bluuebunny/crossref_metadata_2025 huggingface dataset:
A Re-excavated Cretaceous Valley on the Mongolian Border
Authors: Brown Barbour George
Published: October 2009

The ancient caravan route across the Mongolian border of China divides for a short distance immediately north of the frontier-town of Kalgan. The Hanoor trail pierces the Great Wall, and enters a ragged gorge, which, for part of its way, follows the line of an old disinterred Cretaceous river-valley. This, after being filled and buried for half the Tertiary Era, was reopened by erosion and used again by rivers in three distinct geological periods, the channel thus becoming a watercourse successively in Mesozoic, Tertiary, Quaternary, and Recent times, and being filled up again, partly or wholly, during each of the intervening epochs. Moreover, the peculiar conditions of preservation of the valley-deposits have made possible the mapping, with considerable certainty, of the early Cretaceous land-surface and the comparison of its configuration with that of the present day.

Examples of buried erosion-surfaces are known in many regions from the basal contacts of continental deposits, as far back as the Torridonian of Scotland. Striking cases have been cited by Watts from Charnwood Forest, by Johnson from the Cerrillos Hills of New Mexico, and by Haughton & Fronmurze from the pre-Dwyka terrane of the Warmbad District of South Africa. In the Kalgan area, however, the clear evidence of the repetition of erosion and deposition at geologically distinct epochs, with the combination of factors which permit the reconstruction of minor details in the original topography, must be almost without parallel, and appears sufficiently unusual to warrant an account of the main features of the occurrence.
The Geological Structure of the Central Mendips
Authors: Welch Francis Brian Awburn
Published: October 2009

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ntroduction
.

The area here termed the Central Mendips comprises that part of the Mendip Hills which lies between Cheddar and Shepton Mallet. This paper deals only with the Palæozoic rocks, which occupy the greater part of the area, and appear in inliers among the Mesozoic rocks on the south.

The eastern, western, and northern boundaries of the area are artificial, the lines cutting across the geological structures.

I wish to express my indebtedness to Dr. Stanley Smith for his unfailing help in the field and laboratory and in the compilation of this paper; to Prof. S. H. Reynolds and Dr. T. F. Sibly for much advice and helpful criticism; to the Department of Scientific and Industrial Research for a maintenance grant; to the Colston Research Society for defraying certain expenses; and, finally, to all others who have in any way helped me.

The area was first surveyed by Sir Henry T. De la Beche, over eighty years ago, and his results were embodied in the 1-inch Geological Survey Map, Sheet XIX, O.S. (1845), as also in the Survey Memoir of 1846 [3]. His account of the structure and stratigraphy is remarkably accurate, and forms the basis of all subsequent work. Except for the publication of William Sanders's geological map in 1862, which was the first large-scale map of the area, no works of importance appeared for more than twenty years after De la Beche's Memoir, until Bristow & Woodward [2] wrote an article dealing with prospects of coal south
The Sequence of Non-Marine Lamellibranchs in the Coal Measures of Nottinghamshire and Derbyshire
Authors: Clift Sydney George , Trueman Arthur Elijah
Published: October 2009

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ntroduction
.

This paper gives an account of the succession of the non-marine Lamellibranchs of the genera
Carbonicola, Anthracomya
, and
Naiadites
in the Coal Measures of the southern portion of the Nottinghamshire, Derbyshire, and Yorkshire Coalfield.

Much collecting was done in the area by Mr. R. D. Vernon (1911), who compiled a valuable account of the non-marine fauna, including lists of the fossils collected at many horizons. Twenty species of Lamellibranchs were recorded, and it was shown that certain of them are somewhat restricted in vertical distribution. Further records were noted by Mr. A. R. Horwood (1912, p. 108). Later, the late Dr. L. Moysey (1913) summarized existing knowledge of the distribution of fossils in the Coal Measures of Nottinghamshire and Derbyshire; a full bibliography of the palæontology of the Coal Measures of the area was compiled by Dr. Moysey, and it is, therefore, unnecessary here to deal fully with the progress of investigation in the area.

In the various memoirs of the Geological Survey dealing with portions of the area, the sequence of coal-seams and the geological structure of the coalfield are fully treated. In most of the memoirs some reference is also made to the non-marine Lamellibranchs and other fossils from the Coal Measures. Dr. Walcot Gibson (1908, pp. 99–102) drew attention to the distribution of such forms as
Carbonicola robusta
and
Anthracomya phillipsii
, and described the fauna associated with the, chief seams in South Derbyshire. Later, these records were extended over a wider area (Gibson, 1913, p.)
The Geology of the Country around Kenilworth, Warwickshire
Authors: Shotton Frederick William
Published: October 2009

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ntroduction
A
nd
P
revious
L
iterature

The area described in this paper extends from Coventry to Warwick, and comprises the Warwickshire quarter-sheets 33 (N.W., N.E., & S.W.), 26 (all four maps), and nearly half of 25 N.E. These have been geologically mapped by myself, while the description also includes sheets 21 S.E. & 21 S.W., and a portion of 20 S.E., areas which were investigated by the officers of the Geological Survey in preparing the map and memoir of the Coventry district [27]. The strip of country dealt with contains, therefore, the southern termination of the barren Upper Coal Measures (Permian of the older maps) which rest on the Productive Middle Coal Measures to the north, and pitch deeper continuously until they are overlaid by Keuper Sandstone. Some inliers of ‘Permian’ south of the main outcrop are also included in the country described. The only maps that previously showed the geology of this area were the Old Series maps LIV N.E. & LIII N.W., surveyed by H. H. Howell & A. C. Ramsay, and first published in 1850. No memoir descriptive of these sheets was written; and only very scanty information is contained in Howell's Memoir of the Warwickshire Coalfield [2], or in Hull's description of the Permian and Triassic Rocks of the Midlands [7]. Occasional papers have appeared describing the scarce fossils found in the ‘Permian’ and Trias of the area, and in this respect the early work of P. B. Brodie [4, 5, 8], G. Lloyd [1], and T.
The Horizons of Bryozoa (Polyzoa) in the Upper Eocene Beds of Hampshire
Authors: Burton Ernest St. John
Published: October 2009

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ntroduction
.

