Carboniferous Sentence Examples

Jager has described coprolites from the alum-slate of Gaildorf in Wurttemberg; the fish-coprolites of Burdiehouse and of Newcastle-under-Lyme are of Carboniferous age.

The mountains both in Victoria and New South Wales were snow-capped, and glaciers flowed down their flanks and laid down Carboniferous glacial deposits, which are still preserved in basins that flank the mountain ranges, such as the famous conglomerates of Bacchus Marsh, Heathcote and the Loddon valley in Victoria, and cf Branxton and other localities in New South Wales.

The Permian deposits are best developed in New South Wales and Tasmania, where their characters show the continuation of the Carboniferous conditions.

It has been ascertained from recent explorations that the area of carboniferous formation in that state extends from the Irwin northwards to the Gascoyne river, about 300 m., and probably all the way to the Kimberley district.

The limestone has yielded Proetus, Chonetes and other fossils, and is believed to be of Carboniferous age.

Secondly, the histology of fossil plants, particularly woody plants of the carboniferous period, has been placed on a sound basis, assimilated with general histological doctrine, and has considerably enlarged our conceptions of plant anatomy as a whole, though again.

In the British Islands native sulphur is only a mineralogical rarity, but it occurs in the Carboniferous Limestone of Oughterard in Co.

The Coleoptera can be traced back farther in time than any other order of insects with complete transformations, if the structures that have been described from the Carboniferous rocks of Germany are really elytra.

In the Moscow basin, which was a broad gulf of the Carboniferous sea, coal appears as isolated inconstant seams amidst littoral deposits, the formation of which was favoured by frequent minor subsidences of the seacoast.

The coal is here confined to the lower division of the system; the Upper Carboniferous (corresponding with the English Coal-Measures) is exclusively marine, consisting chiefly of Fusulina limestone.

Europe generally, the principal coal seams occur in the Upper Carboniferous, while the Lower Carboniferous is mainly composed of marine deposits, with, however, the first bed of coal near its summit.

The Polish coalfields belong to another Carboniferous area of deposit, which extended over Silesia.

In the extreme north-east are found the oldest rocks in the state - lower Devonian (the New Scotland beds of New York) and, not so old, an extension of the Lower Carboniferous which underlies the Warrior coalfields of Alabama, and which consists of cherts, limestones, sandstones and shales, with a depth of 800 to 900 ft.

The latter is, no doubt, identical with the similar sandstone series which is found in the neighbouring Brazilian province of Rio Grande do Sul, and which has there yielded plants which prove it to belong to the Permian or the upper part of the Carboniferous.

There is again a floor of folded Archean rocks overlaid by nearly horizontal strata of Lower Palaeozoic age; but these are followed by marine beds belonging to the Carboniferous period.

From the Upper Carboniferous onward, however, no marine deposits are known; and, as in Siberia, plant-bearing beds are met with.

Thus it appears that from the Arctic Ocean there stretches a broad area as far as the south of China, in which no marine deposits of later date than Carboniferous have yet been found, except in the extreme north.

Marine Tertiary beds occur in Burma; in the Himalayas and in south Tibet there is a nearly complete series of marine deposits from the Carboniferous to the Eocene; in Afghanistan the Mesozoic beds are in part marine and in part fluviatile.

A bone bed has also been observed at the base of the Carboniferous limestone series in certain parts of the south-west of England.

The principal structural feature is the broad anticline, its axis running north and south, which has brought up the Carboniferous Limestone; this uplifted region is the southern extremity of the Pennine Range.

The Carboniferous or "Mountain" Limestone is the oldest formation in the county; its thickness is not known, but it is certainly over 2000 ft.; it is well exposed in the numerous narrow gorges cut by the Derwent and its tributaries and by the Dove on the Staffordshire border.

In the Carboniferous strata (Coal measures) remains of Hexapods become numerous and quite indisputable.

It is probable that many of these Carboniferous insects might be referred to the Isoptera, while others would fall into the existing orders to which they are allied, with some modification of our present diagnoses.

From the Trias of Colorado, Scudder has described cockroaches intermediate between their Carboniferous precursors and their present-day descendants, while the existence of endopterygotous Hexapods is shown by the remains of Coleoptera of several families.

We have undoubted fossil evidence that winged insects lived in the Devonian and became numerous in the Carboniferous period.

As shown by the number and variety of species, the Orthoptera are the most dominant order of this group. Eminently terrestrial in habit, the differentiation of their fore-wings and hindwings can be traced from Carboniferous, isopteroid ancestors through intermediate Mesozoic forms. The Plecoptera resemble the Ephemeroptera and Odonata in the aquatic habits of their larvae, and by the occasional presence of tufted thoracic gills in the imago exhibit an aquatic character unknown in any other winged insects.

Geologically, spiders date from the Carboniferous Period, Arthrolycosa and others from the coal beds of Europe and North America being closely allied to the existing genus Liphistius.

It should be pointed out that the deposits which have been hitherto of chief commercial importance occur in the old rocks (Carboniferous to Silurian) on the one hand, and in the comparatively new Tertiary formations on the other, the intermediate periods yielding but little or at any rate far less abundantly.

In Palestine a limestone containing Carboniferous fossils is found in the midst of the sandstone series, and here the sandstone is immediately succeeded by limestones with Hippurites and other fossils belonging to the Upper Cretaceous.

It is, however, likely that this formation occurs in Greenland, for in Dana Bay, Captain Feilden found a species of Spirifera and Productus mesolobus or costatus, though it is possible that these fossils represent the " Ursa stage " (Heer) of the Lower Carboniferous.

In erratic blocks of sandstone, found on the Disco shore of the Waigat, have been detected a Sigillaria and a species of either Pecopterisor Gleichenia, perhaps of this age; and probably much of the extreme northern coast of Ellesmere Land, and therefore, in all likelihood, the opposite Greenland shore, contains a clearly developed Carboniferous Limestone fauna, identical with that so widely distributed over the North American continent, and referable also to British and Spitsbergen species.

Ephemeridae belong to a very ancient type of insects, and fossil imprints of allied forms occur even in the Devonian and Carboniferous formations.

The principal folding took place at the close of the Carboniferous period, and was contemporaneous with that of the old Hercynian chain of Belgium, &c. The Permian and later beds lie unconformably upon the denuded folds, and in the space between the Montagne Noire and the Cevennes proper the folded belt is buried beneath the horizontal Jurassic strata of the Causses.

The Trilobites are known only as fossils, mostly Silurian and prae-Silurian; a few are found in Carboniferous and Permian strata.

They became extinct in Palaeozoic times, and are chiefly found in the Upper Silurian, though extending upwards as far as the Carboniferous.

Appendages of 1st pair.tri-segmented, chelate; of 2nd pair chelate, with their basal segments subserving mastication; of 3rd, 4th, 5th and 6th pairs similar in form and function, except that in recent and Carboniferous forms the basal segments of the 3rd and 4th are provided with sterno-coxal (maxillary) lobes, those of the 4th pair meeting in the middle line and underlying the mouth.

