Calcareous Sentence Examples

In Clausilia, according to the observations of C. Gegenbaur, the primitive shell-sac does not flatten out and disappear, but takes the form of a flattened closed sac. Within this closed sac a plate of calcareous matter is developed, and after a time the upper wall of the sac disappears, and the calcareous plate continues to grow as the nucleus of the permanent shell.

On the bank of the Tiretaine there is a remarkable calcareous spring, the fountain of St Allyre, the copious deposits of which have formed a curious natural bridge over the stream.

The oak grows most luxuriantly on deep strong clays, calcareous marl or stiff loam, but will flourish in nearly any deep well-drained soil, excepting peat or loose sand; in marshy or moist places the tree may grow well for a time, but the timber is rarely sound; on hard rocky ground and exposed hillsides.

While the rugged and mountainous district of Calabria, extending nearly due south for a distance of more than 150 m., thus derives its character and configuration almost wholly from the range of the Apennines, the long spur-like promontory which projects towards the east to Brindisi and Otranto is merely a continuation of the low tract of Apulia, with a dry calcareous soil of Tertiary origin.

Obviously no more than this is possible until physiologists are able to state much more precisely than at present what is the influence of common salt on the plants of salt-marshes, of the action of calcium carbonate on plants of calcareous soils, and of the action of humous compounds on plants of fens and peat moors.

Habitats rich in mineral salts, especially calcium carbonate, poor in acidic humous compounds, and characterized by ash woods, beech woods, and calcareous pasture.

Calcicole and Calcifuge Species.Plants which invariably inhabit calcareous soils are sometimes termed calcicoles; calcifuge species are those which are found rarely or never on such soils.

It is sometimes said that lime acts as a poison on some plants and not on others, and sometimes that it is the physiological dryness of calcareous soils that is the important factor.

The upper, wide opening of the duct is attached by elastic, peritoneal lamellae to the hinder margin of the left lung; the middle portion of the duct is glandular and thick-walled, for the deposition of the albumen; it is connected by a short, constricted " isthmus " (where the shell-membrane is formed) with a dilated " uterus " in which the egg receives its calcareous shell and eventual pigmentation.

The later beds of the island belong to the Jurassic, Cretaceous and Tertiary systems. At the western foot of the Ida massif calcareous beds with corals, brachiopods (Rhvnchonella inconstans, &c.) have been found, the fossils indicating the horizon of the Kimmeridge clay.

It v e mires very little moisture, grows luxuriantly on the thin calcareous soil of Yucatan and is cultivated almost exclusively by the large landowners.

The Jackson formation south-west of the Lisbon beds, is made up chiefly of grey calcareous clay marls, bluish lignitic clays, green-sand and grey siliceous sands.

Calcareous tufa or travertine occurs in the valley of Matlock and elsewhere, and in some places is still being deposited by springs.

Any good free loam is suitable, but a calcareous loam is the best.

Shell spirally coiled; epipodial tentacles present; operculum thick and calcareous.

Cyclostoma, shell turbinated, operculum calcareous, British.

Shell conical; foot secreting a ventral calcareous plate; animal fixed.

Cephalic shield short, truncated posteriorly; eyes deeply embedded; three calcareous stomachal plates; shell external, with reduced spire.

It is supposed to act in some way as a stimulant in copulation, but possibly has to do with the calcareous covering of the egg-capsule.

Shell largely chitinous, not spiral, its calcareous apex projecting through a small hole in the mantle.

But it was now made to appear that the struthious birds in this respect resembled, not only the duck, but a great many other groups - waders, birds-of-prey, pigeons, passerines and perhaps all birds not gallinaceous - so that, according to Cuvier's view, the five points of ossification observed in the Gallinae, instead of exhibiting the normal process, exhibited one quite exceptional, and that in all other birds, so far as he had been enabled to investigate the matter, ossification of the sternum began at two points only, situated near the anterior upper margin of the side of the sternum, and gradually crept towards the keel, into which it presently extended; and, though he allowed the appearance of detached portions of calcareous matter at the base of the still cartilaginous keel in ducks at a certain age, he seemed to consider this an individual peculiarity.

