bluuebunny/crossref_metadata_2025 huggingface dataset:
On a probable Palæolithic Floor at Prah Sands (Cornwall)
Authors: Reid Clement , Reid Eleanor M.
Published: October 2009

About 7 miles cast of Penzance a shallow bay lies between a rocky headland of slate and elvan on the one side, and the Godolphin granite on the other. Into this bay sand, principally shell-sand, has drifted, so as to show at low tide a mile or so of sandy foreshore, behind which occur low cliffs and sand-dunes. This tract is known as Prah Sands. In its leading characteristics it is a typical Cornish bay, dating from the period of the raised beach, but subsequently rendered less important, and partly obliterated, by changes of sea-level and the accumulation of drift.

The drift "in the low cliff at Prah was described in 1879 by Mr. W. A. E. Ussher; but nothing exceptional seems to have been visible at that date, nor was anything unusual observed during two visits made by one of us in 1901. The ordinary Succession of angular ‘head,’ on raised beach, resting upon a wave-worn rocky platform, was all that was noticed.

During the severe gales of 1902 and 1903 the sea washed away much of the talus and sand which masked the foot of the cliff between Sydney Cove and Hoe Point, and also removed so much of the beach as to lay bare numerous patches of the rocky floor below. The sections thus exposed are of such great interest as to justify a detailed description, for they yield what we believe to be the first evidence of Palmolithic man yet found in Cornwall.

The section lies
On the Jaws of
Ptychodus
from the Chalk
Authors: Woodward Arthur Smith
Published: October 2009

In 1887 I pointed out that the teeth of
Ptychodus
from the Chalk were arranged in the mouth not like those of the Cestraciont sharks, but rather like those of some of the Myliobatid rays. This arrangement has subsequently been observed in new specimens, both in England and America. Hitherto, however, no traces of the cartilaginous jaws have been found in association with the dentition, and their shape and relations have thus remained unknown. Quite lately, a new specimen, partly showing the jaws, has been obtained from the Lower Chalk of Glynde by Mr. Henry Willett, and he has kindly submitted it to me for study, to supplement my former description, which was chiefly based on the Willett Collection in the Brighton Museum.

The new fossil evidently belongs to a small variety or young individual of
Ptychodus decurrens
, the species previously discussed, and its principal characters are shown in the accompanying plate (XV). It comprises fragmentary remains of both jaws, each bearing many of the characteristic teeth arranged in their natural order. The rami of the jaw which may be identified as mandible (Pl. XV, figs. 1 & 2,
md
) are remarkably slender, and meet in an acute angle at the symphysis, which is shown to have been elongated, though it is disintegrated by the formation and oxidation of iron-pyrites. The upper jaw or pterygo-quadrate cartilage (fig. 2,
ptq
) is represented only by shapeless fragments. The dentition is confined exclusively to the symphysial region, where the teeth are arranged in
On the Igneous Rocks at Spring Cove, near Weston-super-Mare
Authors: Boulton William S.
Published: October 2009

I. I
ntroduction
.

In the Summary of Progress of the Geological Survey for 1898 (pp. 104–11), Sir Archibald Geikie & Mr. Strahan, in a description of a ‘Volcanic Group in the Carboniferous Limestone of North Somerset,’ published for the first time the evidence for the contemporaneity of these igneous rocks. The authors refer briefly to the basalt and associated tufts at Spring Cove, immediately to the west of the town of Weston, and describe in more detail the basalt-lava and beds of tuff interbedded with the fossiliferous limestone along the ridge of Middle Hope, 2 miles north of Weston.

At the time of the publication of this account, I had already made a detailed examination of these rocks in the field, and of microscopic and chemical preparations ; but as my results seemed in general accord with those of the authors named, especially in regard to the rocks of Middle Hope, I felt that little or nothing was to be gained by the publication of my work as a whole.

In the rocks at Spring Cove, Weston, however, there appear to me to be points of considerable interest which are only briefly touched upon, or not mentioned at all, in the account to which I have referred, and I therefore venture to submit some additional observations in regard to them.

II.
General Description of the Rocks
.

The basalt at Spring Cove, immediately north of Weston Pier, runs obliquely to the high road, and is exposed from low-water mark along the foreshore
The Rhætic Beds of the South-Wales Direct Line
Authors: Reynolds Sidney Hugh , Vaughan Arthur
Published: October 2009

I. I
ntroduction
.

The Rhætic Beds of the South-Wales Direct Line have been briefly described by the following geologists:—

1.

Mr. H. B. Woodward, in the ‘Summary of Progress of the Geological Survey’ for 1898, p. 191.

2.

The Rev. H. H. Winwood, in the Report of the Excursion of the Geologists Association to the new Great Western Railway-line from Wootton Bassett to Filton, Proc. Geol. Assoc. vol. xvii (1901) p. 148.

3.

Mr. A. Strahan describes the Lilliput section in the ‘Summary of Progress of the Geological Survey’ for 1902, Appendix V, p. 192.

4.

Mr. A. Rendle Short describes the Stoke-Gifford section in a paper read before the Geological Society on December 16th, 1903, and now published in the same part of the Quarterly Journal as the present, paper.