Fossil forms occur in the Carboniferous.

Protolycosa and Arthrolycosa occur in the Carboniferous.

Apparently related to the Opiliones are two extinct groups, the Anthracomarti and Phalangiotarbi, which are not known to have survived the Carboniferous period.

In the basin of the Lower Amazon the Carboniferous beds lie within the Devonian synclinal and crop out on both sides of the river next to the Devonian bands.

The former appears to be almost unfossiliferous, the latter has yielded a rich marine fauna, which belongs to the top of the Carboniferous or to the Permo-carboniferous.

The beds are homotaxial with the Karharbari series of India, and represent either the top of the Carboniferous or the base of the Permian of Europe.

Eruptive rocks occur in the Devonian and Carboniferous beds, but there is no evidence of volcanic activity since the Palaeozoic epoch.

It stands on undulating and easily drained ground, upon a bed of sandstone rock, on a peninsula jutting into one of the deepest, safest and most beautiful harbours in the world; and in addition it lies in the centre of a great carboniferous area.

The Vosges, and their continuation the Hardt, run through the land from south to north and divide it into the fertile and mild plain of the Rhine, together with the slope of the Hardt range, on the east, and the rather inclement district on the west, which, running between the Saarbriick carboniferous mountains and the northern spurs of the Hardt range, ends in a porphyrous cluster of hills, the highest point of which is the Donnersberg (2254 ft.).

Gneiss and granite occur; Ordovician fossils have been found in the Upper Shan States, and Carboniferous fossils in Tenasserim and near Moulmein.

Carboniferous rocks are represented by mountain masses of Fusulina and other limestones.

The oldest beds which have yielded fossils in any abundance belong to the Carboniferous System.

Between this lowland and Armagh city, the early Cainozoic basalts form slightly higher ground, while on the west a strip of Trias appears, overlying Carboniferous Limestone.

The Carboniferous Limestone beneath it and around it is red-brown instead of grey, and is famous for its richness in fish remains.

In the western Carpathians the inner zone consists of a foundation of Carboniferous and older rocks, which were folded and denuded before the deposition of the succeeding strata.

Both Heteropterous and Homopterous genera have been described from the Carboniferous, but the true nature of some of these is doubtful.

In its most general sense the term " coal " includes all varieties of carbonaceous minerals used as fuel, but it is now usual in England to restrict it to the particular varieties of such minerals occurring in the older Carboniferous formations.

Hydrocarbons, such as petroleum, bitumen, paraffin, &c., are also found occasionally in coal, but more generally in the associated sandstones and limestones of the Carboniferous formation.

This is actually the case; the Carboniferous, Cretaceous and Jurassic systems (qq.v.) contain coal-bearing strata though in unequal degrees,- the first being known as the Coal Measures proper, while the others are of small economic value in Great Britain, though more productive in workable coals on the continent of Europe.

The commencement of the Carboniferous period is marked by a mass of limestones known as the Carboniferous or Sequences Mountain Limestone,which contains a large assemblage of carbon- of marine fossils, and has a maximum thickness in iferous S.W.

The Coal Measures, forming the third great member of the Carboniferous series, consist of alternations of shales and sandstones, with beds of coal and nodular ironstones, which together make up a thickness of many thousands of feet - from 12,000 to 14,000 ft.

The eastern part of the Prairie Plains is a belt known as the Black Prairie, and it has a rich black soil derived from Upper Cretaceous limestone; immediately west of this is another belt with a thinner soil derived from Lower Cretaceous rocks; a southern part of the same plains has a soil derived from granite; in a large area in the north-west the plains have a reddish clay soil derived from Permian rocks and a variety of soils - good black soils and inferior sandy and clay soils - derived from Carboniferous rocks.

Geologically the region is made up of Carboniferous limestones, clay slates and sandstones, containing anthracite and coal; of Cretaceous marls, chalk, sandstone and greensands - chalk cliffs, in fact, accompany the Don for 200 m.; and of Miocene limestones and clays.

The Carboniferous system includes either the whole or a large part of the Maitai beds.

The Maitai beds have generally been considered to be Carboniferous from the presence of species of Productus found in the Permo-Carboniferous of New South Wales.

But Professor Park has obtained Jurassic fossils in the Maitai series; so that it will probably be ultimately divided between the Carboniferous and Jurassic. The two systems should, however, be separable by an unconformity, unless the Maitai series also includes representatives of the Kaihiku series (the New Zealand Permian), and of the Wairoa series, which is Triassic.

Interesting fossil remains have also been found in Carboniferous formations in the south-west of the state.

Near Dinant carboniferous beds are infolded among the Devonian.

The southern boundary of this belt is formed by a great thrust-plane, the faille du midi, along which the Devonian beds of the south have been thrust over the carboniferous beds of the coalfield.

Manganese could be readily worked in Timor, where it lies in the Carboniferous Limestone.

At Cushendun, however, a coarse conglomerate is believed to be Devonian, while Lower Carboniferous Sandstones, with several coal-seams, form a small productive basin at Ballycastle.

The dolerite of Fair Head sends off sheets along the bedding-planes of these carboniferous strata.

Slates belong mostly to the older geological systems, being commonest in Pre-Cambrian, Cambrian and Silurian districts, though they may be found of Carboniferous or even of Tertiary age, where mountain-building processes have folded and compressed these more recent formations.

Carboniferous and Permian strata are possibly represented by some black and grey micaceous shales with beds of coal in the Jurjura.

Similarly, the Mesozoic reptiles have been traced successively to various parts of the world from France, Germany, England, to North America and South America, to Australia and New Zealand and to northern Russia, from Cretaceous times back into the Permian, and by latest reports into the Carboniferous.

The earliest fossiliferous beds which have been proved to exist in Mexico belong to the Carboniferous system.

In the lead-mining districts of Derbyshire and the north of England the ore occurs as veins and flats in the Carboniferous Limestone series, whilst in Cornwall the veins traverse clay-slates.

An important geological characteristic of most of the Cordilferan region is that the Carboniferous strata, which in western Europe and the eastern United States contain many coal seams, are represented in the western United States by a marine limestone; and that the important unconformity which in Europe and the eastern United States separates the Palaeozoic and Mesozoic eras does not occur in the western United States, where the formations over a great area follow in conformable sequence from early Palaeozoic through the Mesozoic.

The results of the first cycle of erosion are seen in the widespread exposure of the resistant Carboniferous limestone as a broad platform in the south-western area of greater uplift through central Arizona, where the higher formations were worn away; and in the development of a series of huge, south-facing, retreating escarpments of irregular outline on the edges of the higher formations farther north.

A wonderful series of these forms occurs in southern Utah, where in passing northward from the Carboniferous platform one ascends in succession the Vermilion Cliffs (Triassic sandstones), the ViThite Cliffs (Jurassic sandstones, of remarkably cross-bedded structure, interpreted the dunes of an ancient desert), and finally the Pink Cliffs (Eocene strata of fluviatile and lacustrine origin) of the high, forested plateaus.

