bluuebunny/crossref_metadata_2025 huggingface dataset:
On the Upper Beds of the Fifeshire Coal-measures
Authors: Binney Edw. W. , Kirkby Jas. W.
Published: October 2009

Overlying the profitable portion of the Fifeshire Coal-measures there is a series of red barren beds, of which we have not seen any description. Possibly Mr. Howell refers to similar measures, as occurring in Mid Lothian, in the Edinburgh memoir of the Geological Survey (pp. 110, 111); and since the date of that memoir an upper series of beds, evidently identical with that of Fife, has been recognized by the Geological Survey in Lanarkshire, and described as a separate subdivision (
d
5′) of the Coal-measures.

The best exposure of these red measures in Fife is on the coast from the mouth of the Leven to East Wemyss. Having somewhat carefully examined this section, we shall notice it briefly in detail —first as to the succession of strata, and afterwards as to the fossils found in them—and so give some account of the series.

The section in question forms part of the Wemyss coal-field, which, with the smaller adjoining fields of other lairds, is the most northerly piece of true Coal Measures existent in Britain. The dip of the strata is easterly, rarely exceeding 10°, generally less; and as the trend of the coast is north-east and south-west, a section in descending order is to be observed by traversing the shore from the Leven westward.
On the Cambrian (Sedgw.) and Silurian Rocks of Scandinavia
Authors: Marr J. E.
Published: October 2009

The classification of Prof. Scdgwick is quite applicable to the older palæozoic rocks of Sweden.

The boundary at the base of the equivalents of the May-Hill beds is marked by three distinct kinds of events: first, there is a physical break, as indicated by the absence of several beds at the summit of the Cambrian in various localities, and by the occurrence of conglomeratic beds at the base of the Silurian, resting unevenly upon the older deposits ; secondly, there is a palæontological break, which is more especially marked in the case of the deep-water beds; for although the various deep-water beds of Cambrian times have often species in common, or closely allied representative species, as have those of the Silurian also, there are very few common to the two systems ; thirdly, the trend of the coast-line in early Silurian times seems to have been totally different from that which existed in late Cambrian times, thus giving rise to a considerable difference in the direction of migration of the shallow-water faunas of the two systems.

Is there any other break of equal importance to this one in Scandinavia? Several authors have drawn a boundary at the base of the Ceratopyge-limestone, on palæontological grounds: there is no physical break there; and the value of the palæontological break may be estimated from the following remark of Dr. Törnqvist (Öfv. af K. Vet.-Akad. Förh. 1879, no. 2, p. 66) :—“ In Scandinavia the resemblance between the fauna of the Ceratopyge-limestone and that of the underlying beds is so great, that we have much difficulty in drawing a boundery between the primordial fauna and that which is usually styled Lower Silurian.”
Report on some Rock specimens collected by Mr. George Attwood in Costa Rica
Authors: Hudleston W. H.
Published: October 2009

Six specimens were carefully examined. Five of these are igneous rocks, having all the appearance of lavas; and although considerable differences exist between some of them, yet four out of the five, and perhaps all five, must come within the category of augite-andesites. The hand-specimens show a dark compact base with numerous crystals of felspars,
usually small
. Thus the general structure, viewed macroscopically, is micro-porphyritic. In most cases the felspars are inclined to be vitreous; but in one instance, where the crystals are rather larger, they are of a dull white.

The character of the ground-mass in thin section is seen to range from a trachydolerite, where there is a considerable development of microcrystalline matter, consisting for the most part of acicular prisms of triclinic felspar, to a rock in which the felsitic texture is in the ascendant and the tendency to doleritic texture is reduced to a minimum.

Generally speaking, the felspars are fresh, and polarize with considerable brilliancy. They are mostly triclinic, though not without orthoclase (sanidine) in some cases. Without analysis it is impossible to state positively what the triclinic felspars may be, though probably oligoclase is the most abundant. Judging from the analogy of similar rocks, andesine is also present; but the more basic varieties of felspar are probably rare or absent.
Thamniscus
: Permian, Carboniferous, and Silurian
Authors: Shrubsole George W.
Published: October 2009

The genus
Thamniscus
was founded in 1849 by Prof. King for a Polyzoan of large size found in the Permian beds of the north of England. The main interest of the genus consisted in Prof. King claiming for the type species the possession of certain “denticles,” “vesicles,” and “hemispherical bodies” similar to those observed in “certain Lunulites and
Cellaria salicornia
”. Prof. King further institutes comparisons between these peculiarities in his genus and some of the recent forms of Polyzoa formerly included among
Elasmopora, Escharina
, and
Cellepora
. It is needless to say that these features at once assign the genus to the order of Chilostomatous Polyzoa; and as such it is entitled to rank as the most pronounced type of its class found among the Palæozoic Polyzoa. How far these characters can be sustained will be the subject of after inquiry. The next reference to the genus that I find is in 1874, when Mr. R. Etheridge, Jun., described, as found in some Scottish Carboniferous Limestone shale, a fragment of a Polyzoan which he thought might be a new species of
Polypora
, at the same time remarking that the disposition of the cells and the mode of branching were exceedingly like those seen in the type species of
Thamniscus
(
T. dubius
, King), and suggesting that it might be a species of that genus.
On the Occurrence of a new Species of
Phyllopora
in the Permian Limestone
Authors: Shrubsole George W.
Published: October 2009

Among some Permian Polyzoa which Mr. Howse, of Newcastle, entrusted to me for examination was one labelled “Fenestella ramosa.” This I at once saw was not a
Fenestella
, but a
Phyllopora
, King, a new and, as yet, undescribed species.

