In this specimen one valve (the left) and a part of the dorsal region of the other, remain visible; the rest of the right valve being bent down, broken, and imbedded in the matrix. This is a finely micaceous, non-calcareous, grey mudstone, weathering ferruginous towards one edge, which probably abutted on a crack open to water and atmosphere.

The fossil, in the grey portion is darker than the matrix, and fairly represents the test of half of the carapace, with only a very thin lamina wanting, a broken edge of which is traceable (with a lens) near the ventral margin. This left valve measures 9·2 by 7·4 mm. It is subcircular, more boldly curved on the ventral than on the posterior margin, whilst the front margin is somewhat truncate, having a nearly straight edge from above downwards before it bends round into the ventral curve.

In the GeologicalMagazine for 1877, Dec. II. Vol. IV., pp. 410, 456. there is an article on the “Geology of the Isle of Man,” by Mr. Henry H. Howorth, to which I desire to call attention. Most geologists are aware that the late Rev. Joseph G. Cumming, M.A., F.G.S., wrote a work entitled “The Isle of Man,” in 1848, and that it contains a geological description of the island. In this work, and in a papaer by the same author, published in the “Journal of the Geological Society” for 1846, vol. ii. p. 317, there is a minute description of the Carboniderous formation developed at the south of the island, near Castleton, illustrated by maps and sections.

Two valuable pamphlets on Jurassic Ammonites have lately appeared. One of these is entitled “Cephalopodes nouveaux ou peu connus des Étages jurassiques de Normandie, par Louis Brasil.” This author, who has paid very considerable and successful attention to the Jurassic rocks in the neighbourhood of Caen, describes and figures (there are four plates) nineteen new species of Ammonites belonging to fourteen genera, viz.: Lytoceras, Phylloceras, Catulloceras, Zurcheria, Dorsetensia, Bajocia, Pæcilomorphus, Hammatoceras, Erycites, Oppelia, Cadomoceras, Strigoceras, Cosmoceras, Œcotyphius. Of these genera one is new, namely, Bajocia, founded on an unique specimen; and it must be confessed that the example is sufficiently distinct in every way to warrant this treatment. Although the author does not say so, it is evident the genus belongs to the subfamily Sonniniæ and M. Brasil practically admits as much when he states that it is very near to Dorsetensia. He further says that he considers it to be a branch from Haplopleuroceras, whose representatives have lost not only the two rows of spines, but even the keel and the furrows. We find ourselves unable to agree with this opinion, because the periphery is rounded and flattened; in our experience the keel and furrows do not disappear without leaving some trace of their former existence on the configuration of the periphery. We agree with the author that Bajocia is near to Dorsetensia, and we are inclined to think it is a late-surviving example of the stock whence Dorsetensia originated, and a “cousin” of Zurcheria.

Those who have carefully studied the crystalline schists cannot fail to have noticed that a community of structure—a sort of family likeness—prevails throughout any one group of rocks, while those which occur apparently at different horizons exhibit dissimilar structures. Thus the marbles associated with any group of crystalline schists are coarse or fine in grain, according to the structure of the latter. But to this rule exceptions appear, at first sight, not infrequent. For instance, in the Alps, we find not uncommonly, in that group of schists which seems to occupy the highest position, marbles which present an abnormally compact aspect. On closer examination they prove indeed to be crystalline in structure, but the crystals seem so small, the general structure so compact, that until we find them graduating into typical mica or other schists, we can hardly feel satisfied we are not being duped by infolded limestones of Mesozoic or Palæozoic age.

The section exposing this stratum was discovered during an excursion made last June by Mr. W. Hill, F.G.S., and the author. It occurs in a quarry near West Row Ferry, about two miles west of Mildenhall;here a band of red marly chalk is seen near the entrance, dipping westward at a low angle, hut soon becoming horizontal and running along the whole face of the quarry, till it is cut off by a fault, which brings up lower beds on the southern side.

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.

This work was undertaken in an attempt to assess the significance of minor variations in composition and properties of sand samples collected from the same locality and derived from a common source.

Lower Carboniferous strata are shown to be absent from the Amazon basin and Ghana, the Bermejo series of Bolivia is Permo-Triassic, the Sekondi series of Ghana does not include glacial deposits and may prove to be Devonian, early Carboniferous glaciation is unknown in Africa and restricted to Argentina in South America. In the light of these interpretations the extent to which late Carboniferous glaciation affected northern South America and Africa is briefly reviewed and shown to conflict with the reconstructions by L. C. King (1958). The non-glaciation of Africa and South America north of at least latitude 25 degrees South during early Carboniferous times is regarded as proving that these areas did not pass through the south polar region at that time. The known distribution of early and late Carboniferous glacial deposits is considered in relation to continental drift and movement can only have been westwards during the Carboniferous period.

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.

In 1908 Dr. Rowe published an account of the Chalk of the Isle of Wight with a zonal map in which the zone of Belemnitella mucronata was shown as entirely absent at some points but generally present in substantial thickness. At the two ends of the island actual measurements were made, of 150 feet at Culver Down and 475 feet at the Needles. How much of the latter thickness was measured in the cliffs and how much is made up of somewhat less satisfactory measurements at low tide on weed-covered reefs is not clear, but at any rate there must be well over 300 feet in the cliffs. This figure is sufficient to show how great a ravining of the pre-Tertiary surface of the chalk would be required for the repeated disappearances of the zone as mapped. It seems justifiable to pay some critical attention to the evidence on which such a state of things is alleged.

The scientific proceedings of the Eighteenth Session of the International Geological Congress included twelve series of Sectional Meetings, open meetings of the Association of African Geological Surveys, and of the International Paleontological Union, and special discussions on the Geology and Mineralogy of Clays. Summaries of these Sectional and other meetings, prepared by their officers, are published in advance in the full Report of the Session.