Mississippian SystemThe Mississippian system was formerly regarded as a part of the Carboniferous, and was described under the name of Lower Carboniferous, or Subcarboniferous, without the rank of a system.

This older classification, which has little support except that which is traditional, is still adhered to by many geologists; hut the fact seems to be that the system is set off from the Pennsylvanian (Upper Carboniferous) more sharply than the Cambrian is from the Ordoviciao, the Silurian from the Devonian, or the Devonian from the Mississippian.

Pennsylvanian SystemThe Pennsylvanian or Upper Carboniferous system overlics the Mississippian unconformably over a large part of the United States.

Geologically the anthracite and bituminous coals mainly belong to the same formation, the Carboniferous, and this is especially true of the better qualities; though it is stated by the United States Geological Survey that the geQlogic age of the coal beds ranges from Carboniferous in the Appalachian and Mississippi Valley provinces to Miocene (Tertiary) on the Pacific coast, and that the quality of the coal varies only to a very uncertain degree with the geologic age.

The province of New Brunswick exhibits approximately parallel but subordinate ridges, with wide intervening areas of nearly flat Silurian and Carboniferous rocks.

In New Brunswick the Carboniferous rocks occupy a large area, but the coal seams so far developed are thin and unimportant.

Atnina; fossil and recent, from Carboniferous to present day.

The Plecoptera are world-wide in their range and fossils referable to them have been described from rocks of Eocene, Miocene and Jurassic age, while C. Brongniart states that allied forms lived in the Carboniferous Period.

Hagen observed that some genera possess wing-like outgrowths on the prothorax, comparable to those seen in certain insects of the Carboniferous Period.

These beds, with intercalated lavas, form the mountainous west shore of Lough Mask, the east, like that of Lough Corrib, being formed of low Carboniferous Limestone ground.

Clew Bay, with its islets capped by glacial drift, is a submerged part of a synclinal of Carboniferous strata, and Old Red Sandstone comes out on the north side of this, from near Achill to Lough Conn.

Several of the western counties contain Carboniferous or sub-Carboniferous sandstones that are used locally for building and for various other purposes.

These rocks were originally referred to the Carboniferous system, and similar limestones have been recorded in many parts of the island.

The age of a great part of the Palaeozoic belts is somewhat uncertain, but Permian, Carboniferous, Devonian and Silurian fossils have been found in various parts of the chain, and it is not unlikely that even the Cambrian may be represented.

But it is divided longitudinally by a well-marked belt of stratified deposits, known as the zone of the Briangonnais, composed chiefly of Carboniferous, Triassic and Jurassic beds.

He was distinguished for his researches on the Carboniferous and Cretaceous rocks and fossils of Saxony, and in particular for those relating to the fauna and flora of the Permian or Dyas formation.

In this case the carbonaceous beds-coal-seams-naturally appealed most strongly to the imagination, and the name is a good one, notwithstanding the fact that coal-seams occupy but a small fraction of the total thickness of the Carboniferous system; and although subsequent investigations have demonstrated the existence of coal in other geological formations, in none of these does it play so prominent a part.

In many parts of the world there is no sharp line of demarcation between the Devonian and the Carboniferous rocks; neither can the fossil faunas and floras be clearly separated at any well-defined line; this is true in Britain, Belgium, Russia, Westphalia and parts of North America.

Again, at the summit of the Carboniferous series, both the rocks and their fossil contents merge gradually into those of the succeeding Permian system, as in Russia, Bohemia, the Saar region and Texas.

There seems to be sufficient reason, however, to maintain each of these groups as a separate system and limit the term Carboniferous (carboniferien) in the manner indicated above.

At the same time it must be remembered that there is in India, South Africa, the Urals, in Australasia and parts of North America an important series of rocks, with a " Permo-Carboniferous " fauna, which constitutes a passage formation between the Carboniferous, sensu stricto, and Jurassic rocks.

No assemblage of stratified rocks has received such careful and detailed examination as the Carboniferous system; consequently our knowledge of the stratigraphical sequence in isolated local areas, where the coals have been exploited, is very full.

The area within which the Carboniferous rocks of Britain occur is sufficiently extensive to contain more than one type of the system, and thus to cast much light on the varied geographical conditions under which these rocks were accumulated.

In prosecuting the study of this part of British geology it is soon discovered, and it is essential to bear in mind, that, during the Carboniferous period, the land whence the chief supplies of sediment were derived rose mainly to the north and north-west, as it seems to have done from very early geological time.

Hence vertical sections of the Carboniferous formations of Britain differ greatly according to the districts in which they are taken.

The Coal-Measures and Millstone Grit are usually grouped together in the Upper Carboniferous, the Carboniferous Limestone series constituting the Lower Carboniferous.

Besides the considerable exposed area of Carboniferous rocks in Great Britain, there is as much or more that is covered by younger formations; this is true particularly of the eastern side of England and the south-eastern counties, where the coal-measures have already been found at Dover.

From England, Carboniferous rocks can be followed across northern and central France, into Germany, Bohemia, the Alps, Italy and Spain.

The fossil plants connect this group with the coal-measures; the marine fossils have, to some extent, a Carboniferous limestone aspect.

The thick, main or scaur limestone (mountain limestone) of the centre and south of England, Wales and Carboniferous Ireland, which splits up in the Yorkshire dales C Limestone (Yoredale group) into a succession of stout limestone Li Series.

In subdividing the strata of the Carboniferous system and correlating the major divisions in different areas, just as in other great systems, use has to be made of the fossil contents of the rocks; stratigraphical units, based on lithology, are useless for this purpose.

The groups of organisms utilized for zoning and correlation by different workers include brachiopods, pelecypods, cephalopods, corals, fishes and plants; and the results of the comparison of the faunas and floras of different areas where Carboniferous rocks occur are generalized in the table below.

The sequence of Carboniferous strata is not everywhere one of unbroken continuity.

In the eastern border of the Rhenish Schiefergebirge the Permian rests unconformably upon Lower Carboniferous rocks.

United States, in Missouri, Pennsylvania, West Virginia, Kentucky, Ohio and elsewhere, there is an unconformable junction between the Lower and Upper Carboniferous, representing an interval of time during which the lower member was strongly eroded; it has even been proposed to regard the Mississippian (Lower Carboniferous) as a distinct geological period, mainly on account of this break in the succession.

In the Eurasian land area the greatest thickness of Carboniferous rocks is in the west; in North America it is in the east.

In Britain the Carboniferous limestone series is 2000-3500 ft.

The Upper Carboniferous in Lancashire is from 12,000 to 13,000 ft.; elsewhere in Britain it is thinner.

In Colorado the Lower Carboniferous is only 400-500 ft.

We have seen that in the Carboniferous rocks there are two phases of sedimentation, the one marine, the other continental; corresponding with these there are two distinct faunal facies.

