The Wealden of the Weald is mainly post-Tithonian/pre-Aptian in age. The formation probably comprises the fullest non-marine record of the interval in north-western Europe, spanning most of Berriasian (Infra-Valanginian), Valanginian, Hauterivian and Barremian time. It is well suited to be the standard succession for purposes of direct correlation.

The term “ Wealden ” should, if used for beds outside the English basin, be applied only to those non-marine formations (1) clearly lying within the Berriasian–Barremian range and, if possible, (2) correlatable directly with the standard. Otherwise “ Wealden facies ” should be used.

Beds claimed as “ Wealden ” elsewhere in north-western Europe are examined in this light.

Various aspects of the terms teschenite and crinanite are discussed, including their usage in relation to petrogenesis. It is suggested that the use of the term crinanite be discontinued.

Thermal metamorphism of zeolites in amygdales of basaltic rocks is shown to give glomero-porphyroblastic aggregates of plagioclase crystals. Plagioclase phenocrysts in basic rocks are shown to undergo but little change during similar degrees of metamorphism.

A swarm of basaltic and camptonitic dykes in the Northern Highlands of Scotland has been studied. The dykes include monchiquite, olivine basalt, olivine dolerite, and camptonite, and a study of the relations of the various types in individual dykes suggests that the camptonites have arisen by the crystallization of late fractions from a magma of fairly normal dolerite type.

Sillimanite produced by the contact action of the Donegal Granite shows varied textural and time relationships with the other minerals of the schists in which it occurs. Early Sillimanite was formed in the main stage of metamorphism by destruction of biotite, K, Fe, and Mg being expelled in the process. A later influx of new K from the granite led to the growth of muscovite metacrysts. This was associated with destruction of part of the early Sillimanite, recrystallization of part, growth of a new crop of Sillimanite needles, and formation of muscovite-sillimanite intergrowths.

The structure and flow-layering of a granodiorite dyke, as seen in extensive quarry exposures, are described and related to quarrying directions and the regional tectonic pattern.

The mode of occurrence and petrography of a group of pyroxene- hornblende-granulites (beerbachites), found only in association with serpentinized peridotite, are described. The beerbachites are regarded as contact altered lavas and basic intrusions which formed the lower levels of a thick series of Ordovician volcanics. Peridotite, intruded into the base of the volcanic pile, disrupted and thermally metamosphosed the lavas and intrusions which appear as inclusions in the serpentinized peridotite. The present contacts between serpentinite and adjacent unmetamorphosed rocks are secondary in origin.

New discoveries of marine Lower Miocene beds on the Tanganyika and Kenya coasts and on the adjacent larger islands are briefly described, and the palaeontological evidence establishing their age outlined. Previous palaeontological evidence has had to be reassessed, a considerable number of supposed Pliocene index fossils having been found to occur in the Lower Miocene. The “ Chlamys werthi Beds ” are shown to include strata of both Lower Miocene and Pliocene ages.

The East Asian Cretaceous lamellibranch genera Trigonioides and Hoffetrigonia are discussed after examining new material of the former, and the conclusion is reached that both belong to the Unionidae and not to the Trigoniidae. A proposal to include them in a new family is withdrawn.