The geology of the Lleyn peninsula has from time to time attracted the attention of geologists, and several workers have added much to our knowledge of this district; but their researches have been mainly confined to (1) the strip of ancient rocks (usually assigned to the pre-Cambrian) in the west between Porth Dinlleyn and Bardsey Island, and (2) the igneous rocks lying in the Ordovician ground which occupies the eastern and larger portion of the peninsula. Thus the Ordovician sedimentary rocks have largely escaped attention, a result probably also due to their monotony, to the rarity of fossiliferous localities, and to the great extent to which the beds are concealed beneath accumulations of drift.

To those students interested in the palæontology of Maryland, United States, it may be welcome intelligence to know that the “John Finch Collection” of Tertiary Mollusca from that State, including some of the type-specimens figured and described by Thomas Say in 1824, is in the possession of the British Museum. This fact has only recently been recognized through the examination of certain documentary evidence connected with the history of the fossil invertebrate collections contained in that institution.

The publication of the Annual Reports for 1898 and 1899 of the Cape Geological Commission, coupled with the recent account of the geology of the Transvaal Colony by Dr. Molengraaff, and of which a short abstract has appeared in this Magazine, adds considerably to the knowledge of South African geology. The succession of the rock formations at the Cape has been constantly used as a basis of classification for the rock systems south of the Zambesi. In his recent paper Dr. Molengraaff correlates the formations of the Transvaal Colony with those met with in the south-eastern provinces of Cape Colony, and emphasizes the fact that the three stages of the Pretoria, Dolomite, and Black Reef series of the Transvaal Colony may be compared with the Witteberg, Bokkeveld, and Table Mountain Sandstone series of the Cape. It may therefore be of service to show on what grounds this supposed correlation is based. To do this the succession at the Cape of the formations below the Beaufort Beds in the typical region of the south-eastern province will first be given.

When Dr. Woodward asked me a few months ago to review some pamphlets on early Man and his remains, I very reluctantly promised to do so, because I felt that if I were to be frank and sincere I must speak of some recent developments of the study in unsympathetic terms, which would not be welcome in some quarters. I little expected, however, that I should have been overwhelmed by such a shower of peppercorns as I find on my return from Italy was the case in the September number of the Geological Magazine.

Having undertaken to explain the geology of the Cheddar gorge to the Cotteswold Naturalists' Field Club at one of their field-meetings this Summer, I thought I should do so more intelligently if I first acquired a practical knowledge of my subject. I accordingly paid a preliminary visit to Cheddar. There were two chief questions to be investigated: (1) the origin of the gorge, and (2) the cause of its serpentine, or rather zigzag, course. The former inquiry had been answered in four different ways. There had been geologists who held that the valley had been excavated by the waves of the sea. A second school taught that it had been produced by a dislocation, splitting the rocks asunder. The third theory regarded it as a valley of erosion, excavated in the ordinary way by a river on the surface. A fourth explanation placed the river underground, and maintained that the glen had originally been a long winding cavern, the roof of which had subsequently fallen in.

That the Upper Cretaceous deposits overlap those of the Lower Cretaceous series, and extend over much larger areas throughout the whole of western and central Europe, are facts which have long been familiar to all European geologists. There has, however, been a tendency, especially in France, to imagine that the subsidence to which the overlap is due took place at one particular epoch, namely, the Cenomanian, and that this subsidence was so rapid and profound that it caused the Upper Cretaceous Series to be sharply marked off from the subjacent strata by the so-called ‘Cenomanian transgression.’

Nearly ten years ago I proposed the term ‘hemera.’ The term is coming into use; but, so far as I am aware, in the majority of cases it is greatly misunderstood. From this cause arise objections as to its use, such objections being based on the misconception that the hemera is a subdivision of a zone. It is nothing of the kind.

In recent work on the laws of river-dynamics an important part has been taken by members of the Cotteswold Naturalists' Field Club. Dr. T. S. Ellis, in 1882, announced the suggestive fact that the course of all the eastern tributaries of the Severn between Berkeley and Tewkesbury was directed obliquely up the valley, a discovery which furnished the key to the relative ages of the Severn and the Thames.

For many years Dr. G. F. Matthew, of St. John, New Brunswick, has given much attention to the geology and fossils of the districts lying on or near the north-eastern seaboard of North America, and has closely studied their minute fossils resembling (if not identical with) varieties of small bivalved Entomostraca; and he has published his results from time to time in the scientific periodicals of Canada and the United States.