For the first time in the earth's history we find Foraminifera taking a prominent part in the marine faunas; the genus Fusulina was abundant in what is now Russia, China, Japan, North America; Valvulina had a wide range, as also had Endothyra and Archaediscus; Saccammina is a form well known in Britain and Belgium, and many others have been described; some Carboniferous genera are still extant.

Many fish inhabited the Carboniferous seas and most of these were Elasmobranchs, sharks with crushing pavement teeth (Psammodus), adapted for grinding the shells of brachiopods, crustaceans, &c. Other sharks had piercing teeth (Cladoselache and Cladodus); some, the petalodonts, had peculiar cycloid cutting teeth.

The Arthrodirans, so prominent during the Devonian period, disappeared before the close of the Carboniferous.

About 700 species of Carboniferous fish have been described largely from teeth, spines and dermal ossicles.

The fossil plants which are found in the upper beds of the preceding Devonian system are so closely related to those in the Lower Carboniferous, that from a palaeobotanical standpoint the two form one indivisible period.

In the Lower Carboniferous the flora was composed of six great groups of plants, viz.

These six groups were the dominant types throughout the period, but during Upper Carboniferous time three other groups arose, the Coniferales, the Cycadophyta, and the Ginkgoales (of which Ginkgo biloba is the only modern representative).

The fronds of some of these Carboniferous ferns are almost identical with those of living species.

Our modern diminutive " horsetails " with scaly leaves were represented in the Carboniferous period by gigantic calamites, often with a diameter of I to 2 ft.

The Carboniferous forerunners of the tiny club-moss were then great trees with dichotomously branching stems and crowded linear leaves, such as Lepidodendron (with its fruit cone called Lepidostrobus), Halonia, Lepidophloios and Sigillaria, the largest plants of the period, with trunks sometimes 5 ft.

The animals preserved in the continental type of Carboniferous deposit naturally differ markedly from the fossil remains of the purely marine portions of the system.

In the later Carboniferous rocks the earliest amphibians make their appearance in considerable numbers; they were all Stegocephalians (Labyrinthodonts) with long bodies, a head covered with bony plates and weak or undeveloped limbs.

In western Europe the advent of the Carboniferous period was accompanied by the production of a series of synclines which permitted the formation of organic limestones, free from the sediments which generally characterized the concluding phases of the preceding Devonian deposition.

Thus western Europe in early Carboniferous time was occupied by a series of constricted, gulf-like seas; and on account of the steady progress of intermittent warping movements of the crust, we find that the areas of clearer water, in which the limestone-building organisms could exist, were repeatedly able to spread, thus forming those thin limestones found interbedded with shale and sandstone which occur typically in the Yoredale district of Yorkshire and in the region to the north, and also in the culm deposits of central Europe.

Farther south in the Donetz basin the coals only appear at the close of the Lower Carboniferous.

The close of the early Carboniferous period was marked by an augmentation of the orogenic movements.

This movement commenced in the central and western part of the continent and continued throughout the whole Carboniferous period.

The sea had gained somewhat at the beginning of the Carboniferous period in western Europe, but the effect of these movements, combined with the rapid formation of detrital deposits from the rising land areas, was to drive the sea steadily from the north towards the south, until the open sea (with limestones) was relegated to what is now the Mediterranean and to Russia and thence eastward.

In the Lower Carboniferous rocks of Scotland intercalated volcanic rocks are strikingly abundant, and now form an important feature in the geology of the southern portion of that country.

Porphyrites and tuffs are known in the French Carboniferous.

In North America, the principal region of volcanic activity lay in the west; great thicknesses of igneous rocks occur in the Lower Carboniferous rocks of British Columbia, and from the middle of the period until near its close volcanoes were active from Alaska to California.

Carbon dioxide may have been present in the air in greater abundance in earlier periods than it is at present, but there is no reason to suppose that the percentage was appreciably higher in the Carboniferous period than it is now.

The abundance of corals in some of the Carboniferous seas and possibly also the large size of some of the Productids and foraminifera may be taken as evidence of warm or temperate waters.

Glacial deposits certainly do exist in the Permo-carboniferous formations, which are described under that head, but in the true Carboniferous system glaciation may be taken as not proven.

Oil and gas are of importance in the Lower Carboniferous Pocono sandstone of West Virginia and in the Berea grit of Ohio, where brine also occurs.

In the Carboniferous Limestone series, the purer kinds of limestone are used for the manufacture of lime, bleaching powder and similar products, also as a flux in the smelting of iron; some of the less pure varieties are used in making cement.

Within the Carboniferous rocks, but due to the action of various agencies long after their deposition, are important ore formations; such are the Rio Tinto ores of Spain, the lead and zinc ores and some haematite of the Pennine and Mendip hills and other British localities, and many ore regions in the United States.

They probably belong to several geological periods, but all were folded and denuded before the Carboniferous beds were deposited.

It lies unconformably upon the older rocks; and the limestone contains Fusulina, Phillipsia and Productus, indicating that it belongs to the Upper Carboniferous.

They rest unconformably upon the Carboniferous beds, and have themselves been tilted to a steep angle.

They extend back beyond the Carboniferous, where they occur as hyphae, &c., preserved in the fossil woods, but the best specimens are probably those in amber and in siliceous petrifactions of more recent origin.

The cost of iron ore is likely to rise much less rapidly than that of coal, because the additions to our known supply are likely to be very much greater in the case of ore than in that of coal, for the reason that, while rich and great iron ore beds may exist anywhere, those of coal are confined chiefly to the Carboniferous formation, a fact which has led to the systematic survey and measurement of this formation in most countries.

Besides parts of the carboniferous measures of the Saar and the Ruhr, it also contains important deposits of coal near Aix-la-Chapelle.

The latest beds which are involved in the folds of this mountain range belong to the Coal Measures, and the final elevation must have taken place towards the close of the Carboniferous period.

Carboniferous beds occur in the north of the Palaeozoic area.

The hills and plateaus appear to be composed chiefly of the same sandstone series which in the Brazilian province of Rio Grande do Sul contains seams of coal, with plant remains similar to those of the Karharbari series of India (Permian or Upper Carboniferous).

Carboniferous and Devonian beds are also found south-east of the Bohemian massif, where lies the extensive coal-field of Silesia.

He also described the fossil plants of the Silurian, Devonian and Carboniferous rocks of Canada for the Geological Survey of that country (1871-1873).

Some of the salt of Michigan is regarded as Carboniferous.

Considering, however, that it is generally believed that Bryophyta and vascular plants are descended from an algal ancestry, it is natural to suppose that, prior to the luxuriant vegetable growths of the Carboniferous period, there must have existed an age of algae.

There is a central region, roughly triangular in shape, with its base resting upon the Quaternary K Triassic Tertiary Carboniferous q & Metamorphic 7 Jurassic Aegean Sea and its apex in Servia.

In the north, Carboniferous beds are present, and the Trias and the Jura take a considerable part in the formation of the chain.

