In a paper read by me before the Geological Society of London on November 26th, 1890, I mentioned that I had obtained evidence during a recent visit to North Devon which had led me to believe that far too little importance had hitherto been assigned to the results of movements in the earth's crust as affecting the succession of the rocks in that area. I mentioned also that the supposed continuous upward succession from the rocks on the shore of the Bristol Channel to those in the neighbourhood of Barnstaple, including, according to some authors, no less than ten distinct groups, was an erroneous interpretation; for the beds are greatly plicated and faulted and several times repeated. Therefore instead of being one continuous series with a regular dip to the south, the beds are much folded in several broken troughs.inthis paper I purpose giving some examples of the folds and faults near Ilfracombe which will enable those who visit that neighbourhood to verify the statements which I have made in regard to some of the rocks in that area.

The summer visitor to Lyme-Regis, to Scarborough, or to Whitby, is familiar with the little Ammonites, mounted in silver as brooches for ladies, and may even have seen them also with heads carved, to represent coiled-up serpents, with gieen or pink eyes of glass, inserted by the enterprising jeweller.

In a paper read before the Geological Society of London, in 1889, I contended that the biotite of the gneisses and schists of Malvern had been produced out of hornblende through the intermediate form of chlorite. As this mineral change is of capital importance in explaining the origin of the Malvern schists, I made it one of the principal topics of the paper, and I trusted that the evidence I offered in support of it would be considered adequate. The further communication on the Malvern rocks, which I read on April 26th of the present year, assumed the adequacy of this proof. I found, however, that in certain quarters some scepticism on the point still existed, and it was suggested that I had overlooked some of the chemical difficulties which seemed to forbid the acceptance of my view. I therefore crave permission to reply to this objection in these pages ; and I desire, at the same time, to point out that since the reading of my paper in 1889, the production of biotite from chlorite has been affirmed by several writers of admitted authority.

The only important fragment of a Pycnodont fish hitherto known from the English Cretaceous Formations, is the portion of head and trunk figured and briefly noticed by Dixon under the name of Gyrodus angustus, Ag. This specimen displays the splenial bones from the oral aspect; some of the vertebral hæmapophyses; and thick scales with a reticulated ornament, covering only the anterior half of the trunk. The ventral ridge-scales also exhibit very conspicuous serrations. The splenial bones are imperfect, but sufficient to show all the essential characters of their oral face; and these elements present the only unique feature in the specimen. It will be observed that, whereas in all Pycnodont splenials hitherto described the dentition reaches the outer border at least in part of its extent, the bone in Gyrodus angustus has a wide toothless outer margin and an attenuated knife-like edge. The two vacuities in this margin shown in Dixon's figure are partly due to accident, partly imaginary, and there is no doubt that the bone forms a continuous whole.

Under the true Carboniferous strata of Ohio, that is below the base of the Berea Grit, lies a mass of shale of varying colour many hundred feet in thickness. The uppermost fifty or sixty feet are often red or reddish, and have been separated with the name of the Bedford Shale. The next layer, of about the same thickness, is usually black or at least very dark and bears the name of the Cleveland Shale. Below this again is a greenish mass 500 feet or more in thickness, known as the Erie Shale. Another dark bed follows—the Huron Shale—beneath which is the great limestone base of the Devonian in Ohio, the Corniferous.

For many years the writer has wished for the means to bring about some uniform system of glacier observation, and more especially the collection of data respecting ice-movements in British Colonies, and territories under British influence. When we think of our mountains in the Dominion of Canada and in New Zealand, and the vast ranges of the Himalayas (these last we shall before long hear about from Mr. Conway), it seems a great pity that such promising fields should not be adequately worked. In an article in the Alpine Journal, for February, 1891, the writer sketched a plan of operation; and in the same Journal, for February, 1893, asked for a committee to communicate with such Colonial Governments as could take part.

A thick mass of bedded schists, as I have described in more than one paper, occupies the highest position among the socalled metamorphic rocks of the Alps. With the exception of some gneisses—so far as I know of a porphyritic character, and almost certainly intrusive granites modified by pressure— and various green schists, which, in part at least, are basic igneous rocks, similarly affected, the group, which may be traced from one end of the chain to the other, consists of altered sediments.

It is one of the most fascinating of the recreations of a geologist to attempt to reconstruct the physical features of some past period; and though our essays in this direction have not been attended with complete success, and our maps of early epochs bear a striking resemblance to those of Herodotus and Ptolemy, yet thesemaps have their value and they are at least steps towards one of the goals of the science of geology.

The question of the submergence of the British Isles during, at least, one stage of the Glacial period, is deserving of careful consideration by geologists. Until the visit of the late lamented Prof. Carvill Lewis to this country, no one, as far as I am aware, questioned the view that the British Isles have been submerged to a depth, in some places, amounting to 1300 or 1400 feet—this being the level at which shell-beds are found in some parts of England, Wales, Ireland.

A series of specimens showing successive stages in the development of a remarkable malformation of this species seems to me quite worth recording. The specimens are all from the Carboniferous Limestone of Settle.

