bluuebunny/crossref_metadata_2025 huggingface dataset:
An Outline of the Geology of South-Western Lleyn
Authors: Matley C. A.
Published: May 2009

A geological survey of the Pre-Cambrian area of South-Western Lleyn and of some of the Ordovician country to the east of it was made by the present writer between the years 1909 and 1912. An account of the geology of Bardsey Island was published in 1913, but ten years' absence abroad has delayed the description of the rocks of the adjacent mainland. A further absence from Europe will cause additional delay in the presentment of a full account of the district, and it seems desirable that some of the more important results of the survey of this tract of ground should now be placed on record.
A Mid-Avonian Reef Limestone and Conglomerate in the Craven Lowlands
Authors: Hudson R. G. S.
Published: May 2009

The Lower Carboniferous rocks of the Craven Lowlands are predominantly fine-grained dark argillaceous limestones and calcareous mudstones and shales with a fauna of Zaphrentid or Caninoid phase. At various horizons and along various belts these argillaceous rocks are replaced by reef limestones and the associated crinoidal limestones, reef sands, and “calcaire grumeleux”. These lisnestones usually contain a specialized reef fauna or more rarely the standard coral-brachiopod fauna.
The Use of Graphs in Palaeontology
Authors: Swinnerton H. H.
Published: May 2009

Graphic methods for the comparative study of numerous observations and facts have long been in use in the exact sciences. They have also been used to some extent in those branches of the descriptive sciences which deal more particularly with the problems of heredity and variation. The purpose of the present paper is to sketch in outline a way in which they may be used in the morphological and systematic study of fossils.
The Wackerfield Dyke, County Durham
Authors: Holmes Arthur , Smith Stanley
Published: May 2009

The dyke to be described in this paper has not hitherto been noticed in petrological literature, although the western part has been recorded on the map of the area by the Geological Survey. It exhibits, nevertheless, some interesting features and adds data to our knowledge of the minor intrusions of north-east England.
The Foraminifera of the Hartwell Clay and Subjacent Beds
Authors: Neaverson E.
Published: May 2009

1. Thirty-six species of Foraminifera are recorded from various localities in the Hartwell Clay and associated beds.
2. The assemblage of species is characterized by:—
(a) the abundance of rotulate Cristellarians of Lower Cretaceous type, and of Cristellaria fragraria.
(b) the common occurrence of Vaginulina harpa, a Jurassic type.
(c) the rarity of arenaceous, and the absence of porcellanous forms.
3. The Foraminifera from the Hartwell Clay are compared with those from other deposits in the Aylesbury district, and with those from foreign deposits of similar age.
4. The relative abundance of glauconite is a point of similarity between the Hartwell Clay and beds hitherto regarded as Kimmeridge Clay.
On a Local Alteration in Limestone Shales at Wensley, Derbyshire
Authors: Garnett C. S.
Published: May 2009

A Small stream forms the boundary between the Parishes of Wensley and Winster, on the north-west of the former; and here abouts its bed, in the Limestone Shalc; is probably about 30 feet above the Carboniferous limestone. On the Winster side, the shales form a oded slope (Whites Wood) rising 100 feet in about 200 feet, and on this side the shale is quite normal and of the black colour usual in the lower beds of this formation. On the Wensley side the ground rises more gradually, and the actual bank of the stream averages not more than about 10 feet in height. Here, an altered shale is exposed and can be traced (through the activity of moles) in the fields behind.
Fossils from Western Persia
Authors: Currie Ethel D.
Published: May 2009

A Collection of fossils from the area of Pusht-i-Kuh, on the western border of Persia, has been forwarded recently to Glasgow University by Dr. W. R. Smellie.
Further Studies in Chert. I
Authors: Sargent H. C.
Published: May 2009

Dr. F. W. Clarke truly observes in regard to the origin of chert: “No one process can account for all the occurrences of amorphous and cryptocrystalline silica, and each locality must be studied in the light of its own evidence.” (Data of Geochemistry, 1916, p. 544.)
Note on a Specimen of Micraster showing Unusual Features
Authors: Silvester Norman L.
Published: May 2009

The specimen to be described was disinterred by the writer in a small and practically disused Chalk pit on the east side of the road leading from Sulham village (Berkshire) in a S.S.E. direction towards Theale, and 530 yards distant from the former. The place of burial was in the undisturbed face of the pit at about 5 feet above the road level of 190 feet above sea-level. The exposure is recorded on the 6 inch map sheet XXXVI surveyed by J. H. Blake in 1895. The Chalk in which the pit occurs is coloured as “Upper”, but the precise zone is not indicated either on the map or in the memoir (1).
A Preliminary Note on the Glaciation of Borrowdale, Cumberland
Authors: Raistrick A.
Published: May 2009

During an extended study of the glacial phenomena of the above area, which includes the drainage of the Rivers Derwent and Greta, and the drainage basin of Bassenthwaite Lake, several features of general interest were found which it is proposed to outline here.
On Some Specimens of Fossiliferous Sandstone from Pahang, Malay Peninsula
Authors: Weir John
Published: May 2009