The southern edge of the county is formed by the scarps and moorlands of the Carboniferous Limestone and Millstone Grit (both of which form also the outlier of Pen-ceryg-calch north of Crickhowell), while the lowest beds of the Coal Measures of the South Wales coalfield are reached in the Tawe and Neath valleys (where the beds are much folded) and near Tredegar and Brynmawr.

These are covered by the successive formations of the Carboniferous system.

In other words, the Old Red Sandstone and Carboniferous rocks, though chiefly accumulated in the broad lowland valley, crept also over some part of the hills on either side, where a few outliers tell of their former extension.

The Carboniferous lavas of the Campsie and Fintry Hills and of the south of Dumfriesshire and Roxburghshire likewise rise in lines of bold escarpment.

The areas occupied by Carboniferous rocks are almost entirely restricted to the Central Plain or Lowlands, but they are also found skirting the Southern Uplands from the mouth of the Tweed to that of the Nith.

The coal-fields contain two main groups of seams, the lower in the middle section of the Carboniferous Limestone, and the upper in the Coal Measures.

The plant-life of the Carboniferous was exceedingly luxuriant and varied, and the system is rich also in fossils of fishes, crustaceans, mollusca, insects and other forms of animal life.

There was great volcanic activity during the deposition of the Calciferous Sandstone, Carboniferous Limestone and Millstone Grit series.

Most of the hills and crags in the Carboniferous area are volcanic, and many of them - such as the castle rocks of Edinburgh and Stirling, Binny Craig in Linlithgowshire, North Berwick Law and the Bass Rock - mark the sites of actual events of eruption.

The mineral is chiefly obtained from seams in the Calciferous Sandstone at the base of the Carboniferous rocks.

The fossils include Syringopora, Zaphrentis, Productus, Spirifer, &c., and belong to the Carboniferous.

The sandstone which lies below the limestone is also, no doubt, of Carboniferous age; but the sandstone above is conformably overlaid by Upper Cretaceous beds and is generally referred to the Lower Cretaceous.

No unconformity, however, has yet been detected anywhere in the sandstone series, and in the absence of fossils the upper sandstone may represent any period from the Carboniferous to the Cretaceous.

The lowest beds of this series, which from their position may belong either to the Permian or to the upper part of the Carboniferous, have yielded no recognizable fossils; but they include a conglomerate which closely resembles the boulder bed near the base of the Talchir series in India.

The former, from the Tertiary period even to the present day, has been -a region of compression; the latter, since the Carboniferous period at least, has been a region of equilibrium or of tension.

Carboniferous beds, consisting chiefly of slates, sandstones and conglomerates, are found in the south-eastern provinces.

The Carboniferous rocks of Arran include representatives of the Calciferous Sandstone, the three subdivisions of the Carboniferous Limestone series, and to a small extent the Coal Measures, and are confined to the north part of the island.

Here there is an ascending sequence from the Calciferous Sandstone, through the Carboniferous Limestone with thin coals formerly worked, to the Coal Measures, the strata being inclined at high angles to the north.

On the south side of a well-marked anticline in the Upper Old Red Sandstone at North Sannox, the Carboniferous strata reappear on the coast with a south dip showing a similar ascending sequence for about half a mile.

The small development of Upper Carboniferous strata, visible on the shore south of Corrie and in Ben Lister Glen, consists of sandstones, red and mottled clays and purple shales, which yield plantremains of Upper Carboniferous facies.

Contemporaneous volcanic rocks, belonging to three stages of the Carboniferous formation, occur in Arran.

The second is represented by a thin lava, associated with the Upper Limestone group of the Carboniferous Limestone series, and the highest is found in Ben Lister Glen intercalated with the Upper Carboniferous strata, and may be the equivalent of the volcanic series which, in Ayrshire, occupies the position of the Millstone Grit.

At Corrie and the Cock of Arran they rest on Upper Carboniferous strata; in Ben Lister Glen, on the lower limestone group of the Carboniferous Limestone series; and on the west coast they repose on the Old Red Sandstone.

Vertebraria and Phyllotheca, plants characteristic of the Indian Gondwana series, have been recorded in Sarawak; and marine forms, similar to those of the lower part of the Australian Carboniferous system, are stated to occur in the limestone of north Borneo.

Until the fourth decade of the 19th century all stratified rocks older than the Carboniferous had been grouped by geologists into a huge and indefinite "Transition Series."

Devonian and Carboniferous fossils have been found in several places in the Anti-Taurus.

Carboniferous rocks occur at Eregli (Heraclea Pontica), where they have been worked for coal.

Devonian fossils have been found near the Bosporus and Carboniferous fossils at Balia Maden in Mysia.

Cambrian, Silurian, Devonian and Carboniferous deposits are found on the coasts of the Gulf of Finland and Lake Ladoga, and also along the coasts of the Arctic Ocean (probably Devonian), and in the Kjolen.

In the peninsula, however, no marine fossils have yet been found of earlier date than J urassic and Cretaceous, and these are confined to the neighbourhood of the coasts; the principal fossiliferous deposits are the plantbearing beds of the Gondwana series, and there can he no doubt that, at least since the Carboniferous period, nearly the whole of the Peninsula has been land.

From these beds up to the top of the Carboniferous there appears to be no break; but the Carboniferous beds were in some places eroded before the deposition of the Productus shales, which belong to the Permian period.

It is, however, possible that this erosion was merely local, for in other places there seems to be a complete passage from the Carboniferous to the Permian.

The Lower Carboniferous, which belongs to the " Culm " facies so widely spread in central Europe, occupies a wide area in southern Portugal; but the Upper Carboniferous is very restricted in extent, and occurs in small basins like those of the Central Plateau of France, resting unconformably upon the rocks below.

The Palaeozoic beds have yielded fossils of Cambrian, Ordovician, Devonian and Carboniferous age.

In southern Bolivia Cambrian and Ordovician beds form the greater part of the eastern Andes, but farther north the, Devonian and Carboniferous are extensively developed, especially in the northeastern ranges.

That bacteria have existed from very early periods is clear from their presence in fossils; and although we cannot accept all the conclusions drawn from the imperfect records of the rocks, and may dismiss as absurd the statements that geologically immured forms have been found still living, the researches of Renault and van Tieghem have shown pretty clearly that large numbers of bacteria existed in Carboniferous and Devonian times, and probably earlier.

In the first part of its course, which may be said to end at Dorogobuzh, it flows through an undulating country of Carboniferous formation; in the second it passes west to Orsha, south through the fertile plain of Chernigov and Kiev, and then southeast across the rocky steppe of the Ukraine to Ekaterinoslay.

Some of the finest crystals occur in the lead-veins of the Carboniferous Limestone series in the north of England, especially at Weardale, Allendale and Alston Moor.

The Russian Altai is composed mainly of mica and chlorite schists and slates, together with beds of limestone, and in the higher horizons Devonian and Carboniferous fossils occur in many places.

In England valuable deposits occur in the Carboniferous Limestone of west Cumberland (Whitehaven district) and north Lancashire (Ulverston district).