The surface of the country is remarkably level, with numerous deep ravines in the calcareous conglomerate.

The soil consists, for the most part, either of clay intermixed with sand or of calcareous earth, and is on the whole fruitful.

Calcareous lands are predominant, especially in the uplands.

The material is largely calcareous, and has probably been derived from the disintegration of the reefs, and from the shells of animals living in the shallows.

On the south coast of the same island are coarse-grained, brownish micaceous and light-coloured calcareous sandstone and marls, containing fossils, which render it probable that they are of the same age as the coal-bearing Jurassic rocks of Brora (Scotland) and the Middle Dogger of Yorkshire.

Lime is, in fact, absorbed to an enormous extent by fishes, molluscs, crustacea, calcareous algae and sponges, starfishes, sea-urchins and feather stars, many polyzoa and a multitude of protozoa (mainly the foraminifera).

All these animals have calcareous skeletons or shells of some form and they secrete the calcium from its solution as sulphate, converting it into carbonate.

In so far as it depends on solution of calcareous rock the Semper-Murray theory of coral reefs is unsatisfactory.

Muscovite and biotite are commonly found in siliceous rocks, whilst phlogopite is characteristic of calcareous rocks.

Dorsal valve, showing calcareous spiral coils.

The outer surfaces of the mantle secrete' the shell, which is of the nature of a cuticle impregnated by calcareous salts.

These canals are closed externally and are absent in Rhynchonella, where the amount of calcareous deposit is small.

Calcification and calcareous deposits are extremely common in many pathological conditions.

The tree succeeds in deep, sandy or calcareous loams, and in stiff loams resting on a gravelly bottom.

It has been sought to work again the ancient quarries of Shemtu, but it was found that the marble had been spoilt by ferruginous and calcareous veins.

Orifice concealed at the bottom of a vestibular shaft, surrounded by a solid or vesicular calcareous deposit.

The Ctenostomata are ill adapted for preservation as fossils, though remains referred to this group have been 1 Calcareous spicules have been described by Lomas in Alcyonidium gelatinosum.

In many calcareous forms, .both Cheilostomes and Cyclostomes, the zoarium is rendered flexible by the interposition of chitinous joints at intervals.

In a few Gymnolaemata the ectocyst is merely chitinous, although in most cases the four vertical walls and the basal wall of the zooecium are calcareous.

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.

In Bugula, for instance, a calcareous avicularium of this type is attached by a narrow neck to each zooecium.

Some of the mountains are almost entirely composed of naked calcareous rock, but most of them wereformerly covered to their summits with forests of oaks, chestnuts, or pine trees, now destroyed to provide fuel.

Waves and tidal currents produce their full effects in that region, and in high latitudes the effect of transport of materials by ice is very important; while in the warm water of the tropics the reefbuilding animals and plants (corals and calcareous algae) carry on their work most effectively there.

A particularly fine-grained mud is formed on the low coasts of the eastern border of the North Sea by a mixture of the finest sediment carried down by the slow-running rivers with the calcareous or siliceous remains of plankton.

Pure calcareous sand and calcareous mud are formed by wave action on the shores of coral islands where the only material available is coral and the accompanying calcareous algae, crustacea, molluscs and other organisms secreting carbonate of lime.

Sand may be taken as the predominating deposit on the continental shelves, often with a large admixture of remains of calcareous organisms, for instance the deposits of marl made up of nullipores off the coasts of Brittany and near Belle Isle.

The proportion of calcium carbonate varies greatly according to the amount of foraminifera and other calcareous organisms which it contains.

When the proportion of calcium carbonate in the blue mud is considerable there results a calcareous ooze, which when found on the continental slope and in enclosed seas is largely composed of remains of deep-sea corals and bottom-living foraminif era, pelagic organisms including pteropods being less frequently represented.

The floors of the Caribbean, Cayman and Mexican Basins in the Central American Sea are covered with a white calcareous ooze, which is clearly distinguished from the eupelagic pteropod and globigerina oozes by the presence of abundant large mineral particles and the remains of land plants.

