Cretaceous Sentence Examples

The latest Cretaceous is the Ripley formation, which lies west of the northern part of the last-named, and, about Scooba, in a small strip, the most southerly of the Cretaceous - it is composed of coarse sandstones, hard crystalline white limestones, clays, sands, phosphatic greensands, and darkcoloured, micaceous, glauconitic marls; its greatest thickness is about 280 ft.

Deposits of the Tertiary period form the basis of more than half the state, extending from the border of the Cretaceous westward nearly to the Yazoo Delta and the Mississippi Bottom, and southward to within a few miles of the Gulf coast.

The high land in the west of the island and the somewhat less elevated region in the east are formed of Upper Tithonian and Lower Cretaceous limestones, the latter containing Rudistes.

The greater part of western Asia, including the basin of the Obi, the drainage area of the Aral Sea, together with Afghanistan, Baluchistan, Persia and Arabia, was covered by the sea during the later stages of the Cretaceous period; but a considerable part 3f this region was probably dry land in Jurassic times.

Excepting in the extreme north, where marine Jurassic and Cretaceous fossils have been found, there is no evidence that this part of Siberia has been beneath the sea since the early part of the Palaeozoic era.

The sea in which these strata were deposited seems to have attained its greatest extension in Upper Cretaceous times, when its waters spread over the whole of western Asia and even encroached slightly upon the Indian land.

Leaving out of consideration all evidence of more ancient volcanic activity, each of the three regions, into which, as we have seen, the continent may be divided, has been, during or since the Cretaceous period, the seat of great volcanic eruptions.

C. Marsh, by finding the imperfect fossilized tibia of a bird in the middle cretaceous shale of Kansas, Marsh, began a series of wonderful discoveries of great im portance to ornithology.

Towards the Caspian, especially between Petrovsk and the river Sulak, the Cretaceous system is well represented, and upon its rocks rest marls, shales, and sandstones of the Eocene period.

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.

Cretaceous limestones cover the greater part of Palestine and rocks of the same period form Mt Lebanon, the Casius Mons, &c., farther north.

Nummulitic limestone (Eocene) overlies the Cretaceous in Philistia, and north of Lebanon Eocene and Miocene deposits cover the greater part of the country.

The faulting which formed the depressions is certainly later than the deposition of the Cretaceous beds and probably belongs to the later portion of the Tertiary era.

The coal belongs to the Cretaceous beds, and while not so heavy as that of the Coal Measures is of excellent quality.

Fossiliferous Cretaceous limestones containing Rudistes have been found in several parts of the island (Santiago de los Banos, Santa Clara province, &c.).

Along the west frontier there appear broad and strongly marked zones of Cretaceous limestone, alternating with Jurassic and Triassic, joined by a strip of Palaeozoic formations running from the north-west corner of Bosnia.

These beds, as well as the Cretaceous series, from which they are as yet only imperfectly distinguished, are associated with sheets of basalt, which penetrate them in great dikes, and in some places, owing to the wearing away of the softer sedimentary rocks, stand out in long walls running across the beds.

The only Mesozoic system which is represented in Brazil by marine beds is the Cretaceous, and the marine facies, is restricted to the coasts and the basin of the Amazon.

In the province of Sergipe, on the east coast, the beds are approximately on the horizon of the Cenomanian; in the valley of the Amazon they belong to the highest parts of the Cretaceous system, and the fauna shows Tertiary affinities.

They are exceedingly prolific in fossils which prove them to be of Upper Cretaceous age.

These are composed chiefly of Triassic beds, but Jurassic and Cretaceous beds take some share in their formation.

They may be of Cretaceous age or even later, and in any case belong to the same class as those of Kimberley.

In the latter range a few Ordovician fossils have been found, but in general the oldest strata which have yielded organic remains belong to the Cretaceous system.

The Cretaceous beds form a band along each side of the Cordillera and along the southern flank of the Caribbean chain, and they spread over the greater part of the provinces of Falcon and Lara.

There is considerable difference of opinion as to the chronology of the succeeding beds, and the boundary between the Cretaceous and Tertiary systems is drawn at various horizons by different observers.

Its upheaval above the great sea which submerged all the north-west of the Indian peninsula long after the Himalaya had massed itself as a formidable mountain chain, belongs to a comparatively recent geologic period, and the same thrust upwards of vast masses of cretaceous limestone has disturbed the overlying recent beds of shale and clays with very similar results to those which have left so marked an impress on the Baluch frontier.

There is an axial zone of Cretaceous and Lower Eocene, and this is flanked on each side by the Upper Eocene and the Miocene, while the valley of the Irrawaddy is occupied chiefly by the Pliocene.

The Cretaceous beds have not yet been separated from the overlying Eocene, and the identification of the system rests on the discovery of a single Cenomanian ammonite.

The geological formation of the soil belongs to the Quaternary and Pliocene period in its upper strata, and to the Eocene and Cretaceous in the lower.

Pietra forte of the Cretaceous period is quarried north and south of the city, and has been used for centuries as paving stone and for the buildings.

They are covered by marine Jurassic beds and they in turn by Cretaceous coal-bearing, terrestrial deposits, resembling those of New Zealand.

Upon the sandstone rest a few scattered outliers of limestone, probably of Cretaceous age, the largest of which occur near Jauf and east of Bureda.

Generally, however, the Cretaceous beds do not appear, and the greater part of southern Arabia seems to be formed of Alveolina and nummulite limestones of Tertiary age.

Lower Cretaceous rocks, consisting of thick limestones, shales and marls, occur in Central Tunisia.

The fossils show many notable affinities with those in the Lower Cretaceous of the Pyrenees.

Geology.'--The Eastern Cordillera., which, however, is but little known, appears to consist, as in Bolivia, chiefly of Palaeozoic rocks; the western ranges of the Andes are formed of Mesozoic beds, together with recent volcanic lavas and ashes; and the lower hills near the coast are composed of granite, syenite and other crystalline rocks, sometimes accompanied by limestones and sandstones, which are probably of Lower Cretaceous age, and often covered by marine Tertiary deposits.

From the analogy of the neighbouring countries it is possible that some of the tuffs may be Jurassic, but the other deposits probably belong for the most part to the Cretaceous system.

The Cyclostomata are numerous in Palaeozoic rocks, but attained a specially predominant position in the Cretaceous strata, where they are represented by a prpfusion of genera and species; while they still survive in considerable numbers at the present day.