This communication is for the purpose of describing the horizons on which Bryozoa (Polyzoa) occur in the Upper Eocene Beds (marine clays and sands) of Hampshire. No claim is made to establish special zones with particular species confined to them, but those beds are indicated that contain a relative abundance or deficiency of bryozoan remains, within the three broad divisions of the Upper Eocene (Lower, Middle, and Upper Barton Beds).

The geology of this portion of the Hampshire Basin may first be briefly reviewed. The Barton Clay and Barton Sands form part of the well-known Hampshire Syncline, and are exposed at Christchurch Bay, and also at Alum Bay and Whitecliff Bay, in the Isle of Wight. The type-section at Barton Cliffs on the mainland consists of sandy clays in the lower part (50 feet), dark sandy clays and stiff drab clays in the middle part (56 feet), and clayey sands and light-coloured sands in the upper part (96 feet). (Total = 202 feet.)

Corresponding Upper Eocene Beds in the Isle of Wight attain a greater thickness. At Alum Bay, the western end of the island, they reach a total of 338 feet. At Whitecliff Bay, at the eastern end of the island, they reach a total of 368 feet (9, p. 108).

Even these thicknesses may fall short of the maximum totals in the Isle of Wight, owing to the high angle of dip, and to the compression to which so many of the strata have clearly been
The Geology of the District between Llanymawddwy and Llanuwchllyn, Merioneth
Authors: Pugh William John
Published: October 2009

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ntroduction
.

The country described in this paper is situated in South-Eastern Merioneth, but a narrow strip extends over the county boundary into Montgomeryshire. The northern margin is an east-and-west line through Llanuwchllyn, and this is also approximately the southern boundary of the district recently described by Dr. G. L. Elles. The western limit is the high ground made up of Ordovician volcanic rocks: namely, Aran Mawddwy, Aran Benllyn, etc., and the eastern margin is roughly parallel, at a distance of from 4 to 5 miles. The southern boundary is about a mile south of Llanymawddwy, and is adjacent to the Dinas Mawddwy country.

This district occupies an area of about 38 square miles, and is included in the 1-inch Ordnance Survey Map 136, in the Geological Survey Maps, Old Series, Sheets 60 N.W. & 74 S.W., and in the 6-inch maps, Merioneth, Sheets XXIX N.W., N.E., S.W., S.E., XXXIV N.E., S.E., and XXXV N.W., N.E., & S.W.

It is a thinly populated region; Llanymawddwy on the south and Llanuwchllyn on the north are the only villages. Parts of the area are somewhat inaccessible, but the old mountain-road from Dinas Mawddwy to Bala over Bwlch y Groes (1790 feet above sea-level) passes through the district. There is comparatively little ground that can be cultivated, and the area is given over almost entirely to sheep-farming.

The central part of the area is the watershed between three drainage-systems: namely, the Dyfi, the Dee, and the Vyrnwy (a tributary of the Severn). The
The Erratic Rocks and the Age of the Southern Limit of Glaciation in the Oxford District
Authors: Sandford Kenneth Stuart
Published: October 2009

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ntroduction
.

In this paper I propose to study the material of which the Plateau Drift consists in the Oxford District, and to discuss the inferences arising therefrom. For the sake of brevity, and to avoid restating a host of facts already published, it will be assumed that the reader has access to the latest Memoir of the Geological Survey which deals with the district, wherein he will find a detailed account and a full bibliography.

In that Memoir certain problems of the erratic material which abounds in the local superficial deposits had to be left
sub judice
. Research was in progress, aided by the grant from the Daniel-Pidgeon Fund awarded to me in 1924, and I now present the results of the work, expressing gratitude to the Council of the Geological Society for the assistance thus afforded.

I have collected material from the Plateau Drift over a wide area for rather more than eight years, and Prof. W. J. Sollas put at my disposal his important collection, mainly derived from two localities close to Oxford:—Pickett's Heath (on Boars Hill) and Chawley Brickworks, on the flank of Cumnor Hill (Cumnor Hurst).

The considerable mass of material thus available has been reduced to about fifty rocks of essential importance from a petrological point of view, that is, to rocks of character so marked that they can be recognized without fear of grave error.

In the work of recognition, after initial research on my own account, I submitted the material to Mr.
Drifted Plant-Beds of the Upper Estuarine Series of Yorkshire
Authors: Black Maurice
Published: October 2009

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ntroduction
.

The Estuarine Series of Yorkshire consists of non-marine sandstones and shales, which reach a maximum thickness of about 1000 feet. The series is interrupted by three marine bands, all of which may not be present at any given locality. The complete sequence of Middle Jurassic rocks in Yorkshire, as stated by the Geological Survey, is as follows:—

The term ‘Upper Estuarine Series’ appears to have been used for strata in Yorkshire for the first time by Fox-Strangways (1880, p. 3) to designate the strata above the Grey Limestone Series and below the Cornbrash.

