One of the most important additions recently made to the Gallery of Fossil Reptilia at the Natural History Museum, is a mounted skeleton of the highly specialized Ichthyosaur known as Ophthalmosaurus icenicus, Seeley. This reptile presents many. peculiarities, for the most part indicating a very high degree of adaptation for life in the open sea and for rapid movement through the water, probably sometimes at considerable depths. In fact, Ophthalmosaurus may be regarded as representing among the Reptilia the swiftly swimming toothed-whales among the Mammalia, and it is interesting to note that the similar mode of life in the two cases has produced in some respects similar modifications. Thus the front paddles are enlarged, the hind ones reduced; in whales the latter have disappeared altogether. Again, there was a large caudal fin, vertical in this case, and the head was elongated, the snout sharp, and the neck so short as to be practically non-existent. The enlargement of the fore-paddles is brought about by the presence of a very large pisiform bone, which together with the radius and ulna articulates with the humerus, thus forming a very broad base for the expanded terminal portion of the paddle. Another striking peculiarity is the great reduction of the dentition, the teeth in the adult being very small and confined to the front of the jaws. Baptanodon, an American form very closely allied to, if not identical with, Ophthalmosaurus, was for a long time regarded as toothless. This reduced dentition, so unlike what is usually found in members of the group, must indicate some considerable change in the nature of the food, but what this was is unknown.

During the years 1906 to 1909 a bore was sunk at Seascale on the coast of Cumberland, 9 miles south-eastward from St. Bees, in the hope of reaching a continuation of the Coal-measures which, south of Whitehaven, end against the Trias. This bore reached the depth of 3,200 feet, and it was then still in the Red Sandstone Series, which it entered beneath 20 feet of drift. Owing to the kindness of Mr. Forster Brown, I received a copy of the bore section, and from Mr. Fleming Smith, of Cleator Moor, manager of Vivian's Boring and Exploration Company, Ltd., who carried out the boring, further information regarding the bore, two samples of the core, and a copy of the journal for the lowest 180 feet. As the bore record is of especial geological interest, I am indebted to Mr. Forster Brown for permission to publish it.

Although numerous papers, principally by the late E. Wilson, describing the beds of the Rhætic and the Lower Lias of Notts, were published while exposures existed along railway cuttings in the south-east of the county, no account of the precise positions of important fossils is to be found. These exposures are now all grass-grown, but the junction of Rhætic and Lias may be seen in a number of quarries where hydraulic limestone is worked, either for cement or for road material. One of the best is at Owthorpe. Those at Cotgrave Gorse, Barnstone, Plumtree Wolds, and Normanton Hills are confirmatory. The layers rich in Foraminifera have been of value in correlating these sections.

The intrusive rocks of Marston Jabet and Chilvers Coton, though probably of quite minor importance, have been rendered noteworthy by the variety of opinions held regarding their true position in a scheme of rock classification. This is especially the case as regards the rock quarried at Marston Jabet. Thus Allport comments upon certain remarkable features distinguishing this rock, which, however, seems to be covered by his general statement that the intrusive rocks of the Warwickshire Coalfield are for the most part ordinary diorites. Rutley concurs in the opinion expressed by Allport. Watts calls attention to the lamprophyric aspect of the rock, which he terms a camptonite; and with this description Harker agrees. Hatch admits the lamprophyric features and incidentally refers to the lack of recorded analyses.

Although the calcium oxide and magnesia of sedimentary limestone and dolomite must all be derived from pre-existing igneous rocks, it is not so easy to trace the origin of the necessary carbon dioxide. The solidified igneous rocks contain mere traces of free carbon dioxide and of calcite. During their weathering carbon dioxide is taken up from the atmosphere, replacing the silica of calcium silicate and magnesium silicate minerals, and forming the carbonates. Now, however, the quantity of carbon dioxide retained in the atmosphere is exceedingly small. It is difficult to credit, for instance that a layer of coal, 1½ millimetres thick, covering the surface of the globe, on being burnt would yield as much carbon dioxide as the entire atmosphere now contains. A similar layer of limestone containing an equivalent amount of carbon dioxide would have a thickness of 5 millimetres. This is out of all proportion compared with the mighty beds of limestone and dolomite now forming part of the earth's crust. Nor would the carbon dioxide of the sea avail anything. It exceeds in quantity that of the air, but is still at the most equivalent to 7 centimetres of limestone covering the earth's surface. Now the existence of animal life throughout the sedimentary era implies that from the earliest times, the composition of the earth's atmosphere cannot have differed very materially from the present one.

In Professor Shand's reply to my criticism of his original paper on the application of the principle of saturation with respect to silica in the classification of igneous rocks, some points arise which make it clear that he has misunderstood me in several particulars. In the beginning of my paper, it was explicitly stated that what was to be considered was (1) whether the principle, as enunciated by Professor Shand, could be extended to minerals other than the silica ones (quartz, tridymite, etc.), the felspars and the felspathoids, and (2) whether the criterion whereby the rock minerals were divided into the two groups of saturated and unsaturated was sufficiently exact. The criterion used was that of “the observed facts of distribution”, and any mineral which was found coexisting with quartz or some other form of silica in igneous rocks was said to be saturated, while those which did not occur along with quartz were said to be unsaturated. Correspondingly, rocks which consisted entirely of minerals of the former type were classed as saturated, those consisting of mixtures of the two types as part-saturated, and those consisting solely of the second type as unsaturated. I endeavoured to show that the rock-forming minerals cannot be satisfactorily divided into two classes in this empirical fashion, without any consideration of the cooling-histories of the individual rocks in which the minerals may be found.

The notes by Professor Grenville A. J. Cole & Mr. T. Hallissy on the Wexford Gravels, and those by Dr. F. Cowper Reed on the Manxland shells in the Strickland Collection at the Sedgwick Museum, Cambridge, published in last year's Geological Magazine, will be welcomed by geologists as drawing attention to an interesting but too long neglected subject. The principal object of this paper is to point out the faunal relations of the deposits in question to each other, and wherein they differ from those of the neighbourhood which are usually grouped with them, including the high-level shelly drifts of Moel Tryfaen, Macclesfield, Gloppa, and the Wicklow Mountains, the limestone drifts and shelly clays of Ireland from Ballybrack Bay to Glenarm, and the stony or boulder clays of Cheshire and Lancashire.

Fossil remains in the Coniston Grit Series in the Lake District are generally so scarce, except in the flaggy beds exposed in the quarry near Latrigg on Applethwaite Common, that considerable interest attaches to the discovery, made in January of the present year, of a bed which is highly fossiliferous, in a quarry recently opened in connexion with the drainage works of Bowness and indermere. The quarry is close to the shore of the lake, near the outh-west corner of the Calgarth estate.