In 1900 Mr. R. Bullen Newton described the casts and impressions of some lamellibranch shells, in blocks of fossiliferous sandstone from Kuala Lipis, Pahang.1 On account of the prevalence of specimens which he assigned to the genus Myophoria, Mr. Newton called the rock “Myophorian Sandstone”. Amongst other species identified by Mr. Newton Chlamys valoniensis has a wide distribution, “and is characteristic of the Ehaetic or uppermost Trias. It is to this horizon, therefore, that the Myophorian Sandstone must be referred”.
On the Geology of Castle-an-Dinas Wolfram Mine
Authors: Davison E. H.
Published: May 2009

THERE are two hills named Castle-an-Dinas in West Cornwall, one near Penzance and the one on which the Wolfram Mine is situated, which lies about 2 miles east of St. Columb Major and about 4 miles to the north of the St. Austell granite mass.
Morphological Studies on the Echinoidea Holectypoida and their Allies
Authors: Hawkins Herbert L.
Published: May 2009

WHILE collating the plates in a recently acquired copy of the Revision of the Echini (A. Agassiz, 1872–4), I noticed with surprise a representation of complex ambulacral structure in “Echinobrissus” recens (pl. xiv a, figs. 3–4). A style of plate-grouping essentially similar to that in Echinonëus (tab. cit., figs. 7–8) is portrayed as affecting all the extra-petaloid parts of the five areas, and encroaching slightly on the distal parts of the petals. No reference to this unusual condition occurs in the text. As the proofs of my recent paper on ambulacral structures (Phil. Trans., B, vol. 209) were in my hands at the time, I was immediately impressed by the remarkable resemblance between “E.” recens and the Cretaceous Trematopygus—a correspondence by no means restricted to ambulacral plating, but involving all coronal features save the orientation of the peristome.
On the Investigation of the Mechanical Constitution of Loose Arenaceous Sediments by the method of Elutriation, with special reference to the Thanet Beds of the Southern Side of the London Basin
Authors: Baker Herbert Arthur
Published: May 2009

THE speeds of the currents employed in the elutriation process in sorting diversely sized material bear no relation whatever to the speeds of the currents, which are competent to transport the same material. The elutriation process in no way imitates the natural processes whereby sediments are transported, sorted, and deposited. The determination of competent velocities in relation to size of material transported is quite a distinct investigation, and one which still calls for much study in spite of the time and attention given to it by numerous workers.
The Metamorphism of the Pre-Cambrian Dolomites of Southern Eyre Peninsula, South Australia
Authors: Tilley C. E.
Published: May 2009

THE rocks arising from the metamorphism of the more impure dolomitic sediments are calc-magnesian silicate types in which all carbon dioxide has been expelled. In some of the rocks to be described it is clear that superposed on the normal metamorphism there has been a metamorphism by addition of material from the neighbouring magma.
Notes on the Family Encrinuridae
Authors: Reed F. R. Cowper
Published: May 2009

It has generally been held that the family Encrinuridae contains the four genera Encrinurus, Cybele, Cromus, and Dindymene, though Cromus is sometimes regarded as only a sub-genus of Encrinurus. The distinctive features of Encrinurus and Cybele as usually understood have been described and discussed by many authors, especially Salter, Nieszkowski, and Schmidt, but in 1877, Woodward considered Cybele to be only a sub-genus of Encrinurus. Dindymene is sufficiently distinct from the others to have had generic rank always accorded to it.
Origin of the Relict Fauna of Lough Neagh
Authors: Charlesworth J. Kaye
Published: May 2009

Lough neagh is one of the numerous lakes possessing a few species, either identical with or differing but slightly from true marine forms living in the present seas. The idiots of Lough Neagh are the pollan, Coregonus pollan, and the shrimp, Mysis relicta (a near relative of the marine Mysis oculata). They have been described by Dr. R., F. Scharff and Professor W. Dakin and Miss M. Latarchie.
Odontocaulis Lapworth, a synonym of Callograptus Hall
Authors: Bulman O. M. B.
Published: May 2009

The original generic diagnosis is as follows:—

“Polypary cyathiform, composed of numerous independent and frequently bifurcating polypiferous branches, originating from the distal extremity of a short stem, which is likewise polypiferous and is terminated proximally in an irregular corneous expansion. Hydrothecae of the type of those of Dictyonema, biserial, sub-alternate.

“The chief peculiarity of this genus is afforded by the character of the stem, which is identical in every respect with the main branches, and, like them, is denticulate or polypiferous throughout the whole of its extent. It commences proximally in a flattened expansion, with irregular or frayed-out edges, possibly the remains of a disk or bulb of attachment.