Of the marine bands, the Cornbrash and the Grey Limestone Series are by far the most constant, with the result that the Upper Estuarine Series is much the best defined of the three estuarine groups.

The Upper Estuarine Series is exposed in the coast-section from the Wyke (2 miles west of Filey), as far as Ravenscar, where the outcrop turns inland. West of Ravenscar large areas of the moor are formed by outcrops of this series as far as Wheeldale Moor, where a pitch in the Cleveland Anticline brings up lower beds. North of the Esk valley, which cuts down into the Lias, a broad syncline preserves an outlier of the Upper Estuarine Series and the beds immediately above it.

The object of the present paper is to describe and discuss the significance of the variations in the lithology and in the flora of the Upper Estuarine Series, and to show how the nature of
Peterographical Notes On Rocks From The Basal Complex Of Jamaica
Authors: Higham. Frank
Published: October 2009

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ntroduction
.

The notes contained in this appendix are based on the examination of about 120 specimens, which form a part of the collection made by Dr. Matley in the course of his work on the Basal Complex of Jamaica, the majority of the specimens coming from the Kingston district. They have been divided into the same sub-district groups as in the main paper. The other rocks which have been examined are: —first, from a group of andesites and associated instrusives, the position of which in the sequence is, at present, uncertain; and, secondly, a series of pebbles derived from the Complex.

The rocks of the Basal Complex of Jamaica are either igneous, or rocks which have undergone metamorphism. Although they fall into these two groups, the types, especially of the metamorphic rocks, are very varied.

(a) The Igneous Rocks.

Of the plutonic types of igneous rock, which are a part of the Complex, the most important is a granodiorite. Macroscopically, this rock is mesocratic, although some specimens are richer in ferromagnesian minerals than are others. The felspars, when fresh, are colourless; but, when they are slightly altered, the orthoclase assumes a faint pink coloration (K.P. 131). Quartz, a ferromagnesian mineral (usually biotite or hornblende), and sphene can generally be seen in the hand-specimen. A thin section of the granodiorite, examined under the microscope, shows hypidiomorphic crystals of plagioclase (oligoclase-andesine to andesine), which are sometimes poikilitically embedded in orthoclase, or surrounded by allotriomorphic quartz and orthoclase. The dark minerals are
The Geology of the District around Abbey-Cwmhir, Radnorshire
Authors: Roberts Richard Owen
Published: October 2009

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ntroduction
.

The area described in this paper is situated in North-West Radnorshire. The village of Abbey-Cwmhir, which is about 5 miles north-east of Rhayader, is in the centre of the district. The southern boundary is about a mile and a half south of Nantmel, and runs approximately parallel to the main road from Rhayader to Pen-y-bont. The northern and eastern margins are defined by a conspicuous range of hills, which are made up of Wenlock shales and grits; namely, Yr Allt, Cefn Du, Ysgwd Ffordd, and Beddugre Hill, etc. The adjacent ground on the west was described by Dr. Herbert Lap worth in 1900. About 30 square miles have been investigated, and mapped on the scale of 6 inches to the mile. The area is included in the 1-inch Ordnance Survey Maps, Sheets 70 & 80 (coloured edition), and in the Geological Survey Maps, Old Series, Sheets 56 N.W. & N.E.

The district forms part of a dissected plateau, which attains an altitude of about 1500 feet, but Camlo Hill (1670 feet) stands up above the general level of the plateau, and is the highest point in the area. In this plateau, the streams are deeply trenched, and some of the valley-slopes are steep, particularly in the northern part of the region.

The rivers belong to the drainage-system of the Ithon, which joins the Wye about a mile and a quarter south of Newbridge. The principal stream in this district is the Clywedog Brook, with its tributaries (Pandy Brook,
Notes on the Petrography of the Borrowdale Volcanic Series of Kentmere, Westmorland
Authors: Mitchell George Hoole
Published: October 2009

An account of the succession and structure of the Borrowdale Series in the neighbourhood of Kentmere has already been given. In the present communication some additional notes are given on the chemical composition of the rocks and the characters of the flow-brecciation, which is one of the most typical features of the lava-flows. The appearances of certain of the more important characteristics of the rocks when seen in thin section under the microscope are recorded in a number of photomicrographs. The chemical and microscopical work here described was carried out in connexion with the field-work, and the present details are recorded in order to give completeness to an aspect of the subject which was perhaps somewhat neglected in the original paper. It was then felt that the establishment of the structure of the area was the matter of paramount importance. These notes should, however, be read in conjunction with the previous paper, more particularly with reference to pp. 14–30.

It will be seen that the analyses set forth in the accompanying table confirm the descriptions of the lavas given in the previous paper. The Upper Rhyolites are apparently slightly less acid than the Kentmere Pike Rhyolites, while the most acid rocks exposed in the area are the quartz-porphyry intrusions. The differences already described between the andesite-lavas at different horizons are also well brought out in the percentages of silica in the analyses. The variation in the Upper Andesites east and west of the River Kent is especially well seen. Whereas
Fossil Insects of the South Wales Coalfield
Authors: Bolton Herbert
Published: October 2009

I am indebted to the labours of many workers for the opportunity of preparing this paper upon the remains of fossil insects discovered in the Welsh Coal Measures during the last fifteen years.

Some of the specimens are in the National Museum of Wales, having been discovered in the collection of Coal-Measure fossils given to that Institution by Mr. David Davies, of Gilfach Goch.

