The central position of Leicestershire gives it not only a peculiar relationship in regard to river-drainage, streams radiating from its plateau-frontier on the one hand to the north, flowing into the Humber, and on the other to the south into the Bristol Channel, separated alone by a now comparatively insignificant divide in the neighbourhood of Lutterworth. Also the very fact that this divide is given, by the otherwise lowland character of the tract to the north and south, a barrier-like aspect, renders it highly probable that the flora and fauna in this basin-like area is more or less homogeneous. That it has been uniform in character, no doubt from pre-Glacial times, when doubtless the existing drainage systems (though probably still more ancient fundamentally) received their most recent stamp, having been little modified (except in depth or width) during Glacial or later times. For this purpose we must needs summarize all that is known as to the occurrence of plants or land and fresh water Mollusca in post-Pleistocene alluvial deposits.

Lying at the foot of the Cheviot Hills are deposits of sand and gravel, which, between Wooler on the north and Glanton on the south, cover a considerable area, occupying the greater part of the lower valleys of the Breamish and other tributary streams of the Till. They form mounds and ridges running in different directions, often dividing and reuniting in a very irregular manner. They are indicated, along with deposits at greater altitudes, on the Drift Edition of the Map of the Geological Survey of England (Sheets 109 N. W. and 110 S. W.) as “sands and gravels of Glacial age”. It is for the purpose of describing these accumulations and in some measure elucidating their source and mode of deposition that this paper is written.

When one considers the part Britons have played in exploring and investigating the various desert regions of the world, one is surprised at the relatively small amount of literature that there is in the English language dealing with the phenomena which are peculiar to desert conditions. Many hazy, and even erroneous, ideas are still held with regard to the processes at work and the effects produced by the various agents of denudation.

The great copper-mining district of Southern Spain and Portugal has been studied by several eminent geologists, and the problems presented in the geology of the field and of its ore-deposits have given rise to conflicting opinions. The three most debated points have been the origin of the ore-deposits, the relations of the igneous rocks, and the age of the sedimentary formations. The present paper, the field work for which was carried out during the last summer season, deals in the main with the two latter points, and the writer takes this opportunity of expressing his indebtedness to Professor W. W. Watts and to Dr. C. G. Cullis for their advice and suggestions during the subsequent petrological studies at the Imperial College of Science and Technology, London.

Wind-worn Pebbles are somewhat rare in England, and accordingly it may be of interest to record the occurrence of a deposit of which they from a prominent feature. This has been met with in several quarry-sections at Hill Top, near Bromsgrove in Worcestershire, at about 350 feet above sea-level. I am indebted to Mr. Willcox, the owner of one of the quarries, for Pointing out these Pebbles to me.

The subject of ‘pleochroic halos’ has become endowed with peculiar interest since Professor Joly suggested that they are due to the radio-activity of the inclusions round which they occur. On looking into such petrographical literature as I possess, it appears that very few precise observations have been made regarding these halos, and it has occurred to me, therefore, that some of my own notes on the subject may be of general interest.

The skeleton figured on Plate XII is that of a small Pliosaur, Peloneustes philarchus, Seeley, sp. This specimen was obtained from the Oxford Clay in the neighbourhood of Peterborough by Mr. A. N. Leeds, F.G.S., to whom the British Museum is indebted for a great series of more or less perfect skeletons of many species of Oxford Clay Reptiles, including the beautifully preserved and nearly complete examples of Cryptocleidus oxoniensis and the remains of Cetiosaurus leedsi, now mounted in the Gallery of Fossil Reptiles. So far as I am aware, this is the first skeleton of a Pliosaur that has been mounted so as to show the true form of the body in those reptiles. All the bones belong to a single individual, but the left-hand paddle and the distal portion of the other paddles being wanting, they have been represented by plaster models made from the paddles of another individual, which are exhibited on the floor of the case. The left ischium has been modelled from that of the opposite side.

Being prevented by other work from continuing at present my work on the Danian (Laramie) Dinosaurs of Transylvania, I wish briefly to draw attention to the fact that the Upper Cretaceous Titanosaurus, as known from the Montagne Noire in France and from the Cretaceous formation of Argentina, and perhaps also from East Africa (as already pointed out by Fraas), has nothing to do with the Sauropoda, but belongs to the Trachodontid Orthopods, as proved by the abundant Transylvanian material at my disposal.

During the last few weeks East Yorkshire seems to have been severely dealt with by wind and hail and flood, and in common with the rest of the area the cliffs have suffered. Geologists, however, are able to profit where others lose, and as a result of disasters can obtain useful information in reference to the structure of a district. Perhaps one of the most interesting exposures that has recently been made occurs at the south extremity of North Sea Landing, Flamborough, where a large amount of cliff has recently slid down on the beach.