The genus
Phyllopora
was rightly founded by King to receive the Permian and Silurian species of Polyzoa which, prior to that time, had been referred to
Retepora
. In accordance with this view Mr. Vine has recently shown that among the ancient Polyzoa, so far as at present ascertained, we have none of the peculiarities of cell-growth which are characteristic of the recent Reteporæ; in short, that we have no Retepores among the Palæozoic Polyzoa. All such so-called Retepores should be now assigned to
Phyllopora
, King. The genus
Phyllopora
has as yet been but imperfectly worked; its rarity in the more recent and its imperfect preservation in the older rocks go far to account for this. It is of interest as one of the earliest of our Palæozoic Polyzoa.
On a remarkable Dinosaurian Coracoid from the Wealden of Brook in the Isle of Wight, preserved in the Woodwardian Museum of the University of Cambridge, probably referable to
Ornithopsis
Authors: Seeley H. G.
Published: October 2009

Many years ago (about 1866) Mr. Henry Keeping obtained from the cliff at Brook, midway between the fossil forest at Brook Point and Brook Chine, at about 10 feet above high-water mark, the largest Dinosaurian coracoid which it has been my fortune to examine. It differs in important generic characters from the coracoid of
Iguanodon
; and the only genus hitherto described to which it is likely to belong, is
Ornithopsis
, a Saurian to which Mr. Hulke has already referred many bones of gigantic size.
Description of Part of the Femur of
Nototherium Mitchelli
Authors: Owen Richard
Published: October 2009

In my work on the Extinct Mammals of Australia the osteology of the existing species is described and figured in the degree requisite for the comparisons with the fossil bones.

In the Kangaroos the femur, amongst other characteristics, shows “the rough depression (plate lxxiii. figs. 2, 3,
y
, op. cit.) above the outer condyle (ib
v
)' and “the great transverse extent of the articular surface of that condyle by the production of its outer part, changing, there, the convexity into a concavity transversely (ib. fig. 2,
w
)”. With these may be noted the narrowness and depth of the postcondylar or popliteal fossa (fig. 2,
u
).

The corresponding part of the femur in the Wombats (ib. pl. ciii. figs. 1–4) differs in the absence of “the rough depression,
y
;” in the relatively less transverse extent of the articular surface of the outer condyle, especially at its back part; in the continuous transverse convexity of that part of the condyle, and in the minor relative depth and greater relative width of the postcondylar fossa.

In the comparison of the fossil femur of the
Diprotodon
(op. cit. pp. 231–234) the rough longitudinal depression above the outer condyle (pl. xxxiv. fig. 1,
o
), the concavo-convex hinder part of the articular surface of the outer condyle (ib.
v
) the length, depth, and relative narrowness of the postcondylar fossa (ib.
u
), with other characters of the bone, showed its closer resemblance to the femnr of the Kangaroo than to that of the Wombat or other of the larger existing kinds of Marsupialia.
Geological Age of the Taconic System
Authors: Dana James D.
Published: October 2009

A paragraph in the ‘Proceedings of the Geological Society’ for the 16th of November last, making part of an abstract of an address by Dr. T, Sterry Hunt sustaining the pre-Cambrian age of the Taconic schists, throws more doubt than is right on the stratigraphical observations that have been made in the region by different geologists. It does not present, as a reason for doubt, any facts from the authors personal investigation convicting these geologists of errors in their statements or conclusions, but simply mentions what the author regards as a possible source of error in any study of folded metamorphic strata, and urges this as a probable source in the present case.

The paragraph says:—“The speaker insisted upon the fact that where newer strata are in unconformable contact with older ones, the effect of lateral movements of compression, involving the two series, is generally to cause the newer and more yielding strata to dip towards, and even beneath the edges of the older rock, a result due to folds, often with inversion, sometimes passing into faults. This phenomenon throws much light on the supposed recency of many crystalline schists.”

The supposed recency of the Taconic schists, and the observations which have led to the inference that these schists
overlie
certain Lower Silurian strata, are among the points to which the paragraph is meant especially to apply. It implies that in any overlying, apparent or actual, it is
an overlying of newer strata, unconformably
.
The Rhætics of Nottinghamshire
Authors: Wilson E.
Published: October 2009

At the Meeting of the British Association at York in 1881 I gave a summarized account of the Rhætic rocks of Nottinghamshire. In the present communication I propose to give a more detailed description of the same.

Rhætic rocks were first noticed in this district about fifteen years ago near Gainsborough, in Lincolnshire, by Mr. F. M. Burton, and were subsequently observed at Newark by the Rev. A. Irving and by Mr. Horace Woodward, and at Elton Station, on the Nottingham and Grantham line, by Mr. E. Etheridge. All these sections, however, were more or less incomplete, either above or below.

