The distribution of Ba, Mn, Nb, Rb, Sr and Zr has been studied in the granites of the Rosses complex. Their variation is interpreted in terms of a process of magmatic evolution involving the formation of granite magma by progressive partial fusion, and its modification during emplacement by the partial assimilation of displaced country rocks. Several greisens from the Rosses complex have also been analysed, and the changes in concentration of trace elements during greisenization are related to observed changes in mineralogy.

The Juan Fernandez Archipelago, located off the coast of Chile, comprises a group of three small, considerably eroded volcanic islands, probably of late Tertiary age. Traces of old craters or calderas have been recognized on Robinson Crusoe Island which is built mainly of basaltic lava flows, many of them picrite-basalts. Coarse-grained ejected blocks, in which olivine predominates, are fairly common on Robinson Crusoe and there are also a number of exposures of dolerite showing pronounced banding. The only acid rock reported from the group is a soda-trachyte from Alexander Selkirk Island. Pumice washed ashore on the islands during the past year is possibly from a submarine eruption near the South Sandwich Islands in 1962.

Easter Island comprises three major volcanoes, Poike a simple strato-volcano, Rano Kau which is of similar size but with a caldera at its summit, and Terevaka which is the largest and most complex of the three. In addition there are about seventy minor eruptive centres. The lavas constitute an alkali-basalt-trachyte-soda-rhyolite series but the acid members are of very restricted development. There is evidence that the parasitic tuff cone of Rano Raraku has had a more complicated history than previous reports have suggested. Although no volcanic activity has ever been reported, some of the lava flows appear to be of very recent origin.

A simple visual method for distinguishing important Devonian atrypid brachiopod taxa, and for separating the Atrypidae and Palaferellidae family-groups is outlined. The thickness, distribution, and repetition of the three layers of impunctate atrypid shell wall differ markedly from one genus to the next and show a general evolutionary trend towards reduction and simplification.

Recent studies in N.W. England have indicated the need for a review of Wenlock and Ludlow (Silurian) stratigraphy. Detailed re-mapping, mainly for the first time since 1872, has modified and more clearly defined the established terminology. Determinations of new graptolite and shelly faunas have resulted in a revision of some earlier work and the establishment of a modern zonal classification for parts of the Wenlock and Ludlow. Lithofacies are broadly summarized and described with comments on some palaeocurrent data.

Early diagenetic, micritic, carbonate concretions from Namurian goniatite bands in Staffordshire and Derbyshire contain Radiolaria and sponges excellently preserved owing to replacement by ankeritic dolomite anhedra. The microfossils are detectable only by acid etching of limestone surfaces and thin sections. Preservation by the dolomite is believed to occur under restricted conditions in which silica solution and dolomite crystallization post-date a phase of rapid calcite crystallization.

A new specimen of the rare spiriferide brachiopod Bittnerula zitteli (Bittner), from the St. Cassian beds (Triassic) of the Italian Alps, has a well-preserved ventral umbo with a small sub-apical pedicle foramen and no cicatrix of attachment. Bittner's interpretation of the genus, as attached by cementation, is therefore rejected. There is now no authenticated case of cementation attachment in any spiriferide brachiopod, or in any articulate brachiopod outside the Strophomenida. The evolutionary history of cementation, and the affinities of the problematical Thecideacea, are discussed briefly in the light of this discovery.

A geological synopsis of the three main islands of the Tristan da Cunha group is given and their rate of growth by volcanic processes, and their subsequent erosion, are examined in the light of recent radiometric age data. These data, though few as yet, suggest that each island has a “life cycle” consisting of a brief constructional volcanic phase lasting less than 1,000,000 years, followed by an erosional phase of some 20,000,000 years. The possibility that other oceanic islands have had comparable histories is discussed.

Porphyroblastic and alabastrine secondary gypsum from the Middle Carboniferous sequence of Central Vestspitsbergen is described. Evidence is presented to show that the earliest alabastrine gypsum formed from anhydrite by rapid, near-surface, volume for volume hydration, contrary to some previous explanations for similar secondary gypsum elsewhere.