The Devonian system is separated from the Carboniferous by an interval, during which there were powerful earth movements; they produced a lofty mountain chain, running north and south across New South Wales.

In Lower Carboniferous times these mountains were snow-capped, and the valleys on their flanks were occupied by glaciers.

The Lower Carboniferous beds are represented by conglomerates and sandstones with some shales and limestones.

The Lower Carboniferous rocks also occur in the Blue Mountains, along the Cox river and Capertee river; and a northern continuation occurs along the western slope of the New England tableland, from the Macintyre river to the Queensland border.

The Upper Carboniferous rocks are most important from their rich seams of coal.

The Carboniferous beds contain numerous sheets and flows of basalt and andesite.

A syenite massif of this age occurs at Mittagong; and leucite has been discovered in Carboniferous basalts by David.

The recent discovery in the Tasmanian " schizopod " Anaspides, of what is believed to be a living representative of the Carboniferous and Permian Syncarida, has, however, afforded a clue to the affinities of some of these problematical forms.

The Western Division is composed entirely of Archaean and Palaeozoic rocks, embracing the whole range from pre-Cambrian up to Carboniferous.

Round these central masses of early Palaeozoic rocks there is a broken ring of Carboniferous Limestone, and several patches of Coal Measures, while the New Red Sandstone appears as a boundary belt outside the greater part of the district.

Where the Coal Measures reach the sea at Whitehaven, there are coal-mines, and the hematite of the Carboniferous Limestones has given rise to the active ironworks of Barrow-in-Furness, now the largest town in the district.

The region is entirely composed of Carboniferous rocks, the system which transcends all others in the value of its economic minerals.

The whole region may be looked upon as formed by an arch or anticline of Carboniferous strata, the axis of which runs north and south; the centre has been worn away by erosion, so that the Coal Measures have been removed, and the underlying Millstone Grit and Carboniferous Limestone exposed to the influences which form scenery.

Crossfell and the neighbouring hills are formed from masses of Carboniferous Limestone, which received its popular name of Mountain Limestone from this fact.

Compared with the rugged and picturesque scenery of the Lower Carboniferous rocks, that of the Coal Measures is, as a rule, featureless and monotonous.

The group of heights of South Wales, running on the whole from west to east, marks the outcrops of the Old Red Sandstone and Carboniferous strata which lie within a vast syncline of the Silurian rocks.

The Brecon Beacons of Old Red Sandstone are the highest (2907 ft.), but the Black Mountain bears a number of picturesque summits carved out of Millstone Grit and Carboniferous Limestone, which rise frequently over 2000 ft.

The outer rim of the Welsh area contains a broken series of coal-fields, where patches of Carboniferous strata come to the surface on the edge of the New Red Sandstone plain.

The great coal-field on the south is a perfect example of a synclinal basin, the Millstone Grit and Carboniferous Limestone which underlie the Coal Measures appearing all round the margin.

The peninsula of Cornwall and Devon may be looked upon as formed from a synclinal trough of Devonian rocks, which appear as plateaus on the north and south, while the centre is occupied by Lower Carboniferous strata at a lower level.

The Carboniferous rocks of the centre form a soil which produces rich pasture under the heavy rainfall and remarkably mild and equable temperature, forming a great cattle-raising district.

One such outcrop of Carboniferous Limestone in the south forms the Mendip Hills; another of the Coal Measures increases the importance of Bristol, where it stands at the head of navigation on the southern Avon.

Its central core of Lower Carboniferous rock is broadly displayed towards the north, while southward it contracts; on either side lie the younger rocks, the coal-fields, the Permian strata and the Triassic formations, the last-named, while sweeping round the southern extremity of the Carboniferous axis of the uplift from its eastern and western flanks, spread out in a large sheet over the midland counties.

This condition led up to the Carboniferous period, which began with fairly open sea over the south and north of England, but in the centre there rose an elevated land mass from which much of the Millstone Grit was derived; other land lay towards the north.

It was about this time that the Pennine Hills, the Lake District mountain mass, and the Mendip Hills were being most vigorously uplifted, while the granite masses of Cornwall and Devon wore perhaps being injected into the Carboniferous and Devonian rocks.

The volcanic outbursts which followed became feebler in the Devonian and Carboniferous periods and ceased with the Permian.

Pedipalpi date back to the Carboniferous Period, occurring in deposits of that age both in Europe and North America.

The geological history of the state covers the period from Algonkian to late Carboniferous time, after which there is a gap in the record until Tertiary time, except that there was apparently a temporary depression of the north-western and southwestern corners in the Cretaceous age.

Regarding now the outcrops of bed-rock, there are exposures of Algonkian (doubtful, and at most a mere patch on Pilot Knob), Archean, Cambrian, Ordovician, Silurian, Devonian, sub-Carboniferous and Carboniferous.

Next, covering the north-eastern and south-western corners of the state, and connecting them with a narrow belt, are the lower Carboniferous measures (which also appear in a very narrow band along the Mississippi for some distance below St Louis).

Boo Jurassic 4000 1400 2000 Trias 5000 Permian 2600 600 Carboniferous woo 700 Series Beaufort Series Ecca Series Dwyka Series the eastern coast-lands the vegetation becomes distinctly subtropical.

Part of the rock is schist, but the greater portion limestone, similar in physical qualities to the Carboniferous limestone of Great Britain.

As for Holothuroidea, the fossil evidence allows us to say no more than that the class existed in early Carboniferous times, if not before.

The Silurian, Devonian and Carboniferous systems are represented - the Silurian and Devonian forming the greater part of the hills S.E.

A few patches of Upper Carboniferous are found on the borders of the hills near Ilfeld, Ballenstedt, &c., lying unconformably upon the Devonian.

Metalliferous veins are common, amongst the best-known being the silver-bearing lead veins of Klausthal, which occur in the Culm or Lower Carboniferous.

It is only in the outer foldings of the highlands that Palaeozoic fossiliferous deposits are found - Silurian, Devonian, Carboniferous and Permo-Carboniferous.

While upheavals having a north-eastern strike continued to take place after the Carboniferous epoch,' another series of upheavals, having a north-western strike, and occasioned by the expansion of diabases, dolerites, melaphyres and andesites, occurred later, subsequently at least to the close of the Tertiary period, if not also before it, dislocating former chains and raising rocks to the highest levels by the addition of new upheavals to the older ones.

The two most important points of contrast between the geology of Ireland and that of England are, firstly, the great exposure of `Carboniferous rocks in Ireland, Mesozoic strata being almost absent; and, secondly, the presence of volcanic rocks in place of the marine Eocene of England.

They come out as mica-schists under the Carboniferous sandstones of northern Antrim, and disappear southward under the basaltic plateaux.

All across Ireland, from the Ballyhoura Hills on the Cork border to the southern shore of Belfast Lough, slaty and sandy Silurian beds appear in the axes of the anticlinal folds, surrounded by Old Red Sandstone scarps or Carboniferous Limestone lowlands.