During the last five or six years several new and some complete sections of the Rhætic beds have been exposed on the eastern and southern borders of Notts, chiefly by new railway-works. Unfortunately these sections are now all covered up and grass-grown. Seeing, however, that they disclosed several interesting facts and some new features concerning this series, a brief record of them appears desirable.
On Organic Remains from the Upper Permian Strata of Kargalinsk, in Eastern Russia
Authors: Twelvetrees W. H.
Published: October 2009

The cupriferous sandstones composing the Kargalinsk steppe, or steppe of Kargala, to the N. of Orenburg, lie out of the ordinary track of travellers, but offer an interesting field for research. The railway now takes us as far as the town of Orenburg, whence a drive of thirty or forty miles leads into the heart of the important mining district to which I now propose to invite your attention. The doubts thrown on the Permian age of these strata in the discussion upon my former paper induce me to submit a few remarks bearing upon the question.

The country is a grassy, treeless, undulating steppe, covered superficially with the well-known black earth, or tchernozem, considered by Murchison to be of marine origin. The balance of evidence, however, is in favour of it being a vegetable mould. Sluggish meandering streams intersect the steppe. The exposures of the subsoil on the banks of streams and ravines show nothing beyond red marl or sandstone devoid of fossils. The mine-borings and shafts cut down through red, yellow, and grey sandstones, and red and white marls, fossiliferous wherever the beds of copper ore exist.
On Chilostomatous Bryozoa from Biarnsdale (Gippsland)
Authors: Waters Arthur William
Published: October 2009

The present communication must be considered a continuation of my papers on South-west Victorian Chilostomatous Bryozoa (Quart. Journ. Geol. Soc. vol. xxxvii. p. 309) and “On Chilostomatous Bryozoa from Mount Gambler” (Quart. Journ. Geol. Soc. xxxviii. p. 257). The collection was lent me by Mr. J. R. Y. Goldstein, who, I presume, collected them himself from Bairnsdale; and it contains several very interesting specimens, though, in consequence of the other two collections of the same age being first described, the number of species not previously known fossil from Australia is only 14 out of a total of 42.
On the Silurian (and Cambrian) Strata of the Baltic Provinces of Russia, as compared with those of Scandinavia and the British Isles
Authors: Schmidt F.
Published: October 2009

I have recently completed the first part of a memoir upon the Silurian Trilobites of the Baltic provinces of Russia, containing a special geological introduction. This work is already in the hands of Silurian geologists. But as the subject of my memoir, and more particularly its geological introduction, may be of interest to British geologists in general, I will here endeavour to develop in English the most important results of my investigations, pointing out at the same time more especially some difficulties and controverted points in the parallelization of our Silurian strata with those of Scandinavia and the British Islands. There is no map accompanying my memoir; and the reader is therein requested to refer to the geological map of the Baltic provinces of Russia, published at Dorpat in 1878 by Prof. Grewingk. In this map the Silurian part was drawn by myself. The accompanying sketch (Pl. XXIII. fig. 1). will serve the purpose of the present paper.
The Newer Pliocene Period in England
Authors: Wood Searles V.
Published: October 2009

In the previous part of this Memoir, after describing the conditions under which the beds of the Red and Fluvio-marine Crag accumulated, and their overspread during a depression by the Chillesford Clay, I traced the progress of events from this time to the recession of the ice of the Major Glaciation, in the following order, viz.:—

The elevation and denudation of much of this Crag and Clay over all but their north-western, or most estuarine, extremity, and the formation at Kessingland, in North-east Suffolk, of a freshwater bed on one of the islands which came into existence by such elevation and denudation.
On
Helicopora
, a new Spiral Genus (with Three Species) of North-American Fenestellids
Authors: Claypole E. W.
Published: October 2009

The Silurian, Devonian, and Lower Carboniferous rocks of the Mississippi basin of the United States consist of thin limestones, and form altogether an insignificant mass when contrasted with the enormously thick deposits of the same age on the Atlantic border in Pennsylvania and the adjoining States, where the beds of corresponding age, composed for the most part of sandstones and shales, reach a thickness of from twenty to thirty thousand feet. Of these western limestones the Niagara group, the equivalent of the English Wenlock beds, has yielded a very rich harvest of fossil remains in almost all places where its beds are well exposed; but, being a typical dolomite, its fossils almost always occur as casts, the shells having been, except in very rare cases, removed by the percolation of acidulated water.

Among the fossils of the Niagara Limestone is a great abundance of fragments of various kinds of Polyzoa, especially of the family of Fenestellids, but in so broken and mutilated a condition that reference to species is impossible. Indeed there is room for believing that of the descriptions already published several may, in some cases, be founded on the same species.