II. D
escription
of
the
E
xposures
.

The Rhætic Beds are finely exposed in the large cutting near Stoke Gifford; they come on above the Kcuper rocks west of the Carboniferous-Limestone outcrop at Lilliput Farm, and an excellent section occurs resting upon the Carboniferous Limestone, from Lilliput Bridge as far east as Chipping-Sodbury railway-station.

(a) The Stoke-Gifford Section.

As Mr. Rendle Short informed us that he was engaged on a detailed examination of the Stoke-Gifford Rhætic, we have conlined ourselves to a general account of the section, and have only included the results of our independent observations in this paper. Had we omitted all reference to the Stoke-Gifford section, our
The Derby Earthquakes of March 24th and May 3rd, 1903
Authors: Davison Charles
Published: October 2009

As a seismic region, Derbyshire is marked by few earthquakes, though parts, and even the whole, of the county are occasionally disturbed by shocks from other British centres. To find one that will compare in strength with the principal subject of this paper, we must go back more than a century, to November 18th, 1795, when a shock was felt over a district reaching in one direction from Leeds to Bristol, and in the other from Norwich to Liverpool. The dimensions of the disturbed area are given by Dr. E. W. Gray, F.R.S., as about 165 miles from norta to south, and about 175 miles from east to west. ‘In this latter direction, or rather from north-east to south-west,’ he remarks, ‘it may be said to have reached nearly across the island.’ The area disturbed cannot have been less, and may have been much more, than 23,000 square miles; while, if we may judge from the places where chimneys were wholly or partly destroyed (Derby, Chesterfield, and Ashover), the epieentre may have coincided approximately with that of the principal earthquake of 1903.

In another respect there seems to have been a close resemblance between the two shocks. It is probable from Dr. Gray's account (
op. cit.
p. 365), that the earthquake of 1795 was what I have termed a ‘twin’-earthquake, that it consisted of two distinct parts separated by a very short interval of rest and quiet. That this was a characteristic feature of the earthquake of 1903 was evident
Appendix I. Notes on the Collection of Rock-specimens made by Col. English in European Turkey and Asia Minor
Authors: Flett John Smith
Published: October 2009

The collection of specimens submitted to me by Col. English, though not very large, included representatives of many different kinds of rocks—sedimentary, igneous, and metamorphic. The most numerous, however, were the recent lavas, which ranged from rhyolites and trachytes to very basic augitites. Many of the specimens, having been collected in the course of hurried traverses through difficult regions, were not so fresh as might have been desired. Yet it was possible, in nearly all cases, to form a definite opinion regarding the nature of the rock and the group to which it was to be assigned.

The clastic sediments and organic limestones of the Tertiary Series require no special description, but mention may be made of the occurrence of red, baked, and hardened, nodular shales, which had been contact-altered apparently by lava-flows that covered or enveloped them. None of the advanced stages of thermal alteration were found in any of the rocks sliced. Trachytic (?), andesitic, and basaltic tuffs were numerous, but call for no detailed treatment.

The assemblage of crystalline, igneous, and metamorphic rocks was on the whole very similar to that which has been described by J. S. Diller from the adjacent district of the Troad. With the exception of the nepheline-basalts, practically all the rocks described by him were present also in Col. English's series; and there were only one or two classes the occurrence of which was not already known from Mr. Diller's paper.

Rhyolites were certainly few, although they are reported as abundant in
Notes on the post-Tertiary and Tertiary Fossils obtained by Col. English from the District surrounding the Dardanelles
Authors: Newton Richard Bullen
Published: October 2009

Considerable, interest may he attached to the fossils collected by Col. English in a number of localities surrounding the Dardanelles,since many of the specimens rank as fresh records for this part of South-Eastern Europe. One of the most important results accruing from an examination of the eoilection has been the fixing of the age of the coal-deposits at Masatly, which can now be referred to the Stampian or Middle division of the Oligocene System, on account of the discovery of
Corbicula semistriata
in those beds at that locality, in association with
Anthracotherium
-remains.

The specimens are scheduled under the following formations:--

The whole of the collection has been generously presented to the British Museum (Natural History) by Col. English.

Post-Pliocene.

Marine mollusca found in the region of the Dardanelles have been identified with existing Mediterranean species. Hence, the deposits containing them may be recognized as of post-Pliocene age, and probably of contemporaneous origin with those found in Cyprus (as known to us through the researches of Prof. Gaudry), and in the Hellespont by Calvert & Neumayr.

(A) List of marine shells from the coast-cliffs west of Gallipoli, 40 to 100 feet above sea-leveL

(B) A marine shell from Gallipoli Ovassi, about one mile north-east of Gallipoli, in a loamy clay-bed 20 feet above the sea.

(C) List of marine shells from the other side of the Dardanelles opposite Gallipoli, about 1 mile inland from Tchardak. The beds containing this fauna are of a sandy character, and nearly 50 feet above sea
Notes on Nummulites in the Turkish Rocks described by Col. English
Authors: Holland Richard
Published: October 2009

There appear to be at least three species of nummulites (giving six forms) in the rocks from Vernitza. These are:-

1. (Pl. XXV, figs. 1-3.) A large nummulite having a width of from 45 to 50 millimetres, and a thickness of from 5 to 10 mm.It is microspheric, and there are eleven to twelve turns of the spiral in a radius of 3 mm. The f i l e t s cloisonnaires are sinuo-striate and delicate. The chamber-ratio is
irregular:
The History of Volcanic Action in the Phlegræan Fields
Authors: de Lorenzo Giuseppe
Published: October 2009

I. INTRODUCTION.

The scene that discloses itself to the observer who enters the Bay of Naples by the so-called Boeca Grande, presents three parts, each characterized by distinct features. On the right, masses of calcareous pink and white rock rise up into the Island of Capri from the foam-flecked waters of the Mediterranean, and stretch through Sorrento and Amalfi to the cloud-capped Apennine. On the left, a vast succession of undulating ridges of tawny-coloured tuff begins, first at the Island of Ischia, and then, extending through Vivara and Procida, spreads out into the gentle declivities upon which Naples is built. In the central background looms grand and solemn the smoking peak of Vesuvius.