In a recent article on the Pre-Cambrian Rocks of the British Isles in the Journal of Geology, vol. i., No. 1, Sir Archibald Geikie makes the following statement: “There cannot, I think, be now any doubt that small tracts of gneiss, quite comparable in lithological character to portions of the Lewisian rocks of the North-West of Scotland, rise to the surface in a few places in England and Wales. In the heart of Anglesey, for example, a tract of such rocks presents some striking external or scenic resemblance to the characteristic types of ground where the oldest gneiss forms the surface in Scotland and the West of Ireland.” To those who have followed the controversy which has been going on for nearly thirty years between the chiefs of the British Geological Survey and some geologists who have been working amongst the rocks in Wales, the importance of the above admission will be readily apparent; but as it is possible that some may be unable to realize what such an admission means in showing geological progress in unravelling the history of the older rocks in Wales during the past thirty years, a brief summary of the results obtained may possibly be considered useful.

There are some points of special interest with reference to the Insect remains from the Bembridge Limestone, near Cowes, which seem to be worth recording. My friend Mr. Scudder, who has done so much to promote the study and elucidate the history of fossil insects, and who is our highest authority upon the subject, remarks in one of his papers in the United States Bulletin, that in no case had he observed the interior of any insect in a fossil state, and that the internal structure could hardly be expected to be detected.

The extraordinary abundance and almost universal distribution of fragments of Eskdale granite through the Drift of the North-West of England and part of North Wales is an impressive fact to the student of Glacial Geology. Mackintosh was the first to systematically trace this rock through the Drift and to note its origin. Since the time of this single-minded and patient investigator many other geologists have gone over the same ground and extended his observations, and all must bear witness to the accuracy of his facts.

In 1887 and 1888, Sir J. W. Dawson discoveredindark carbonaceous shales of the Quebec group, exposed at Little Métis, on the north shore of the Lower St. Lawrence, some thin bands of rock largely filled with the remains of siliceous sponges, and similar fossils were found to be sparsely scattered in adjacent beds through a vertical thickness of forty feet. This discovery of an abundant sponge fauna at so low an horizon,inrocks previously considered

The rocks of Raasay have attracted a good deal of attention from geologists, despite the fact that no house of public entertainment exists on the island. That portion of it which lies to the south of Brochel Castle, exhibits a base of Torridon Sandstone, above which there may be traced, more or less completely, in two faulted areas, an ascending series from the New Red rocks to the Great Oolite group. The Jurassic strata are finely exhibited in the eastern cliffs, but westwards they are largely covered by volcanic rocks, and especially by great sheets of Granophyre which descend in that direction to the sea-level. To the south-west there is a mass of Gabbro; in other parts there are sills and countless dykes of Basalt, while the summit of Dun Caan is formed of a bedded mass of that material. Coverings of Peat, of Boulder-Clay and Gravel, serve to add variety to the geology, and to obscure the outcrops of the Jurassic and other rocks.

The late Admiral Spratt, R.N., and Dr. John Murray, of the “Challenger” Expedition, have, in their brochures on Maltese Geology, made allusion en passant to the occurrence of chert nodules in the Globigerina limestones of the Maltese islands. Neither of these gentlemen, however, gave any details of the nature, mode of occurrence, or distribution of the concretions, an omission which was probably due to the restricted area of the horizon at which the nodules are found, and to the irregular and sparse manner in which thev are distributed.

The specimen which forms the subject of the present communication was obtained by one of the writers from the Carboniferous Limestone, near Dublin. Although one side of the specimen is covered by matrix, yet the other side and the periphery are so splendidly preserved, and the shell has not been distorted during fossilisation, that the characters of the fossil can be accurately determined (see Woodcut, p. 254).

Since writing my previous paper on the question of whether, during the so-called Glacial period, the Arctic lands had a milder and not a more severe climate, I have met with some evidence on the subject so important and suggestive that I feel sure it will be welcome to some of your readers, especially as it involves a considerable departure from conventional views. In 1861 Sir Joseph Hooker wrote his famous paper on the distribution of Arctic plants, in which he argued that the flora of Greenland is distinctly of European type; that Greenland is a sub-region, in fact, of the Scandinavian Botanical province. To state his own conclusion in his own words, “the flora of Greenland is almost exclusively Lapponian, having an extremely light admixture of American or Asiatic types.”

In previous communications, to the GEOLOGICAL MAGAZINE I have subjected the evidence as to the age of the Mammoth in the British Islands to criticism, and I ventured to conclude that whereever we can find the remains of the Mammoth and its contemporaries undisturbed and in situ, these remains are found under and not over or in the drift. This, so far as I know, is the case in every recorded instance where the Mammoth beds and the drift have been found superimposed upon each other. Let us now turn to the Continent and test the problem there. If we are to test it in the same way, which I take to be the only satisfactory way, namely, by evidence of superposition, we must naturally limit our survey to countries where the drift actually occurs. First, let us turn to Switzerland.

About one quarter of the Island of Jersey is occupied by argillites or fine grits, often of a greenish grey colour referred by French geologists to the “Phyllades de St. Lo.” They are, therefore, if not equivalent to the Lower Cambrian beds of Britain, slightly more ancient.inclose association with these, but according to Prof, de Lapparent, belonging rather to the upper part of the group, occur certain more or less porphyritic rocks, as to the origin of which different opinions have been entertained. M. Nouryinhis useful “Geologie de Jersey ” describes them under the name of “spilites.” While admitting that in many respects they exhibit the characters of an eruptive rock, he concludes, after an elaborate discussion, that they are metamorphosed argillite, the change being primarily due to the “poiphyres pétrosiliceux;” the felspar crystals, however, he thinks, may be attributed to the action of the diorite.