This bore, a recent trial for oil, is situated on the high moorland, rising to just over 1,300 feet above sea-level, in the south-western corner of the Cleveland Hills, where the imposing Jurassic escarpment overlooking the Triassic lowland between Thirsk and Northallerton, suddenly forsakes its northern trend to strike eastwards for about nine miles, before resuming a more northerly course towards Guisborough and the North Sea.

The latest studies of fossil Mammals appear to show that the Upper Pliocene and Pleistocene mammalian faunas of Europe were chiefly immigrants from the Asiatic region (35). The corresponding faunas of Africa seem to have been derived chiefly from the same source (28, 35). The distribution of the stone implements of Palaeolithic Man also can be best explained by supposing that the successive human races who made them started in Asia, and migrated westwards in two divergent streams to Europe and Africa respectively (6). Until the latest phase of the Pleistocene, there cannot have been any direct communication between the men of northern Africa and those of southern Europe. Man, indeed, like the other mammals seems to have originated in the Asiatic region.

Experiments in the stream trough of the Physiographical Laboratory (1) of the Department of Geography at Cambridge had proceeded far enough, before the laboratory was closed for the remainder of the war, for some of the results to be described. These initial experiments were planned so as to isolate for study certain factors in stream action, such as the influence of load on gradient. When possible the behaviour of the little model streams was compared with that of full scale streams and rivers. This comparison seemed to throw some light on the development of certain features associated with flood plains, in particular, river terraces formed without change of sea-level.

There are unfortunately few graptolites that have retained their original chitinous periderm;when these are preserved in rocks of suitable composition they may be isolated from the matrix, and having escaped distortion, may then be studied more or less in their original condition, and much of our knowledge concerning the structure shown by this group of fossils has, in recent years, been derived from such specimens;these, since they are preserved more or less in relief, differ greatly in appearance from the film-like fossils which are of far commoner occurrence, and which can rarely be taken at their face value, but require some degree of interpretation before identification is possible. Lapworth and Nicholson both recognized this, and it is much to be deplored that modern palaeontologists too often ignore this necessity for interpretation and take graptolites at their face value, with the result that specimens that are only views of well-known species are described as new species or varieties, and the literature of the subject is again being burdened with a number of names of no scientific value or significance.

Wheelton hind in his Monograph on Carbonicola gave a critical review of what was known about hinge structure in that genus up to 1896; he described and figured the hinge structure in various species of Carbonicola, notably in shells which he referred to C. acuta (Sowerby). Since that time little has been published about hinge structure in Carbonicola. A paper by M. C. March on the structure and relationships of Carbonicola appears only to have been published in abstract (1913): In that, mention was made of the specialization of the ligament and “cardinal plateau” in the hinge line of Carbonicola, the “cardinal plateau” being grooved for the reception of an internal ligament. It was also stated that hinge structure was absent in C. antiqua, poorly represented in C. turgida and similar forms, and most highly developed in C. aquilina.

It is so easy these days to overlook recent advances of science that I venture to draw attention to two particularly important papers on Indian tectonics by W. D. West, published in 1939 and 1936, both carrying self-sufficient maps. The 1939 paper deals with Alpine tectonics displayed in the Shali Window of the Himalayas, north of Simla; its partner, with a recumbent fold and slide in the Nagpur district of Peninsular India.

In all modern textbooks of stratigraphy the fundamental basis of the classification is the division of the rocks of the earth's crust into four great groups, each of which carries a variety of names but all agree in a hard and fast demarcation of the stratigraphical column. Each of these major groups comprises a certain number of systems, as to whose definition there is on the whole general agreement.

Carboniferous.—The Carboniferous rocks in the bore have a thickness of 2,443 feet, and extend from 3,840 to 6,283 feet.

The genus Hartwellia was founded by the late Dr. F. L. Kitchin (1926) for the reception of the well-known species from the Hartwell Clay which J. de C. Sowerby (1845, pl. Dcxlv, figs. 4, 5) had figured under the name Astarte hartwellensis. Kitchin was able to study specimens in which the hinge had been very clearly prepared and published excellent figures and a very detailed description of the internal as well as of the external characters of the shell.

During field work in 1938 and 1939 some new facts were discovered about the extent of the Hessle Boulder Clay in Northern Norfolk;also a flint core was found in this deposit in the coast section near Happisburgh. As this boulder clay has not been generally recognized so far south-east as Happisburgh, its main characteristics and known geographical extent in the district will be described.

The following descriptions are based on specimens recently collected in the Ordovician rocks of the Girvan area by Mr. James L. Begg and Mr. R. Tripp, and are all new species of interest.

The great volume of extrusive rocks which has accumulated during and since the Tertiary period is one of the most important geological features of East Africa, and one which various people have related to the formation of the Rift Valley System.

The Upper Palaeozoic rocks at Wickwar pass eastwards below Mesozoic strata, but about half a mile farther to the east the pre-Triassic surface is laid bare in places in the floor of the Little Avon River for a distance of 1,300 yards between Stmt Bridge and a point some 360 yards below Horse Bridge. The rocks found here are of Silurian age. Exposures are small and discontinuous since the stream has covered the valley floor with its own deposits and only at intervals does it flow on, or cut laterally into the solid rock. Moreover, the base of the Trias, which is nowhere many feet above the thalweg, sinks twice below stream level, dividing the Silurian outcrop into three inliers. The first two, conveniently styled the northern and southern Sturt Bridge Inliers, are separated by only 40 yards of Triassic deposits, but between the more northerly of these and the Horse Bridge Inlier 330 yards of Triassic rocks intervene.