Terrigenous Deposits (formed in deep or shallow water close to land) by a calcareous cement.

Similar formations are found in the Mediterranean, where a dark mud predominates in the western part, passing into a grey, marly slime in the Tyrrhenian Basin and replaced by a typical calcareous ooze in the Eastern Basin.

In the Red Sea the " Pola " expedition discovered a calcareous .00ze similar to that of the Mediterranean, and the formation of a stony crust by precipitation of calcium and magnesium carbonates may be recognized as giving origin to a recent dolomite.

To this inconceivably slowly-growing deposit of inorganic material over the ocean floor there is added an overwhelmingly more rapid contribution of the remains of calcareous and siliceous planktonic and benthonic organisms, which tend to bury the slower accumulating material under a blanket of globigerina, pteropod, diatom or radiolarian ooze.

Thus red clay and radiolarian ooze are distinguished as abyssal deposits in contradistinction to the epilophic calcareous oozes.

Murray and Renard define globigerina ooze as containing at least 30% of calcium carbonate, in which the remains of pelagic (not benthonic) foraminifera predominate and in which remains of pelagic mollusca such as pteropods and heteropods, ostracodes and also coccoliths (minute calcareous algae) may also occur.

These peculiarities, combined with the striking absence of mineral constituents, distinguish the eupelagic globigerina ooze from the hemipelagic calcareous mud.

A very interesting feature is the small proportion of calcium carbonate, the amount present being usually less as the depth is greater; red clay from depths exceeding 3000 fathoms does not contain so much as 1% of calcareous matter.

The centre is occupied by a wide calcareous table-land, to the north of which stretches the plain of Sologne.

They are ridges of aeolian limestone plastered over by a thin layer of corals and other calcareous organisms. The very remarkable "serpuline atolls" are covered by a solid crust made of the convoluted tubes of serpulae and Vermetus, together with barnacles, mussels, nullipores, corallines and some true incrusting corals.

On rich soils the crop is liable to grow too rapidly and yield a"coarse, uneven sample, consequently the best barley is grown on light, open and preferably calcareous soils, while if the condition of the soil is too high it is often reduced by growing wheat before the barley.

They consist of fine clays with nodular calcareous concretions rich in fossils.

Ironstone is found in the Wadhurst Clay, a subdivision of the Hastings beds, clays and calcareous ironstone in the Ashdown sand, but the industry has long been discontinued.

Tuff and travertine are calcareous deposits found in volcanic districts.

There are no affluents of any considerable size, and the only outlets are underground passages or katavothra extending for many miles through the calcareous rocks.

The eggs are elliptical in shape, both poles being equal, and are covered with a shell which may be thin and leathery or hard and calcareous.

It is produced on light shallow soils overlying calcareous rock.

The pulque industry is located on the plateau surrounding the city of Mexico, the most productive district being the high, sandy, arid plain of Apam, in the state of Hidalgo, where the " maguey " (A gave americana) finds favourable conditions for its growth - a dry calcareous surface with moisture sufficiently near to be reached by its roots.

A deposit of sinter and a calcareous sandstone, known as the Kalahari Kalk, considered by Dr Passarge to be of Miocene age, overlies a sandstone and curious breccia (Botletle Schnichten).

These are steeped in water from the mineral springs until they become encrusted with a calcareous deposit which gives them the appearance of fossils.

In the eastern Gulf states there is more calcareous material, represented by limestone or chalk, In the Texan region and farther north the limestone becomes still more important.

The mantle-skirt is always long, and hides the rest of the animal from view, its dependent margins meeting in the middle line below the ventral surface when the animal is retracted; it is, as it were, slit in the median line before and behind so as to form two flaps, a right and a left; on these the right and the left calcareous valves of the shell are borne respectively, connected by an uncalcified part of the shell called the ligament.

In the Cumberland Plateau and Great Valley Regions are a red or brown loam, rich in decomposed limestone and calcareous shales, and sandy or gravelly loaTns.

Some of the smaller islands are of recent calcareous formation.