During a residence of some years on the Niagara Limestone, at Yellow Springs, Green Co., Ohio, I obtained, among other Polyzoa, most of which were t~o imperfect for description, numerous specimens of a large and striking Fenestellid, quite distinct from every thing in the family already described, and yet showing features that fill an existing gap,and
On the Evidence of Glacial Action in South Brecknockshire and East Glamorganshire
Authors: David J. W. Edgeworth
Published: October 2009

Introduction

Evidences of glacial action seem to have been very little studied hitherto in this part of South Wales. Professor Ramsay, in the fifth edition of his ‘Physical Geology and Geography of Great Britain,’ merely mentions the occurrence of ice-scratched erratics all along the low ground of Glamorganshire north of the Bristol Channel, between Cardiff and Bridgend, and says that Boulder-clay is common her and there all over South Wales. Mr. A. Tylor has described glacial markings on the surface-rock at Hirwain Common, near Myrthyr Tydfil. No one, however, so far as the author is aware, has as yet attempted to work out the problems of these glacial phenomena in a connected manner. And yet few parts of Great Britain offer equal facilities of such a study. This is chiefly owing to the great development in South Wales of rocks so favourable to retaining marks of glaciation as the Millstone Grit and Pennant Rock, and to the fact that the length of their area is more or less transverse to the direction of glaciation. The Millstone Grit, cropping out to the north of the South-Welsh coalfield, runs east and west, without interruption, except at Caermathen Bay, from
1 1/2
mile S.W. of Abergavenny, in Monmouthshire, to within 2 miles of St. Bride's Bay, in Pembrokeshire. This band of Millstone Grit, 76 miles long, and from
1/4
mile to 2 miles in breadth, probably shows glacial markings at intervals throughout the greater part of its length. In Brecknockshire, even where it must have been
On the Dorsal Region of the Vertebral Column of a new Dinosaur (indicating a new Genus,
Sphenospondylus
), from the Wealden of Brook in the Isle of Wight, preserved in the Woodwardian Museum of the University of Cambridge
Authors: Seeley H. G.
Published: October 2009

This small series of six vertebral bones is remarkable for the great lateral compression of the centrum and the depressed form of the neural arch, and, as exhibiting the characters of the dorsal region in a new generic type, seems to me worthy of some notice.

The centrums of the vertebrae have an average length of 9 centim. each; the transverse width of the articular faces is about 7 centim., with a vertical depth of at least 8 centim.; but the lower part of the centrum is much compressed from side to side, so as to have a wedge form, and terminates inferiorly in a sharp longitudinal ridge. The articular margins of the centrums are moderately elevated. The transverse processes of the neural arch are at first directed backward, but soon become directed transversely outward, and retain their upward direction. The facet for the head of the rib is at first large, and at the base of the transverse process, and bounded posteriorly by the sharp ridge which runs below the transverse process to the hinder margin of the neural arch; but after a time the ribhead rises higher, so as to be chiefly above the zygapophysial facet; and then it becomes smaller, the ridge behind it more or less disappears or rounds away, and the transverse process, which was at first triangular in section, becomes vertically compresed and thin.

The interest of the series is in exhibiting the gradation of characters as the bones extend backward, though, as the
The Drift-beds of the North-West of England and North Wales.—Part II. Their Nature, Stratigraphy, and Distribution
Authors: Reade T. Mellard
Published: October 2009

Introduction

In Part I. of this paper, devoted to the “Shells of the Lancashire and Cheshire Low-level Boulder-clay and Sands ”, read before this Society in 1873, I discussed in outline some of the physical problems involved in a correct interpretation of the phenomena of the Drift as it is exhibited in Lancashire and Cheshire.

It is now my intention, by the aid of numerous sections I have been more or less continuously recording before and since that time, together with observations in other parts of England and in Ireland, Scotland, and Wales, to redraw my picture with a firmer hand. This delineation of the Glacial period in the north-west of England will rest almost entirely upon my personal observations ; but, at the same time, I shall not neglect those important additions to our knowledge contained in the Geological Survey memoir by Mr. C. E. De Rance, F.G.S.§ or the valuable papers by that untiring observer Mr. Mackintosh, F.G.S., by Mr. Shone,,F.G.S.w the late Mr. Binney, F.R.S., and others by Messrs Tiddeman, Goodchild, and the late Rev. Clifton Ward, published at various times in the Quarterly Journal of this Society. Neither will the more general papers by Mr. Searles Wood, jun., F.G.S., nor the work of Dr. James Geikie, F.R.S. be neglected where they bear upon the subject in hand and lend any help towards unravelling this most complicated and difficult problem.

River-Basins.

To describe in a manner that can be realized the distribution of the Drift-deposits,it will
On the Elasticity and Strength-constants of Japanese Rocks
Authors: Gray Thomas , Milne John
Published: October 2009

This paper contains a description of experiments made for the purpose of determining the different moduli of elasticity, and the strength against rupture and crushing of some of the more common Japanese rocks. One main object of the experiments was to obtain data for the calculation of the theoretical velocity of propagation of earthquake-waves, and by comparison of this velocity with the results of observation, to gain some idea of the degree of continuity in the strata.

The experiments on the moduli and the rupturing strength were performed on round columns of the rock about 4 centimetres in diameter and 60 centimetres long; those on strength against crushing were for the most part made on round columns 4 centimetres in diameter and 12 centimetres long.

The Young's modulus of elasticity was calculated from the results of experiments on cross bending, the columns being supported at both ends.

The modulus of rigidity was calculated from the results of experiments on the torsion produced by the application of measured twisting motives.