As indications that the conditions described in Membranipora and Cribrilina are of special significance may be noted the fact that the ancestrula of many genera which have well-developed compensation-sacs in the rest of their zooecia is a Membranipora-like individual with a series of marginal calcareous spines, and the further fact that a considerable proportion of the Cretaceous Cheilostomes belong either to the Membraniporidae or to the Cribrilinidae.

Avicularia of this type occur in the common Flustra foliacea, in various species of Membranipora, and in particular in the Onychocellidae, a remarkable family common in the Cretaceous period and still existing.

Mesozoic rocks are represented by slates containing Ammoniles and Monotis, evidently of Triassic age, rocks containing Ammonites Bucklandi of Liassic age, a series of beds rich in plants of Jurassic age, and beds of Cretaceous age containing Trigonia and many other fossils.

The Jurassic and Cretaceous beds are also in part marine and in part terrestrial.

It is formed almost entirely of a succession of sandstones and shales of Cretaceous and Tertiary age - the so-called Carpathian Sandstone - and these are thrown into a series of isoclinal folds dipping constantly to the south.

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 Texas Cretaceous is notably rich in the fossil remains of an invertebrate fauna and in the vicinity of Waco Cretaceous fossils of vertebrates have been obtained.

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.

Cretaceous marls and limestones appear at intervals, extending in places to the edge of the upper plateau, and are extensively developed on the Makonde plateau.

Some Cretaceous or Upper Jurassic rocks occur in the basin of the Fly river.

It appears to consist in the main of a continuation of an axis of old schists and slates, with granite intrusions, and flanked by coastal plains with Cretaceous or Jurassic, and Miocene beds, with Pleistocene sands and reefs and volcanic 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.

Nearly complete skeletons of allied reptiles have been discovered in the Jurassic and Cretaceous rocks of North America.

The deposits belong to the Lower Eocene, where it rests unconformably upon the Cretaceous.

Large deposits of phosphate occur in Russia, and those in the neighbourhood of Kertch have attracted some attention; it is said that the Cretaceous rocks between the rivers Dniester and Volga contain very large supplies of phosphate, though probably of low grade.

Bands of black nodules, highly phosphatic, are found at the top of the Bala limestone in North Wales; beds of concretions occur in the Jurassic series; and important deposits are known in the Cretaceous strata, especially in the Lower Greensand and at the base of the Gault.

The Cretaceous system includes the Waipara series, a belt of chalky limestones with some phosphate beds at Clarendon in eastern Otago.

These Cretaceous limestones are interbedded with glauconitic greensands, as at Moeraki Point in eastern Otago.

The second type of Cretaceous is a terrestrial formation, and is important as it contains the rich coal seams of Greymouth, Westport and Seddonville, which yield a high quality of steam coal.

Cretaceous coals have long been worked in the North Island, north of Auckland, on the shores of the Bay of Islands, where the age of the coal is shown by its occurrence under the Whangarei or Waimio limestone.

The building up of these domes of lavas of intermediate chemical type was followed by the eruption of sheets of andesites and rhyolites in the Thames English Miles so Ioo 200 Cretaceous 'a '

In the Great Plains region the geological structure is very simple, consisting of nearly horizontal strata of Cretaceous rock in the middle and western portions, and of Tertiary rock on the eastern border, but in the mountain region the rocks have been folded and faulted until the structure is intricate and obscure.

In the region east of the Crazy Mountains, in Sweetgrass county, are marine beds of upper Cretaceous.

Produced by long-continued subaerial decay and erosion, in later Cretaceous times this lowland extended from the Atlantic Ocean well toward the interior of North America; since then the whole continent has been generally elevated, and by successive steps the Appalachian belt has been raised to form a wide but relatively low arch.

The master streams of the present have inherited their channels from the drainage systems of the Cretaceous lowland, and though raised athwart the courses of the lowland trunk streams the great arch was developed so slowly that these channels could be maintained through pari passu deepening.

There is an older series, ranging from the Devonian to the Cretaceous, which is folded and faulted and forms all the higher hills, and there is a newer series of Tertiary age, which lies nearly horizontal and rests unconformably upon the older beds.

The higher part of the Cretaceous is absent, and it appears to have been during this period that the principal folding of the older beds took place.

The Inferior Cretaceous rocks include the Neocomian and Gault (Albian and Aptian) subdivisions, and form the flanks of the mountains in the Tell.

Rocks of Upper Cretaceous age are represented in all their stages.

Especially noteworthy was the discovery of birds with teeth both in Europe (Archaeopteryx) and in North America (Hesperornis), of Eocene stages in the history of the horse, and of the giant dinosauria of the Jurassic and Cretaceous in North America.

These latter discoveries supply us with the ancestry of the elephants and many other forms. They round out our knowledge of Tertiary history, but leave the problems of the Cretaceous mammals and of their relations to Tertiary mammals still unsolved.

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.

Ortmann has traced the centre of dispersal of the fresh-water Crawfish genera Cambarus, Potamobius and Cambaroides to eastern Asia, where their common ancestors lived in Cretaceous time.

Among the ammonites of the Jurassic and Cretaceous periods types occur which in their external appearance so closely resemble each other that they could be taken for members of a single series, and not infrequently have been taken for species of the same genus and even for the same species; but their early stages of development and, in fact, their entire individual history prove them to be distinct and not infrequently to belong to widely separated genetic series.

We observe the contemporaneous and largely independent radiations of the hoofed animals in South America, in Africa and in the great ancient continent comprising Europe, Asia and North America; we observe the Cretaceous radiation of hoofed animals in the northern hemisphere, followed by a second radiation of hoofed animals in the same region, in some cases one surviving spur of an old radiation becoming the centre of a new one.

Successive discoveries have revealed certain grand centres, such as (1) the marsupial radiation of Australia, (2) the littleknown Cretaceous radiation of placental mammals in the northern hemisphere, which was probably connected in part with the peopling of South America, (3) the Tertiary placental radiation in the northern hemisphere, partly connected with Africa, (4) the main Tertiary radiation in South America.

In his history of the Arietidae Hyatt points out that toward the close of the Cretaceous this entire group of ammonites appears to have been affected with some malady; the unrolled forms multiply, the septa are simplified, the ornamentation becomes heavy, thick, and finally disappears in the adult; the entire group ends by dying out and leaving no descendants.