Dr. A. E. Trueman and Miss E. Dix, M.Sc., have lent insect-remains from the Coal Measures of the Swansea area.

To Dr. F. J. North I am much indebted, not only for the opportunity of retaining specimens for examination over a long period of time, but for information respecting horizons at which the insect-remains occur.

To the Geological Survey and to Mr. John Pringle I am under obligations for the loan of a blattoid wing found by him in shales associated with the Mynyddislwyn Vein at Maes-y-Cwmmer (Glamorgan), and for an Archimylacrid pronotum from the Gwernau Level, three-quarters of a mile south-east of Maes-y-cwmmer, at the same horizon.

The series of wings represents nearly a score of individuals, and constitutes the largest group of Coal-Measure insects yet recorded at one time from any British coalfield. They are, with two exceptions, referable to the Blattoid families Archimylacridsæ, Handlirsch, and the transitional ‘Tribe’ named Heraimylacridia, Pruvost. Only two of the specimens are referable to the most archaic group of fossil insects, the Palæodictyoptera.

As we shall see later, the Hemimylacridian forms now known to occur in the South
Earth-Movements during the Closing Stages of the Neolithic Depression
Authors: Gilbert Charles Jesse
Published: October 2009

Mr. Oldham's interesting paper has a much wider significance than appears upon the surface. I have recently been investigating the phenomena associated with the Neolithic depression in the coastal districts of England, Belgium, and Northern and Western France, and I find evidence of recent earth-movements of striking uniformity. Their sequence, moreover, bears a strong resemblance to those of the Rhôone Estuary; but this, of course, may be fortuitous.

Romney Marsh, in Kent, occupies a large portion of the site of an ancient bay, the shore-line of which ran along the present foothills and around the tributary bays of the river-valleys. Keeping pace with the Neolithic depression, shore-deposits of shingle and sand up to 70 feet in thickness were laid down over the bay. An uplift of at least 25 feet then occurred, and a new shore-line was created some 8 miles to seaward of the former base of the bay. During a considerable halt-stage the Forest of Anderida (which was occupied by Neolithic man) spread out over the enclosed area. The resulting Forest-Bed can be traced in deep drainage-sections in the Marsh and along the western shore-line to Fairlight.

During a subsequent depression a lagoon was formed, in which the alluvium of Romney Marsh and of the river-valleys of the Rother, the Brede, and the Tillingham was deposited; while the new shore-beach was gradually rolled back upon itself for some distance. As a result of this oscillation, about 100 square miles of the ancient bay were reclaimed.

A second uprise
The Glaciation of Clun Forest, Radnor Forest, and some Adjoining Districts
Authors: Dwerryhouse Arthur Richard , Miller Arthur Austin
Published: October 2009

The district described, which comprises the county of Radnor and parts of Montgomeryshire, Shropshire, Brecknockshire, Herefordshire, and Worcestershire, is some 1000 square miles in area, and is included in Sheets 151, 164, 165, 166, 179, 180, 181, 196, 197, and 198 of the 1-inch map of the Ordnance Survey of England & Wales.

To be more precise, the area is bounded on the north by the River Severn from Newtown to below Welshpool; on the east by a line from Welshpool by Forden, Chirbury, and Church Stoke, to Craven Arms and Ludlow, thence by Woofferton and Tenbury to the neighbourhood of Bromyard, and so to Hereford; on the south by tho scarp of the Brecon Beacons and the Black Mountains; and on the west by the River Wye from Builth Wells to its junction with the Ithon, thence along that stream to its head, and so northwards to Newtown.

The country is somewhat complicated topographically, and the drainage-system has been rendered more intricate by the efforts of ice during the glaciation.

The two principal elevated areas within the district are Clun Forest (1666 feet above O.D.) and Radnor Forest (2166 feet O.D.), the former consisting of Ludlow rocks and Old lied Sandstone, and the latter of Wenlock and Ludlow Beds.

South-east of Radnor Forest lies a somewhat faulted belt of country consisting of Silurian rocks, in which the escarpments of the Aymestry and Wenlock limestones are prominent features.

South and east of the Silurian country lies an extensive area of
The Geology of the Country between Nant Peris and Nant Ffrancon, Snowdonia
Authors: Williams David
Published: October 2009

The area here described lies immediately north of the Snowdon ‘massif’, and forms a part of the mountainous tract between the Passes of Llanberis and Nant Ffrancon. Its south-eastern boundary runs from the Ogwen Falls, through Llyn Idwal and Twll Du (Devil's Kitchen) to the upland tarn of Llyn y Cŵn and thence down the Afon Las to the Pass of Llanberis. For the greater part of its length this line approximately coincides with the axis of the Idwal syncline. The northern limit of the area is defined by the top of the Cambrian ‘slate-belt’, between the upper end of Llyn Peris and the northern shoulder of Bronllwyd, near Bethesda.

The area is about 8 square miles in extent, and is represented on the Ordnance Survey 6-inch map, Carnarvon 17 (four quarter-sheets), and on the Geological Survey 1-inch map, 78 S.E. (Old Series).