The bulk-modulus was calculated from the known relation between it and the Young's and rigidity-moduli.

The modulus of rupture was found by observing the load required to rupture the column by cross bending.

The experiments on crushing were performed by means of a Bramah's press, the pressure being estimated by means of a Bourdon's gauge.

The following Table (p. 140) gives the results of the experiments; the headings of the different columns sufficiently explain their contents.
On the Metamorphic and overlying Rocks in parts of Ross and Inverness Shires
Authors: Hicks Henry
Published: October 2009

I.
Introduction

Since I communicated my paper to the Geological Society in 1878, on the rocks in the neighbourhood of Loch Maree, Ross-shire, I have revisited the north-west Highlands on two occasions, viz. in the spring of 1880, and in the spring of last year. During these visits I devoted my time to the examination, in various areas, of sections which seemed likely to furnish evidence confirmatory or otherwise of the views which I had ventured to lay before the Society. In this paper I propose to give the general results obtained from these examinations, and to treat more fully those sections which appearm to offer any conclusive evidence. In each of the areas examined I made large collections of rock-specimens ; and numerous thin sections for examination with the microscope have been made from these rocks, and submitted for special examination to Prof. T. G. Bonney, and Mr. T. Davies. The former has kindly furnished the notes on these sections which are appended to this paper; and to both, on this as on so many former occasions, I am indebted for most valuable assistance in the petrological work. The notes by Mr. Davies in the paper I published in the Geological Magazine in 1880, on the Gairloch and Ben Fyn districts, have also so important a bearing on the questions discussed in this paper that I shall find it necessary to refer frequently to them.

The notes in that paper on the Gairloch specimens are particularly important, as they
On the Fossil Madreporaria of the Great Oolite of the Counties of Gloucester and Oxford
Authors: Tomes Robert F.
Published: October 2009

Introduction.—I have already in two communications brought before the notice of this Society some new or imperfectly understood Madreporaria from the Lias and Inferior Oolite, and have at the same time made additions to our knowledge of their stratigraphical distribution as well as to the localities where they have been met with.

In the present communication I propose to continue the series of papers on the same subject, in ascending order, and furnish some particulars not before noted respecting the Madreporaria of the Great Oolite of the counties of Gloucester and Oxford.

The following genera now appear as new to tho Oolite of this country.
Bathycœnia
is a new genus, and contains two species, which appertain to the family Astrædæ and tho subfamily Eusmilinæ.
Favia, Astrocœnia, Enallohelia,
and
Tricycloseris
are genera already established, the appearance of which in the Oolite of this country is now for tho first time recorded. Two other genera already made known by me as occurring in the Inferior Oolite are here added to the list of genera of the Great Oolite. They are
Confusastræa
, which is represented by two species, and
Oroseris
, which contains only one.

In my paper on the Madreporaria of the Inferior Oolite of the neighbourhood of Cheltenham, read before the Society in :May last year, I found it necessary to make some reforms in the nomenclature of certain species. This resulted from a more extended investigation into their mode of growth and increase; and it was seen that the two
On the Lower Eocene Section between Reculvers and Herne Bay, and on some Modifications in the Classification of the Lower London Tertiaries
Authors: Gardner J. S.
Published: October 2009

The Lower London Tertiaries were defined by Prestwich, as consisting of three divisions. Two of these were relatively homogeneous in composition; but the third was made up of very varied materials. The extreme care and accuracy with which these divisions were traced out over the whole of the Eocene area in England, and subsequently correlated with those of the French area, led to their speedy and universal recognition. No modifications in this classification were even suggested until 1866, when Mr. Whitaker, while unreservedly adopting Prestwich's divisions of “Thanet Beds” and “Woolwich and Reading Beds,” making, indeed, copious use of his observations, separated portions of his “basement-bed” of the London clay, where this was assigned any considerable thickness, together with a small portion of his Woolwieh and Reading beds, as “Oldhaven Beds,” and thus almost restricted the “basement-bed” to the inconsiderable thickness of coarser material which nearly everywhere forms the base of the London Clay. Almost the only criticism that can be urged against Prestwich's classification is that he places the “basement-bed” of the London Clay in a different group of the Eocenes from the London Clay itself, his nomenclature implying a closer relationship than he admits. But the Survey, on the other hand, have unfortunately adopted a name ( “Oldhaven ”) which not only does not exist on the maps, but is scarcely known at the locality, an inquiry for “Oldhaven Gap,” where the beds are typically developed, being useless even at the gap
On Gray and Milne's Seismographic Apparatus
Authors: Gray Thomas
Published: October 2009

The apparatus a description of which forms the chief subject of the present paper, is intended to give a complete record of the nature, magnitude, direction, and frequency of the motions of a point of the earth's surface during an earthquake, and at the same time to record the time of occurrence and the duration of the earthquake. The apparatus has been made by Mr. James White, Glasgow, and is to be used by Prof. Milne in his investigations as one of the committee appointed by the British Association for the investigation of the earthquake phenomena of Japan.