Just as these three components of the landscape are diverse in aspect, so too are they diverse in geological origin and constitution. The island of Capri and the peninsula of Sorrento are made up of a gigantic pile of dolomitic and calcareous deposits of Upper Triassic (Hauptdolomit) and of Cretaceous (Urgonian-Turonian) age.Upon these rest in places a tbw insignifcant patches of Eocene-Miocene Flysch. Vesuvius is a typical volcano of concentric accumulation (vulcano a recinto), almost entirely built up of leucotephritic, fragmental, and lava-form materials. Between Naples and Ischia lies a vast and complex assemblage of extinct craters, which have erupted much fragmental material but little lava, generally of a trachy-andesitic character, though exceptionally the crater of Vivara has disgorged a basaltic magma.

This region, more especially that portion of it lying between Naples, Cuma, and Miseno,received from
On the Occurrence of a Limestone with Upper Gault Fossils at Barnwell, near Cambridge
Authors: Fearnsides William George
Published: October 2009

In the course of a recent examination of the great Gault-pit worked by the Cambridge Brick Company, Ltd., at Barnwell, my attention was drawn to an unusual and inconstant hard bed which is occasionally met with in the lowest part of the pit.

On examination, the hard material was found to consist largely of comminuted
Inoceramus
-fragments, with occasional ammonites and other shells, and a careful search ill this and the adjoining clay proved them to be quite fossiliferous. Unfortunately, the specimens obtained are only fragmentary, but as they seem to indicate a horizon higher than any yet recorded from the Cambridgeshire Gault, they may perhaps be worthy of record.

The section now seen is as follows, in descending order :—

Of these, the three lowest divisions are the most interesting, and nearly all the fossils come from the beds (4)and (5). The Hard Band (4) is extremely variable in thickness. It occurs in a series of flattened lenticles, generally a few yards in diameter and up to a foot in thickness. It is largely made up Of broken shells and phosphate-nodules, with a few bone-fragments and extraneous pebbles of mud, and is harsh to the touch. Some of the ammonites and
Inocerami
are very large, and specimens of the latter 3, 4, and even 5 inches across are not uncommon.

Petrologically, the Hard Band is best described as a somewhat muddy shell-limestone. It contains abundant phosphate-nodules, of which at least three types occur: these we may distinguish as the green,
On the Age of the Llyn-Padarn Dykes
Authors: Elsden James Vincent
Published: October 2009

I.
INTRODUCTION.

The characters of the basic sills of Caernarvonshire have been described in detail by several writers, notably by Mr. ttarker in his well-known essay on the Bala Volcanic Series. There is a marked absence of dykes in association with the outbursts of this period, and the numerous basic dykes of this area have generally been assigned to a later series of eruptions. The evidence upon which this assumption rests is, however, not always satisfactory; and although Mr. Harker is inclined to favour their post-Carboniferous age, he does not conceal the uncertainty of this conclusion in several eases, and he adduces evidence which seems to point, at least in some instances, to the possibility of the existence of more than one group of these intrusions. Dr. C. A Matley, also, finds that in Northern Anglesey at least two groups of dykes occur, of which the earlier are pre-Silurian and the later post-Ordovician But Mr. E. Greenly maintains that the later dykes of Anglesey, including those of the Menai Straits, are certainly post-Carboniferous, and may possibly be evea of Tertiary age.

With regard to the Llyn-Padarn dykes, with which this paper is ciliefly concerned, no very detailed description appears to have been published, although several authors have incidentally referred to them, as will be mentioned hereafter. It appears to have been generally assumed that these dykes are of the same age as those of the Menai Straits, to which they are supposed to bear a general resemblance, both, in petrographical
Eoscorpius sparthensis
, sp. nov., from the Middle Coal-Measures of Lancashire
Authors: Baldwin Walter , Sutcliffe William Henry
Published: October 2009

I.
LOCALITY AND HORIZON OF THE TYPE-SPECIMEN.

If reference be made to Sheet 88 of the Geological-Survey Map of Great Britain, it will be seen that a portion of the Middle Coal- Measures is repeatedly thrown in, between Rochdale and Heywood, by several large faults, so as to form two isolated patches and two large promontories jutting out northward from the general range of the Middle Coal-Measures. About half a mile to the south-west of Rochdale Town-Hall there is, at an elevation of 400 feet above Ordnance-datum, an isolated eminence at Sparth Bottoms, which is fast disappearing, as the shale is being excavated for the purpose of making bricks.

