The field relationships between the Armorican granite of North-West Jersey and the Precambrian sediments in the Le Pulec and L'Etacq areas are described together with the petrography of the contact rocks. Trace-element determinations on rocks from two traverses across contacts in the area, and upon control specimens of granite and sediments supplement the petrography. The mechanism of granite emplacement in this area is discussed.

The pre-Cambrian rocks of the Southern portion of Southampton Island are composed of acid gneisses of very variable character containing a few, commonly zoned, xenoliths. The petrography of both is described; eight new analyses are given, and the probable origin of several of these xenoliths is suggested.

A preliminary account of the geological results of an expedition to the volcanic massif of Kilimanjaro is given. The structure and succession at each of the main eruptive centres is described. The probable ages of volcanicity are discussed.

The Basement Complex rocks of the Northern Red Sea Hills, Sudan, are believed to be pre-Cambrian in age. They can be divided into three major sedimentary and volcanic divisions, with four main periods of igneous intrusion. The succession proposed by the author is as follows:—

Red granite.

Injection granite.

Awat series.

(Unconformity with folding, thrusting, and cleavage.)

Basic intrusive phase.

Nafirdeib series.

(Unconformity with folding, and regional metamorphism.)

Primitive system {Acid Gneiss (intrusive). Schists and Gneiss.

The history of ideas on boudinage is outlined, and observations in Perthshire are described. Some implications of the “necking hypothesis” are examined.

A series of terraces in the Dale Valley south of Dalsfjord has been mapped, and heights have been established. The results have been analysed into a sequence of stages, and compared with general conclusions advanced by J. Rekstad and F. Nansen, on the isostatic displacement of postglacial terraces in Norway.

Recumbent shear folds and their related structures in the Mylor Slates are briefly described. It is concluded that folding has been produced by subhorizontal shearing stresses acting in a northwesterly or south-easterly direction.

A petrochemical study of the Pen-y-Gader dolerite has been made. The intrusion produced a mild thermal metamorphism in the country sediments and then a late-stage metasomatism affecting the dolerite as well as producing spilosites and adinoles in the country rocks. The main metasomatism involved the introduction of sodium with small amounts of boron and fluorine into the sediments. The range of activity beneath the intrusion was governed by the porosity of the sediments affected, coarsegrained bands being followed for greater distances. The chemical and mineralogical variations within the dolerite have also been compared with those observed in certain of its ophitic neighbours.

Heliolites caespitosa Salter (1873) is shown to be identical with Heliolites parvistella Roemer (1861) var. intricate Lindström (1899). The varietal name must, therefore, become caespitosa. Evidence is brought forward to suggest that the two varieties of this coral are the results of differing environments.

At various localities along the contact of the Moine Series with the supposed Lewisian Inlier at Glen Strathfarrar structures resembling those of a conglomerate have been described. New evidence is brought forward which suggests that these structures are of tectonic origin and were produced by the disruption of competent bands in an incompetent matrix.

The occurrence of a goniatite horizon in the Yoredale Series exposed on Ingleborough can now be recorded. The goniatite, Neoglyphioceras cf. spirale (Phillips) was found in shales underlying a limestone which may probably be the Five Yard.

The discovery of a hitherto unrecorded non-marine lamellibranch fauna from the Tillery Vein of Monmouthshire indicates that this coal represents a horizon at, or near, the junction of the Phillipsii and Tenuis Zones. The characteristics of the seam in a small portion of the North Crop of the South Wales Coalfield are described in an attempt to account for the limited occurrence of these shells.

The major septa of clisiophyllid corals originate deep down in the calyx and grow upwards, fanning out towards both the axis and the periphery of the coral. The minor septa originate high up near the rim of the calyx and appear in pairs one septum being inserted on either side of each new major septum. The insertion of minor septa on both sides of a new major septum complicates the development of the subsequent major septum at the fossula.

For certain unconsolidated sediments there is a linear relationship between the arithmetic mean size and the “grading factor”, and sediments with an average particle size of 0·2 mm. show the maximum degree of sorting. An hypothesis has been developed to explain this relationship in terms of the environment of deposition.

The holotype of Brancoceras enniskillense Foord, 1903, is shown to be a specimen of Beyrichoceras excavatum (Phillips), 1836, the suture line of which has been misinterpreted. It is associated with Beyrichoceras castletonense (Bisat), indicating the presence of the Upper B2 subzone in the Carboniferous Limestone, of Blacklion.

Nine species (eight new) of holothurian spicules are recorded from the Oxford Clay (cordatum zone) of Redcliff, near Weymouth on the Dorset coast. The new species are described and named and the significance of a close association of Rhabdotites and Theelia is discussed. Previous records of holothurian spicules from British strata are reviewed.

The cephalic characters which the post-Cambrian trilobite families Encrinuridae, Pliomeridae, Cheiruridae, and Phacopidae have in common are discussed, together with others which illustrate the distinctness of the Phacopidae. The importance of growth-rate studies is emphasized, particularly with reference to the frontal lobe of the glabella. The Calymenidae share most of the features common to the Cheiruracea and Phacopacea, and are considered to be closely related to them, and the Odontppleuridae also share certain features. The possibly neotenous origin of the Cheiruracea and Phacopacea is discussed.

The Old Red Sandstone lavas of the Perthshire Sidlaws are basalts with some andesite-basalts, andesites, and rare trachyandesite. The basalts comprise chiefly olivine-bearing flows that include feldspar-phyric and aphyric varieties; olivine-free basalts with two pyroxenes are of restricted distribution.

The significance of augite textures and their relationship to augite content in the basalts is discussed.

The lava pile is apparently composed of interdigitating lenticular flows that vary from a few feet up to about 80 feet in thickness.

Unlike most other Scottish Old Red Sandstone lava suites the Sidlaw suite is fairly fresh and, like the Eastern Forfarshire lavas, it is relatively basic.

Li, Rb, and Cs were determined spectrographically in twenty-eight trilobites, two xiphosurida, four insects, four Crustacea, and six brachiopods. The sediments associated with fifteen trilobites were also analysed. Compared with igneous and sedimentary rocks, the trilobites were characteristically enriched in cesium relative to rubidium and potassium. Thus, the K\Rb ratios were normal, but the Rb\Cs ratios were anomalously low. The evidence is considered to favour the view that cesium has been preferentially concentrated by trilobites during growth. The matrices had Rb\Cs ratios similar to normal sedimentary rocks.

The Moine Thrust Zone in the Lochcarron and Coulin Forest areas contains numerous small scale folds which plunge eastwards. The axial planes of these folds are inclined towards the north or south so that no regional directional translation of the rocks can be postulated from these structures, whose symmetry as a whole is orthorhombic. The folds are considered to have resulted from local lateral extension and concomitant compression of laminated rocks involved in the thrusting.