The Yellow Sandstone contains Archanodon, the oldest known fresh-water mollusc, and plant-remains; the Coomhola Grits are marine, and are sometimes regarded as Carboniferous, sometimes as uppermost Devonian.

In the south, the Carboniferous deposits open with the Carboniferous Slate, in the base of which the Coomhola Grits occur.

Its lower part represents the Lower Carboniferous Shales and Sandstones of the central and northern areas, while its upper part corresponds with a portion of the Carboniferous Limestone.

The Carboniferous Limestone, laid down in a sea which covered nearly the whole Irish area, appears in the synclinal folds at Cork city and Kenmare, and is the prevalent rock from the north side of the Knockmealdown Mountains to Enniskillen and Donegal Bay.

The Lower Carboniferous Sandstones are conspicuous in the region from Milltown near Inver Bay in southern Donegal to Ballycastle in county Antrim.

In the latter place they contain workable coal-seams. The Carboniferous Limestone often contains black flint (chert), and at some horizons conglomerates occur, the pebbles being derived from the unconformable ridges of the " Caledonian " land.

The "Hercynian " earth-movements, which so profoundly affected north-west and north-central Europe at the close of Carboniferous times, gave rise to a series of east and west folds in the Irish region.

The Upper Carboniferous beds were thus lifted within eas3r.

In the south, even the Carboniferous Limestone has been so far removed that it is found only in the floors of the synclinals.

The Triassic beds rest on the various Carboniferous series in turn, indicating, as in England, the amount of denudation that followed on the uplift of the Hercynian' land.

Probably its original thickness Lough Neagh Tertiary Clays Eocene Basalt and Dolerite Cretaceous Trias, sometimes surmounted by Lower Jurassic Upper Carboniferous Carboniferous was not more than 150 ft., while now only from 40 to loo ft.

In Bohemia and Moravia the whole of the beds from the Cambrian to the Lower Carboniferous are of marine origin; but after the Carboniferous period the area appears to have been dry land until the beginning of the Upper Cretaceous period, when the sea again spread over it.

The Carboniferous coal-fields of Silesia and Bohemia are of the greatest importance; while Jurassic coal is worked at Steyerdorf and Ftinfkirchen in Hungary, and lignite at many places in the Tertiary beds.

In both a successive series of continental deposits, ranging from the Carboniferous to the Rhaetic, rests on an older base of crystalline rocks.

The Devonian and Carboniferous formations are well represented in the north and south and in northern Angola.

In late Carboniferous times Africa and India were undoubtedly united to form a large continent, called by Suess Gondwana Land.

During the whole of the time - Carboniferous to Rhaetic - that this great accumulation of freshwater beds was taking place, the interior of the continent must have been undergoing depression.

The Lower Carboniferous rocks of Spain consist partly of limestones, and partly of shales, sandstones and conglomerates like the culin of Devonshire.

The Upper Carboniferous is formed to a large extent of sandstones and shales, with seams of coal; but beds of massiye limestones are often intercalated, and some of these contain Fusaljna and other fossils like those of the Russian Ftisulina limestone.

The Palaeozoic era is represented only by the Pennsylvanian series of the Upper Carboniferous and a scanty strip of Kansas-Nebraska Permian, and is confined to the S.E.

But, though small in area, the Carboniferous is by far the most important formation as regards mineral resources within the state.

The quarries and clay pits of the state are mainly in the Carboniferous region of the S.E.

The Carboniferous formations carry only thin seams of coal, never thicker than about 2 ft., and rarely readily accessible, and they can never be of more than small and merely local importance.

The geological sequence in Tasmania is full, and the island contains a better series of Carboniferous rocks than is found in Victoria.

The Carboniferous system begins with a series of marine limestones, shales and grits, including a rich Lower Carboniferous fauna.

The Carboniferous rocks occupy the whole of the south-eastern corner of Tasmania; and one outlier occurs on the northern coast in the Mersey Valley.

The Upper Carboniferous includes beds of shale and coal; but though the coal is good, the seams are thin and have not been much worked.

The Coal Measures are covered by marine shales with numerous bryozoa; and, on the horizon of the Greta Coal Measures of New South Wales, is a bed of Carboniferous glacial deposits.

The tinguaites and solvsbergites of Port C y gnet, south of Hobart, may be of this age; they are intrusive in Carboniferous rocks, and there is no evidence of their precise date; but their resemblance to the rocks associated with the geburite-dacite of Victoria suggests that they may belong to.

All the geological systems,from the Cambrian to the Carboniferous, are represented and they are all strongly folded, the folds leaning over towards the west.

Calcified specimens are especially characteristic of the British Carboniferous formation; their preservation is equally perfect with that of the silicified fossils, and their investigation by Witham, Binney, Williamson and others has proved no less fertile.

A branched filamentous organism from the Lower Carboniferous of Scotland, described by Kidston under the name of Bythotrephis worstoniensis, shows some remains of cellular structure, and may probably be a true Alga, resembling some of the filamentous Florideae in habit.

Weiss has obtained interesting evidence that the symbiotic association between roots and Fungi, known as " Mycorhiza," already occurred among Carboniferous plants.

In the Lower Carboniferous of Scotland Mr Kidston has found several specimens of a large dichotomous thallus, with a very distinct midrib; the specimens, referred to the provisional genus Thallites, much resemble the larger thalloid Liverworts.

They extend back through the Devonian, possibly to the Silurian system, but the systematic summary now to be given is based primarily on the rich materials afforded by the Carboniferous and Permian formations, from which our detailed knowledge of Palaeozoic plants has been chiefly derived.

In the oldest known Calamarian, however, Archaeocalamites (Devonian and Lower Carboniferous), the leaves were repeatedly forked.

Archaeocalamites appears to have had a similar structure, but in some specimens from the Lower Carboniferous of Burntisland, provisionally named Protocalamites pettycurensis, centripetal wood was present in the stem.

In the Lower Carboniferous of central Russia beds of coal occur consisting of the cuticles of a Bothrodendron, which are not fossilized, but retain the consistency and chemical composition of similar tissues in recent plants.

The anatomy of Lepidodendron and its immediate allies is now well known in a number of species; the Carboniferous rocks of Great Britain are especially rich in petrified specimens, which formed the subject of Williamson's extensive investigations.

A more important deviation from ordinary Lepidostroboid structure is shown by the genus Lepidocarpon, from the English Coal Measures and the Lower Carboniferous of Scotland.

Generally, the Eusigillariae are characteristic of the older Carboniferous strata, the Subsigillariae of the Upper Coal Measures and Permian.

Numerous more or less isolated fern-sporangia occur in the petrified material of the Carboniferous formation; the presence of an annulus is a frequent character among these specimens, while synangic sori are rare; it is thus certain that families remote from the Marattiaceae were abundantly represented during this period.