“The mode of branching is rigidly dichotomous, the first two branches being formed by the sub-division of the main stem itself. Each arm branches and rebranches again and again in the same manner, at frequent and close intervals, composing an elegant cyathiform or fan-like polypary, very symmetrical in form. The branches retain their original width to their final division, which gives rise to two minute branches less than one-tenth of an inch in length.
Chert Deposits in Ecuador, South America
Authors: Sheppard George
Published: May 2009

The following notes have been recorded with the idea of showing that a field relationship exists between true chert veins or aggregations, and certain igneous intrusions. Beyond the fact that the cherts have been formed probably as the result of some hydrothermal agency, usually associated with, and occasionally the result of, volcanic episodes, it is not possible to enter more fully into the geological origin of this form of silica. Microscopic fossils have been observed and recorded from the cherts of Santa Elena, but the presence of these organisms may be accounted for by the fact that certain Radiolaria are able to exist in waters of a fairly high temperature, it is also possible that these fossils may have been abstracted from the vein walls of the country rock during the secondary process of infilling by crypto-crystalline silica.
A Shelly Band in Graptolitic Shales
Authors: Challinor John
Published: May 2009

In the midst of a typically graptolitic development of the Valentian Series in Wales, a thin band containing a variety of shelly fossils has recently been noticed. It occurs in the Rheidol Gorge, Cardiganshire; part of the region described by Professor O. T. Jones in 1909 (1); the locality being that referred to by him as “F. 15”, and the stratigraphical position 6 feet below the layer of calcareous nodules defining the top of the “Triangulatus-var.-band”; the shale band “2” in the table showing the beds of the zone of Monograptus communis as developed in the Rheidol Gorge (1, p.488). Professor Jones refers to the presence of “fragments of Orthoceras or Conularia” at this locality. The band has an available outcrop of about 10 feet in length, and it was possible to examine it for some 2 or 3 feet in the direction of dip. It is about 3 inches thick and is not individualized in any way other than by its fossil contents; lithologically it is to all appearances the same as the rest of the dark-blue iron-stained shales in which it occurs.
The Terms “Cast” and “Mould” in Palaeontology
Authors: Challinor John
Published: May 2009

In preparing a course of lectures in elementary Palaeontology, the present writer found himself to be vague as to the general terminology of the most elementary part of his subject—the forms of preservation in which fossils occur. To his surprise he found, on referring to the leading text-books, that there was no such general terminology; at least, not in the sense of a terminology in general use.
The Alston Block
Authors: Trotter F. M. , Hollingworth S. E.
Published: May 2009

The area covered by this paper embraces the northern end of the Pennines—the uplands of Lower Carboniferous rocks centred about Alston, together with the low ground of the Tyne-Irthing gap to the north. It is bounded on the west by the Vale of Eden. The Pennine portion is separated structurally from the regions to the north and west by the Stublick and Pennine Faults respectively. The former trends E.N.E., it has a downthrow to the north and has resulted in the preservation of the string of Coal Measures outliers which form a connecting link between the Cumberland and Northumberland coalfields. The Pennine Fault, trending S.S.E., with a throw of several thousand feet to the west, brings the New Red rocks of the Vale of Eden against the Lower Carboniferous beds of the Pennine Escarpment. These two faults meet at right angles near Castle Carrock. To the south the Pennine Fault dies out near Stainmore, and another dislocation, the Dent Fault, trending S.S.W., develops, and eventually links up with the Craven Faults which have an E.S.E. trend. These four faults, as pointed out by Professor Kendall, have the form of a reversed 3, and the region within this figure has become known generally as the Northumbrian Fault Block. Professor Marr has aptly termed the southern half of this area the “Rigid Block”. The northern half of the Northumbrian Fault Block, which will be shown to possess many characters in common with the southern half, is here called the “Aiston Block”. Its limits are defined on three sides—by the Stublick Fault on the north, the Pennine Fault on the west, and by the Stainmore depression on the south. The last thus divides the Northumbrian Fault Block into two, physiographically and structurally. The eastern boundary of the Alston Block is concealed beneath the Mesozoic rocks.
The Silica Lines of British Honduras
Authors: Ower Leslie H.
Published: May 2009

British Honduras may be briefly described as a 3,000 feet peneplain of upper Carboniferous slates, surrounded by thick dense Oligoceue and Miocene limestones. The slates have a strike of about 250° conforming to the general Central American trend, produced at the close of the Palaeozoic. Granodiorite and quartz-porphyry were intruded at this period. The newer formations with their extension through Yucatan into Western Cuba, curve from north to north-east parallel to the rim of the 2,500 fathom Yucatan basin.
Studies in the Variation ofBatillaria pleurotomoides(Lam.)
Authors: Rowlands T. Hudson
Published: May 2009

Recently Mr. A. Stuart (1927, PP. 545–57) has published an account of the variation in a large number of specimens ofVolutospina spinosafrom the Calcaire Grossier of Grignon. In his study of that group he emphasized the variation in the ontogeny of the individual, and suggested the importance of such studies in relation to the more philosophical aspects of biology and in relation to the application of ontogenetic evidence to the problem of classification. The group studied by Mr. Stuart was one in which the latitude of variation in any character was particularly small.
Metamorphism in the Upper Devonian of N. Cornwall
Authors: Phillips F. Coles
Published: May 2009

The geological succession and structure of the district are briefly summarized. Evidence of stress conditions becomes increasingly abundant as one passes from south to north towards the boundary of the Carboniferous.

The thermal alteration due to the Bodmin Moor granite is definitely delimited by tracing the outer limit of spotting in normal pelitic sediments.

Petrographical study of phyllites from outside this limit shows considerable mineralogical reconstruction in the sediments, with crystallization of white mica, chlorite and chloritoid; in some instances garnet is developed. The distribution of these types shows no relationship to the granite outcrop, but accords with the main structural features of the area.

Analogous changes are prominent in the igneous horizons, with the formation of schists of the general type of prasinite.