The Cretaceous rocks take a far larger share in the formation of the country.

The eruptions are said to have begun with the ejection of syenites, diorites and diabases, which probably took place at the close of the Cretaceous or the beginning of the Eocene period.

The Westphalian plain is broken by extensive outcrops of the underlying cretaceous beds, and is not very fertile, except in the Hellweg, a zone between the Haarstrang and the Lippe.

The strata here are Cretaceous or early Tertiary, lying nearly horizontal.

The Sierra Nevada may be described, in a very general way, as a great mountain block, largely composed of granite and deformed metamorphosed rocks, reduced to moderate relief in an earlier (Cretaceous and Tertiary?) cycle of erosion, sub-recently elevated with a slant to the west, and in this position sub-maturely dissected.

Comanchean System.This system was formerly classed as the lower part of the Cretaceous, but there are strong reasons for regarding it as a separate system.

Its distribution is very different from that of the Upper Cretaceous, and there is a great and widespread unconformity between them.

On the western coast the term Shastan is sometimes applied to Lower Cretaceous.

Widespread changes at the end of the period exposed the areas where deposition has been in progress during the period to erosion, and the (Upper) Cretaceous formations rest upon the Comanchean unconformably in most parts of the country.

Cretaceous System.This system is much more extensively developed in the United States than any other Mesozoic system.

Unlike the Cornanchean, the larger part of the Cretaceous system is of marine origin.

The most distinctive feature of the Cretaceous of the Atlantic coastal plain is its large content of greensand marl (glauconite).

On the Pacific coast the Cretaceous formations are sometimes grouped together under the name of Chico.

The Cretaceous system is thick.

The Eocene beds are unconformable, generally, upon the Cretaceous, and unconformable beneath the Miocene.

On the Pacific coast the marine Eocene lies west of the Sierras, and between it and the Cretaceous there is a general, and often a great, unconformity.

Under these conditions sediments from the high lands were washed out and distributed widely over the plains, giving rise to a thin but widespread formation of ill-assorted sediment, without marine fossils, and, for the most part, without fossils of any kind, and resting unconformably on Cretaceous, Eocene and Miocene formations.

Cloverly formation (upper part may be Cretaceous) 30- 300 ft.

Most of the plains are underlain by Cretaceous and early Tertiary shales and sandstones lying nearly unaltered and undisturbed where they were deposited, although now raised far above sea-level, particularly along the border of the Rocky Mountains where they were thrust up into foot-hills when the range itself was raised.

Coal and lignitic coal are the principal economic minerals met with in this central plain, though natural gas occurs and is put to use near Medicine Hat, and " tar sands " along the northeastern edge of the Cretaceous indicate the presence of petroleum.

More important than the hills are the narrow and often rather deep river valleys cut below the general level, exposing the soft rocks of the Cretaceous and in many places seams of lignite.

The several ranges of the Cordillera show very different types of structure and were formed at different ages, the Selkirks with their core of pre-Cambrian granite, gneiss and schists coming first, then the Coast Ranges, which seem to have been elevated in Cretaceous times, formed mainly by a great upwelling of granite and diorite as batholiths along the margin of the continent and sedimentary rocks lying as remnants on their flanks; and finally the Rocky Mountains in the Laramie or early Eocene, after the close of the Cretaceous.

This latest and also highest range was formed by tremendous thrusts from the Pacific side, crumpling and folding the ancient sedimentary rocks, which run from the Cambrian to the Cretaceous, and faulting them along overturned folds.

In the Rocky Mountains proper no eruptive rocks have broken through, so that no ore deposits of importance are known from them, but in the Cretaceous synclines which they enclose valuable coal basins exist.

Modiolopsidae.-Extinct; Silurian to Cretaceous; adductor muscles sub-equal.

Caprinidae.-Shell inequivalve; fixed valve spiral or conical; free valve coiled or spiral; Cretaceous.

Monopleuridae.-Shell very inequivalve; fixed valve conical or spiral; free valve operculiform; Cretaceous.

The islands of these outer arcs consist chiefly of crystalline schists and limestones, overlaid by Jurassic, Cretaceous and Tertiary deposits.

Eruptive rocks of supposed Cretaceous age are met with in these outer islands, but Tertiary and recent volcanic lavas are confined to the innermost arc. Halmahera lies outside these arcs.

It appears to consist chiefly of gabbro, peridotite, serpentine and other very basic eruptive rocks, which are believed to be of Cretaceous age.

The chief geological formations belong to the Cretaceous system, backed towards the north and east by Jurassic and Triassic formations.

In the production of these mountains and plateau there was first, at the close of the Cretaceous period, an upheaval of the earth's substance to form a mountain rim and a depressed basin.

In the west it seems to be entirely Eocene, but towards the east intercalated beds with Inoceramus, &c., indicate that it is partly of Cretaceous age.

The Mesozoic belt of the Bavarian and Austrian Alps consists mainly of the Trias, Jurassic and Cretaceous beds playing a comparatively subordinate part.

The Jurassic and Cretaceous beds also differ, though in a less degree, from those of northern Europe.

Tithonian fossils, characteristic of southern Europe, occur in the upper Jurassic, while the Gosau beds, belonging to the upper Cretaceous, contain many of the forms of the Hippuritic sea.

Jurassic and Cretaceous beds play a larger part than on the northern border, but the Trias still predominates.

Jurassic and Cretaceous beds form the greater part of the Mesozoic band.

It consists almost entirely of Jurassic and Cretaceous beds, the Trias in these outer ranges being of very limited extent.

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.

Cretaceous beds also have been recorded by Backing.

Upon its northern margin lie the nearly undisturbed Cretaceous and Tertiary beds which cover the greater part of Belgium.

Except along the southern border of the Ardennes, and at one or two points in the middle of the Palaeozoic massif, Triassic and Jurassic beds are unknown in Belgium, and the Palaeozoic rocks are directly and unconformably overlaid by Cretaceous and Tertiary deposits.

The Cretaceous beds are not extensive, but the Wealden deposits of Bernissart, with their numerous remains of Iguanodon, and the chalk of the district about the Dutch frontier near Maastricht, with its very late Cretaceous fauna, are of special interest.

Africa during the Cretaceous period (after the deposition of the Stormberg beds), and drilled these enormous craters through all the later formations.