This eminence is situated almost in the centre of one of the before-mentioned promontories: At this point several beds of greyish-blue shale, containing clay-ironstone nodules, crop out; and there is also a bed a few inches thick, with nodules containing for the most part well-preserved remains of
Carbonicola acuta
. These beds dip in a south-westerly direction. The
Carbonicola
-bed may perhaps be taken as a fairly-constant horizon above the Royley or Arley-Mine seam, since we have found it in Dawson's Wood, about a mile distant, and have calculated that it occurs about 135 feet above the Royley-Mine coal-seam.

These beds have yielded remains of well-preserved ferns,
Calamariece, Sigillarioe
, and fine specimens of Merostomata, both
Prestwichia rotundata
and
Belinurus bellulus
have been found here. A nodule which was found, in October of last year, about 8 feet above the
Carbonicola
-bed had added a
The Igneous Rocks of Pontesford Hill, Shropshire
Authors: Boulton William S.
Published: October 2009

I.
INTRODUCTION AND PREVIOUS LITERATURE.

PONTESFORD HILL is sit.uated on the north-western flank of the Longmynd range of Shropshire, about 7 miles south-west of Shrewsbury. With a length of about a mile, and a breadth of half a mile, it rises to a height of just over 1000 feet, and from its summit, which is the site of a well-preserved Roman camp, a fine view of the surrounding country is obtained. A mile to the west, and running through the village of Pontesbury, the Stiper- Stones Quartzite, the local base of the Ordovician System, crops out; while to the south-west stretches nearly the whole sweep of the Ordovician district of Shelve and the Corndon. Immediately to the east and south rise abruptly the conglomerates and purple grits of the Western Longmynd, making up the conspicuous woody ridges of Radlith and Oakswood. Between these and Pontesford Hill is a deep and picturesque wooded gorge, cut by the Habberley Brook. Here, about a third of a mile east of the northern end of Pontesford Hill, is the Lyd Hole, a big, circular pot-hole, at and near which are some conspicuous exposures of rocks referred to by :Mr. Blake and Dr. Callaway in their papers dealing with the geology of the district. Northward stretches the great plain of Shrewsbury and Chester.

The hill, which is nearly severed into two roughly-equal portions by a north-eastern and south-western galley, rises from the valley with abrupt and steep slopes, but with a general rounded outline. One
The Leicester Earthquakes of August 4th, 1893, and June 21st, 1904
Authors: Davison Charles
Published: October 2009

I. I
ntroduction
.

T
hough
an interval of nearly eleven years separated the Leicester earthquakes of August 4th, 1893, and June 21st, 1904, the two shocks were so closely related in their origin that it is convenient to regard them as members of a single series. The earthquake of 1893 is the subject of a former paper, but the more recent investigation of twin-earthquakes has rendered that account incomplete. I have therefore re-examined the evidence, and, in the earlier part of the present paper, have briefly described the phenomena, in so far as the twin character of the earthquake and its connection with the earthquake of 1904 are concerned.

II. Earthquake of August 4th, 1893.

Time of occurrence, 6.41
P.M.
; intensity, 5; centre of isoseismal 5, in lat. 52° 44·6′ N., long. 1° 13·8′ W. Number of records, 391, from 298 places, and 103 negative records from 97 places (Pl. I).

The curves on the map (Pl. I ) represent isoseismal lines of intensities 5, 4, and 3. Of these, the first is 18 miles long, eleven and a quarter miles wide, and 161 square miles, in area. Its longer axis runs from W. 30° N. to E. 30° S., and its centre is situated at a point 2 miles S. 20° W. of Loughborough. The isoseismal 4 is 46 miles long, 32 miles wide, and contains 1170 square miles. Its longer axis is directed from W. 40° N. to E. 40° S., and its distances from the isoseismal 5 are 8 miles on the
Sarsen-Stones in a Claypit
Authors: Spicer E. C.
Published: October 2009

M
idway
between High Wycombe and Princes Risborough, above Bradenham, 630 feet above sea-level, there is a plateau which is deeply entrenched by transverse valleys running to the Thames, towards which the plateau is inclined in accordance with the dipslope. On riding from Lacey Green to Nap Hill through cultivated country plastered by the usual ‘Clay-with-Flints,’ it appears surprising to find suddenly in the corn-fields a row of brick-kilns in full operation, among heaps of white stones symmetrically cut into kerbstones and paving-setts, with scattered mounds of white débris, pointing clearly to some features of great geological interest.

The principal pit from which these materials are taken exhibits a structure in remarkable contrast with the surrounding country, as will be seen from the accompanying photograph, which shows a large sarsen-block measuring more than 10 feet across, embedded in a fine, clean, tenacious, grey and reddish clay.