Within the aureole thermal effects can be traced superposed on the earlier dynamic changes.

From these lines of inquiry it is concluded that many of the changes in the phyllites, notably the formation of porphyroblastic white mica, chlorite and chloritoid, hitherto ascribed with greater or less finality to the action of the granite, are due to an earlier dynamic metamorphism.
The Carboniferous Limestone Series of West Cumberland
Authors: Edmonds Charles
Published: May 2009

Summary

The examination of the fossil fauna, the chief forms of which are shown in Tables I and II and Fig. 1, shows that the beds commence at a high horizon of the Seminula Zone and extend to the top of the Dibunophyllum Zone. Also, the “life-zones” established by Professor Garwood in his North-Westem Province Paper can be readily recognized in our area and the series includes the sequence from the Nematophyllum minus sub-zone of the Productus corrugatohernisphericus Zone to the Dibunophyllum muirheadi sub-zone of the Dibunophyllum Zone. It can further be established that the limestones of our area do not persist up the horizon of the Botany Beds with Aulina mtiformis S. Smith. The Saccammina Band occurs in our area, but Saccammina occurs also in the limestones immediately above and below. The Girvanella Band of the North-West Province has been recognized and forms a constant horizon throughout the area. It occurs associated with a calcitemudstone and never as a nodular bed. Other bands also appear to be algal. The Spiriferina cf. laminosa Band of Garwood forms a constant horizon between the Seventh and Sixth Limestones.
Liquid Inclusions in Glass
Authors: Benham Charles E.
Published: May 2009

It is well known that the liquid inclusions commonly found in quartz, fluor-spar, and other minerals resemble in some degree those that occur in crystals of sodium chloride, alum, and many salts. Chloride of sodium in particular shows innumerable cavities of varying size, cubical in form (negative crystals), and generally containing an enclosed bubble, especially if heated gently after the crystals are formed. The smaller cavities show Brownian movement of the enclosed bubble in a very striking manner. (See Fig. 1, which gives a diagrammatic view of a salt crystal as seen through the microscope.)
On the Occurrence of Daviesiella llangollensis (Dav.) in Derbyshire
Authors: Jackson J. Wilfrid
Published: May 2009

The object of this paper is to deal more fully with the occurrence of Daviesiella llangollensis (Dav.) in the Carboniferous Limestone of Derbyshire, and further to make some observations on the sequence in the Midland area. In a later paper I hope to deal with the horizon of the “Brachiopod Beds”.
The Cretaceous and Tertiary Question in Jamaica
Authors: Trechmann C. T.
Published: May 2009

The geology of Jamaica compared with that of some areas of the earth's crust is neither very involved nor very difficult of interpretation. Considering the length of time that has elapsed since it was first studied and the easy accessibility of many parts of the island, it should be fairly well known and should form a key for the interpretation of the structure of the larger and less well-known islands of Haiti and Cuba, and also of Porto Rico and the smaller islands forming the group of the Greater Antilles.
The Geology of Portuguese Nyasaland
Authors: Walls Robert R.
Published: May 2009

Portuguese Nyasaland is the name given to the most northern part of Portuguese East Africa, lying between Lake Nyasa and the Indian Ocean. It is separated from the Tanganyika territory in the north by the River Rovuma and from the Portuguese province of Mozambique in the south by the River Lurio. The territory measures about 400 miles from east to west and 200 miles from north to south and has an area of nearly 90,000 square miles. This territory is now perhaps the least known part of the once Dark Continent, but while the writer was actually engaged in the exploration of this country in 1920–1, the Naval Intelligence Division of the British Admiralty published two handbooks, the Manual of Portuguese East Africa and the Handbook of Portuguese Nyasaland, which with their extensive bibliographies contained practically everything that was known of that country up to that date (1920). These handbooks make it unnecessary in this paper to give detailed accounts of the work of previous explorers.
Sedgwick Museum Notes. A New Azygograptus from North Wales
Authors: Elles Gertrude L.
Published: May 2009

The graptolite here described was discovered first in the St. Tudwal's peninsula by Mr. T. C. Nicholas in 1912 in the Llanengan Mudstones, but it was not then regarded as distinct from Azygog. lapworthi, though it seemed to possess certain features not recognizable in the Lake District specimens, the only area from which that species had been previously recorded. The discoveryof numerous other specimens by Dr. Matley in the Lleyn peninsula and by Dr. Greenly in the Bangor area has served to show that the characters wherein this species differed from Azygog. lapworthi are permanent and of specific value, and since, moreover, it occurs at a distinctly higher horizon than Azygog. lapworthi, being characteristic of about the middle of the zone of Didymog. extensus, a description of it seems advisable. In general it has been noted that it is in many respects intermediate in character between Azygog. lapworthi on the one hand and Azygog. suecicus on the other, and it is perhaps significant that it occurs upon an horizon between the two.
The Structure of the South-West Highlands
Authors: Wright W. B. , Anderson E. M. , Richey J. E. , Read H. H.
Published: May 2009

Last summer we spent seven days with Mr. E. B. Bailey investigating some of the evidence upon which he bases his interpretation of the structure of the South-West Highlands, and we feel that our experience should be at the disposal of others interested in the subject. Mr. Bailey's full account of his theory will shortly appear in the Quarterly Journal of the Geological Society of London, and an abstract has already been printed in the Proceedings of that Society, dated April, 1921.
The Petrology of the Pennant Series, East of the River Taff
Authors: Heard A.
Published: May 2009

