An interesting discovery having just been made in consequence of the examination of a single thin slice of rock, the following communication is recommended to the attention of those geologists who, to say the least, still fail to recognize the value of the microscope in geological investigations.

BY those accustomed to the hopeless confusion of the Greywacké of the earlier geologists, the publication of Murchison's grand work on the “Silurian System” was hailed with feelings of the most profound relief and satisfaction. His clear and brilliant presentation of the physical and palæontological proofs of an orderly sequence among the Palæozoic Rocks below the Old Red Sandstone, as originally set forth in all their force and harmony in his magnificent volumes, naturally astonished and dazzled the majority of his scientific contemporaries, and secured for his nomenclature of these ancient deposits an almost universal acceptance. His subsequent abuse of this advantage to strengthen and consolidate his own system at the expense of that of his equally - illustrious co-worker—the less fortunate but more cautious Sedgwick —was a gallant but unscrupulous defence of this original nomenclature, which by that time he must have felt himself almost powerless to disturb. His later extension downward of the limits of his system, till it embraced all the rocks between the supposed Azoics and the Old Red Sandstone—though, in a measure, forced upon him from without—ought perhaps to be regarded in part as a very natural return to the ideas of his early teachers, who had always held the practical unitly of the rocks of the Transitionalperiod. In this wey, however, Murchison unwittingly destroyed many of the most beneficial results of his won labours; in a sense, spending his old age in the attempted re-erection of the very edifice it hed been the pride of his manhood to destroy—the early years of his scientific career being devoted to the worthy task of proving the marvellous variety of the Lower Palæozoics; his later years to demonstrating their integrity, unity, and indivisibility.

To the recently published paper by my father, “Palæontology of the Coasts of the Arctic Lands visited by the late British Expedition,” etc., I contributed some notes on the Polyzoa obtained during the progress of the Expedition from the Palæozoic rocks of the regions visited. Amongst other forms I referred at some length to Dr. F. Toula's genus Ramipora, and pointed out its affinities to various genera of Palæ Polyzoa, and more particularly to Synocladia, King, in the following words:—“ It appears to differ from the first of these” (i.e. from Synocladia) “in the absence of dichotomization of the stem and primary branches, so far as the remains of it are known to us; secondly, in the bilateral symmetry of the latter; thirdly, in the fact that the cells all open on the same plane on each side the median keel, whereas in Synocladia the stems and branches are divided longitudinally by several carinæ, between which the cell apertures occur. Again in Ramipora both aspects of the polyzoarium are carinate, but in Synocladia only one. Lastly, in Synocladia the dissepiments all appear to be regularly celluliferous, but in Ramipora this does not appear to hold good to the same extent.”

An interesting discovery has just been made in this district. A short time since some workmen from Cumnor brought to the Museum a basketful of bones which they said they had found in digging the clay at the brick works, now in course of large extension, at Cumnor Hurst, three miles west of Oxford. On cleaning the specimens, the characteristic vertebræ and teeth of Iguanodon were recognized. A large number of the vertebræ are entire, but the jaw is in fragments, with many teeth, however, in position. The skull is wanting, except a small fragment. One of the feet, with the claws, is almost complete. The larger bones are almost all broken, buty we hope to be able to reunite many of the fragments, as there is reason to belive that the skeleton was entire or nearly so. The smaller bones and the extremities of the larger bones are in a beautiful state of preservation. It is a smaller animal than the Wealden Iguanodon Mantelli, but whether owing to age or difference of species remains to be determined. It seems to be indicate a different species, with smaller and more delicately-formed bones.

We possess only a few elements of the Insects of the Coal Period—Articulata are rare in these beds, and it is only after long research that we are able to collect sufficient materials for a special work on the Entomology of this epoch.

The results obtained of late years, through the numerous investigations which have been carried on amongst the Pre-Cambrian rocks in Great Britain, combined with the important discoveries of many additional areas to those previously known, seem to require that some general attempt should now be made to correlate the principal groups where they have been observed; and to classify them according to the prevailing types of rocks recognized therein, and peculiarities observable.

Four years ago M. R. D. M. Verbeek, Director of the Geological Survey of the West Coast, Sumatra, placed in the hands of my friend Prof. T. Rupert Jones, F.R.S., for description, a collection of fossil remains obtained by him in the prosecution of his geological researches in Central Sumatra, accompanied by some notes and sections of the geology of this little-known region of the globe.

