Several aspects of the Queensland serpentinites are discussed, including the significance of a suite of serpentinite-breccias, the formation of antigorite, and the general problem of serpentinization and mode of emplacement of the ultramafic rocks.

The cross-bedding of the Lower Cretaceous sands between Leighton Buzzard and Hunstanton has been studied. This paper describes new evidence which throws further light on the depositional environment and palaeogeography of these sediments.

Both cross-bedding and grain size distribution were investigated in detail in the Woburn Sands (Aptian). These beds lie between Cambridge and Leighton Buzzard (Cameron, in Kirkaldy, 1939, p. 407), and are the youngest “;Lower Greensand” of East Anglia. Rather less attention has been paid to the pre-Barremian Sandringham Sands (Downham to Hunstanton). Unfortunately, the Carstone of Hunstanton shows no cross-bedding.

Seven species of ammonites from the Lungma Limestone of Tibet are described and figured. The assemblage is Middle Bajocian, of the Sowerbyi and Sauzei Zones, and possible also Humphriesianum Zone, and indicates that the formation is condensed. Its affinities are chiefly with European faunas, but it has one species in common with the Pamirs and another with Western Australia.

A technique for roughly evaluating the chemical variability within a suite of rocks is described and discussed in relation to the composition of the granite and quartzite of N. W. Donegal. The accuracy of this method is compared with more expensive chemical analysis.

A study of the structure and petrography of the limestones exposed at Hall Hill, in Bowland, enables the geometry of part of a Carboniferous reef knoll to be defined. The main features are a central mound-like core of unbedded, poorly fossiliferous calcite mudstone and a peripheral area of bedded calcite mudstones with original, depositional dips. Thick, well-bedded coarse crinoidal limestones were subsequently bedded over the underlying knoll.

In the pelitic rocks of this classical section it appears that, chemically, a Fe2O3: Al2O3 ratio of about 0·40 is critical for the formation of chloritoid or staurolite. With this ratio both minerals are possible, but if the value exceeds a figure somewhere between 0·47 and 0·55 staurolite cannot form, a reddish-brown biotite appearing instead. Physically, a certain minimum temperature is necessary before staurolite can appear and below this chloritoid is the equilibrium phase.

The growth of the rhabdosome from the initial prosicula is described for two species of Monograptus. Sections of the metasicula have shown the nature of the “Stillstandsgürtel” first described by Kraft, and in both species evidence about the structure of the interthecal septum is given. It appears that there are two forms of Monograptus dubius which have the same external appearance but differ in the details of early development.