Geology.Germany consists of a floor of folded Palaeozoic rocks upon which rest unconformably the comparatively little disturbed beds of the Mesozoic system, while in the North German plain a covering of modern deposits conceals the whole of the older strata from view, excepting some scattered and isolated outcrops of Cretaceous and Tertiary beds.

Towards the north, in Hanover and Westphalia, the Triassic beds are followed by Jurassic and Cretaceous deposits, the latter being here the more important.

As in the south of England, the lower beds of the Cretaceous are of estuarine origin and the Upper Cretaceous overlaps the Lower, lying in the valley of the Ruhr directly upon the Palaeozoic rocks.

In Saxony also the upper Cretaceous beds rest directly upon the Palaeozoic or Archaean rocks.

Still more to the east, in the province of Silesia, both Jurassic and Cretaceous beds are again met with, but they are to a large extent concealed by the recent accumulations of the great plain.

In both areas they are accompanied by Jurassic, and occasionally by Cretaceous, beds; but of the latter there are only a few small patches.

Cretaceous rocks occur around the basalt platform of the Cameroon mountain and generally along the coastal belt.

The upper part certainly belongs to the Cretaceous formation; the lower part has been considered to be of Karroo age by some geologists, while others regard the whole formation to be of Cretaceous age.

In many instances the Tertiary formation, which occurs betweeii Esna and Cairo, unconformably overlies the Cretaceous, the Lower Eocene being absent.

The deposits of the boulder formation rest generally on limestone of the Cretaceous period, which in many places comes near the surface and forms cliffs on the sea-coast.

Much of the Danish chalk, including the wellknown limestone of Faxe, belongs to the highest or " Danian " subdivision of the Cretaceous period.

There the boulder clay lies immediately on the primitive rock, except in the south-western corner of the island, where a series of strata appear belonging to the Cambrian, Silurian, Jurassic and Cretaceous formations, the true Coal formation, &c., being absent.

Some parts of Denmark are supposed to have been finally raised out of the sea towards the close of the Cretaceous period; but as a whole the country did not appear above the water till about the close of the Glacial period.

The salt of Bex in Switzerland is Jurassic, whilst Cretaceous salt occurs in Westphalia and Algiers.

Deposits of salt, regarded as either Cretaceous or Tertiary, occur in the island of Petite Anse, west of Vermilion Bay, in Louisiana.

Finally, beyond the Balkans lies the great Rumanian depression, occupied chiefly by undisturbed Cretaceous and Tertiary strata.

Upon the margins, however, Cretaceous beds are found.

The eastern parts of Greece are composed almost entirely of Cretaceous beds, but nevertheless they must be considered to belong to the central area, for the folds which affect them are nearly at right angles to those of the western chains.

In the south, the older beds disappear and the whole chain is formed chiefly of Cretaceous beds, though Eocene and probably Jurassic rocks are Medit Er R Anean Plutonic Rocks Volcanic Rocks o Active Volcanoes present.

Crystalline rocks crop out at several capes; Cretaceous limestones, containing an abundant and specific fauna of gigantic ammonites, occur at Dui on the west coast, and Tertiary conglomerates, sandstones, marls and clays, folded by subsequent upheavals, in many parts of the island.

Archean gneiss, Cambrian sandstone, Silurian quartzite, limestone and schist, Jurassic sandstone and limestone, Cretaceous sandstone, and Tertiary basalts, gabbros, and granitic rocks all enter into the composition of the islands.

The next Secondary rocks (Cretaceous) succeed them unconformably.

Rocks belonging to the Cretaceous system at one time covered considerable areas on both sides of the Highlands, but they have been entirely stripped off the eastern side, while on the western they have been reduced to a few fragmentary patches, which have survived because of the overlying sheets of basalt that have protected them.

They are a prolongation of the Cretaceous deposits of Antrim (Ireland).

The Eastern Cordillera is composed of gneiss, mica and chlorite schist and other crystalline rocks of ancient date; the Western Cordillera, on the other hand, is formed of porphyritic eruptive rocks of Mesozoic age, together with sedimentary deposits containing Cretaceous fossils.

Most of the country between the Andes and the sea is covered by Tertiary and Quaternary beds; but the range of hills which runs north-west from Guayaquil is formed of Cretaceous and porphyritic rocks similar to those of the Andes.

The island is composed largely of crystalline and metamorphic rocks, but contains some cretaceous areas which hold extensive beds of coal, especially on the east coast.

Geologically the group is composed mainly of Triassic, Cretaceous and Tertiary strata, penetrated by intrusive rocks.

The Ionian islands consist almost entirely of Cretaceous and Tertiary beds, but in Corfu Jurassic deposits belonging to various horizons have also been found.

These are overlaid conformably by a thick series of platy limestones, known as the Viglas limestone, which appears to represent the rest of the Jurassic system and also the lower part of the Cretaceous.

Then follows a mass of dolomite and unbedded limestones containing Hippurites and evidently of Upper Cretaceous age.

The Eocene beds are folded with the Cretaceous, and in many places the two formations have not yet been separately distinguished.

The surface is for the most part undulating, but on the whole little above sea-level; the highest elevations are in the south-east, where Cretaceous hills (the oldest geological formation on the island) reach heights of upwards of 350 ft.

South of the Yarmuk the formation is Cretaceous, Hauran basalt being found only in the eastern portion.

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 Upper Cretaceous is represented by limestones with bands of chert, and contains Ammonites, Baculites, Hippurites and other fossils.

Through these, again, pierce other granites in dikes or lava flows, and overlying the whole are limestones of Cretaceous and Tertiary age, themselves cut through by later volcanic eruptions.

The end of the Cretaceous period saw the beginning of a series of great earth movements ushered in by volcanic eruptions on a scale such as the earth has never since witnessed, which resulted in the upheaval of the Himalayas by a process of crushing and folding of the sedimentary rocks till marine fossils were forced to an altitude of 20,000 ft.

The Jurassic beds are followed, generally with perfect conformity, by the Cretaceous, which covers a large part of Afghan Turkestan and probably forms the greater part of the ranges which run south and south-west from the principal watershed.

The lowest beds consist of red grits which contain Neocomian fossils, while the middle and upper Cretaceous consist chiefly of limestone and chalk.

