A review is offered of some of the conclusions reached by Teall and his Survey colleagues on the Lewisian Complex of the North-West Highlands, especially such as have been strengthened by recent work by Sutton and Watson. In other directions support is given to Peach and Gunn's view that the Loch Maree sediments are later than the Scourie Dykes and not, as dough tentatively suggested, intruded by sills fed from these dykes; also new hypotheses are advanced concerning Laxfordian folding of the Scourie Dykes at Loch Maree, and Caledonian thrusting of Assynt type of Lewisian over Laxford type at Durness.

Preliminary observations indicate that the rhythmically varied layers of ultrabasic rock in Rhum form part of a layered intrusion built up from below rather than a series of separate injections.

An account is given of a new minor structural feature recently found in the Forest Marble of Bladon, Oxfordshire, resembling Pit and Mound structure, and various suggestions as to its mode of origin are discussed.

The stages of progressive thermal metamorphism of siliceous carbonate sediments covering mineral assemblages revealed in the highest grades of alteration were first delineated by Bowen (1940) in a paper which presented an illuminating systematic treatment of the whole subject. In his account the successive stages in the metamorphism of siliceous limestones and dolomites were, in general, linked with a series of reactions of increasing decarbonation in which thirteen steps were traced, involving the appearance of ten distinct mineral phases. With certain reservations these phases could be accepted as indicators of a temperature grade of metamorphism. Investigations carried out since that time have served to confirm the general validity of the scheme set out which thus brings law and order into a field of metamorphism characterized by considerable mineralogical and petrographical complexity.

The possibility of interaction between the alkalies in cement and flint and chalcedony has made it necessary to investigate the constitution of these minerals. It had always been thought that these minerals were a mixture of quartz and opal, but experiments have led to the belief that this is not true and that the minerals are composed of a quartz network with a large number of micropores.

In the outer zone of the Sutherland Migmatite Complex, four-inch garnets are developed in “veins” in garnetiferous rocks which, adjacent to the “veins”, are devoid of garnet. The redistribution of material has been brought about by activity along certain privileged paths. Comparison is made with the gigantic 3-ft. garnets of the Adirondacks.

Neglect of the oldest and most useful theory of scale models in geology. Its fundamental psychological value for a correct mental picture of the earth's larger aspects.

The exact theory made more comprehensible. Its application in the domain of experimental tectonics improved upon.

The Maestrichtian is considered an independent stage younger than and equal in rank to the Senonian stage; in its type-area it includes, besides the Maestricht Tuff, such older formations as the Chalk of Ciply and of Spiennes, the Kunrade Limestone, upper beds of the Gulpen Chalk, and even some part of the Hervian Greensands. The zone of Pachydiscus egertoni forms the base of the Maestrichtian stage.

In its type locality the Campanian stage includes the zone of Bostrychoceras polyplocum; at the same time its uppermost beds are at any rate not older than the uppermost beds of the Senonian stage in its type area. The zone of B. polyplocum thus forms a part of the Senonian stage.

The true Belemnella lanceolata (Schloth.) is restricted to the Trimingham Chalk. Belemnitella ex. gr. mucronata (including “Belemnites lanceolatus” von Sharpe and Blackmore non Schloth.) are, on the contrary, all but confined to the Norwich Chalk and older beds of the English Upper Chalk. Accordingly, a new zonal name “Zone of Belemnella lanceolata” is recommended for the Trimingham Chalk, and the zone of Belemnitella mucronata should, in the opinion of the writer, be restricted to beds older than the Trimingham Chalk.

The Trimingham Chalk is assigned to the Lower Maestrichtian, while the Norwich Chalk represents the Upper Campanian (including the B. polyplocum zone).

The Carboniferous ostracod Rhombina Jones and Kirkby is shown to have been misinterpreted. The genus is redescribed, a new family is erected for its reception, and a new genus, Palaeophilomedes, proposed as a second member of this family.

Menevia and Psilocephalus are names in current use for two genera of Trilobites respectively occurring in the Middle Cambrian and Tremadoc rocks of Wales; both are now known to be invalid, having previously been used for other animals, and the new names Meneviella and Psilocephalina are proposed to replace them.

A description is given of nodules of copper-ore (ferruginous chalcocite) occurring in the Lower Torridonian rocks (Diabaig beds) at Clachtoll, N.W. of Lochinver, Sutherland.