It would be difficult after the closest investigation to add much to the exhaustive list of species given in the excellent paper on this subject which was read by Mr. Swanston before the Belfast Naturalists Field Club some twenty-five years ago. In that paper reference is made to the classification by the Geological Survey of the rocks of the district, under the general heading of Lower Silurian. Subsequently to the publication of the maps of the area, the information as to the Silurian fauna was greatly extended by the labours of Professor Lapworth and Mr. Swanston, to whom science is so largely indebted. The completion of the one-inch Geological Map of Ireland enabled the revision of work done in the earlier stages of the Survey's existence to be undertaken, and in this revision the North-East Silurians were amongst the first dealt with, and I was detailed to search the most promising localities for fossils, and to zone the beds in which they might occur.

The original specimen (a 878) is in a very perfect condition and comes from the Wenlock Limestone of Dudley. It also belongs to the Fletcher Collection. There is no other specimen of this species in the Woodwardian Museum. Salter calls it “a new square species.”

It is remarkable, considering the enormous development of igneous rocks in South Africa, that so little has been written concerning the features they present in the field or under the microscope. Right away from Cape Town into the tropics, plutonic masses, dykes, and lava-flows interrupt the continuity of the sedimentary deposits with astonishing frequency. Some of these rocks, like the Cape Town granite and dolerite, are probably of pre-Silurian age; others, like the Kimberley lavas, were erupted during the Secondary period: while others, again, like the dykes and lavas of the Zambesi Valley, are probably of late Tertiary or even geologically recent date, as evidenced by the numerous geysers and hot springs which represent the final phase of not long antecedent volcanic activity. They appear to bear the same relation to the volcanoes of Central Africa as the British Tertiary lavas do to those of Iceland.

An occasional visit to a village on the western border of South Staffordshire has given me the opportunity of studying the Triassic deposits around there. Possibly the various sections I have visited are well known to local geologists, although, so far, I have not come across any description of them. One section in particular, I think, must have been overlooked, and this it is now proposed to describe by way of an introduction to the more important remarks which follow from the pen of Dr. A. Smith Woodward.

The Upper Gondwána (Rajmahál Series) beds near Madras are divided into two groups, the lower of which has been named from Sripermatúr, a town 25 miles west-south-west of Madras, and a well-known locality for fossil plants. The group is composed of white and pale buff-coloured shales containing plants, at least 10 feet in thickness, resting upon sandstones, grits, and micaceous sandy shales, at least 15 feet in thickness, whose base is not seen, but which probably rest on the gneiss. Silicified wood occurs in some of the gritty beds. The other fossils occur in the shales, and consist of plant and animal remains. The latter are poor, and comprise two or three indeterminable species of ammonites and several lamellibranch bivalves.

The view expressed in 1882 that the Westleton Beds of Westleton, in Suffolk, form part of the Middle Glacial division of S. V. Wood, jun., was strengthened by observations made at Southwold in 1895, and is supported by sections examined last year near Lowestoft.

The generic and specific names and the horizons are those given by the authors. The numbers in square brackets correspond to those of the Museum register. A list of references and a history of the collections is given at the end. The localities, except where otherwise stated, are in Norfolk.

Since the dawn of early history the question of the existence of a continent beyond the “pillars of Hercules” has occupied the mind of man. Our very earliest records of this mythical land were derived from a narrative which has been handed down to us by Plato. According to it, Solon is said to have visited Sais in Egypt, and there to have heard from priests of the ancient “Empire of Atlantis” and of its overthrow by a convulsion of Nature. This Atlantis was then spoken of as a vast land lying beyond what we now call the Straits of Gibraltar, and it is supposed to have been inhabited by a mighty race of people. Plato's story has called forth quite a flood of literature, not only in ancient times; even within the last score of years many pamphlets and books have been published dealing with this attractive problem. Some authors have sought to discredit the veracity of Plato's assertions, while several, and among them Humboldt and Sir Daniel Wilson, were of opinion that the tale rests on some historic basis. Others, again, have utilised the original story and connected it with their own ideas of a land-bridge stretching right across the Atlantic from Europe to America.

In the collection made by the late Dr. Grindrod, now in the Geological Museum at Oxford, there is a minute species of trilobite, represented by two specimens, obtained from the Dictyonema-shales of the Malverns. This form was referred by Dr. Callaway to Shumardia (Conophrys) Salopiensis, Call.; but a careful study of the two specimens, aided by the removal of a small fragment of shale which partly concealed the more complete example, has shown the distinctness of the trilobite from Shumardia, and from any other genus known to the writer. Owing to the kindness of Professor Sollas I have been enabled to make a thorough examination of the specimens. The preservation is fairly good, but much of the actual test has been lost, and both fossils are largely in the form of internal casts. In the more complete but somewhat smaller example, which may be taken as the type-specimen, the whole trilobite is preserved (Fig. 3); in the second specimen little more than the thorax and pygidium is seen (Fig. 4).