The entire system may be represented in the west, but in the Herat province and in Afghan Turkestan the middle Cretaceous seems to be absent, and it is probable that, as in other regions, the upper Cretaceous covers a much wider area than the lower beds.

But the most important igneous masses are the great intrusions of syenitic granite and of basic rock which penetrate the Cretaceous beds.

These are probably of Eocene or of late Cretaceous age.

Cretaceous beds of marine origin are also found in Cutch, Kathiawar and the Nerbudda valley on the northern margin of the Peninsula, and near Pondicherry and Trichinopoly on its southeastern margin.

There is a striking difference between the Cretaceous faunas of the two areas, the fossils from the north being closely allied to those of Europe, while those of the south (Pondicherry and Trichinopoly) are very different and are much more nearly related to those from the Cretaceous of Natal.

It is now very generally believed that in Jurassic and Cretaceous times a great land-mass stretched from South Africa through Madagascar to India, and that the Cretaceous deposits of Cutch, &c., were laid down upon its northern shore, and those of Pondicherry and Trichinopoly upon its southern shore.

The land probably extended as far as Assam, for the Cretaceous fossils of Assam are similar to those of the south.

The great volcanic outbursts which produced this trap commenced in the Cretaceous period and lasted on into the Eocene period.

These are of Tertiary and Cretaceous ages, the latter rocks resting on a reddish sandstone of older date.

The Cretaceous rocks of the Dombe Grande region (near Benguella) are of Albian age and belong to the Acanthoceras mamillari zone.

Their southern edge is covered with cretaceous deposits, and their eastern edge is covered as well with the tertiary deposits of the Gulf plains.

The former extension of Rhaetic, Liassic and Cretaceous formations in the island is indicated by the presence of fragments of these strata in a large volcanic vent on the plateau, on the south side of the road leading from Brodick to Shiskine.

The fossils from the Rhaetic beds belong to the Avicula contorta zone, those from the Lias to the Ammonites angulatus zone, while the blocks of limestone with chert contain Inoceramus, Cretaceous foraminifera and other organisms. The materials yielding these fossils are embedded in a course volcanic agglomerate which gives rise to crags and is pierced by acid and basic igneous ricks.

The low-lying country between the mountain ranges is covered for the most part by Tertiary and Quaternary deposits, but Cretaceous beds occur at several localities.

The Cretaceous beds, which have long been known in west Borneo, are comparatively little disturbed.

Cretaceous beds of somewhat later date are - found in the Marpapura district in south-east Borneo.

Volcanic rocks of Tertiary and late Cretaceous age are extensively developed, especially in the Muller Mountains.

Limestones of Eocene or Cretaceous age form a large part of the Taurus, but the interior zone probably includes rocks of earlier periods.

Cretaceous limestones and serpentine take a large part in the formation of these mountains, while even the Oligocene is involved in the folds.

West of Sinope Cretaceous beds form a long strip parallel to the shore line.

Triassic, Jurassic and Cretaceous beds form a band south of the Sea of Marmora, probably the continuation of the Mesozoic band of the Black Sea coast.

The coal-bearing rocks are confined to the Upper Cretaceous, and almost wholly to the Laramie formation.

These are supposed to be of Cretaceous age, but no fossils have been found in them.

The older rocks are overlaid unconformably by Cretaceous beds, consisting chiefly of sandstones with seams of coal, the whole series thinning rapidly towards the north and thus indicating the neighbourhood of the old shore-line.

The fossils are very similar to those of the South Indian Cretaceous, but very different from those of the corresponding beds in the Nerbudda valley.

The Cretaceous formation occurs in the provinces of Malmohus and Kristianstad and a few small patches are found in the province of Blekinge.

Along the coast lies a belt of granite and schist overlaid unconformably by Cretaceous and Tertiary deposits; inland the mountains are formed chiefly of folded Mesozoic beds, together with volcanic rocks of later date.

They are strongly folded and are overlaid unconformably by Cretaceous and Tertiary deposits.

In the north both the Cretaceous and Tertiary beds of this zone are limited in extent, but towards the south Mesozoic beds, which are at least in part Cretaceous, form a band of considerable width.

The Chilean Andes correspond with the Western Cordillera of Bolivia and Peru, and consist almost entirely of Jurassic and Cretaceous beds, together with the products of the Tertiary eruptions.

The Cretaceous beds form a synclinal upon the eastern side of the chain (and, in general, beyond the Chilean boundary), while the Jurassic beds are thrown into a number of folds which form the axis and the western flank.

The Trias is known only at La Ternera near Copiapo, where coal-seams with Rhaetic plants have been found; but the rest of the Mesozoic series, from the Lias to the Upper Cretaceous, appears to be represented without a break .of more than local importance.

They are not confined to any one horizon, but occur irregularly throughout the Jurassic and occasionally also amongst the Cretaceous strata.

Westwards, looking towards Afghanistan, line upon line of broken jagged ridges and ranges, folds in the Cretaceous series overlaid by coarse sandstones and shales, follow each other in order, preserving their approximate parallelism until they touch the borders of Baluchistan.

The mountain ranges of Baluchistan consist chiefly of Cretaceous and Tertiary beds, which are thrown into a series of folds running approximately parallel to the mountain ridges.

Besides the Cretaceous and Tertiary beds, Jurassic rocks are known to take a considerable part in the formation of the hills of British Baluchistan.

But in the upper Cretaceous and lower Tertiary, especially in north-western Baluchistan, there is an extensive development of volcanic tuffs and conglomerates, which are probably contemporaneous with the Deccan Traps of India.

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.

Its northern shores were washed by the Sea of Tethys, which, at least in Jurassic and Cretaceous times, stretched across the Old World from west to east, and in this sea were laid down the marine deposits of the Himalaya.

The Spiti shales are succeeded conformably by Cretaceous beds (Gieumal sandstone below and Chikkim limestone above), and these are followed without a break by Nummulitic beds of Eocene age, much disturbed and altered by intrusions of gabbro and syenite.

The Cretaceous system is very limited in extent.

Here both Cretaceous and Tertiary forms are found, and the Mondego beds seem to represent the passage between the.

The eastern ranges of the Bolivian Andes are formed of Palaeozoic rocks with granitic and other intrusions; the Western Cordillera consists chiefly of Jurassic and Cretaceous beds, together with the lavas and ashes of the great volcanoes; while the intervening plateau is covered by freshwater and terrestrial deposits through which rise ridges of Palaeozoic rock and of a series of red sandstones and gypsiferous marls of somewhat uncertain age (probably, in part at least, Cretaceous).