Owing to the general strike of the stratified rocks, the main ridges and valleys have a north-east to south-west trend. In succession from north to south are the long strike-ridges of Elidir Fach, Elidir Fawr and Carnedd y Filiast, Foel Goch, and Y Garn, all of which rise to over 2500 feet. A long ridge, running northwards from Twll Du to Carnedd y Filiast, crosses the general trend of the area almost at right angles, and forms the watershed between Nant Ffrancon and the Pass of Llanberis. On the east of this divide is a series of eight magnificent hanging cwms which formerly contained tributary glaciers flowing
The Carboniferous Inliers at Codrington and Wick, Gloucestershire
Authors: Smith Stanley
Published: October 2009

On the eastern side of the Bristol coal-basin, south of Chipping Sodbuiy, the Lower Carboniferous rocks are concealed by Mesozoic strata. Near Codrington and in the vicinity of Wick, however, they are exposed as a number of small inliers. These inliers are the subject of the present paper.

The Codrington Inliers are situated 2 miles, the Wick Bocks Inlier 5 miles, and the Grandmother's Rock Inlier, 6½ miles south of the continuous outcrop (see fig. 1, p. 332). The last-mentioned inlier is 14 miles north of the Mendip outcrop. The village of Wick is 7 miles east of Bristol, and the Wick Rocks Inlier, which lies on the north side of the village, occurs on the same line of latitude as the Avon Gorge, some 9 miles away to the west.

The several inliers expose, although not quite completely, a succession of beds ranging from the Tournaisian (Upper
Zaphrentis
Zone) to Coal Measures yielding a Yorkian flora. The upper part of the
Syringothyris
and the base of the
Seminula
Zones are not exposed, and within the ‘Millstone Grit’ a non-sequence undoubtedly occurs.

The arenaceous beds with thin intercalated limestones (D
3
) which succeed the limestone sequence (see table, p. 333) are better exposed in the Wick Rocks Inlier than anywhere else in the Bristol District. Although these beds are well developed on the north-west side of Bristol—at Clifton and Redland, they are no longer accessible there.

Generally speaking, the strata exposed in these inliers have a westward dip, but the actual
The Geological Collection from the South Centeal Sahara
Authors: Rodd. Francis R.
Published: October 2009

As the Central Sahara is geographically one of the least-known areas in Africa, knowledge of its geology is naturally scanty, and all additional information is welcome, especially from its bearing on the relations of the North African and Equatorial seas and on the problem whether the Cretaceous sea of the Sahara and Northern Sudan is a branch of the Tethys, or crossed Africa from the Gulf of Aden to the Niger.

The collection made by Mr. F. R. Rodd, during his journey in 1927, has been sent to us for examination. He has described the geography of the area in the Geographical Journal and also in his book ‘The People of the Veil’. The Massif of Aïr was reported by H. Barth to consist of gneiss, slate, marble, and granite, with flows of basalt and trachyte, and to be flanked by sandstones. Knowledge of the geology of the Aïr Massif and its neighbourhood is due mainly to the work of R. Chudeau, who collected fossils there, and described its geology in his ‘Sahara Soudanais’ and in a series of papers. He discovered Cretaceous limestones with ammonites (1909, 2) and lamellihranchs, which he identified as Turonian; and, on the basis of his work, an extensive area in the Central Sahara has been since regarded as marine Upper Cretaceous and as connected either with the Mediterranean or with the Indian Ocean.

E. Haug, J. W. Gregory, and E. Hennig have represented the Cretaceous of the plains south of Aïr as part of
Ambocœlia Hall and certain Similar British Spiriferidæ
Authors: George Thomas Neville
Published: October 2009

Several small Spirifers of the Upper Palæozoic rocks of this country have been referred to
Ambocœlia
Hall. This genus was proposed to include certain American Devonian and Carboniferous forms with a peculiar internal structure; the genotype, designated by Hall, is
Orthis umbonata
Conrad, a species from the Hamilton Group (Lower Devonian) of North America. In the paper in which he established the genus, Hall (1860, p. 71) suggested that
Spirifer unguiculus
Sowerby sp. (a British Devonian form) might also be included in the genus. The opinion generally held, for example by King (1850, p. 135) and Davidson (1858, vol. ii, pt. 4, p. 59), that
Spirifer unguiculus
is closely allied to, if not identical with,
Spirifer urei
Fleming and
Martinia clannyana
King, led observers to place these species also in the genus
Ambocœlia
. It naturally followed that, so far as the British species were concerned, the genus was described in terms of the external form of these species. In particular, emphasis was laid upon the presence of a dorsal valve considerably flatter than the ventral, and upon the development of a more or less narrowly defined median sulcus in the former. Such a procedure resulted in a neglect of the internal features that Hall so clearly distinguished. Further, the discovery of spines in
Martinia clannyana
, and later in
Spirifer urei
, led to a belief that a spinose surface is also characteristic of the genus. In no instance, so far as I am aware, has any reference been made to the
The Tuedian Beds of Northern Cumberland and Roxburghshire East of the Liddel Water
Authors: Garwood Edmund Johnston
Published: October 2009

The object of this communication is to describe an interesting lagoon phase which occurs in the Tuedian Beds of Northern Cumberland and the neighbouring Border country in Roxburghshire, a feature of special interest being the development of algal limestones in the Cementstone Series.

The area dealt with is included in the sketch-map (fig. 1) and comprises

1.

The Northern Cumberland district drained by the River Lyne and its tributaries between the River Irthing and the Liddel Water.

2.

The part of Roxburghshire lying between the Liddel Water and the English Border.

3.

The western part of Mid-Northumberland south of the Cheviot.

The Northern Cumberland district is included in the Geological Survey 1-inch map of England and Wales, Sheet No. 106 N.W. (old series), while the Roxburghshire district is contained in the Scottish 1-inch map, Sheets Nos. 11 and 17. No memoirs have been published for any of these sheets. Three of the sections, however, which accompany the memoir on the Canonbie Coalfield by B. N. Peach and J. Horne traverse some of those parts of Roxburghshire dealt with here, and the authors give a list of fossils collected from this district during the progress of their survey.