As there are only one or two small stretches of arable land in Ithaca, the inhabitants are dependent on commerce for their grain supply; and olive oil, wine and currants are the principal products obtained by the cultivation of the thin stratum of soil that covers the calcareous rocks.

With the exception of the coral and a small amount of calcareous sandstone, the rocks are entirely volcanic and range from basalt to trachyte, but are mainly basalt.

Air, flint, glass, rock-crystal, calcareous spar were examined, but without effect.

Calcareous soils, which may also be heavy, intermediate or light, are those which contain more than 20% of lime, their fertility depending on the proportions of clay and sand which enter into their composition; they are generally cold and wet.

For stone fruits a calcareous loam is best; indeed, for these subjects a rich calcareous loam used in a pure and simple state cannot be surpassed.

The dorsal integument or mantle bears, not a simple shell, but eight calcareous plates in longitudinal series articulating with each other.

Later the ciliated ring or velum disappears and seven imbricated calcareous plates, made up of flattened spicules, are formed on the dorsal surface.

The whole surface is uniformly covered with short compressed calcareous spicula embedded in the cuticle.

And although embryology seems to prove that the Neomeniomorphs are derived from forms with a series of shell-valves, nevertheless it seems probable that the calcareous spicules which alone are present in adult Aplacophora preceded the solid shell in evolution.

These " dry diggings " were therefore at first supposed to be alluvial in origin like the river gravels; but it was soon discovered that, below the red surface soil and the underlying calcareous deposit, diamonds were also found in a layer of yellowish clay about 50 ft.

The coastline of the Gulf of Mortvyi Kultuk on the north-east is, on the other hand, formed by a range of low calcareous hills, constituting the rampart of the Ust-Urt plateau, which intervenes between the Caspian and the Sea of Aral.

Bonifacio, which overlooks the straits of that name separating Corsica from Sardinia, occupies a remarkable situation on the summit of a peninsula of white calcareous rock, extending parallel to the coast and enclosing a narrow and secure harbour.

The basement storey is generally built of the soft calcareous stone of the neighbouring hills, and the upper storey, which contains the harem, of painted brick.

The calcareous deposits in Characeae, Corallinaceae and Siphonaceae are at once a protection against attack and a means of support.

The geologic record is, as perhaps is to be expected, exceedingly poor, except as regards the calcareous Siphonales, which are well represented at various horizons, from the Silurian to the Tertiary; even the Diatomaceae, which are found in great quantities in the Tertiary deposits, do not occur at all earlier than the chalk.

They are made by heating to a high temperature an intimate mixture of a calcareous substance and an argillaceous substance.

In this case the action of the water is checked by the film of carbonate of lime which eventually forms on the surface of calcareous cement.

But where the concrete or mortar is not well made and is porous, the continual passage of water through it will gradually break up and dissolve away the calcareous constituents of the cement until its strength is utterly destroyed.

This destructive action is increased if the water contains sulphates or magnesium salts, both of which act chemically on the calcareous constituents of the cement.

It is overlaid towards the west by similar limestones, which contain nummulites and belong to the Eocene period; and these are followed near the coast by the calcareous sandstone of Philistia, which is referred by Hull to the Upper Eocene.

The theatre, covered by a stream of lava, and built partly of small rectangular blocks of the same material, though in the main of concrete, has been superimposed upon the Greek building, some foundations of which, in calcareous stone, of which the seats are also made, still exist.

In Kent they flourish best in a calcareous soil.

Certain markings on slates and sandstones, such as the "fucoids" of Scandinavia and Scotland, the Phycoides of the Fichtelgebirge, Eophyton and other seaweed-like impressions, may indeed be the casts of fucoid plants; but it is by no means sure that many of them are not mere inorganic imitative markings or the tracks or casts of worms. Oldhamia, a delicate branching body, abundant in the Cambrian of the south-east of Ireland, is probably a calcareous alga, but its precise nature has not been satisfactorily determined.

The shores of the Bosporus are composed in the northern portion of different volcanic rocks, such as dolerite, granite and trachyte; but along the remaining course of the channel the prevailing formations are Devonian, consisting of sandstones, marls, quartzose conglomerates, and calcareous deposits of various kinds.