Marine fossils found by Gustav Steinmann in the middle of the series are said to indicate an age not earlier than the Jurassic, and Steinmann refers them to the Lower Cretaceous.

The Pterosaurians of the Cretaceous period, just before their extinction both in Europe and in North America, were of enormous size, and some became toothless.

The' four topographic belts of the state correspond very closely to the outcrops of its geological formations; the rocks of the Appalachian belt being of Palaeozoic age; the formation of the Highlands, Archaean; that of the Triassic Lowland, Triassic; that of the irregular hills of the Coastal Plain, Cretaceous and Tertiary.

The western plains contain isolated ridges of the old Archean and Lower Palaeozoic rocks; but in the main, they consist of plains of Cretaceous beds covered by Cainozoic drifts.

The Talbragar beds, then, may be representative of the Jurassic; and the underlying Hawkesbury Sandstone may be Upper Triassic. The Cretaceous system is widely developed in the western part of the state, where it is represented by two divisions.

The Rolling Downs formation is regarded as Lower Cretaceous.

The opal beds contain Cretaceous fossils such as Cimoliosaurus.

An occurrence of Upper Cretaceous beds occurs in the coastal district at Nimbin on the Richmond river.

Artesian water is also obtainable in other than Cretaceous rocks.

Some of the Loricata have persisted with little change from the Cretaceous period to the present day.

It is built up of nearly uniform sheets of Mesozoic rock, the various beds of the Jurassic lying above the New Red Sandstone (Triassic), and dipping south-eastward under the successive beds of the Cretaceous system.

In exactly the same way the whole of the south-east of the island appears to have been covered uniformly with gently dipping beds of Tertiary sands and clays, beneath which the Cretaceous strata dipped.

In these hollows the Tertiary rocks were protected from erosion, and remain to form the London and the Hampshire Basins respectively, while on the anticlinal axis the whole of the Tertiary and the upper Cretaceous strata have been dissected away, and a complex and beautiful configuration has been impressed on the district of the Weald.

Steep towards the west, where it overlooks the low Lias plain as the Oolitic escarpment, the land falls very gently in slopes of Oxford Clay towards the Cretaceous escarpments on the south and east.

The dominating surface-feature formed by the Cretaceous rocks is the Chalk escarpment, the northern edge of the great sheet of chalk that once spread continuously over the whole south-east.

From the middle of this plain the core of Lower Cretaceous sandstones known as the Hastings Beds emerges steeply, and reaches in the centre an elevation of 796 ft.

But, on the other hand, the broad clay plains of all formations, the Cretaceous sandstones, and the Triassic plain, are peopled more densely than any other district without mineral wealth or sea trade.

Lying upon the Cretaceous rocks in the S.E.

Elevation gradually caused more, nd to appear in later Jurassic a.nd early Cretaceous times when a.

And whereas the main range is built up of hard eruptive or crystalline rocks, the subsidiary chains are composed of softer (Cretaceous and Tertiary) laminated formations, which easily become disintegrated and dislocated.

These basins or ` longitudinal folds ' are enclosed on the south by the long high ridge of dark slates, which extends parallel to the crystalline [main] chain from the neighbourhood of Sukhum-Kale to the Krestovaya Gora [pass of Darial.] Behind this slate crest spreads a confused multitude of hills, Jurassic and Cretaceous in their formation..

The rest of the Daghestan region consists of a series of roughly parallel folds, of Jurassic or Cretaceous age, ranging in altitudes from 7500 up to 12,500 ft., separated from one another by deep gorge-like river glens which cut it up into a number of arid, treeless plateaus which have something of the appearance of independent ranges, or rather elongated tablelands of a mountainous character.

On the northern flank the folded beds are followed by a zone of Jurassic and Cretaceous beds which rapidly assume a gentle inclination towards the plain.

Upon the Palaeozoic beds rest a series of Mesozoic deposits, beginning with the Lias and ending with the Upper Cretaceous.

Rocks of Cretaceous and Tertiary ages are confined to the maritime zone.

During the Triassic and Jurassic periods the genus Baiera - no doubt a representative of the Ginkgoales--was widely spread throughout Europe and in other regions; Ginkgo itself occurs abundantly in Mesozoic and Tertiary rocks, and was a common plant in the Arctic regions as elsewhere during the Jurassic and Lower Cretaceous periods.

Through the succeeding ages the Ginkgoales were represented by numerous forms, which gradually became more restricted in their distribution and fewer in number during the Cretaceous and Tertiary periods, terminating at the present day in one solitary survivor.

The axis of the Transylvanian Alps consists of sericite schists and other similar rocks; and these are followed on the south by Jurassic, Cretaceous and Early Tertiary beds.

The Jurassic and Cretaceous beds are ordinary marine sediments, but from the Cenomanian to the Oligocene the deposits are of the peculiar facies known in the Alps and Carpathians as Flysch.

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.

Cretaceous fossils have been found abundantly in this series, but it is still possible that earlier systems may be represented.

The Western Cordillera is the direct continuation of the Western Cordillera of Ecuador, and, like the latter, to judge from the scattered observations which are all that are available, consists chiefly of sandstones and porphyritic rocks of the Cretaceous series.

The Central Cordillera is the direct continuation of the Eastern Cordillera of Ecuador, and is formed chiefly of gneiss and other crystalline rocks, but sedimentary deposits of Cretaceous age also occur.

Finally the Eastern branch, known as the Cordillera of Bogota, is composed almost entirely of Cretaceous beds thrown into a series of regular anticlinals and synclinals similar to those of the Jura Mountains.

Cretaceous rocks occur only near the coast.

The Thames at Teddington, fed largely from cretaceous areas, fell during ten days in September 1898 (the artificial abstractions for the supply of London being added) to about one-sixth of a cubic foot, and since 1880 the discharge has occasionally fallen, in each of six other cases, to about one-fifth of a cubic foot per second per woo acres.

The Cretaceous rocks on the south side of the island rapidly rise in inclination till they become nearly vertical.

In the west portion of the state, which belongs to the Cretaceous formation, chalks and a species of native quicklime are very prominent in the river bluffs.

The same author also discusses the proposition from another standpoint, namely, the condition of the earth's surface in Cretaceous times.