1. History.—The genus Cladochonus was founded by Prof. M'Coy in 1847 (Annals Nat. Hist. vol. xx. p. 227) for certain Australian Palæozoic corals with “some relation to Aulopora,” but differing “in their curious erect habit, regular, angular mode of branching, slender, equal stem-like tubes, and abruptly dilated terminal cups bent in nearly opposite directions.”Prof. M'Coy also lays stress upon the thickness of the walls in Cladochonus, and the proportionately small calices, and states (loc. cit., and Ibid. 1849, vol. iii. p. 134) that the curious little corals formerly referred by him to Lamouroux's Jania will fall into this genus, viz. Jania crassa, and Jania bacillaria (Synop. Carb. Limestone Foss. Ireland, 1844, p.197). The Australian species Cladochonus tenuicollis is distinguished by the slenderness of the stolons connecting the calices. In 1851 Messrs. Milne-Edwards and Haime described a genus under the name of Pyrgia (Polyp. Foss. Terr. Pal. p. 310). which has been placed by subsequent writers as a synonym of Cladochnons, and we think with good reason. To their genus they assign the following characters—the corallum is free, pedicellate, with a strong epitheca, very deep calices, and without traces of septal striæ, and they consider that it differs from Aulopora in its simple and free habit. Two species were described, Pyrgia Michelini, Ed. and H., and P. Labechei, Ed. and H. The Janiæ of M'Coy they reserve their opinion on, but C. tenuicollis of the same authour is referred by them to the young of the genus Syringopora (loc. cit. p. 296). Similar views were expressed by them in their subsequent “Monograph of the British Fossil Corals” (pt. 3, Corals from the Perm. Form. and Mounatain Limset. p. 164). 1 and they further describe their Pygria Labechei (loc. cit. p. 166).

The following notes upon the Kuriles were collected during an excursion which I made to these islands in the summer of 1878. Owing to a continuance of foggy weather, which I do not think would find its equal even in Newfoundland, the want of harbours, and the strong currents, although I was almost a month steaming. amongst these islands, it was seldom that we could effect a landing. In consequence of this the bulk of the material embodied in the following notes was written from what I saw from the deck of our vessel. However, as I had good opportunities for seeing nearly every island in the group, and many of these from several points of view, the following notes may not be altogether without value. One advantage which was gained by viewing these island from a distance was, that I was thereby better able to judge of the number, and the general from of the mountains they contained, and to roughly make comparisons of their relative heights, than I could have done had I been actually on the island themselves.

Last summer I paid a visit to the Parallel Roads of Glen Roy, and saw certain features which must, I think, have hitherto escaped notice. It has been asserted that the roads consist of, or are cut out of, mere superficial detritus; and that they never appear where the solid rock appears; and much discussion has arisen as to the mode of formation of the roads on this supposition, viz. that they consist of detritus merely.

Introduction.—In previous papers upon the Geology of the English Lake District, which I have had the honour of laying before the Geological Society, special considerations of theoretic significance have been dwelt upon, and in the official memoir upon the Geology of the northern part of the English Lake District, detailed facts have been brought forward and a sketch given (in chap. xii.) of the original relation of the formations to each other, and their physical history. I yet venture to think, however, that there is need of a general summary of the facts relating to Physical Hiatory which may reach a wider circle of readers than do the offical memoirs, and which may stimulate further inquiries into this deeply-interesting subject. The following pages may therefore be regarded as a sequel to my former papers on the district, and in some measure as a last chapter to the story told thus far.

A not uncommon fossil of the Chalk, in both the upper and lower divisions, is an elongated, and more or less undulating body, composed of the scales and bones of fishes confusedly mingled one with another, and known to the quarrymen as “Petrified Eels.” Dr. Mantell was the first to discover and describe these singular objects; he says, “A long cylindrical fish, of which neither the fins nor the extremities have been discovered, is one of the most frequent, but most imperfect of the Sussex ichthyolites. The specimens are of a subcylindrical form, rather flattened by compression, from six inches to two feet in length, and about one inch wide. They occur abundantly in the Upper Chalk, and occasionally in the siliceous nodules. They are, for the most part, perfectly straight; but some specimens are undulated, as if the fish had been suddenly enveloped in the Chalk while in a state of motion. The surface is covered with small delicate smooth scales, confusedly mixed together; not one instance having been noticed in which they are disposed with any degree of regularity.”