The fullest development of the Tuedian Beds is found in the Cumberland portion of the area, and the succession there will be described in detail. Interesting sections also occur in the Scottish tract east of the Liddel Water, and an account of this area
The Flora of the Upper Portion of the Coal Measures of North Staffordshire
Authors: Dix Emily
Published: October 2009

The stratigraphy of the Coal Measures of North Staffordshire is, perhaps, better known than that of any other coalfield in this country. This is undoubtedly due to the detailed work carried out by pioneer workers such as Wheelton Hind, John Ward and Mr. J. T. Stobbs, and also to the fact that this coalfield offers remarkable facilities for the study of the various horizons in the Coal Measure sequence. The upper portion of the Middle Coal Measures and the lower part of the Upper Coal Measures, in particular, are (owing to the economic value of the pottery clays and the Black Band Ironstones) admirably exposed in quarries and excavations. These sections give an almost complete succession from the Ash Coal to the Keele Series.

The present paper deals with the distribution of plants in the Coal Measures above the horizon of the Ash Coal. Most of the species here recorded were collected in the course of investigations chiefly concerned with the non-marine lamellibranchs in those measures, and undertaken while I was acting as research assistant to Prof. A. E. Trueman. A grant in aid of this work was received from the Department of Scientific and Industrial Research.

I desire to acknowledge the assistance which has been given by all owners and officials of mines and marl pits in North Staffordshire. They not only allowed access to sections, but also gave facilities for collecting both above and below ground. As a result, the original records given in this paper refer to
A Classification of some Rhyolites, Trachytes, and Phonolites from part of Kenya Colony, with a Note on some Associated Basaltic Rocks
Authors: Smith Walter Campbell
Published: October 2009

In spite of the importance of the volcanic region of the Great Rift Valley of East Africa, very little attention has been paid in the past to the detailed petrography of the rocks of Kenya Colony.

Previous work on the subject may be summarized in a few sentences. August Rosiwal described the rocks collected by L. von Hohnel on Count Teleki's expedition in 1886–88 (1891, pp. 490–511).

Descriptions of some of the lavas of Mount Kenya were given by J. W. Gregory (1900) in his account of the geology of that mountain, which he ascended in 1893, and G. T. Prior (1903) described the rocks collected by Gregory in other parts of the Colony on the same expedition, and specimens from a collection presented to the British Museum (Natural History) by Sir H. H. Johnston in 1901. This paper contained five analyses. H. B. Maufe (1908) gave an account of the field relations of the rocks which he collected in 1905 and 1906 along the line of the Uganda Railway and on several traverses from various points along it. He followed Prior's nomenclature fairly closely. A few specimens collected by G. Uhlig, also on the line of the Uganda Railway, were described by M. Goldschlag (1912), who gave four analyses. Miss A. T. Neilson (1921) gave a brief description of the rocks collected by J. W. Gregory in 1919. Finally, A. Lacroix (1923) gave a short summary of the work of these earlier authors and added four new analyses of
The Glaciation of Western Edenside and Adjoining Areas and the Drumlins of Edenside and the Solway Basin
Authors: Hollingworth Sydney Ewart
Published: October 2009

This paper is divisible naturally into two parts. The first deals with the glaciation and deglaciation of western Edenside and adjoining areas, including the eastern and north-eastern parts of the Lake District as far north-west as Skiddaw. The work, which was commenced in 1923 as the result of problems which arose during the re-survey of the Brampton Geological Survey Sheet, has been facilitated by the fact that throughout I was in constant touch with Dr. F. M. Trotter, who was investigating the area east of the River Eden at the same time.

At an early stage in the work it was found that the drumlins were parallel to the ice-fronts for considerable distances. This was entirely unexpected and led to the study of the drumlins of a much larger area; this study forms the subject of Part II. Its results are of more than local interest, and this, together with the difference in area dealt with and the complexity of the problem, justifies, it is hoped, its separation from the chronological sequence in Part I. The drumlins mapped by my colleagues, Messrs. E. E. L. Dixon, J. M. Maden, L. H. Tonks, and F. M. Trotter, in the Carlisle Sheet, and by Mr. T. Eastwood in parts of the Bewcastle and Cockermouth Sheets, together with a larger area east of the Eden mapped by Dr. Trotter, have been incorporated in Part II. To these investigators my thanks are due for permission to utilize the result of their mapping; for its
The Post-Glacial Deposits of the Lincolnshire Coast
Authors: Swinnerton Henry Hurd
Published: October 2009

Between the Lincolnshire Wolds and the coast there lies a narrow belt of low-lying land usually referred to as the Lincolnshire marsh. Within this belt two types of scenery exist. The one, founded on boulder-clay, is characterized by a well-wooded hummocky surface. It occupies a continuous strip of country along the foot of the wolds (Pl. XXX), but its seaward margin is irregularly indented and has outlying patches standing up like large mounds in the marshland proper. The latter constitutes the second type of country. It is flat and almost treeless, and is made up of stiff clays mainly of estuarine origin. The process of building up this marshland is still going on along the coast north of Mablethorpe and south of Skegness. The first-mentioned portion of the coast lies under the lee of Spurn Point, the latter lies within the shelter of the Wash, where extensive salt marshes exist.

