It is hardly necessary to point out how very important it is that those on whom falls the onus of naming a rock should decide which is the most fitting name only after very careful consideration. Some there are who profess to be above the petty worries of nomenclature, and from these only a loose application of rock names can be expected. This is liable to mislead those dealing with problems of petrogenesis, who are justified in assuming that those competent to carry out geological research are also competent to apply correct names to their discoveries. That this is often not the case can be easily demonstrated from quite recent papers. The difficulty arises from two causes: the lack of a system of rock classification which in any sense approaches the ideal, and a desire for brevity. Concerning the first difficulty it is sufficient to say that little advance in placing the nomenclature of rocks upon a firm and common basis is possible until one universally recognized system of rock classification is in use. It is still open for investigators to choose, without any set standard, which of several variable characters of a rock should be the criterion upon which the systematic position of the rock depends. Thus, one writer places mode of occurrence before micro-structure, while his neighbour deems it wise completely to ignore mode of occurrence and makes micro-structure the deciding factor.

A new species of Palaeechinus, and the first certain member of that genus from North America, is described and several unusual features of its test noted. The apical disc of the specimen is extremely well preserved.

In the year 1886 the late Dr. G. M. Dawson gave an account of a syenitic rock, rich in a beautiful blue sodalite, which he had discovered when exploring the district near Hector Pass, on the watershed of the Canadian Rocky Mountains, and an analysis of the mineral was afterwards published by Professor Harrington. The place was visited last Summer by Mr. E. Whymper during his examination of the district south of the Canada Pacific Railway, when he collected a number of specimens, which he showed to me on his return. The rock is hardly less beautiful than lapis lazuli, and as no description of its microscopic structure has been published, as far as I can ascertain, I give the results of my examination, together with a condensed account of its mode of occurrence. I am much indebted to Mr. Whymper for placing his specimens at my disposal, to Mr. L. Fletcher, Keeper of the Mineral Collection in the British Museum, for the opportunity of examining specimens of sodalite rock not in my own cabinet, and to Mr. L. J. Spencer, of that department, for giving me his kind assistance and valuable references to papers about the mineral.

The melting intervals of basaltic magmas are investigated in detail at various pressures, as the size of the interval has an important bearing on the genesis of igneous rocks. Tholeiitic magmas do not have a more pronounced four phase proximity at low pressures than at higher ones. This result seems to oppose the generally accepted low pressure character of these magmas; but as there is a general decrease in melting intervals with increasing pressure, the four phase proximity is nevertheless sustained. The melting intervals of alkaline rocks decrease rapidly with increasing pressure. Small variations in the temperature may therefore generate large variations in the composition of the liquids developed at high pressures.

The bones of the carapace and plastron from which this species has been determined were discovered in a thin seam of grey sand intercalated in the Mammalian band of the Lower Headon Beds at Hordwell, Hampshire. They were lying scattered over an area of about four feet. The broken edge of the entoplastral and right hyoplastral were sticking out of the cliff face. The sea had carried away the missing portions of these bones and probably those lost of the carapace and plastron.

Every geologist is familiar with the name of Storeton Quarry, which may fitly be termed the “home of the Cheirotherium”, celebrated as being the scene of the earliest discoveryinEngland of the fossil footprints, first described by Messrs. John Cunningham and James Yatesin1839.

Fifty years' study of these footprints has left their origin, so faras exact identification with any known animal is concerned, a matter of as much mystery as when Sir Eichard Owen gave attention to the subject in his classical work on “Palaeontology”.

The Upper Carboniferous rocks of the Ingleton Coal-field in North-West Yorkshire present a difficult study, and at the present time they are very imperfectly known. As mapped by the Geological Survey, there is apparently a perfect succession, passing up from the Yoredales, through the Millstone Grits, to the Lower and Middle Coal-measures. The coal-measures are in part overlain hy a series of red rocks, which have been assigned to the Permian, as in the case of other of the Midland Coal-fields. In the index of the Survey map of the north-eastern portion of the coal-field, the Deep Coal is taken as the top of the Lower, and the bottom of the Middle Coal-measures.