Through the kindness of the late Rev. W. B. Clarke, of Sydney, I had the opportunity of examining two collections of fossil plants from Australia, which that gentleman had kindly placed at my disposal, together with explanatory notes, which he communicated to me in private letters.

On this part of the Yorkshire coast, the storms of last winter have often bared parts of the beach, for a time, of their usual covering of sand and shingle, and have thus exposed to observation many interesting features in connexion with the Drift series. Of these, the most instructive point which has come under my notice is the one which forms the immediate subject of the present communication.

In the GeologicalMagazine for December, 1876, appeared a short paper on certain clay beds near the south-eastern shores of Lough Neagh. The paper is intended to supplement a more extended communication entitled, “On the Age and Mode of Formation of Lough Neagh,” read by the same author—Edward T. Hardman, Esq., F.C.S., H. M. Geol. Survey of Ireland— before the British Association in 1874, and also read before the Royal Geological Society of Irealand in January, 1875. The beds in question are described“as a very extensive and important deposit spreading (under water and on shore) over an area that cannot be less than 180 square miles in extent, and probably in some places 500 feet thick. They repose on the basalt, and are covered by drift. All the evidence we have points to their being of Pliocence age.” The author, after giving a sketch of the Geology and physical Geography of the district, proceeds with a description of the clay beds and associated lignites, and gives abstracts of numerous borings ranging in depth from a few feet to 192 feet, which have been made over this area. These borings disclosed a series of light-grey and variously-coloured plastic clays, containing hard nodules of clay-ironstone inclosing leaf and other plant-remains, also large quantities of black lignite, occurring frequently in masses throughout the beds, but sometimes bedded.

The Whetstones (Meule) of Bracquegnies, Belgium, are upon the same geological horizon (zone of Ammonites inflatus, Sow.) and are identical lithologically with the well-known Whetstones of Blackdown; like to the latter deposits they are characterized by the prevalence of Trigoniæ which are allied to, but are for the most part not strictly identical with the species of Devonshire.

Certain zones of the massive grey dolomite belonging to the Niagara Formation in North America are so largely composed of fossil corals as to indicate similar conditions of formation to that of the coral reefs of the present age. Perhaps no better examples of these Palæozoic coral reefs could be found than those which are exposed in many tracts of the surface of the Great Manitoulin Island, which are literally covered with complete and fragmentary corals in a silicified condition, which have been weathered out of the matrix of hard dolomite in which they had been imbedded. The great majority of these corals belong to the well-known genera Favosites, Halysites, Heliolites, Alveolites, Cænites, Syringopora, Strombodes, Cyathophyllum, Zaphrentisand Omphyma, and many of the species are also common to the Silurian rocks of Europe. A recent search in the dèbris of one of these ancient reefs has brought to light a coral which appears to belong to a new genus, with the following characters.

The materials for a classification of the later Pleistocene deposits of Cornwall are so voluminous that it was found impossible to embody them in a single paper. Having submitted to the Geological Society a general classification with such notices of the deposits as seemed necessary to show the grounds whereon it was based, I purpose in the following paper to complete the notices of deposits. As an apology for the amount of compilation thus rendered necessary, I must plead the object of the papers, viz. to place in one view all that has been written on the subject, as references alone would entail more time and trouble in looking up than many readers would be disposed to concede.

The general structure and mode of growth of coral reefs and islands is well understood; but there is one attendant circumstance of considerable geological interest, to which, so far as I am aware, attention has never been called. This is the peculiar stratigraphic relation of the different strata in the reef to their chronological equivalents in the deposits of the surrounding ocean; a relation due to the comparatively rapid growth of the reef as a whole.

In the spring of the year 1878 I brought under the notice of the Geological Society a paper describing for the first time as Marine, the Upper Series of the Bournemouth strata, present in thickness to the east of Bournemouth Pier. The publication has been delayed, but the present sketch will only to a very slight extent forestall it, and is written simply with a view to make clear the synchrony of the Bournemouth Marine Beds with the lower part of the Bracklesham Beds of the Hampshire Basin, the Middle and so-called Upper Bagshot Beds of the London Basin, and the Bovey Tracey Beds, the true position of the latter, especially, being more clear at the present moment than it was a few months ago. I propose first to describe briefly the Bournemouth Marine Strata, and then the other formations with which I have correlated them, in the order in which they are mentioned above.