The occurrence of iron carbonate as a part of the cement in the Pennant Sandstone is not extraordinary, when the large amount of entombed organic matter is taken into consideration. The presence of organic material and the products of decay, the so-called humus acids, acting as reducing agents, would aid in the formation of iron carbonate and prevent its oxidation. Much of this carbonate probably owes its presence to a metasomatic replacement of calcium carbonate. The granules of siderite may have been derived from rocks similar to those of the Lower Coal Series of South "Wales. The alkaline carbonates which hold the humic substances in solution would readily dissolve silica, thus becoming effective agents in the solution and redeposition of silica in the rock. A solvent of this kind would be formed by the impregnation of alkaline salts by carbonic acid.1 The occurrence of so much secondary silica in the rock is probably the result of a redeposition of silica from such a solution. No oxides of iron have been found in any of the numerous separations, either by means of heavy liquids or the electro-magnet; their absence is easily explained when we consider the strongly reducing environment of the deposition and consolidation of the Pennant Sandstone. The perfectly rounded globules of sphserosiderite may have been precipitated whilst the sandstones were being deposited, but more probably derived from the denudation of fireclays similar to those of the Lower Coal Series of South Wales.2 The dominant mineral chlorite, existing as perfect cleavage flakes, is entirely distinct from the secondary aggregates of chlorite in the rock, and was probably deposited in its present form. I have examined a powdered specimen of the Delabole Slates of Cornwall (Upper Devonian), and have found in it a large proportion of chlorite flakes, exactly like the detrital chlorite of the Pennant Sandstone. The very few flakes of biotite found show little trace of alteration. The paucity of heavy minerals indicates that the Pennant sediments had not a granitic source; they were mainly derived from pre-existing sediments which were rich in chert, had abundant chloritic material present, and yet were capable of furnishing fairly fresh biotite. Metamorphosed shales would account for the presence of cordierite and corundum.
Banded Precipitates of Vivianite in a Saskatchewan Fireclay
Authors: Stansfield J.
Published: May 2009

When visiting the fireclay quarry of the Dominion Fire Brick and Clay Products Company at Claybank, Sask., during the summer of 1918, the writer noticed an occurrence of banded precipitatesin the fireclay of one part of the quarry. Through the kindness and courtesy of Mr. H. G. Love, Managing Director of the Company, a collection of some examples of the occurrence was made and forwarded to the writer for further examination.
A New Brachiopod (Leptestia) from the Kuckers Stage in Estonia
Authors: Bekker Hendrik
Published: May 2009

Among the Brachiopoda described in my recent memoir on the Kuckers stage of north-east Estonia, there was an undetermined member of the Strophomenacea, of which the interior of the dorsal valve was unknown. I have since found a dorsal valve with its exterior (concave) outwards, embedded in kuckersite. By filling the concavity with plaster of Paris the shell could be easily removed from the kuckersite. A complete description can now, therefore, be given. Since my return to Estonia I have found additional examples of the same species and of another species of the same genus amoug the collections of the Tartu (Dorpat) Museum, which were removed into Russia during the war, and have now been returned.
V.—Some Cirripedes from the Chalk of Salisbury, Wilts
Authors: Withers Thomas H.
Published: May 2009

Although the remains of pedunculated Cirripedes are comparatively rare in the Chalk of England, especially in its lower zones, one can, by careful collecting extended over a number of years, get together a fair series of the detached valves of the capitulum. Thus a very fine series of Cirripede remains has been accumulated by Dr. H. P. Blackmore, F.G.S., from the upper zones of the Chalk near Salisbury. This collection, which, through the kindness of Dr. Blackmore, I have lately had the opportunity of examining, is especially rich in the valves of Scalpellum fossula, Darwin, and S. maximum (J. de C. Sowerby).
I.—Calcite as a Primary Constituent of Igneous Rocks
Authors: Workman Rachel
Published: May 2009

During one of the excursions arranged by the International Geological Congress held in Sweden, 1910, we visited, under the leadership of Professor Högbom, a group of islands skirting the shore north of Sundsvall, on the Gulf of Bothnia. Among these islands Alnö and Långörsholmen are of particular interest on account of a complex of alkali igneous rocks forming the whole of the latter and the northern corner of the former. It is to this small but highly interesting group of rocks that I wish to call the attention of the reader, since apart from the short but convincing ‘guide’ prepared by Professor Högbom (1), scarcely anything has been written on the subject in the English language. The expedition was very skilfully planned, and we were thus enabled to visit several critical exposures and collect numerous specimens for microscopic study.
II.—The Fundamental Problems of Petrogenesis, or the Origin of the Igneous Rocks
Authors: Lœwinson-Lessing Franz
Published: May 2009

The question of the origin of igneous rocks, their diversity and genetic relationships, represents that fundamental problem of petrography which has been for many years the object of inquiry for petrologists as well as for geologists and chemists. Whilst the amount and scope of detailed observation were growing, the methods of experimental investigation improved, and as the eruptive rocks came to be studied from the point of view of physical chemistry, so the petrogenetical horizon became larger and wider. Thus, on the basis of numerous minute and detailed observations were built broad generalizations that gave rise to new problems.
V.—Modern ‘Vulcanicity.’
Authors: Ward J. Clifton
Published: May 2009