His theory is that in the early Cretaceous epoch the animals of the world were mostly aerial, amphibious, aquatic or arboreal; the flora of the land being undeveloped as compared with its present state.

On the other hand, towards the close of the Cretaceous epoch (when the Chalk was in course of deposition), the spread of a great upland flora vastly extended the territory available for mammalian life.

In the middle division, or from the mouth of the Voronezh to the point where it makes its nearest approach to the Volga, the stream cuts its way for the most part through Cretaceous rocks, which in many places rise on either side in steep and elevated banks, and at intervals encroach on the river-bed.

Be this as it may, the Apennines, excepting in Calabria, are formed chiefly of Triassic, Jurassic, Cretaceous, Eocene and Miocene beds.

In the northern Apennines the elevation of the sea floor appears to have begun at an earlier period, for the Upper Cretaceous of that part of the chain consists largely of sandstones and conglomerates.

Within that period the principal valleys were excavated, and their lower parts have been filled up subsequently with J urassic, Cretaceous and Tertiary deposits.

One of the most striking instances of this is the very thick Cretaceous and Tertiary deposits which cover the bottom of the valley of the Vakhsh (right tributary of the Amu) and are continued for about 300 m.

Cretaceous and Tertiary deposits occur extensively along the edge of the highlands.

Upper and Middle Cretaceous, containing phosphates, gypsum, naphtha, sulphur and alum, attain thicknesses of 2000 and 5000 ft.

They are of special interest, since they have been shown to be the surviving forms of a group species which have been identified from Jurassic and Cretaceous rocks.

Elsewhere east of the Morava the prevailing rocks belong to the Cretaceous series, which enters Servia from Bulgaria.

Denudation, consequent on the renewed uplift of the country, affected the Jurassic beds until the middle of Cretaceous times.

The sea then returned, in the north-east at any rate, and the first Cretaceous deposits indicate the nearness of a shore-line.

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.

It is just possible, however, that here and there the Cretaceous sea that spread over Devonshire may have penetrated the Irish area.

After Devonian times the region seems to have been dry land until the commencement of the Upper Cretaceous period, when it was overspread by the Cenomanian sea, and the deposits of that sea lie flat upon the older sediments.

Towards the north-west, also, the Palaeozoic foundation falls beneath an increasing thickness of Cretaceous beds and lies buried far below the surface.

West of Cracow the Cretaceous beds are underlaid by Jurassic and Triassic deposits, the general dip being eastward.

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 deposits of this sea are now visible in the large basin of Upper Cretaceous beds which stretches from Dresden southeastward through Bohemia.

Since the close of the Cretaceous period the Bohemian massif has remained above the sea; but the depression which lies immediately outside the Carpathian chain has at times been covered by an arm of the sea and at other times has been occupied by a chain of salt lakes, to which the salt deposits of Wieliczka and numerous brine springs owe their origin.

A narrow band, of Cretaceous age, occurs also on the east coast, for about 120 m., between Vatomandry and Mananjary.

Westward of and above these strata, the Middle and Upper Jurassic formations are found (Lias, Lower Oolite, Oxfordian, &c.), with well-marked and numerous fossils (Ammonites, Nerinaea, Natica, Astarte, Rhynchonella, Echinodermata, &c.); then the Cretaceous rocks, both these and the Jurassic series being largely developed, the Cretaceous fossils including Nautilus, Belemnites, Ostrea, Gryphaea, &c., and some very large Ammonites (Pachydiscus).

The Crystal Mountains of Angola may represent its western boundary; while the absence of mesozoic strata beneath the Cretaceous rocks of the mid-Sahara indicates that the system of Karroo lakeland had here reached its most northerly extension.

The Cretaceous seas appear to have extended into the central Saharan regions, for fossils of this age have been discovered in the interior.

On the west coast Cretaceous rocks extend continuously from Mogador to Cape Blanco.

They are again absent up to the Sunday river in Cape Colony, where Lower Cretaceous rocks (for long considered to be of Oolitic age) of an inshore character are met with.

Strata of Upper Cretaceous age occur in Pondoland and Natal, and are of exceptional interest since the fossils show an intermingling of Pacific types with other forms having European affinities.

In Mozambique and in German East Africa, Cretaceous rocks extend from the coast to a distance inland of over roo m.

In Abyssinia the Ashangi traps are certainly post-Oolitic. In East Africa the fissure eruptions are considered to belong to the Cretaceous.

In northern Africa a continuous sequence of volcanic events has taken place from Eocene times to latest Tertiary; but in South Africa it is doubtful if there have been any intrusions later then Cretaceous.

The Kimeridge clay is succeeded by the Spilsby sandstone, Tealby limestone, Claxby ironstone, and carstone which represent the highest Jurassic and lowest Cretaceous rocks.

In the Cretaceous system of the Wolds, the Lower Greensand runs nearly parallel with the Upper Oolite past South Willingham to the Humber.

It forms most of the higher summits, but west of the Pic d'Anie it disappears beneath an unconformable covering of Cretaceous deposits.

On the French side the central zone is followed by (1) the zone of Ariege, consisting of Lower Cretaceous and Jurassic beds, together with granitic masses; (2) the zone of the Petites Pyrenees, Upper Cretaceous and Eocene; and (3) the zone of the Corbieres, consisting of Eocene and Primary rocks.

On the Spanish side, from north to south, are (1) the zone of Mont Perdu, Upper Cretaceous and Eocene; (2) the zone of Aragon, Eocene; and (3) the zone of the Sierras, Trias, Cretaceous and Eocene.

On the northern side granitic masses occur in the zone of Ariege amongst the Jurassic and Lower Cretaceous beds.

On the southern side they are not found except in the axial zone, and the Jurassic and Lower Cretaceous deposits are reduced to a narrow band.

The lower members of the Cretaceous series include an important fresh-water formation (sandstones and clays), which extends from the Cantabrian coast through the provinces of Santander, Burgos, Soria and Logrono, and is supposed to represent the English Wealden series.

The Nubian sandstone borders the Libyan desert on the south and south-west, but it is doubtful if this sandstone is of Cretaceous or earlier date.

Upon it, in the trough thus formed, rest conformably the basal strata of the Cretaceous; the Jurassic and Triassic being wholly absent (unless in the extreme north-west).

