The several species of Eryon, described by various authors, appear to be distinguishable as separate genera, which are as definable from one another as from the recent forms of Polycheles and Willemœsia; but the variability appears not to be greater than in those that are separated in time through geological æons, than in those that are contemporaneous in geographical space.

On no branch of geology has there been more imaginative writing than upon metamorphism. Some speculations have, indeed diverged into the humorous. Keen-eyed observers, with vision capable of piercing through miles of solid rock, have described to us those processes of subterranean cookery by which Pluto has converted sandstones and shales into granite, metamorphic schists and porphyries. If water was used, the rocks were “stewed”; if not they were only “baked” or perhaps “melted.” Furthermore, it was declared, and text-books submissively taught, that rocks of almost every epoch have sometimes undergone these mystic changes: In North America, some metamorphic schists were “Triassic” while in the European Alps we had granite and gneiss of “Eocene” age. In Britain, men were more moderate, and we were not asked to extend our faith beyond the limits of the Palæozoic formations. The evidence on which these conclusions were advanced was mainly of two kinds. A metamorphic rock associated with unaltered beds was proved to be of the same age as the latter, because either it overlay or passed into them. Thus, as an illustration of the former, the newer gneissic rocks of the Northern Highlands were said to be Ordovician, because they rested on Ordovician limestone and quartzite. Murchison saw the gneiss lying on the top of the limestone or the quartzite, and he said that the upper beds were the younger. Everybody believed him, except Nicol, who died discredited and disheartened. Now, we know that Nicol was right, and the great authority, misled by superficial appearances, was wrong.

A Little more than half a mile in a direct line south-east of the village of Great Crosby, at Moorside, the Silicate Brick and Tile Company are excavating clay and shale for brick-making. The excavation at present is about 60 yards square and 35 feet deep from the original surface of the ground to the lowest point. It discloses a section of much interest.

An examination of the fine series of the remains of Anthracotheriidæ from the Hempstead beds of the Isle of Wight contained in the British Museum, and their comparison with specimens and casts of the remains of the allied Continental forms, has led to the following conclusions. Some of the specimens will be figured on a future occasion.

The first remains of Pterodactyls discovered in this country were found by the writer, in the autumn of 1870, near the Smoky Hill River, in Western Kansas. These belonged to a gigantic species, which was described by the writer in 1871, and is now known as Pteranodon occidentalis. The geological horizon of these fossils was in the Middle Cretaceous, in the same deposits that contain the Odontornithes, or Birds with teeth. In the following year, additional specimens were secured by the writer in the same region, and referred to two new species of the same genus

The very full and able review of Dr. Sterry Hunt's paper on “The Geological History of Serpentine,”1 gives me an opportunity, of which I have been for some time desirous, of commenting on certain parts of it relating to my investigations of the typical rock which bears that name. In commenting adversely upon these, I must not be supposed to express a difference of opinion in regard to every part of the paper, because there are many relating to the Archæan schists with which I am in general agreement.

There can be no doubt that the name Megalichthys was originally suggested to Agassiz by the gigantic teeth of the great round-scaled fish first brought into notice by the researches of Dr. Hibbert, in the quarries of Burdiehouse, though indeed some of its remains had long previously been figured by Ure in his “History of Rutherglen and East Kilbride.” Incontrovertible evidence of this may be found by referring to the Proceedings of the British Association for 1834, and to Dr. Hibbert's original memoir on the Burdiehouse Limestone published in the Transactions of the Royal Society of Edinburgh, vol. xiii. 1835. But with the remains of this enormous creature were also associated and confounded certain rhombic glistening scales, belonging really to a considerably smaller fish of a totally different genus, and when Agassiz, subsequently to the meeting of the British Association at Edinburgh in the year above quoted, found in the Museum at Leeds a head of this latter form, or at least of an allied species, he adopted it, by description and by figure, as the type of his Megalichthys Hibberti, relegating the other to the genus Holoptychius. This latter, the real “big fish,” is now known as Rhizodus Hibberti, the founder of the genus being Prof. Owen; and though it may be a matter of regret that it did not retain the name Megalichthys, the laws of zoological nomenclature do not admit of any alteration now.

Next to Ananchytes ovata, there is probably no fossil Echinoid which is so well known to geologists and so common in collections as Galerites albogalerus, Lam. Described by Lamarck, studied by Forbes, and puzzled over by almost every naturalist who has classified the Echinoidea, this common yet most variable form has received a number of synonyms, and has been made to belong to four genera besides that in which it now rests.

That there is a wide-felt want, among field-geologists, of some rapid and sufficiently accurate method of solving such problems as arise in the ordinary course of their work is proved, if proof were necessary, by the summary of the literature bearing on this subject, given in the April Number of this Journal by Mr. Harker, who has certainly carried it to its highest point, for methods more simple than those given by him it is impossible to imagine. There is, however, a method, by which most of these problems can be solved by inspection without recourse to construction or calculation, which I would submit to the notice of geologists in general

The origin of metalliferous deposits has long been a subject of discussion. Professor Joseph Le Conte, however, seems to have arrived at a very decided opinion on this question, for in a contribution to the “American Journal of Science” (3rd series, xxvi. p. 1—19, July, 1883), after referring to Sulphur Banks and Steamboat Springs in California, he says: “Thus then subterranean waters of any kind, but especially alkaline, at any temperature, but mostly hot, circulating in any direction, but mainly upcoming, and in any kind of waterway, but mainly in open fissures, by deposit, form metalliferous veins.”