The following is a preliminary account of the rocks overlying the Lower Old Red Sandstone of the Titterstone Clee Hills, Shrops.

Bryn-y-groes Lode.—About 500 yards east of the Clogau lode, there is a parallel lode which has been worked for copper. Striking 50° east of north, its outcrop may be traced for about 1½ miles; its width is very variable. Chalcopyrite and pyrites and a little gold are present in the quartz. The lode is confined to the Vigra Beds, and running with the beds, it is associated throughout its length with greenstone sills.

Zoœcia roughly elliptical, length ·60 to ·68 mm., width ·36 to ·40 mm., length of area ·36 to ·40 mm., width ·24 to ·28 mm.; they have broad side walls, whose upper surfaces slope slightly to the area; at the foot there is generally a fair amount of external front wall, which often carries its own accessory avicularium or the oœcium of the preceding zoœcium; the walls of adjacent zoœcia are always distinguishable and very often not in contant.

I have already described the granular appearance of glacier ice as seen in polarized light and also the striations on the granules as shown by pencil rubbings. Last summer I succeeded in obtaining exact reproductions, in plaster of Paris, of the ice surface-structure in the upper cave in the Rhone Glacier. These are shown in Figs. 1–3.

In a review of Mr. H. J. L. Beadnell's important Memoir on the Topography and Geology of the Fayûm Province of Egypt, published by the Egyptian Geological Survey in 1905, I briefly referred in passing to some “curious blocks of sandstone, pierced by numerous borings”, described by the author, and I added, “they appear to be the exact replica of specimens brought home from Lake Tanganyika by Mr. J. E. S. Moore” (p. 519).

The Keuper rocks of East Nottinghamshire occupy almost the whole of that part of the county, striking slightly E. of N. and W. of S., and dipping at a very low angle in an easterly direction.

British geologists must have read Professor Coleman's Address to the Geological Section of the British Association with great pleasure and interest. As Professor Coleman remarks, geology finds some of its most seductive problems in the neglected extremes of the earth's history. Out of the apparent tangle of the ‘drifts’ and Archæan Gneisses Canadian geologists are now evolving an orderly sequence which must exercise considerable influence upon the progress of geology in other lands. The seemingly unnatural conjunction of Pleistocene and Archæan, Professor Coleman states, has furnished the clue to certain puzzling problems of the Archæan.

The wolfram veins in the Grainsgill greisen, near Carrock Fell, are an example of ore-bearing pegmatites, a vein-type uncommon in the British Isles, and one, moreover, the study of which is of much interest in its relation to ore-genesis. The veins have long been known, and intermittently exploited for tungsten-ore, but their economic prospects are not bright. Of previous workers, Mr. Alfred Harker has described the greisen which carries the veins, while the various mineral occurrences have been recorded by Mr. J. G. Goodchild and others.

The city of Nottingham is built upon the outerop of the Trias. Building and road-making operations consequent upon its rapid growth often lead to the laying bare of the underlying Bunter, Keuper Waterstones and Marls. Unfortunately the wort is usually carried on with such rapidity that good exposures are often missed. A temporary cessation of activities in one part of the Sherwood suburb, however, left a beautiful exposure of the Waterstones. A careful examination of this during the past few months has led to the discovery of footprints and fish-remains. The footprints are of a type which does not seem to fit into the generally used system of classification. In 1857 the Rev. A. Irving found a Cheirotheroid print in the railway cutting at Colwick. This is the only record of the previous discovery of footprints in this district.

Amongst the corals collected by the Geological Survey during the past season, and submitted to me for determination, two specimens call for special remark, since they appear at first sight to occur out of their true zonal position. They were found by Mr. Dixon on the Pembrokeshire coast, to the south and south-west of Castle Martin. In each case Mr. Dixon gives the horizon as C2–S1, in the terms of Dr. Vaughan's classification. They are, accordingly, of Lower Visean age.

The losses of their constituents during the decompositions of the rocks.— As shown in this paper the analyses of the rocks and of their decomposition-products do not indicate the extent of the degradation which has taken place. To ascertain this it is necessary to re-calculate the analytical figures so that their proportions are comparable to those of one of the constituents which is assumed to have remained unchanged. The structures of the Surinam and the British Gruiana bauxitic laterite show clearly that, contrary to what is not unfrequently assumed, alumina cannot be regarded as a static component in rocks and their decomposition-products. It is evidently under condition of lateritization capable of entering into solution, transference from place to place, and redeposition in the form of alumina hydrate where conditions are favourable. The constituent which appears to be the most stable under conditions of weathering is titanium oxide, especially that present as ilmenite. But unfortunately as a rule it is present in such low proportions in rocks and in their residuary products that, when taken as the static constituent, errors in analysis of low value are productive of variations of wide extent in the results calculated on them.