Between Mablethorpe and Skegness the coast is being slowly eroded. This fact is disguised by the absence of cliffs and the presence of an almost continuous covering of sand which hides the outcrops of the marshland clays. Owing to the action of the waves and currents, this sheet of sand as it drifts southwards becomes broken by valley-like hollows, often more than a mile long, which extend obliquely across the beach. These hollows are scoured by strong and dangerous currents which sweep away the sand and both expose and erode the clays beneath. They offer the only natural and, at
Land-Bridges across the Atlantic and Pacific Oceans during the Kainozoic Era
Authors: von Ihering Hermann
Published: October 2009

My research work on the history of South America, its formation from several distinct land-masses and its relationship to other continents, pursued continuously since 1890, reached some degree of finality in my book on the Atlantic Ocean. As the results of these researches had not for many years received any recognition by geologists, it was particularly pleasing to me to find that in his presidential address on the same subject Prof. J. W. Gregory has expressed opinions which for the most part coincide with mine. In this most interesting account of his researches he brings together an astonishing number of facts, and in so doing arrives at the conclusion that until Miocene times the Atlantic Ocean was still spanned by an African-American land-bridge. This agrees with my conception of the conditions then prevailing, according to which the Upper Miocene beds of Entre Rios are the first in which marine mollusca, echinoderma, and selachia, derived from the northern and southern seas, mingle. Gregory, as well as C. Schuchert, rejects on geological grounds the drift theory of Wegener and A. L. Du Toit, as do all German geologists with whom I have been in contact. Wegener's hypothesis, so far as it relates to the Atlantic shores of Africa and South America, demands the permanence of the present form of these continents as far back as the Cretaceous epoch. Against this idea it must be noted that geology has never admitted the persistence of a long stretch of coast-line, 50 to 60 degrees
Jointing in the Great Scar Limestone of Craven and Its Relation to the Tectonics of the Area
Authors: Wager Lawrence Rickard
Published: October 2009

The Great Scar Limestone of Kilnsey Moor, 4 miles northwest of Grassington in Wharfedale, is traversed by many approximately parallel lead-veins whose direction is marked, in the field, by a series of small trial holes for lead. Over the same area, the limestone is cut by two series of joints which are nearly at right angles to each other. One of these sets of joints is parallel to the lead-veins. Traced towards the North Craven Fault, near Skirethorns, both the lead-veins and the joints parallel to them are found to change from a north-east and south-west direction to an east-north-east and west-south-west direction.

These observations, which were made in 1926, were sufficient to suggest:

(1)

that the jointing was probably formed in pre-Permian times, as the joints may be occupied by lead-veins for whose pre-Permian age there is considerable evidence;

(2)

that the jointing was produced by regional stresses, since it is constant in direction over large areas;

(3)

that the jointing, since it alters its direction on approaching the North Craven Fault, may be connected in some way with the faulting and may, therefore, throw some light on the nature of the Craven Fault-system.

To test these tentative deductions, and, if possible, to decide the relations between the joints and the tectonics of Craven, a detailed map of the direction of the jointing in the horizontally-bedded Great Scar Limestone between Dentdale, Wensleydale, and the Craven Faults was begun.

Previous
On the Genotype and Septal Development of the Coral Genus
Petraia
Münster
Authors: Schindewolf Otto H.
Published: October 2009

No genus of Palaeozoic coral has been so repeatedly misinterpreted as
Petraia
, and certainly no name has been so often misapplied. The genus was founded by Count G. zu Münster in 1839 (p. 42) for certain fossils from the Orthoceratites Limestones of Elbersreuth and the Clymenia Limestone of the Schübelhammer in the Frankenwald (Bavaria), and placed by him among the gastropoda, near
Capulus
and
Patella
, though doubtfully, for he also thought that they might possibly be zoophytes and related to ‘
Cyathophyllum
’. Nevertheless, in 1840 (pp. 82 & 116), he claimed them to be most probably gastropods. On the other hand, W. Lonsdale (1840, explanation of pl. lviii, fig. 6), having seen some of Münster's specimens, recognized
Petraia
as a coral, an opinion upheld by A. d'Archiac & E. de Verneuil (1842, p. 405), J. Morris (1843, p. 42), H. B. Geinitz (1846, p. 566), H. G. Bronn (1848, p. 949), and F. M'Coy (1849, p. 1).

Münster's description, however, was very vague, and no reference was made to the septa; nor were the internal characters of the types known. So it has come about that the name
Petraia
has been applied by later writers to various Palaeozoic corals ranging from Ordovician to Permian. Because of this confusion, A. d'Orbigny (1850, p. 105), H. M. Edwards & J. Haime (1851, p. 392), F. J. Pictet (1857, p. 455), E. de Fromentel (1858–61, p. 294), and others have entirely dropped the name
Petraia
and included the species it embraced in the very
The Geological Work of the Cambridge Expedition to East Greenland in 1929
Authors: Parkinson Mark Mervyn Leofric , Whittard Walter Frederick
Published: October 2009

East Greenland, a country of high coastal mountains receding under the cap-ice and of great fjords bounded by towering cliffs, has, within the last decade, attracted once again the attention of investigators. After an unsuccessful attempt in 1923, Mr. J. M. Wordie succeeded in reaching land and exploring Gael Hamkes Bay and Franz Josef Fjord in the very favourable ice year of 1926 (Wordie, 1927). That same summer, Dr. Lauge Koch took a party to Scoresby Sound, and himself made a sledge-journey the next spring northwards to Germania Land, returning by way of the fjords (Koch, 1929). Since Dr. Koch wished to elucidate further the stratigraphy of the Palæozoic rocks in 1929, the third Cambridge Expedition of 1929 concentrated mainly upon a determination of certain tectonic problems in the pre-Old Red Sandstone rocks, and upon a journey inland from Kjerulf Fjord into unknown country (Wordie, 1930). Had time permitted, a party was to sledge from the head of Gael Hamkes Bay as far north as Queen Louise Land, in order to determine the relations existing there between the sedimentary and metamorphic outcrops; but owing to delay in the pack-ice, this plan had to be abandoned.