In the Geological Magazine for July, 1871, Plate VIII. pp. 289–294, I published an article on the above subject, giving my views of the appendages of Trilobites, and reproducing the figure of Asaphus platycephalus, Stokes, showing traces of eight pairs of locomotory appendages, discovered by Mr. Billings in the Trenton Limestone, city of Ottawa, and described and figured by him (in Quart. Journ. Geol. Soc. 1870, pp. 479–486, and plates xxxi. and xxxii.). I also appended a note to Mr. Billings's paper (op. cit. 1870, pp. 486–488) on a palpus of Asaphus from the same locality, which is as follows:—“Having been requested by Sir William Logan to examine the Trilobite sent over by Mr. Billings from Montreal, I was led to compare it with certain specimens in the British Museum collection, presented by Dr. J. J. Bigsby, F.R.S., some years since.

In the Geol. Mag. Dec. II. Vol. X. pp. 462–3, a Synopsis of the Genera of Fossil Phyllopoda was offered as a basis for the study of these interesting, though often obscure, little fossils, and some of the Bivalved forms, namely, Hymenocaris, Caryocaris, and Lingulocaris, were more especially noticed. See also “Report British Assoc.” for 1882. The univalve forms (excepting Dithyrocaris) have since then been carefully studied; and the classification proposed last year is found to hold good, with some slight modification, on comparison of all the species of which specimens or published figures have come to hand. Thus the term “flat-shield” is not strictly correct, for some of these carapaces are subconical or slightly convex; and one at least (Dipterocaris) is bent like a low ridge along the back: Pinnocaris is possibly really bivalved, without the triangular rostral piece; and probably Barrande's Crescentilla may be placed with Pterocaris and Dipterocaris.

The German Expedition to South Georgia has brought back the interesting information that this island, situated in the Antarctic Ocean, Lat. 54° S., Long. 37° W., is composed of clay-slate. Not only the part the members of the expedition were able to inspect was found to be composed of this slate-rock, but the glaciers brought down the same rock from the central portion of the island. In some places the slate was interspersed with varieties of quartz. No metals were found, but the rock contained a little iron, a quantity insufficient to affect the magnetic needle.

In the following pages a brief account is given of the organization and publications of the chief Geological Surveys in Europe. The statements are taken from official sources, or from an inspection of the publications.

In formation has been kindly supplied by the directors of the following surveys: — Austro-Hungary, Bavaria, Belgium, Italy, Norway, Saxony, Spain, Sweden, Switzerland.

In the preparation of this report my colleague, Mr. W. H. Dalton, has given me much assistance; my thanks are also due to Professor G. A. Lebour and to Mr. F. W. Rudler.

The “Geological Record” gives descriptions of maps published in and since 1874.

The following is an abstract of Dr. Hunt's paper. According to the author there is found among the pre-Cambrian strata of North America an invariable succession of crystalline stratified rocks, which have been by him divided into several great groups, the constituents of which become progressively less massive and less crystalline until we reach the sediments of Palæsozoic time; of which the Cambrian is regarded as the basal member. Since all of these pre-Cambrian rocks, with the exception, perhaps, of the lowest or fundamental gneiss, present evidences, direct or indirect, of the existence of organic life at the time of their deposition, it seems proper to include them under the general title of Eozoic, proposed by Sir J. W. Dawson. That of Archæsan, employed by some geologists to designate these pre-Cambrian rocks, appears too indefinite in its signification, and, moreover, is not in accordance with the nomenclature generally adopted for the great divisions succeeding. These Eozoic rocks include both the Primitive and the Transition divisions of Werner.

The Oyster-bed (Ostrea Bellovacina) in the lowest part of the “Woolwich-and-Reading” series is well known as constituting an interesting horizon in the Lower Eocene formation; but, as it is not throughout persistent in the range of this group of strata, every instance of its occurrence is worth recording. It is well known in Berkshire at Clay Hill, Shaw, about a mile N.E. of Newbury; and it occurs further westward near Hungerford (Prestwich, Quart. Journ. Geol. Soc. vol. x. pp. 85 and 87). We now know of its occurrence to the South of Newbury, from the works of the new railway intended to connect Newbury and Southampton.

The outcrop of the London Clay to the north of Southampton, near the edge of the Hampshire basin, beyond Bishopstoke, Romsey, etc., was mapped by the officers of the Geological Survey many years ago.

Recently, when examining some weathered fossiliferous limestone shale from the Lower Carboniferous strata of East Kilbride, Lanarkshire, my attention was attracted to some fragments of the valves of Spirifera trigonalis, Martin, in which I noticed, on the hinge-line of the dorsal valve, a row of small, round, hollow pits, and on the hinge-line of the ventral valve, a corresponding row of small, projecting, rounded denticles. These characters I had not noticed before, and on searching further, I found other fragments of the valves showing the same thing. This led to an examination of more perfect specimens of this Spirifera, contained in my own collection, and that of Dr. J. R. S. Hunter, of Braidwood, Carluke, and in one example, where the valves had slightly opened through pressure, on clearing away the shale, I found, on the outer edge of the ventral valve, a distinct row of small projecting denticles, that had evidently fitted into hollow pits or sockets in the dorsal valve, but from the way the valves had shifted in this specimen these were not seen. These denticles, when looked at externally, are nearly as numerous, and much of the same size, as those seen in many of the hinge-lines of shells of the genus Area, only in this genus, the teeth are the same in each valve, and lock into each other.