On the opposite side of the pit, which is about 40 yards across and roughly circular, another large stone (half uncovered) lies near the surface, and slopes towards the centre of thc pit. In the foreground is seen what the workmen call the ‘rock’, forming a containing-wall for the clay in which the sarsens are embedded. There is no gradation from the ‘rock’ to the fine clay, and the line of demarcation is clear and hard, the large unworn flints in the ‘rock’ never protruding into the sarsen-clay, which free from the admixture of any kind of pebble. It cuts as clean as a
On the Chemical and Mineralogical Evidence as to the Origin of the Dolomites of Southern Tyrol
Authors: Skeats Ernest Willington
Published: October 2009

I. I
ntroduction
.

T
he
country of the ‘Dolomites’ has long been classic ground to geologists. The researches of Dolomieu at the end of the eighteenth century, and of L. von Buch early in the nineteenth, first aroused the interest of geologists in the district. Their attention at first was mainly directed to speculations concerning the mode of origin of the mineral, named after the French geologist, of which the mountains are so largely composed; this question, even at the present day, is far from settled. The stratigraphy of the district has always presented many points of difficulty. The earlier observers, struck by the contrast in scenery and composition between the bold, precipitous, dolomite-masses and the marls and stratified tufts of the green pasture-lands or ‘Alpen,’ were at a loss to explain their mutual relations, especially as very few fossils were at first discovered in any of the deposits. In 1834, however, Graf Münster, who had examined the strata near St. Cassian, enumerated, and (inpart) described and figured 400 species of fossils from them, and subsequent observers have added largely to the number. The precise age of these deposits, which had till then been a matter of discussion, was settled by the examination of their fossil contents. It was shown not only that the beds were of Triassic age, but that, unlike the Trias of most of the European areas, they had been deposited under marine conditions. In 1845 Bronn suggested that the St. Cassian fauna had inhabited a shallow sea where
On Certain Genera and Species of Lytoceratidæ
Authors: Buckman S. S.
Published: October 2009

I. C
ertain
L
ytoceratidæ from the
N
orhthampton
S
ands
(A
alenian
).

S
ome
time ago Mr. Beeby Thompson, F.G.S., sent to me for identification certain species of Lytoeeratidæ from the Northampton Sands. As one is new and remarkable for its homœomorphy to
Phylloceras
, and the others are interesting, I desire to offer the following notes to the Geological Society.

In order to classify the series of Toarcian-Aalenian Lytoceratidæ, to which these species belong (
jurense
and allied groups), it is necessary to note that there is ontogenetic evidence that they have passed through a more or less definite sequence of phylogenetic stages. In regard to ornament, there is a sequence of development—first some elaboration, but, later, simplification from a costate (or corrugate) to a completely-smooth stage. In regard to whorl-shape, there is a constant tendency to pass, more or less in pace with the decline in ornament, from the Lytoceratan to the Phylloceratan form—that is, from an evolute to an involute whorl, the umbilicus constantly contracting. Conjointly with such change there is a further tendency, to pass from stout to coustantly more compressed whorls.

Now,
Lytoceras
originally took its name from the evolute character of its whorls (λυτός);
Phylloceras
from the character of its lobe-line (φύλλον). But the whorl-character of
Phylloceras
is the opposite of λντός: it is involute; and that is what is implied by saying ‘phylloceratan whorl-shape.’ The main difference between the Lytoceratidæ and the Phylloceratidæ may be expressed in this way: the first have the whorl-shape more primitive and the lobe-line
The Tertiary Fossils of Somaliland, as represented in the British Museum (Natural History)
Authors: Newton Richard Bullen
Published: October 2009

I. I
ntroduction
.

S
ince
the publication in the fifty-sixth volume of this Journal (1900) of Prof. J. W. Gregory's paper on the Geology of Somaliland, which was founded upon specimens in the British Museum (Natural History) mostly collected and presented by Mrs. Lort-Phillips, the National Collections have been enriched by two further series of fossils from the same country—that obtained by Dr. Donaldson Smith from the neighbourhood of Berbera, and presented by His Highness the Gaekwar of Baroda; the other presented by Major R. G. Edwards Leckie (of the Canadian Mounted Rifles), and collected by him during an exploration-tour, from Upper Sheikh and Garrasgooi in the Golis-Range district, and also from the Eilo Range of mountains.

In the course of my official duties at the British Museum, I have been entrusted with the examination of these new collections, with the view of describing the individual specimens, as well as of ascertaining their importance with regard to the stratigraphy of the country.

In carrying out this work, a large amount of comparison with species already known from Somaliland and elsewhere has been imperative, while the limestone-matrices surrounding the different specimens have been microscopically examined in several cases, in order that the best confirmatory evidence should be obtained as to geological horizons. This examination has rendered necessary a revision of some of the geological and palæontological conclusions referred to in Prof. Gregory's memoir, for which I am largely responsible in connection with the determination of certain molluscan remains therein mentioned. The new material
The Palæntological Sequence in the Carboniferous Limestone of the Bristol Area
Authors: Vaughan Arthur
Published: October 2009

I. I
ntroduction
.

T
his
paper deals with the fossil sequence in the Carboniferous Limestone of the Bristol area, and with the possibility of dividing that system into a series of palæontological zones.

The general geology of the area has been most luminously expounded by Prof. Lloyd Morgan in the series of papers which he has contributed to the Proceedings of the Bristol Naturalists' Society, and to these I make constant reference. I am thus able largely to dispense with detailed accounts of topography and lithology, which would otherwise interrupt seriously the palæontological discussion.

Mr. E. B. Wethered has contributed a most instructive paper Q.J.G.S. No. 242.

‘On Insoluble Residues obtained from the Carboniferous-Limestone Series at Clifton,’ and it is with his lithological divisions that I have mainly correlated the palæontological zones suggested in this paper.

To the late Mr. W. W. Stoddart we owe the first attempt to compile a list of the fossil contents of the beds in the Avon Section. I have drawn up a complete analysis of his observations, so far only as the Corals and Brachiopods are concerned; this will, for convenience, follow immediately upon the detailed account of my own observations on the Avon section.