The instrument is suited for recording motions of the earth which are under one centimetre on either side of its normal position, while the period of oscillation is less than one second. The instrument may be adjusted to register motions having a longer period; but it is not expected to be called upon to do so. The actual motion of the earth is to be derived from a record of three separate components of the motion—two horizontal and at right angles to each other, and the other vertical. The horizontal components are recorded by a pair of conical pendulum-seismographs (see Phil. Mag. Sept. 1881), one of which is shown at P, figs. 1 & 2. These instruments are considerably simpler in form, and can be more readily adjusted, than the instruments described in the paper above referred to. They consist of cylinders of lead, P, supported from their centre of gravlty by
Additional Note on Boulders of Hornblende Picrite near the Western Coast of Anglesey
Authors: Bonney T. G.
Published: October 2009

In a short communication printed in this Journal (vol. xxxvii. p. 137) I described a large boulder of hornblende picrite which I found near Pen-y-Carnisiog in the autumn of 1880. Last summer I had an opportunity of spending an afternoon upon the western coast of Anglesey, and made use of it to examine the interesting section to the south of Porth Nobla. I did not, however, neglect to look out for boulders, as I thought it not impossible that I might meet with some more picrite. In this I succeeded beyond my expectations, and now lay the results before the Society, together with some remarks on the microscopic structure of the specimens collected.

After quitting the railway at Ty Croes Station, I walked a short
distance along the road to the south-west, and then turned up a
field-way leading past a small farm called Bryn Gwyn. A short quarter
of a mile from it a boulder (No. I.), perhaps roughly trimmed, has
been utilized as the capstone of a gate-post. It measures 2 3/4
× 2 × 1 1/4 feet.
A small fragment projected, which I was able to detach for examination without injury to the stone.

The next (No. II.) was a well-rounded boulder lying on the sandy shore at Perth Nobla. This had a rather greener matrix than those which I had previously seen: and the porphyritic hornblende or augite crystals were not quite so large. It measured about 2 feet each way, and rose about 1 foot above the
On the Supposed Pre-Cambrian Rocks of St. David's
Authors: Geikie Archibald
Published: October 2009

Introduction

Some explanation is required of the grounds on which another contribution is added to the already voluminous literature connected with the rocks of St. David's. The circumstances under which I have reluctantly found myself compelled to make this contribution are briefly these.

A new edition of the Rock Catalogue of the Museum of Practical Geology, Jermyn Street, being required, it became necessary to ascertain how far the stratigraphical order followed in previous editions required to be modified by the results of more recent research. In particular, the question of the existence of Pre-Cambrian rocks in Wales, which has emerged since the last issue of the Catalogue, appeared to demand full recognition in any republication of the work. I felt it to be due to those authors who have written so largely on this subject that ample acknowledgment of the results of their labours should be given. On the other hand, I was equally desirous that in admitting corrections of the views expressed upon the maps and sections of the Geological Survey I should do so from an actual inspection of the ground, which would enable me to judge how far and in what manner the required alterations should be made.

It was obvious that in maps of districts surveyed forty years ago some important structures might have escaped notice, positive errors might have been committed, and petrographical details could not be expected to have been treated in a more satisfactory manner than in other English geological works of the same
On the Skull of
Megalosaurus
.
Authors: Owen Richard
Published: October 2009

Since the description of the fossils on which the genus and species (
Megalosaurus Bucklandi
) was founded, the additional specimens have been, mainly, parts of the trunk and limbs. To the mandibular and dental fossils have been added two portions of the upper jaw, now in the Oxford Museum, on which Professor Phillips has founded the restoration of the skull given in Diagram lvii. of his ‘Geology of Oxford’.

Acceptable, therefore, were the additional cranial and dental evidences obtained by Edward Cleminshaw, Esq., M.A., F.G.S., of Greenhill, Sherborne, Dorset, from the freestone of the ‘Inferior Oolite,’ near Sherborne J. Blocks of this stone were in course of preparation for a building, when, indications of imbedded fossils being detected by Mr. Cleminshaw on fractured surfaces of the quarry-stones, he withdrew all such from the building-yard and transmitted them to the British Museum for identification.

Further requisite development of these remains having been there carried out, the following descriptions and drawings are now submitted to the Geological Society.

In the section devoted to the genus Megalosaurus in vol. i. pp. 329-354 of the undercited work w the materials for a reconstruction of the skull were limited to portions of the mandible and divers teeth therein implantcd or detached. The most instructive of these was a portion of the lower jaw, in the collection of His Grace the Duke of Marlborough, from the same formation (Oolitic Slate, Oxford) as that which had afforded Buckland the materials for the species which
On the Basalt-Glass (Tachylyte) of the Western Isles of Scotland
Authors: Judd John W. , Cole Grenville A. J.
Published: October 2009

In a previous paper* it has been pointed out that the Tertiary volcanic rocks of the Western Isles of Scotland offer beautiful examples of materials of every variety of composition, from the most acid to the most basic, and of every type of structure, from the holocrystalline to the vitreous. The detailed description of these varieties of volcanic rocks was reserved for a future occasion ; and in the present paper we propose to give the first of such a series of descriptions. As the more acid vitreous rocks have during recent years been discussed in considerable detail in numerous papers read before this Society, it may not be inappropriate to direct attention to the rare but equally interesting glasses of basic composition, which have, up to the present time, received far less notice in this place. The studies on which this paper is based have been carried on in the Geological Laboratory of the Normal School of Science and Royal School of Mines.