The large fjords, Franz Josef Fjord and King Oscar Fjord, are connected through Antarctic Sound, and measure respectively about 110 miles and 45 miles in length. They have many branches, most of which traverse the rock-sequences across the dip, and afford cliff-sections of multicoloured bare rock, often attaining 6000 feet in height. The fjord-system is
The Loch Doon ‘Granite’ Area, Galloway
Authors: Gardiner Charles Irving , Reynolds Sidney Hugh
Published: October 2009

I. I
introduction

F
our
large and several small plutonic masses occur intrusive in the Lower Palaeozoic rocks of the south-west of Scotland, the four large masses being those of the Criffel, the Cairnsmore Q.J.G.S. No. 349B of Fleet, the Loch Doon area, and the Cairnsmore of Cars-phairn. It is the object of the present paper to describe the Loch Doon mass, the intrusions which surround it, and its metamorphic aureole.

The Loch Doon mass is intrusive into Ordovician sediments showing the prevalent north-east to south-west strike which was imparted to the rocks of much of the south and west of Scotland by the Caledonian movements. These rocks include Hartfell and Glenkiln beds, represented by grits, flags, and black graptolitic shales, and Arenig beds, which include grits and radiolarian cherts. The district is included in Sheet 8 of the 1-inch Geological Survey map of Scotland.

The plutonic rocks occupy a large area extending for a distance of 11½ miles from Loch Doon in the north to just south of Loch Dee in the south, and spread over about 47 square miles. The outcrop is somewhat hour-glass shaped with a maximum width of 6½ miles, and the plutonic rocks are almost everywhere surrounded by high hills composed of metamorphosed Ordovician sediments, which form the Kells Range on the east and the Merrick Range on the west. Both ranges are, for the most part, well over 2000 feet high, Corserine in the Kells Range rising to 2668 feet and Merrick to 2764 feet. Through
The Glacier-Lakes of Eskdale, Miterdale, and Wasdale, Cumberland; and the retreat of the Ice during the Main Glaciation
Authors: Smith Bernard
Published: October 2009

I. I
ntroduction

T
he
occurrence in former times of glacier-lakes in this country, due to the impounding of drainage from a locally-glaciated mountain group by an impinging ice-sheet, is nowadays accepted as an undeniable fact, and the discovery of one or more fresh cases would not in itself excite much interest or justify more than a brief notice. The lakes, however, which are the subject of this communication, take their place in a larger story, and furnish links in a chain of evidence leading to definite conclusions about the mode of withdrawal of the great Irish Sea ice-sheet from the Cumberland and North Lancashire coastline towards the close of one great episode in the glacial history of the north of England. Their deposits, also, exhibit features of a somewhat novel type. Enough details, it is hoped, will be presented to establish the existence, situation, and place in the sequence, of the former glacier-lakes in Eskdale, Miterdale, and Wasdale.

In the past, brief references have been made to the glaciation of this district by D. Mackintosh (1871, 1872, 1879), J. Clifton Ward (1875), C. E. de Ranee (1871 [I & II]), and the late J. D. Kendall (1879-80, 1881-82); but it was left to T. Mellard Reade (1893), in his description of the Eskdale drift, to discuss the local glacial geology in particular detail. Although his conclusion cannot be accepted that all the drifts up to at least 400 feet above sea-level are marine, his observations are of great value and interest.
A Contribution to the Petrology of the Metamorphic Rocks of East Greenland
Authors: Dugdale Holt Wiseman John
Published: October 2009

I. I
introduction

T
he
main object of the present paper is a petrological description and a consideration of the genesis of the metamorphic rocks collected by the Cambridge 1926 and 1929 East Greenland Expeditions.
1
The Danish Expedition of 1926-27, under the leadership of Lauge Koch, paid no special attention to the metamorphic rocks,.
2
but a preliminary report of the Danish Expedition of 1929 making good this omission has recently been published.
3
In this report Backlund states that the gneisses of the inner fjord region ‘were formed by mag·matization and syntexis of exceedingly varying sediments by a younger (Caledonian) granite’ (p. 236). He considers, therefore, that most of the metamorphic rocks originated through the assimilation of the Franz Josef Beds by Caledonian granites. It is the aim of this paper to study these ancient gneisses and schists in thin section, in the hope that a better understanding may be obtained both of their metamorphic condition and of their ætiological relations.

II. T
he
W
estern
M
etamobphic
C
omplex

A kyanite-garnet-gneiss was collected from the median moraine of the Nordenskiöld Glacier. Under the microscope, this gneiss is a coarse-grained rock with porphyroblastic crystals of garnet and kyanite. Generally, the garnets exhibit their shape, and are characterized, by an outer rim almost free from inclusions, and an interior region rich in inclusions, especially of quartz, rutile, biotite, tourmaline, and magnetite. The garnets are traversed by two systems of partings, approximately at right angles one to the other. In some individuals the kyanite has been twinned on the