For my purpose, it is obvious that the essential desiderata are good exposures, the relative stratigraphical position of which is unquestionable. Exposures which satisfy these two conditions are to be found in several parts of the Bristol area, and, from them, the determination of the faunal sequence is merely a matter
On the Divisions and Correlation of the Upper Portion of the Coal-Measures, with special reference to their Development in the Midland Counties of England
Authors: Kidston Robert
Published: October 2009

W
hile
working out the flora of the British coalfields, I have found no group of rocks more interesting than the group of sandstones and marls, frequently of a red, purple, or mottled colour, and their associated limestones, which lie above the Middle Coal-Measures of the Potteries Coalfield.

When preparing my paper on ‘The Fossil Flora of the Coalfield of the Potteries,’ the classification which I adopted was that used by Mr. John Ward, but at that time little was known about the thickness and stratigraphical relationship of the beds forming this group. The classification adopted by Mr. Ward is as follows:—

In the present paper my remarks will be restricted to the rocks here called Permian and Upper Coal-Measures. Any reference that may be made to the underlying group will be merely incidental.

At the time when my paper on the fossil flora of the Potteries Coalfield was written, I had seen no plants from the so-called ‘Permian’ of that area, and, in regard to these rocks, Mr. John Ward says, in the work already mentioned:—

That these rocks were Carboniferous and not Permian, I felt quite certain: for, apparently, the same so-called ‘Permian’ rocks were passed through while sinking the shaft of the Hamstead Colliery at Great Barr, near Birmingham; they contained a typical Upper Coal-Measure flora; and with this series I classed them at the time. Messrs. F. G. Meachem & H. Insley had previously referred these rocks to the Upper Coal-Measures. I shall have occasion to refer
On the Wash-outs in the Middle Coal-Measures of South Yorkshire
Authors: Middleton Francis Edward
Published: October 2009

D
uring
the past 20 years the South Yorkshire Coalfield has been developed and explored in the neighbourhood of Aldwarke and Thrybergh, lying 4 miles north-west of Rotherham, where the principal seams have been extensively worked, namely:—

The Barnalcy Seam
7½ feet thick.

The Swallow-Wood Seam
5 feet thick.

The Parkgate Seam
4½ feet thick.

As the workings have extended, large areas have been proved to exist where the coal has been removed by wash-outs which have occurred at various horizons in the Middle and Lower Coal-Measures; and it is only by defining these accurately, by survey upon plans, that any intelligent idea can be formed of their origin or probable extension.

On the accompanying plan (fig. 1, p. 339), the position is shown of a wash-out in the Barnsley Seam, which has been proved to exist from Q to R—1700 yards in an east-and-west direction, and by a drift—H to J in a transverse direction.

In the Parkgate Seam, which lies 240 yards below the Barnsley, another wash-out has been proved, covering the area, as shown by the diagonal shading, for a distance of 2600 yards in length in a north-and-south direction, and found to extend 600 yards in width.

The thickness of the strata overlying the wash-out in the Barnsley Seam is 650 yards, and in the Parkgate Seam 500 yards. The position is more clearly defined on reference to fig. 2, section
The Rhætic Rocks of Monmouthshire
Authors: Richardson Linsdall
Published: October 2009

I. I
ntroduction
.

In
Monmouthshire the Rhætic does not extend over a large area, and occurs only in the neighbourhood of Newport. Here it has attracted very little attention until quite recently, when the resurvey of the South-Wales Coalfield necessitated a fresh examination of the deposits, in order to complete the geology of Sheet 249 (New Series). Certain sections which came within the area were described, but hardly in sufficient detail, as the only lamellibranch recorded was
Modiola minima
.

In the present paper four new sections and three new exposures are described: the Goldcliff and Lis-Werry sections being included in the former category, because hitherto comparatively little was known about them.

II. D
ecription of the
S
ections
.

(A) Goldcliff.

About three and a half miles to the south of Llanwern Station, and rising from the alluvial flat called Caldicot Level, is the little inlier of Keuper, Rhætic, and Lower Liassic rocks denominated Goldcliff. Although the occurrence here of Rhætic and Lower Lias has long been known to geologists, details of the section have been difficult to obtain; and, until the present time, it has been possible to investigate only the basement-beds of the Rhætic and those at the base of the Lower Lias. This is due to the fact that the cliff had to be faced with masonry, in order to continue the sea-wall.

About the year 1824 Buckland & Conybeare noted the occurrence here of Lias and Red Marl, but remarked that the section ‘ is now almost entirely concealed by a high sea-wall
The Rhætic and Contiguous Deposits of Glamorganshire
Authors: Richardson Linsdall
Published: October 2009

I. I
ntroduction
.

I
n
the autumn of 1904 I made, in company with my friend, Mr. E. Talbot Paris, a detailed examination of the Rhætic and contiguous deposits of Monmouthshire and GLamorganshire. The results of my investigations in the former country have already been made known, and it now remains to record those in the latter.