1.
History of Previous Opinion on the Subject
.

By the older writers on petrography rocks of the kind of which we now treat appear to have been classed as “pitchstones.” Jameson and the other followers of Werner, who endeavoured to introduce the precision of nomenclature and the exact methods of their master into the study of British rocks—though they recognized these materials, not as minerals but as rocks—do not seem to have discerned the difference between the acid and basic
On a Section recently exposed in Baron Hill Park, near Beaumaris
Authors: Bonney T. G.
Published: October 2009

In the autumn of 1880 I observed by the roadside leading up the hill from the gates of the Beaumaris Cemetery towards Llandegfan some peculiar grits which reminded me much of certain beds exposed in the district near Perfeddgoed House and other places in the neighbourhood of Bangor. The rock, which crops out here and there by the roadside (perhaps about one third of a mile from the road to Menai Bridge) varies from a green “bastard” slate to a grit containing small grains of reddish felsite. These beds are succeeded, after a very short interval, by the normal greenish micaceous or chloritic schists of the region. Although convinced that this indicated an extension of the group of beds which in the Bangor area underlie the conglomerate now generally taken as the base of the Cambrian, such specimens as I could obtain might not have convinced others, and I waited for a more favourable opportunity of examining the district. Last summer, while on a visit to some friends in the neighbourhood, I was informed by them that a new drive was in process of construction through the woods on the face of the hill mentioned above; and I applied, as the grounds of the Baron Hill estate are strictly private, to the owner, Sir R. Williams Bulkeley, for permission to examine the sections. This was at once accorded to me most courteously, and the results proved even more interesting than I had anticipated.

The new drive is carried along the face of
On the Rocks between the Quartz-felsite and the Cambrian Series in the Neighbourhood of Bangor
Authors: Bonney T. G.
Published: October 2009

This district has already been the subject of papers published in the Quarterly Journal of the Society. The authors of these agree in accepting the coarse conglomerate exposed (for instance) on the upper part of the hill pierced by the eastern tunnel of the railway near Bangor, as the base of the Cambrian; but there is still some diversity of opinion as to the relations and extent of the subjacent series. The views on the latter point will be found respectively expressed in papers by myself and Professor Hughes in vol. xxxv.; and since the publication of the latter I have four times revisited the district, leaving, I believe, but few exposures of the rock unexamined (except such as may occur unknown to me in private grounds). As I adhere to my original opinion as to the sequence of the beds, I now ask leave to state as briefly as possible the additional evidence which I have succeeded in gathering. At the same time I am glad to take this opportunity of frankly admitting that in the part of his paper which treated of the relations of the conglomerate and the granitoid rock at Twt Hill I was wrong, and Prof. Hughes was substantially right. Repeated examination of the district and of specimens under the microscope has convinced me that, notwithstanding the apparent passage of the one into the other, the conglomerate is much later in date than the granitoid series. Whether it be of the same date as the
On the alleged Existence of
Ovibos moschatus
in the Forestbed, and its Range in Space and Time
Authors: Dawkins W. Boyd
Published: October 2009

1.
Introduction
.

The specimen which forms the subject of the present notice formed part of the collection of the late Rev. F. Buxton, and was sent to me for identification by his brother, :Mr. A. F. Buxton, in April 1883. It was obtained by u fisherman from the Forest-bed of Trimingham, four miles from Cromer, in Norfolk, and may .be inferred to have been discovered in situ, since its edges and processes are sharp and fresh, and the red matrix is still adherent in places. Had it been a waif and stray on the beach, ig would have been water-washed and more or less abraded, as is invariably the case with beach-specimens cast up by the waves.

2.
Description and Identification
.

It consists of the posterior half of the upper surface of the skull (see figure), comprising part of the occipital, the whole of the parietals and frontals with the basal portion of the two horn-cores, the posterior half of the left orbit, the lacrymals, and fragments of the maxillaries. The measurements of the various parts are given in the accompanying table in the first column in inches and tenths.

On comparing the skull from Trimingham with the fossil skulls from various deposits in Britain, which have been described in my monograph on
Ovibos moschatus
, as well as with the recent skulls in the British Museum and the College of Surgeons, from the Arctic regions, it is at once obvious that it belongs to the same series and is specifically
Notes on a Collection of Fossils and of Rock-specimens from West Australia, north of the Gascoyne River
Authors: Hudleston W. H.
Published: October 2009

This collection was made by Mr. Forrest, the colonial surveyor, and forwarded by him together with the accompanying map to Sir Charles Nicholson, by whom the specimens were placed in the hands of Dr. Gwyn Jeffreys for determination. Dr. Jeffreys brought the parcel over to the apartments of the Geological Society, and it was suggested that I should undertake to examine and report upon them. Being quite unaware that the whole of the fossils were palæozoic, including several species of Polyzoa and Actinozoa, I somewhat rashly undertook a task which, as regards the palæontology, it would have been impossible for me to have fulfilled, but for the kind assistance of Professor Morris and Mr. Robert Etheridge, junior, to both of whom my acknowledgments and best thanks are due.