The theory proposed of late years by Mr. Mallet to account for volcanic and earthquake phenomena, while having a charm about it from its very simplicity, is one which must nevertheless meet with very decided criticism from geologists.
VI.—On Two Trilobites from the Devonian Slates of Cornwall, Obtained by Walter Barratt, Esq
Authors: Woodward Henry
Published: May 2009

Having been favoured by Mr. Walter Barratt, of Sunnybank, Newquay, Cornwall, with the opportunity of examining two Trilobites from the Devonian slate-rock—(1) from a cove near Trevose Head, (2) from the shore of the mainland opposite Trescore Island, Porthcothan, Cornwall,—I gladly avail myself of his permission to publish a note thereon.
III.—The Composition of Indian Laterite
Authors: Warth H. , Warth F. J.
Published: May 2009

After the appearance of Mr. T. H. Holland's paper on Laterite in the Geological Magazine, February number (pp. 59–69), we can at once give the results of our analysis of Indian laterite, without further introductory remarks. They are as follows:—
III.—The Purbeck Beds of the Vale of Wardour
Authors: Jukes-Browne A. J.
Published: May 2009

The paper written by the Rev. W. R. Andrews and myself, published in 1894, gave a more complete account of these beds than had previously been attempted; we showed that they were divisible into Lower, Middle, and Upper groups, comparable with those established by Professor E. Forbes in the Purbecks of Dorset, and characterized by the same species of Cyprides. This paper was based on the joint examination of exposures visible in 1890, though one of us, being then resident at Teffont, had observed and collected from these exposures for many years.

In the following year (1895) Mr. H. B. Woodward's memoir on the “Middle and Upper Oolitic Rocks” was published, and his account differed from ours in several particulars, notably as regards the thickness of beds referable to the three several divisions, as to the interpretation of the section near Dinton Station, and as to the total thickness of the formation. We refrained from comment at the time, partly because we were prepared to accept such corrections as were based on the freshly cut exposure near Dinton, and partly because the mapping of the distriot had not then been completed, and we were content to wait till this was done, in the expectation that Mr. Woodward would then reconsider some of the points on which we were not in agreement with him.

The mapping of the area was completed in 1900 by Mr. C. Keid, and this year (1903) the map (Sheet 298, new series), together with an explanatory memoir prepared by Mr. Reid, have been published.
IV.-—The Disappearance of Limestones in High Teesdale
Authors: Clough C. T.
Published: May 2009

In High Teesdale, on certain hillsides, the structure of which is in most respects clear, the observer is struck by the disappearance of some, generally constant, limestone which ought naturally to occur. The limestone most usually missing is the Great Limestone, which, with the exception of the Melmerby Scar Limestone, is the thickest of all in the dale. Though the ground is almost free from peat and drift, and plainly shows the banks formed by the Four Fathom Limestone and Firestone, there is yet perhaps neither bank nor ‘shake-hole’ (swallow-hole) to represent the Great Limestone. In the cases referred to the difficulty cannot be accounted for by supposing that the limestone along its outcrop is thrown out by a fault, for the outcrops of the beds above and below can be followed round the hill without interruption.
III.—A Revision of some Carboniferous Corals
Authors: Carruthers R. G.
Published: May 2009

Corallum conical and, as a rule, gently curved, though often straight; a short broad outline is not uncommon. The epitheca has well-marked longitudinal ribbing, sometimes obscured by fine annular striations in the neighbourhood of the calyx; slight constrictions of growth may occur, but there is never an interrution in the continuity of the epitheca. Good figures are given both by Milne-Edwards & Haime and by de Koninck.
Oblique and Orthogonal Sections of a Folded Plane
Authors: Fisher O.
Published: May 2009

In the tenth volume of this Magazine, a correspondence appeared upon the subject of “True and Apparent Dip,” which was started by Mr. Penning, and continued by several able geologists. The object of the present article is to call attention to another branch of the same subject. We are all acquainted with “Sopwith's Models,” in which are experimentally shown the outcrops, or “traces,” of plane strata upon variously curved surfaces. We now are about to refer to the outcrop of curved strata upon a plane surface. I was led to examine this question from the following circumstances.
V.—Oceanic Islands
Authors: Reade T. Meelard
Published: May 2009

The Pacific and Atlantic Oceans far from the continental masses of land are studded with islands, which from their being solely volcanic and of an age going back no further than the Tertiary period, are considered to lend great support to the hypothesis of the permanence of the great oceans and continents. Those who hold these views question the right of New Zealand to be considered a truly oceanic island, though on what grounds has never been quite intelligible to me. Waiving this objection for the purpose of argumeat, I propose to discuss the bearings of the facts, as formulated by those who believe in the “approximate” immutability of land and sea.
III.—On a Case in which various massive Crystalline Rocks including Soda-Granite, Quartz-Diorite, Norite, Hornblendite, Pyroxenite, and different Chrysolitic Rocks, were made through Metamorphic Agencies in one Metamorphic Process
Authors: Dana James D.
Published: May 2009