Less than four years have elapsed since the officers of the Geological Survey completed the re-survey of the Secondary rocks of Glamorganshire; and that part of the memoir on ‘The South-Wales Coalfield ’ which deals with the Bridgend district was only issued to the public last January. This being the case, it might be thought that but little of interest would have remained to be noticed in the present communication. However, whereas the officers of the Survey were mainly concerned in the mapping of the deposits, my attention was directed ill most cases to the accumulation of facts bearing upon the physical geography of the Rhætic Epoch.

On a previous occasion I communicated to this Society a theory, to account for the geographical distribution in North-West Gloucestershire and Worcestershire of certain beds at the base of the Rhætic Series. I then stated that,

‘there is evidence to suggest that there were earth-pressures at work at the close of the Keuper Epoch, which caused the deposits to be thrown into slight synclinal and anticlinal flexures. In the depressed areas the earlier deposits of the Rhætic were laid down, and successive overlap on to the marls seems
The Causes of Variegation in Keuper Marls and in other Calcareous Rocks
Authors: Moody Gerald Tattersall
Published: October 2009

I
t
has long been known that the colouring of stratified rocks is chiefly due to the presence of compounds of iron, although the conditions under which deposition of iron has taken place have not been fully determined. The occurrence of red and green masses of rock in juxtaposition, such as is observed at the junction of the Tea-Green and Red Marls of the Keuper, has given rise to speculation regarding the origin of variegation, but no hypothesis affording a satisfactory explanation of the chemical changes which must accompany such phemonena has been hitherto advanced.

It is generally taken for granted that the red colour of a variegated rock is determined by the presence of ferric oxide, while the green colour is attributed to iron in the ferrous state; and the suggestion has been made that the condition of the iron in the distinct parts of a variegated rock may, in some cases, be dependent on the relative amount of calcium-carbonate present. As far back as 1868, George Maw called attention to the fact that many noncalcareous rocks are red in colour, and he advanced the opinion that the lighter-coloured bands in variegated rocks have been formed from the red or brown rock by addition of calcareous matter from without. This view, that the green portion has been derived from the red portion, appears to be generally accepted by geologists at the present time; and so it seems desirable to quote at length the concluding paragraph of that section of Maw's
On New Oolitic Strata in Oxfordshire
Authors: Walford Edwin A.
Published: October 2009

T
he
divisions of the Inferior Oolite of North-West Oxfordshire are described, and a quarry on the border of the county cited where the Cotteswold facies dies out in the ‘
Parkinsoni
’-stage. A higher division of the same stage (the
Trigonia-signata
Beds) of Northamptonshire type is shown to sweep over the North-Eastern Cotteswold region. The siliceo-calcareous beds (Chipping-Norton Limestone) cover the countryside which gives them their name, and are about 30 feet thick. Fossiliferous strata, separated from the Chipping-Norton Limestone by a bed with vertical markings and a black clay-band, indicative of much ‘inter-waste’ of these and other beds, are described. They are shown to be similar to the Lincolnshire (Ponton) strata described by Morris, Judd, and Woodward. A new term is proposed for these beds, which are characterized by the presence of the shell
Neœra
, from the
Perna
-Marls above the black clays to a higher series of black-and-green clays underlying the Stonesfield Slate. These beds and the Chipping-Norton Limestones are classed with the sub-Bathonian.

The beds equivalent to those of Oxfordshire have, in Lincolnshire and Northamptonshire, been known in part as Upper Estuarine. In the 20 feet of Oxfordshire strata the 150 feet of the Lincolnshire Limestone and the Upper Estuarine of the north-eastern counties appear to be represented. The Author expresses the hope that his work may help towards the discrimination of the two kinds of deposit known as Lincolnshire Limestones, inasmuch as the fossils characterizing each local (Oxfordshire) stratum have been collected from the beds
in situ
. Lists of fossils are given.
The Carboniferous Limestone of the Weston-super-Mare District (Somerset)
Authors: Sibly Thomas Franklin
Published: October 2009

I. I
ntroduction
.

W
eston-super
-M
are
lies three and a half miles W. 25° S. of Clifton Suspension Bridge. The Carboniferous Limestone in the neighbourhood forms two ridges which stand up prominently from the surrounding alluvial flats. The southern ridge, which I term the Weston-Worle ridge, runs a little north of east from the coast, at Weston, to Worle, and is about 3 miles in length. The northern and smaller ridge, known as Middle Hope (the Woodspring ridge), lies 2 miles farther north, is about 2 miles in length, and runs almost parallel to the Weston-Worle ridge.

The occurrence of contemporaneous igneous rocks associated with the Carboniferous Limestone both at Weston and at Middle Hope, lends especial interest to the district. The igneous rocks have been described by Sir Archibald Geikie and Mr. Aubrey Strahan, and also, more fully, by Prof. C. Lloyd Morgan & Prof. S. H. Reynolds. The Spring-Cove lava (Weston) has, further, been fully described by Prof. W. S. Boulton.

The present paper is devoted chiefly to a detailed description of the Weston-Worle ridge. My object in examining the district was an investigation of the coral- and brachiopod-succession in the Carboniferous Limestone, in connection with my work in the Mendip area, and in continuation of the work accomplished by Dr. Arthur Vaughan in the Bristol area. In order to accomplish this with thoroughness in the Weston-Worle ridge, much detailed stratigraphical work has been necessary, owing to the fact that faulting and resultant folding have complicated the structure of the ridge.

