A preliminary account of the subject of this paper was given before Section H of the British Association at the Oxford meeting in 1926 (1, 2).

Zoarium free, unilaminate, the back divided by somewhat wavy, shallow, slightly diverging furrows into long narrow strips which correspond with the lines of zoœeia; these strips are occasionally crossed by very shallow depressions or furrows corresponding to the boundaries of individual zoœcia.

Phonolite lava from the Viejo and Teide volcanoes show a wide variation in flow morphology, from viscous, spoon-shaped lavas to thin flows more than 8km long that often show well developed lava channels. The apparent fluidity of these lavas is considered to be largely due to their strongly alkaline character.

In the Geological Magazine, August, 1904, pp. 392–403, Dr. Wheelton Hind describes the Lower Culm beds of North Devon and assigns them to the ‘Pendleside’ series.

From the original paper dealing with that series I gather that in the North of England the ‘Pendleside’ beds lie above the uppermost zone of the Carboniferous Limestone, and are the equivalents of the Millstone Grit of the South Wales and Mendip areas. Dr. Hind's contention is, then, that the Lower Culm of North Devon was laid down at a time subsequent to the deposition of the whole of the Carboniferous Limestone of the Mendips and South Wales.

Last summer I had the pleasure of passing a fortnight in the Channel Islands under the guidance of my friend the Rev. E. Hill, who has done so much to elucidate their geology. During our short visit to Sark we spent some hours in the beautiful little cove called Port du Moulin, examining the interesting sections of the hornblende-schist and underlying gneissic rocks. I was wandering on the beach looking at the wave-worn boulders which afford most interesting studies of the structure of this crystalline series, when my eye was attracted by one which differed much from the rest, and resembled a dark-coloured serpentine of a slightly exceptional character. With some difficulty, owing to its form, I detached a tolerable specimen, and on examining the fresher surface, felt convinced that I had found a rock composed chiefly of an altered olivine and a silvery talc-like mineral.

The genus Cheirurus offers an interesting study in evolution. Barrande, in his monumental work on the Silurian System of Bohemia, drew up a classification of the genus based principally on the character of the pleural grooves. Thus he divided the species into two sections—

The discussion by Professor Gregory in the February GeologicalMagazine of certain ridges of glacial deposits in various widely separated areas seems to call for some comment. I am not familiar with all the examples classified by Professor Gregory any more than he is, but a couple of examples visited by him, and that I have examined many times, may serve as tests of his trustworthiness as a field observer in Glacial Geology and his competence as a commentator upon the observations of others.

The greatest extent of the displacement of the earth's centre of gravity, and consequently the greatest rise of the ocean resulting from that displacement, would of course occur at the time of maximum glaciation, when the ice would be all on one hemisphere. But owing to the following circumstance, a still greater rise than that resulting from the displacement of the earth's centre of gravity alone might take place at some considerable time, either before or after the period of maximum glaciation.

On hearing that Mr. G. E. Dibley, F.G.S., had exhibited at the June meeting of the Geologists' Association some test-plates of Marsupites from the Chalk of a new road near Russell Hill, I made inquiries of him, and he most kindly told me the particular locality where he and others had obtained these fossils. As the place was within an easy walk of my home, I visited it, in company with the younger members of my family, on an evening in June, and found, as Mr. Dibley had told me, that the greater part of the Chalk had been refilled into the sewer-trench, and the residue had been spread over the roadway and was now partly trodden down by the traffic. We patiently broke a number of the remaining blocks of chalk, and, in spite of the fact that Mr. Dibley had already carefully worked at the place, succeeded in finding not only a couple of plates of Marsupites with Echinocorys scutatus, etc., but also some smaller inconspicuous plates which, when cleaned from the matrix, proved to be test-plates of the unstalked, free-swimming crinoid, Uintacrinus, Grinnell. These showed the existence at this place of the lower portion of the Marsupites-zone, which has been designated by Dr. Rowe the “Band of Uintacrinus.”

So much confusion has occurred in the past over the identification of the genera which we have been discussing, that a list of some figured species from the Jurassic rocks, arranged in their proper sub-genera, may be useful. The only previous attempt at a list of this sort, so far as I am aware, is that by Professor Rollier, who was only able to enumerate five species. He called all these Beushausenia, but two are not Beushausenias but true Parallelodons, while a third belongs to a different genus.

While working for several years on Palaeozoic Bryozoa with the aim of establishing the Palaeozoic stratigraphy of the Altai Mountains on the basis of the Bryozoan faunas, I have always been aware of a great contradiction. The works of American authors showed clearly that the stratigraphic importance of the Bryozoa is not inferior to that of any other group of fossils, whilst in the works of newer European authors the Palaeozoic Bryozoa were not only deprived of any significant rôle, but often even quite ignored. Owing to this, there arose a question whether the Palaeozoic Bryozoa have a universal distribution like, for instance, the Brachiopoda; or whether there is in North America a special Bryozoan fauna of stratigraphic importance locally, but absent from other parts of the globe. The study of the Siberian Palaeozoic Bryozoa showed a number of forms so far known only from North America, and this suggested that the apparent absence of “American” forms in the other parts of the globe is owing to the lack of intensive study given to the Palaeozoic Bryozoan faunas outside North America. Through the kindness of Dr. Nalivkin, who handed over to me several Bryozoa collected by him in the Middle Devonian of Germany, I was able to confirm this suggestion and I decided to examine, if possible, the existing collections of Palaeozoic Bryozoa of Europe. This appeared the more necessary because, although Palaeozoic Bryozoa were originally described by European authors, yet the species described by them were quite ignored by later American writers. Clearly then, if a comparison of the European with the American Palaeozoic Bryozoa were made, it would be likely that the trivial names of some American species would be replaced by the prior trivial names of European species. To make this comparison, I visited during the winter of 1928–1929 some of the most important museums of Europe, in which I could find either the type specimens of the European Bryozoa, or merely rich collections of topotypes. A revision of the material contained in the museums of Berlin, Munich, Bonn, Prague, Paris and London wholly confirmed my view, namely, that the “American” forms of Palaeozoic Bryozoa were universally distributed, but hitherto had been described and figured, often quite incorrectly, as distinct genera.

It is possible, from study of twinned calcite grains in a thin section of marble, to locate the most probable positions of the applied stresses likely to have caused the twinning. By this means inferences may be drawn as to the stress system operative during the late stage deformation of the marble.

Marble outcrops over an area of about 5 square miles, in the Tomintoul region of the Scottish Highlands, have been investigated. It has been found that a consistent stress pattern exists for the area as a whole. The calcite twinning can best be explained by a N.E.–S.W. compression applied normal to the trend of the regional fold axis, followed by a mild N.–S. squeeze.

We now come to the second o rder of the Trilobita, which Beecher (loc. cit.) calls the Opisthoparia. In common with the third order, the Proparia, compound paired eyes are usually present, and these are invariably situated on the free cheeks, which form part of the dorsal surface of the head-shield.

The Swedish Magellanic Expedition spent some time in the Falkland Islands before proceeding to Tierra del Fuego, where important work is being carried on. The writer utilised his stay in the Falklands to study the geology and collect fossils. The following is a brief note of the work there.