There are almost no Cretaceous outcrops except on the streams, especially the Niobrara, Republican and Platte rivers - and in the Bad Lands.

Twelvetrees, it is probably Cretaceous.

The Jurassic and Cretaceous formations, which in the Southern Cordillera are situated outside of the range to the east, form to a considerable extent the mass of the great range, together with quartz porphyry, the Tertiary, granite and other eruptive rocks, which have been observed along all the chain in South America up to Alaska in the north.

The Cretaceous beds lie in a broad synclinal upon the eastern flank, but the greater part of the chain is formed of Jurassic beds, through which, on the western margin, rise the numerous andesitic volcanic centres.

Of the three main chains into which the mountains are now divided, the western branch is formed mostly of Cretaceous beds; but the inner chains no longer consist exclusively of the older rocks, and Cretaceous beds take a considerable share in their formation.

The Mesozoic era, as defined in geological textbooks, includes the Triassic, Jurassic and Cretaceous epochs; but from the point of view of the evolution of plants and the succession of floras, this division is not the most natural or most convenient.

No undoubted Angiosperms have yet been found below the Cretaceous system.

The calcareous Siphoneae are represented by several forms, identified as species of Diplopora, Triploporella, Neomeris and other genera, from strata ranging from the lower Trias limestones of Tirol to the Cretaceous rocks of Mexico and elsewhere.

The Gleicheniaceae appear to have been represented by Triassic species in North America and Europe, and more abundantly in Jurassic, Weal den, or Lower Cretaceous rocks 3 4 in Belgium, Greenland, Poland s and elsewhere.

A few tree-ferns which may be included in this family - such as Protopteris - have been described from Wealden and Lower Cretaceous rocks of England, Germany and Austria.

Cycadean stems have been found also in the uppermost Jurassic, Wealden and Lower Cretaceous rocks of England, India and other parts of the world.

The fortunate discovery of several hundred Cycadean stems in the United States, of Lower Cretaceous and Upper Jurassic age, has supplied abundant material which has lately been investigated and is still receiving attention at the hands of Mr Wieland.

One large specimen is figured by Heer from Lower Cretaceous rocks of Greenland, and by the side of the frond is shown a carpel with lateral ovules, as in the female flower of Cycas; but an examination of the type-specimen in the Copenhagen Museum led the present writer to regard this supposed carpel as valueless.

Williamsonia occurs in the Upper Gondwana rocks of India; it is recorded also from strata ranging from the Rhaetic to the Lower Cretaceous period in England, Portugal, Sweden, Bornholm, Greenland, Italy and North America.

This form of stem, of a habit entirely different from that of recent Cycads and extinct Bennettites, points to the existence in the Mesozoic era of another type of Gymnosperm allied to the Bennettitales of the Jurassic and Cretaceous periods by its flowers, but possessing a distinctive character in its vegetative organs.

Androstrobus Balduini from Bathonian rocks of France; Zamites familiaris, described many years ago by Corda, from Lower Cretaceous rocks of Bohemia, and Androstrobus Nathorsti, from Wealden beds in Sussex.

C. Jeffrey have recently shown that some Lower Cretaceous specimens of the well-known genus Brachyphyllum obtained from Staten Island, N.Y., possess wood of the Araucarian type.

This genus has long been known as a common and widely spread Jurassic and Cretaceous conifer, but owing to the absence of petrified specimens and of well-preserved cones, it has been impossible to refer it to a definite position in the Coniferales.

A flower of a rather different type, Pseudaraucaria major, exhibiting in the occurrence of two seeds in each scale an approach to the cones of Abietineae, has been described by Professor Fliche from Lower Cretaceous rocks of Argonne.

Hollick and Jeffrey have recently added to our knowledge of the anatomy of Cretaceous FIG.

Cones of Lower Cretaceous age have been described by Fliche from Argonne, which bear a close resemblance to the female flowers of recent species of Cedrus.

At a later stage - in postWealden days - it was the appearance of Angiosperms, probably in northern latitudes, that formed the chief motive power in accelerating the transition in the fades of plant-life from that which marked what we have called the Mesozoic floras, to the vegetation of the Upper Cretaceous and Tertiary periods.

A flora consisting entirely, with a single doubtful exception, of Gymnosperms and Cryptogams gives place to one containing many flowering plants; and these increase so rapidly that before long they seem to have crowded out many of the earlier types, and to have themselves become the dominant forms. Not only do Angiosperms suddenly become dominant in all known plantbearing deposits of Upper Cretaceous age, but strangely enough the earliest found seem to belong to living orders, and commonly have been referred to existing genera.

From Cretaceous times onwards local distribution may change; yet the successive floras can be analysed in the same way as, and compared with, the living floras of different regions.

Dakota a remarkable series has been discovered, lying unmistakably between marine Upper Jurassic rocks below and Upper Cretaceous above.

There has been a certain amount of confusion as to the exact strata in which Amer i can Cretaceous.

Whatever doubt may be left as to the exact botanical position of these early Lower Cretaceous Angiosperms, it is clear that both Monocotyledons and Dicotyledons are represented by several types of leaves, and that the flora extended over wide areas in North America and Greenland, and is found again at a few points in Europe.

Newberry, seem to belong to the commencement of the Upper Cretaceous period.

In the central parts of North America the lacustrine plant-bearing deposits are of enormous thickness, the Dakota series being followed by marine Cretaceous strata known as the Colorado and Montana groups, and these being succeeded conformably by a thousand feet or more of lacustrine shales, sandstones and coal-seams, belonging to the Laramie series.

This also contains occasional marine Upper Cretaceous fossils, as well as reptiles of Cretaceous types.

An extensive literature has grown up relating to these Laramie strata, for owing to the Tertiary aspect of the contained plants, geologists were slow to recognize that they could be truly contemporaneous and interbedded with others yielding Cretaceous animals.

So large a proportion of the trees still belongs to the flora of North America that one is apt to overlook the fact that among the more specialized plants some of the largest American orders, such as the Compositae, are still missing from strata belonging to the Cretaceous period.

The imperfection and want of continuity of the records in Europe have made it necessary in dealing with the Cretaceous floras for us to give the first place to America.

But it is now advisable to return to Europe, where cretaceous.

Upper Cretaceous plants are not uncommon, and the position of the deposits in the Cretaceous series can often be fixed accurately by their close association with marine strata belonging to definite subdivisions.