Both the stratigraphy
On the Igneous Rocks occurring between St. David's Head and Strumble Head (Pembrokeshire)
Authors: Elsden James Vincent
Published: October 2009

I. I
ntroduction
.

T
he
area with which this paper deals adjoins the strip of coast lying between St. David's Head and Strumble Head in Pembrokeshire. No detailed account appears to have been given hitherto of the igneous rocks of the greater part of this district, but the Strumble-Head rocks have been described by Mr. F. R. Cowper Reed in his paper on the geology of the Fishguard District. Adjoining parts of the county have also received attention: Mr. John Parkinson has discussed the Prescelly area, and the district south of St. David's, including Skomer Island, has been described by various writers in considerable detail. The granitic rock of St. David's, of classic interest by reason of its disputed igneous origin, has been the subject of exhaustive discussion by Henry Hicks, and has been described petrographically by Thomas Davies, E. B. Tawney, Prof. Bonney, Sir Archibald Geikie, the Rev. J. F. Blake, and Prof. C. Lloyd Morgan. Murchison made some reference to the trap-rocks of Pembrokeshire in his well-known memoir, and these rocks were mapped on the 1-inch scale by the Geological Survey in 1845, under the superintendence of Sir Henry de la Beche, the igneous rocks being re-surveyed in 1855-56 by W. T. Aveline.

Of the stratigraphy of this portion of Pembrokeshire there is still much to learn. Hicks mapped the outcrops between St. David's and Abereiddy Bay, and Mr. Cowper Reed has done the same for the neighbourhood of Fishguard. These lines are approximately shown in the accompanying sketch-map (P1.
Notes on the Geological Aspect of some of the North-Eastern Territories of the Congo Free States
Authors: Preumont Gaston Félix Joseph
Published: October 2009

I. I
ntroduction
.

I
n
1902 I had the honour of being commissioned by the Government of the Congo Free State, as mining-engineer and geologist, to accompany an exploratory mission sent to their north-eastern territories, and I had the opportunity of taking a few notes on the geological aspect of that part of Africa, which is as yet little known to the geologist.

It has occurred to me that the observations recorded during nearly two years spent in that region, although no doubt very incomplete, might possibly be found of some interest.

The Government of the Congo Free State have given me in Africa in a very generous way, through all their officials, every assistance to carry out the investigation of that large tract of country: and I beg to be allowed here to mention my debt of gratitude towards them, as also to thank the Secretary-General of the Interior, Commandant Liebrecht, for the kind permission which he has granted me to bring these notes before this Society.

I am also greatly indebted to Mr. J. Allen Howe, who has kindly undertaken the petrological description of the rocks, for his valuable assistance and advice.

The Uelle district and the Lade Enclave are the north-eastern-most provinces of the Congo Free State. They cover an area at least six times as large as Belgium, and the Uelle district alone extends over 72,000 square miles. On the map it presents the shape of a long and broad belt of country nearly parallel to the Equator,
The Microscopic Structure of Minerals forming Serpentine, and their Relation to its History
Authors: Bonnet T. G. , Raisin Catherine
Published: October 2009

I. I
ntroduction
.

A
lthough
so
much has been written about serpentine during the last thirty years, a few points, as we think, still require to be cleared up. So we propose to describe in this paper, though it will mean some repetition of details already in print, the changes by which that mineral, or group of minerals, is produced from certain magnesian or ferromagnesian silicates. One of us published his first paper on this subject in the beginning of 1877, and since then he has been able to do some field-work on the rock on an average at least once a year. Of the specimens thus procured a number have been sliced for microscopic study, and others acquired by gift or purchase, so that his collection now includes about 180 sections of peridotites and serpentines, besides a large number containing more or less altered single grains of the parent-minerals. From the study of these, and of other specimens in the cabinets of friends, the opinions expressed in this paper have been independently formed, and it would have been written half a dozen years ago, if his arrangements had permitted him to visit certain localities, concerning which, as he believed, incorrect statements had been made. That task was kindly undertaken by the other contributor to this paper, who, in the summer of 1904, supplied the last link by visiting Sprechenstein and the Brenner district. Prior to this she had made a special study of the serpentines of Anglesey and of the Voges,
The Coast-Ledges in the South-West of the Cape Colony
Authors: Schwarz Ernest H. L.
Published: October 2009

The subject of continental ledges has recently been brought into prominence in Europe and America by Prof. Hull, Prof. J.W. Spencer, and others; it is one in which attention to details has revealed many surprising results, which have modified our conception of the relation of land to sea, with the host of cognate problems. I offer the present contribution on the same subject, with the object of further emphasizing the importance of such investigations; for in South Africa we have the same set of phenomena, although we are able to study the movement in quite a different phase from that in which we find it in Europe and along the eastern coast of North America.

The writings of the above-mentioned authors, together with those of Prof. J. Geikie, Prof. A. Issel, and Prof. W. C. Brögger, have made the subject so familiar of recent years, that I need not enter into a discussion of the general principles involved. Suffice it to say that, as the land rises, there are set-backs which allow the wash of the breakers to cut level plateaux of marine denudation ; when a maximum elevation is reached, the land sinks and these ledges or fringing plateaux can be traced in the soundings set down on charts of the coast.In Europe, the first to draw attention to the subject were Godwin-Austen and De la Beche; and since then, the surveys for the submarine cables have furnished the information for a very complete statement of the occurrence in