and Bristol Channels were cut by sand moved by tidal currents.

Evidence is adduced to relate the published minimum absolute date of — 475 m.y., for the metamorphism of the Connemara Schists, to its correct position in the Lower Palaeozoic stratigraphy of Western Ireland. The metamorphism pre-dates the Didymograptus extensus zone of the Arenig in Connemara and South Mayo and an Upper Cambrian or Tremadocian age is considered likely.

Four Boulder Clay-infilled channels of the upper Afon Rheidol (Cardiganshire) are described as relict river valleys of a progressive localized diversion by glacial interference.

Development of garnet coronas in a small meta-mafite body, forming a tilted dome within the parametamorphics, is reported and the petrography of the coronites is described. Garent coronation marks a stage in the metamorphic and textural evolution of the rocks. The origin of coronas and related features is discussed.

Gabbro is intruded near the contact of gneiss and schist groups in the Southern Province of Northern Rhodesia. The petrography of normal and altered rocks is described. The rocks may have originated as an intrusion into an original reversed drag fold which it has emphasized and distorted. Intrusion took place at a late stage of regional metamorphism and folding.

Recent collecting has revealed a typical cold mollusc fauna in the Cainscross Terrace of the Frome valley near Stroud. Cold conditions are also indicated by lithology and vertebrates. The most likely date seems to be the Irish Sea Glaciation, i.e. the main phase of the Last Glaciation.

Some differential weathering of tors on Bodmin Moor has been found to be due to narrow zones of greisen. These zones are not related to the joint system in the granite and appear to have arisen by the alteration of feldspars in the path of escaping late-magmatic fluids.