The above brief description of the Cortland rocks prepares the way for a consideration of their relation to the other rocks of the county. The following questions arise: Are they one with the latter in system ? are they rocks of an earlier system ? or are they eruptive rocks, and not metamorphic, and hence, of no bearing on the general question as to the age of the Westchester limestones and the associated schists ?
IV.—Contributions to the Palæontology of the Yorkshire Oolites.
Authors: Hudleston Wilfrid. H.
Published: May 2009

In England the Great Oolite of Minchinhampton contains the greater number of species belonging to this peculiar group of Haliotidœ. Morris and Lycett (Great Oolite Mollusca, p. 80) give a full and interesting diagnosis of the genus, which has oniy one representative in the Corallian beds of Yorkshire. D'Orbigny figures half a dozen species of Troehotoma from the Corallian of France, and Buvignier gives three from the Coral Rag of the Meuse. None are quoted by Be Loriol from the Séquanien of Boulogne.
VI.—Laccolites
Authors: Kinahan G. H.
Published: May 2009

In the Report on the Geology of the Henry Mountains, Rocky Mountain Region, Mr. G. K. Gilbert, of the U.S. Geographical and Geological Survey, points out that many of the intrusions of eruptive rocks now exposed had a deep-seated origin; the molten rock having filled vacancies in the rocks, and never coming to the surface until they were exposed by denudation or by faults. To quote our author, “The lava … instead of rising through all the beds of the earth's crust, stopped at a lower horizon, insinuated itself between two strata, and opened for itself a chamber by lifting all the superior beds. For these masses of eruptive rocks, Gilbert proposes the name laccolite (Gr. lakkos cistern, and lithos stone). In the Cos. Wexford and Wioklow some of the protrusions of eruptive rocks are entitled to this name, the rocks having congealed in cisterns below the surface of the earth; there are, however, some marked differences between them and the laccolites of the Henry Mountains. The latter were intruded into nearly horizontal strata, the laccolites only consist of one kind of rock, while the adjoining rocks seem to have been very little altered. But the Wexford and Wicklow laccolites, on the other hand, were intruded into highly disturbed strata, they are made up of a variety of rocks, and always the aquo-igneous action due to their intrusion—‘ baked ’ or altered, a greater or less thickness of rocks about them.
VI.—Note on the Carboniferous System in Britain
Authors: Jones T. Rupert
Published: May 2009

In comparing the relative thicknesses of the Welsh-English and the Scotch Carboniferous series for lecture notes, I have found it difficult to obtain from books definite statements on this point as regards some groups of these strata in Scotland. After considerable reading I gather the following information.
I.—Note on a Nepheline-Syenite Boulder dredged from the Atlantic
Authors: Workman McRobert Rachel
Published: May 2009

Through the kindness of Dr. Flett there has come into my hands an interesting boulder of nepheline-syenite belonging to Sir John Murray, dredged during the expedition of theMichael Sars(1) from the Atlantic Rise at a depth of 1,750 fathoms at a place about 150 miles south-west of the south-western corner of Ireland (Station 95 of the Reports of theMichael SarsExpedition). The slices examined were slides Nos. F 2092 to F 2095 from the Geological Survey Collection and two belonging to Dr. Peach. It is a boulder of remarkable freshness, and so entirely unlike any other specimen as yet recorded from the floor of the Atlantic that the question of its origin is of some interest. The fact that no other fragments of the same type were obtained in this dredging militates against the view that it is part of a mass in situ on the sea-bottom. Its companions from the same station, and in fact all the specimens collected by theMichael Sars, have been recognized by Dr. Peach and Dr. Flett as similar to rocks occurring commonly in Ireland, the North-West Highlands, and the Southern Uplands of Scotland, and not one among them is closely related to the nepheline-syenite. Bocks of Irish types have also been described by Professor Cole and Mr. Crook (2) as a result of earlier dredgings of the Atlantic floor, and again no specimen has been found remotely resembling the subject of this paper.
III.—Notes on new or imperfectly known Chalk Polyzoa
Authors: Brydone R. M.
Published: May 2009

Zoarium small, highly conical, slightly compressed in one direction, very fragile.

Zoœcia rather bluntly hexagonal, subradially arranged in straight rows which from time to time diverge to admit a new row, length ·35–·4mm., width about the same; the area varies from distinctly elliptical to practically circular; maximum length ·33 mm., breadth ·3 mm.
V.—Outlines of Oilfield Geology
Authors: Bosworth T. O.
Published: May 2009

It is remarkable that in English geological literature and in our Universities so little attention is given to this important branch of geology. Probably it is because in this country petroleum occurs only in small quantity; nevertheless, in many parts of the British Empire petroleum mining has become a great and increasing industry, and is one of the chief directions in which geology is of practical use to-day. The writer therefore hopes that an orderly summary of present knowledge may be useful.
II.—On the Interglacial Gravel Beds of the Isle of Wight and South of England, and the Conditions of their Formation
Authors: Hull Edward
Published: May 2009