This paper is an endeavour to demonstrate a development in the fringe of the Trinucleidae, which attained its acme in the Upper Ashgillian as exemplified by the Girvan species Tretaspis cerioides (Angelin) var. sortita Reed.

The subject of stratigraphical classification and nomenclature has given rise to much controversy in the literature.

The deformation of fossils in slates has been studied by many investigators, generally with a view to obtaining data on the strain to which the enclosing rock has been subjected. In the examples previously dealt with it has been necessary to assume an arbitrary length for one of the three principal axes of strain, since the absolute dimensions of the fossils before deformation were unknown. With graptolites, however, the spacing of thecae is a specific characteristic, and, since under favourable circumstances the species of a deformed specimen may be determined by a palaeontologist familiar with the graptolite faunas of a district, comparison of the thecal spacing with that normally characteristic of the species can give a measure of the deformation in absolute units. In some instances generic determination may be sufficient for the purpose. Furthermore, since graptolite rhabdosomes are delicate structures it is reasonable to assume that the amount of deformation they indicate closely approximates to that for the rock matrix as a whole, whereas it is doubtful if such an assumption can be made with more massive fossils. Unfortunately, however, graptolites are so thin that they afford practically only a two-dimensional picture, although it is possible to obtain some data from cross-sections.

The line of demarcation between the Pliocene and the Pleistocene systems is of more importance than would at first sight appear, if for no other reason than because when stratigraphers and palaeontologists are forced by one consideration or another to use the system in preference to the stage names it is often impossible to gather the actual age which they attribute to the deposit or fauna which they are describing. This paper aims at explaining my own point of view, by which I hope to incline adverse scientific opinion towards a definite predilection for the division which I myself favour. Perhaps this may eventually lead to a pronouncement on the question by an authoritative international committee.

When describing the Scottish species Poteriocrinus scotocarbonarius, doubts were expressed about the propriety of assigning it to Poteriocrinus (Wright, 1937, p. 402, 1939–40, p. 17). Before creating a new genus, however, it was considered desirable to make an examination of one of the chief figured specimens of the genotype species P. crassus Miller and to compare it with P. plicatus Austin. Up to the present it has not been possible to do this, and such an outcome seems unlikely for some time to come. In view of the great amount of work that has been done on this and allied genera in recent years, it is now reasonably certain that our Scottish forms are quite distinct from any English or American species or genera hitherto described. Hence the new genus Rhabdocrinus now proposed. The name Poteriocrinus is now discarded in favour of the original Poteriocrinites (Bassler, 1938, Moore and Laudon, 1943). The genotype species was described by Miller in 1821. The specimen illustrated by him as fig. 1 on the plate opposite p. 69 is intended to portray a complete cup apparently from the right posterior side. It has a few columnals attached. According to this figure the radials have horseshoe-shaped facets. The Austins state that this figure is a restoration, and they give an illustration of the same specimen from the same position (Austin, T. and T., 1843–7, pi. 8, fig. 3c, p. 74). Here also the radial facets are not well shown. There is accordingly still a slight doubt regarding these structures on this specimen. On Miller's plate, however, are several figures of detached radials and on the plate opposite p. 67 is a diagrammatic representation of the complete cup of P. crassus. All these figures show radials with horseshoe-shaped facets and a distinct articulating cross ridge, the facets themselves only occupying part of the upper surface of the radials. This type of structure is taken as typical of the genus Poteriocrinites. In the new genus now proposed the facets are quite different in shape and occupy nearly all the upper surfaces of the radials with no trace whatsoever of a cross ridge. The pattern of the surfaces in fact consists of a series of fine crenulations or striations which cross the facets in a transverse direction, i.e. from front to back. In addition, some facets are characterized by little pustules and prominences which are more commonly observed near the centre and towards the back or interior surface of the facets. These features constitute the chief distinguishing character of the new genus. As to the family to which Rhabdocrinus should be assigned, it clearly does not belong to the Poteriocrinitidae as now defined (Moore and Laudon, 1943, p. 54, fig. 5), and since it is impossible under prevailing conditions to trace any known family to which it can be referred, the matter is left open at present.

The two Palaeozoic ranges, the Caledonian and the Hercynian, were comparable in size with the Alps. In his chapter on the European Altaids, F. E. Suess1 says “Recent investigations have brought evidence that the original Variscan mountain chain of which now only scanty remains are left, was once not inferior in size and extension to the Alps to-day”. The remains of both ranges are now at a low level, and it was for some time tacitly accepted that that low level was due to denudation through the long period since they were formed. That low level is not, however, consistent with isostatic theory. Isostatic theory requires that a mountain must have strong roots immersed in a heavier plastic medium so that in effect the chain and its roots float “hydrostatically” in that medium. Accordingly if a layer h km. thick and density p is removed from the top of the range, the level of the range will fall by h (1 − /σ) where σ is the density of the plastic medium. If p = 2·6 for granite, and σ = 2·85 for the intermediate layer, the level will fall by − km.

Nowhere in Yugoslavia has the science of geology progressed more than in Croatia. This statement applies not so much to the period between 1918–1941 as to the years before 1914 when Croatia was a part of the Austro-Hungarian Empire.