A technique is described for direct analysis of rock-fabric, utilising hardness differences between various mineral constituents. This renders unnecessary the intermediate step of measuring optical orientations. The direct relation that exists between hardness of the components making up a particular fabric and the start of plastic deformation of each mineral can be measured quantitatively on the basis of polishing hardness differences. If the surface roughness signal is digitalised, then it is possible to automatically construct a microtopography, with contours delineating resistance of individual minerals.

In the last two British Association Reports of the Vesuvian Committee, I drew attention to some very large masses of trachyte traversed, at the back of Naples, by the tunnel of the Cumana Railway. A full account of the stratigraphy of these will be deferred until some further excavations, now in progress, are completed. I propose at present merely to describe the earliest-discovered and most striking of these masses.

Many of the rocks of this district have been already described by the late Mr. E. B. Tawney, in a series of papers entitled “Woodwardian Laboratory Notes,” contributed to the Geological Magazine a few years ago. The following additional remarks are to a certain extent supplemental to the above-mentioned papers, and are founded on a microscopical examination of a large series of rocks, collected some few years ago during a brief visit to the Lleyn district.

In the discussion on a paper read recently by A, G. MacGregor on Scottish Carboniferous volcanicity,1 one of us, speaking on behalf of both, raised some points concerning the nomenclature of magma-types which we feel are worth amplifying. The points at issue concern firstly the use of the terms “tholeiite” and “olivinebasalt” when applied to fundamental magmas, and secondly the propriety of referring to the suites of rock-types supposed to be derived from them as “calc-alkali” and “alkali” respectively.

Large-scale extractions from a limestone quarry immediately east of the village of South Cornelly have provided sections of the Dibunophyllum Zone (probably the top of D1 Subzone) showing deep piping at two separate horizons. On the lower sides and floors of some of the larger pipes, the limestones and pseudo-breccias have been metasomatically replaced by a thin layer or by irregular pockets of haematite up to a foot in thickness. All the evidence points to two periods of emergence and sub-aerial erosion followed by lagoonal conditions with a Keuper-like environment when the irregularities of the underlying rock surface were filled with marl.

The Fuller's Earth Clay of the Whatley district nowhere rests directly on the Palaeozoic rocks, but is always underlain by Inferior Oolite. The Fuller's Earth Rock of the district contains two distinctive and successive faunas, the upper of which bears a suite of ammonites hitherto unknown from rocks of this age. It is correlated with the Wattonensis Beds of the Dorset Fuller's Earth.

The extraordinary abundance of Bryozoa of the order Cheilostomata which occurs throughout the Cainozoic era,incomparison with their scarcity in earlier formations, has often been remarked. Interesting explanations of the suddenness of their appearance have, moreover, been offered by those who do not attach so much importance, as do some, to the imperfection of the geological record. Cheilostomata are not unknown from earlier deposits: the Cretaceous system has yielded a fair number, while even as early as the Silurian species have been found. Though doubts have been thrown on these early records, there seems no sufficient reason to discredit them. Even if Prof. Nicholson's Hippothoa inflata (Hall) should turn out to be a Stomntopora, which, if the figure be correct, is most unlikely, there remain many species in later Palæozoic deposits: such are those belonging to Prof. James Hall's genus Paleschara? which Mr. Ulrich accepts as Chilostomatons, though Prof, von Zittel includes it doubtfully with the Ptilodictyonidæ. Some of the specimens of Lichenalia, etc., figured by Hall, as well as the same author's Cystopora geniculata, may also belong to this order.

THE genus Dimorphograptus was founded by Lapworth (1876) for uni-biserial graptolites transitional between Diplograptus and Monograptus, evolution along what is now termed the “ Monograptid trend ” leading to the production of a uniserial proximal portion of the rhabdosome. Akidograptus has been proposed more recently by K. A. Davies for an early stage in the Dimorphograptus series, represented by the species Ak. acuminatus (Nicholson) and Ak. ascensus Davies.

During the last few years the Coal-measures have been reached through the overlying New Red Sandstone in three Collieries, and in three bore-holes, in that part of South Lancashire which lies between the St. Helens and Wigan Coal-fields and the River Mersey. The results were in some degree unforeseen, as the Trias was thinner than might have been expected, while it seems likely that the Permian formation is altogether absent.