It will scarcely be necessary to refer in detail to the literature of Australian geology on the present occasion. A full list of all the works bearing on the subject is be found in the catalogue by Messrs. Etheridge and Jack, whilst the former gentleman's catalogue of Australian fossils, published at the Cambridge University Press in 1878, is indispensable to any one who takes up this question. There are two works, however, that may be specially mentioned, viz., Strzelecki'.s ‘New South Wales’ &c., with notes on the fauna by Lonsdale and Morris, published in 1845, and De Koninck's ‘Rccherehes sur les fossiles paléozoiques de la Nouvelle GaUcs du Sud,’ published in 1876–7. The Quarterly Journal of the Society contains a most
Notes on the Geology of the Troad. A brief Summary of the Results derived from the Observations made in connexion with the Assos (U.S.) Expedition
Authors: Diller J. S.
Published: October 2009

The terranes of the Troadic peninsula comprise a variety of stratified and massive or eruptive rocks. The former, excepting the most recent deposits, which are not considered in this connexion, may he divided into three groups according to their mineralogical conditions and geological age.

The most ancient group is highly crystalline and, in all probability, belongs to the so-called mica-schist zone of the “Grundgebirge” or Archæan formation.

The youngest group, embracing the Miocene and Pliocene Tertiary deposits, is, at least in part, well characterized by its fossils.

The middle group is defined by the widely separated limits of the other two groups. It embraces rocks which may be Palæozoic or Prepalæozoic, as well as others which are probably of Cretaceous and Eocene age.

Crystalline Schists
.—The crystalline schists have their greatest development in Mount Ida, of which they form almost the entire mass. They are of many varieties, all conformably interstratified, as if belonging to the same great terrane.

True gneisses are not abundant, and occur chiefly upon the north side of Mount Ida, under such conditions that they appear to overlie the schistose rocks. In Hadji-eulduren-dagh the mica is in large part replaced by hornblende, so that the gneiss has a dioritic aspect.

In the schistose rocks (chiefly amphibolites) hornblende is one of the most widely distributed and abundant minerals. It generally appears as actinolite, and not unfrequently constitutes almost the whole of the rock in which it occurs. With amphibole are associated, besides felspar, at times more or less
Notes on Brocchi’s Collection of Subapennine Shells
Authors: Jeffreys J. Gwyn
Published: October 2009

H
aving
lately passed through Milan on my way to Venice, I took the opportunity of examining the collection of fossil shells made by Professor Brocchi and described in his classical work ‘Conchiologia fossile subapennina’. That remarkable work was published in 1814, when the study of palæontology was almost in its infancy. It was based on the Linnean system and nomenclature.

Giovanni Battista Brocchi was not only a celebrated geologist but also a botanist, an entomologist, and an antiquary. His first essay was on Egyptian sculpture, and was published at Venice in 1792, when he was only 20 years old. His other works on different subjects were about fifty in number. In 1802 he was appointed to the chair of natural history at Brescia, and he afterwards became Inspector of Mines in Lombardy. He died in 1826, at the age of 54.

The first volume of the ‘Conchiologia’ contains an interesting introduction, an elaborate treatise on the progress of the study of fossil conchology in Italy from 1300 to 1811, and geological remarks on the Subapennine and adjacent formations. The second volume is devoted to the enumeration and description of the fossil shells, and is illustrated by 16 well-executed copper plates. The ‘Conchiologia’ is a monument of careful and conscientious labour, and is invaluable to every palæontologist.

The collection was shown to me, in the absence of Professor Stoppani, by Signor Francesco Molinari, an assistant at the Civico Museo of the Reale Istituto, whose courteous attention I am glad to acknowledge.
The Geology of Monte Somma and Vesuvius, being a Study in Vulcanology
Authors: Johnston-Lavis H. J.
Published: October 2009

T
he
general form and outline of Monte Somma, the relation of the cone of Vesuvius piled around the recent eruptive axis, to that of the prehistoric one, have been so often alluded to by various authors, that the subject might appear exhausted.

If Monte Somma is viewed from the north, for example from the bridge at Marigliano, it presents to the view certain characteristics of many volcanic cones. Its eastern and western flanks rise from the fertile Campanian plain at a gradually increasing angle, until at an average of 1050 metres of altitude, the outline becomes horizontal, presenting an irregular crenated ridge. In fact it exhibits that symmetry of form so characteristic of many truncated volcanic cones.

If the observer has chosen the early morning, the sunlight falling obliquely across the face of the slopes brings out in all the detail of sharply cut light and shade, the ravines or valleys with which the mountain sides are scored.

As the observer winds round the base in a westerly direction, the above-described apparent regularity disappears. From Naples, which lies very nearly west of Somma, the line of truncation is seen to slope from the Punta del Nasone 1137 metres, the highest point on the northern ridge, to the Pedimentina, 650 metres, the summit of the old crater-ridge on the southern side. This curve is concave downwards, and of irregular outline. It marks the edge of the great crater that was excavated by one, or a series of eruptions, which culminated in