The type-genus Botryopteris, represented in the Permo-Carboniferous of France and in both the Lower and Upper Carboniferous of Great Britain, had a rhizome, with a very simple monostelic structure, bearing spirally arranged compound leaves, with lobed pinnules, probably of a somewhat fleshy texture.

The genus Zygopteris, of which numerous Carboniferous and Permian species are known, likewise had a monostelic stem, but the structure of its vascular cylinder was somewhat complex, resembling that of the most highly differentiated Hymenophyllaceae, with which some species of Zygopteris also agreed in the presence of axillary shoots.

The family Calamopityeae, allied anatomically to Lyginodendreae, is of Devonian and Lower Carboniferous age.

Corresponding strands of primary xylem have been observed in stems of the genus Pitys (Witham), of Lower Carboniferous age, which consisted of large trees, probably closely allied to Cordaites.

Isolated fossil seeds are common in the Carboniferous and Permian strata; in all cases they are of the orthotropous type, and resemble the seeds of Cycads or Ginkgo more nearly than those of any other living plants.

Our knowledge of vegetation older than the Carboniferous is still far too scanty for any satisfactory history of the Palaeozoic Floras to be even attempted; a few, however, of the facts may be advantageously recapitulated in chronological order.

The evidence for terrestrial Silurian vegetation is still dubious; apart from some obscure North American specimens, the true nature of which is not established, Potonie has described well-characterized Pteridophytes (such as the fern-like Sphenopteridium and Bothrodendron among Lycopods) from supposed Silurian strata in North Germany; the horizon, however, appears to be open to much doubt, and the specimens agree so nearly with some from the Lower Carboniferous as to render their Silurian age difficult of credence.

Even in the Lower Devonian, Ferns and Lepidodendreae have been recognized; the Middle and Upper Devonian beds contain a flora in which all the chief groups of Carboniferous plants are already represented.

Any detailed account of the horizons of Carboniferous plants would carry us much too far.

For our present purpose we may divide the formation into Lower Carboniferous and Lower and Upper Coal Measures.

In the Lower Carboniferous (Culm of Continental authors) many Devonian types survive - e.g.

Many specimens with structure preserved are known from the Lower Carboniferous, and among them Pteridosperms (Heterangium, Calamopitys, Cladoxylon, Protopitys) are well represented, if we may judge by the anatomical characters.

During the earlier part of the Carboniferous epoch the vegetation of the world appears to have been remarkably uniform; while the deposition of the Coal Measures, however, was in progress, a differentiation of floral regions began.

In the succeeding Permian period the vegetation retained for the most part the same general character; some of the Carboniferous genera died out, and a few new types made their appearance.

The Upper Carboniferous and Permian plants may be grouped together as constituting a Permo-Carboniferous flora characterized by an abundance of arborescent Vascular Cryptogams and of an extinct class of plants to which the name Pteridosperms has recently been assigned - plants exhibiting a combination of Cycadean and filicinean characters and distinguished by the production of true gymnospermous seeds of a complex type.

In Australia, South America and South Africa a few plants have been found which agree closely with Lower Carboniferous types of the northern hemisphere.

In New South Wales, for example, we have such genera as Rhacopteris and Lepidodendron represented by species very similar to those recorded from Lower Carboniferous or Culm rocks in Germany, Austria, England, Spitzbergen, North and South America and elsewhere.

It is, in short, clear that the Culm flora, as we know it in the northern hemisphere, existed in the extreme south, and it is probable that during the earlier part of the Carboniferous period the vegetation of the world was uniform in character.

From strata in New South Wales overlying Devonian and Lower Carboniferous rocks certain plants were discovered in the early part of the 19th century which were compared with European Jurassic genera, and for several years it was believed that these plant-beds belonged to the Mesozoic period.

The extraordinary abundance of Glossopteris in PermoCarboniferous rocks of Australia, and in strata of the same age in India and South Africa, gave rise to the term " Glossopteris flora for the assemblage of plants obtained from southern hemisphere rocks overlying beds containing Devonian and Lower Carboniferous fossils.

The most important evidence on which this conclusion is based is afforded by the occurrence of European forms of Carboniferous shells in marine strata in New South Wales, which are intercalated between Coal Measures containing members of the Glossopteris flora, and.

This flora appears to have abruptly succeeded an older flora in Australia and elsewhere, which was precisely similar to that of Lower Carboniferous age in the northern hemisphere.

On the other hand, the plant-beds of the Permo-Carboniferous age in South Africa, South America, India and Australia demonstrate the existence of a widely distributed vegetation wh i ch agrees in age with the Upper Carboniferous and of the beds in which Glossopteris and other genera make FIG.

Phyllotheca has been recognized in Europe in strata of Palaeozoic age, and Professor Zeiller has discovered a new species - P. Rallii- in Upper Carboniferous rocks in Asia Minor (Map A, VII.), which points to a close agreement between this genus and the well-known Palaeozoic Annularia.

While a few similar or even identical types may be recognized in both floras, there can be no doubt that, during a considerable period subsequent to that represented by the Lower Carboniferous or Culm rocks, there existed two distinct floras, one of which had its headquarters in the northern hemisphere, while the other flourished in a vast continental area in the south.

The Permo - Carboniferous beds of South Africa, India and Australia are succeeded by other plant-bearing strata, containing numerous species agreeing closely with members of the Rhaetic and Jurassic floras of the northern hemisphere.

A few plants described by Potonie from German and Portuguese East Africa demonstrate the occurrence of Glossopteris and a few other genera, referred to a Permo-Triassic horizon, in a region slightly to the north of Tete in the Zambesi district (Map A, I.), where typical European plants agreeing with Upper Carboniferous types were discovered several years ago, and described by Zeiller in 1882 and 1901.

The latter genus ranges from Upper Carboniferous to Jurassic rocks; it occurs in India, Australia, and elsewhere in the " Gondwana Land " vegetation, as well as in Palaeozoic rocks of Asia Minor, in Permian rocks of Siberia, and in Jurassic plant-beds of Italy.

In the southern hemisphere the Glossopteris flora succeeded a Lower Carboniferous vegetation with a rapidity similar to that which marked the passage in the north from Palaeozoic to Mesozoic floras.

Over 200 species are now distinguished, from the Carboniferous of Europe and North America, the Permian of Spitsbergen, Europe, North America and South Africa, and the Trias of Europe, America, South Africa, India and Australia.

Many of the clays which pass under this designation belong to the Carboniferous period, and are found underlying seams of coal.

Laminated clays of this sort are generally known as shales; they occur in many formations but are very common in the Carboniferous.

These occur over an area of Carboniferous limestone bedrock.

Cathodoluminescence micrograph of zoned calcite cement in thin section, Pwll y Cwm Oolite, Lower Carboniferous, Baltic Quarry, South Wales.

The conglomerate is in turn overlain by Carboniferous limestone.

South of the Clougher Valley the carboniferous limestones have sandstone deposited on top with beds of shale contained in the sandstones.

In contrast the southern North Sea gas province has been charged almost entirely from the Carboniferous Coal Measures.