Previous Authorities.—The most important work dealing with my subject is that by Mr. Thomas Codrington “On the Superficial Deposits of the South of Hampshire and the Isle of Wight”. In this elaborate essay, which includes all the area with which I propose to deal, the author describes the gravel terraces on both sides of the Solent, including the New Forest, showing how they were originally distributed over surfaces gradually sloping downwards on both sides towards the margin of the sea-coast from a height of about 420 feet on either hand. In the author's view, the plateau gravel beds were spread as sheets over sloping surfaces, themselves intersected by river-valleys which were widened and deepened at a subsequent period after the deposition of the beds of gravel, so as to leave abrupt faces and cliffs exposing sections of the strata. The paper, which is illustrated by sections, leaves nothing to be desired for completeness; but in order to account for the deposition of the gravel-beds he propounds a theory which I am unable to accept.
IV.—Note on the Molar Tooth of an Elephant from the Bed of the Nile, near Khartum
Authors: Andrews C. W.
Published: May 2009

In sinking the caissons for the construction of the bridge over the Blue Nile near Khartum, a considerable number of bones have been found, from time to time, in the alluvial beds, at depths of 60–68 feet below the level of low Nile. These specimens were obtained by Messrs. Hinckley, Stephen, and Le Bailly, and are now deposited in the collection of the Geological Survey of the Sudan at Khartum.
V.—The Age of the Morte Slates
Authors: Evans J. W. , Pocock R. W.
Published: May 2009

The discovery by Professor Reynolds in the Mendips strata representing the greater portion of the Silurian succession (Rep. Brit. Assoc. Portsmouth, 1911), showing no similarity to the slates of Mortehoe and the neighbourhood, has rendered it more difficult than ever to accept the attribution by Dr. Hicks of the latter rocks to the Silurian period (Q.J.G.S., vol. lii, p.254, 1896); and now an important fact has come to light which appears to afford decisive evidence on this question.
I.—Eminent Living Geologists
Authors: Carruthers William
Published: May 2009

If we review the progress of any one of the natural sciences we shall find it is but the outcome of the genius and labours of many individual workers, who have devoted themselves for years to some particular branch of discovery or research. Taking palæobotany as an illustration, we may cite the name of William Carruthers as a striking example of an individual worker in that field, who, during more than a quarter of a century, specially devoted himself to the investigation and description of fossil plants, and has thus added largely to a knowledge of this section of the science of palæontology.
III.—On the Geology of Venezuela
Authors: Dalton Leonard V.
Published: May 2009

Although the Republic of Venezuela adjoins two British colonies, only some three or four papers have been published in English journals dealing with the geology of the country. These, moreover, are concerned with local observations, and no attempt at correlation has been made. A considerable mass of material is available in Continental publications, and the author, during a series of journeys through Northern Venezuela in 1910, was able to collect sufficient data to form a fairly clear idea of the successien of deposits, and to roughly correlate the views of different writers. While more compilatory than original, the following paper is offered as a basis for further study of the geology of an area so closely connected with the colonies of British Guiana and Trinidad, and the short bibliography includes all those papers bearing directly on the subject which are known to the author.
VI.—The Plates of the Buccal Membrane in Echinocorys
Authors: Hawkins Herbert L.
Published: May 2009

A Specimen of Echinocorys showing the plates of the peristome was exhibited at the Conversazione of the Geologists' Association in 1910 by Mr. W. H. Bennett, and has, through the courtesy of that gentleman, been forwarded to me for detailed examination. In view of the perfect preservation of the peristomial structures, and the extreme rarity of their discovery, I have thought it advisable to publish the following short description. A comparison is made between the structure shown in this specimen and that described by Lovén in the young stages of Echinocardium.
II.—The New Mountain of the Year 1910, Usu-san, Japan
Authors: Bailey E. B.
Published: May 2009

The writer's attention was directed to Dr. Omori's description of the 1910 eruption of Usu-san through a review which appeared in Nature (1911, p. 221) from the pen of Professor Milne, F.R.S. The following pages constitute a résumé, rather than an additional review, and are justified on account of the interest of Omori's observations to many geologists who may not find it convenient to consult his original paper. All three figures here published have been redrawn for the purpose. Plate XII is based on a coloured map, and Plate XIII on photographs which have already been reproduced by Professor Milne in his review.
I.—The End of the Trimingham Chalk Bluff
Authors: Bonney T. G. , Hill E.
Published: May 2009

During the last six years the sea has continued to encroach on a part of the Norfolk coast, near Trimingham, which has been the subject of much controversy. Our last visit (prior to this year) was in April, 1906, when the most noted of the chalk masses had been reduced to an arch with one pier of chalk and the other of boulderclay. That was described (with a diagram), and another account, with a photographic illustration, was given in the same volume by the late Mr. W. H. Hudleston, who apparently had not seen our paper.
III.—A New Species of Fibularia from Nigeria
Authors: Hawkins Herbert L.
Published: May 2009

Among a series of fossils collected in Southern Nigeria by Mr. A. E. Kitson, and submitted by him to the authorities at the British Museum, are some small Echinoids. Dr. Bather has kindly allowed me to examine them, and, as they appear to belong to a new species, I have drawn up the following description. For reasons stated below I ascribe the forms to the genus Fibularia, Lamk., and consider all the specimens to belong to the same species. Ten individuals have been used for the purposes of the description, but, to prevent possible confusion, I select that numbered A as the type-specimen.