In the following year he published a paper on the analysis of one of the London pump-waters (from Rathbone Place, Oxford Street), which is closely connected with the memoirs just mentioned, since it shows that the calcareous matter in that water is held in solution by the "fixed air" present and can be precipitated by lime.

In the north and west there are extensive mountain ranges of calcareous formation, intersected by deep ravines; while farther south the land is more level, and there are many fertile valleys.

The upper divisions consist of bituminous limestones, clay-slates, alum-slate, and contain numerous species of trilobites of the genera Paradoxides, Conocoryphe, Agnostus, Sphaerophthalmus, Peltura, &c. The Ordovician formation occurs in two distinct facies - the one shaley and containing graptolites; the other calcareous, with brachiopods, trilobites, &c. The most constant of the calcareous divisions is the Orthoceras limestone, a red or grey limestone with Megalaspis and Orthoceras.

These spaces make up the apparent body-cavity, the ta, Stomach of common crab, true body-cavity or coelom having Cancer pagurus, laid open, been, for the most part, obliter showing b, b, b, some of the ated by the great expansion of calcareous plates inserted in the blood-containing spaces.

The chalk and limestone plateaus are usually almost without inhabitants, and the villages of these districts occur grouped together in long strings, either in drift-floored valleys in the calcareous plateaus, or along the exposure of some favoured stratum at their base.

Beyond, again, lies a broad furrow, or ` longitudinal fold,' as geologists call it, parallel to the ridges, and then rises the last elevation, a belt of low calcareous hills, on which, here and there among the waves of beech forest, purple or blue with distance, a white cliff retains its local colour and shines like a patch of fresh snow.

In general the Upper Jurassic beds are much more calcareous on the north flank of the chain than they are on the south.

It has been shown that the best hydraulic lime, or volcanic puzzuolana and lime, if properly ground while slaking, and otherwise treated in the best-known manner, as well as some of the so-called natural (calcareous) cements, will yield results certainly not inferior to those obtained from Portland cement.

The hard calcareous substance to which the name coral is applied is the supporting skeleton of certain members of the Anthozoa, one of the classes of the phylum Coelentera.

The corallites are connected at intervals by horizontal platforms containing solenia, and at the level of each platform the cavity of the corallite is divided by a transverse calcareous partition, either flat or cup-shaped, called a tabula.

The skeleton of the Alcyonacea consists of separate calcareous spicules, which are often, especially in the Nephthyidae, so abundant and so closely interlocked as to form a tolerably firm and hard armour.

In the first-named the medulla is penetrated by solenia and forms an indistinct axis; in the remainder the medulla is devoid of solenia, and in the Melitodidae and Corallidae it forms a dense axis, which in the Melitodidae consists of alternate calcareous andhornyjoints.

It owes its commercial value to the beauty of its hard red calcareous axis which in life is covered by a cortex in which the proximal moieties of the zooids are imbedded.

The calcareous skeleton of the Pennatulacea consists of scattered spicules, but in one species, Protocaulon molle, spicules are absent.

All recent corals, as has already been said, conform so closely to the anatomy of normal Actinians that they cannot be classified apart from them, except that they are distinguished by the possession of a calcareous skeleton.

This skeleton is largely composed of a number of radiating plates or septa, and it differs both in origin and structure from the calcareous skeleton of all Alcyonaria except Heliopora.

Synapticulae are calcareous bars uniting adjacent septa.

As the buds develop the canal system becomes much extended, and calcareous tissue is deposited between the network of canals, the confluent edgezones of mother zooid and bud forming a coenosarc. As the process continues a number of calicles are formed, imbedded in a spongy tissue in which the canals ramify, and it is impossible to say where the theca of one corallite ends and that of another begins.

The soil of the greater part of the state consists of a drift deposit of loose calcareous loam, which extends to a considerable depth, and which is exceedingly fertile.

Originally the calcareous substance of the plates (stereom) was pierced by irregular canals, more or less vertical, and containing strands of the soft tissue (stroma) that deposited the stereom, as well as spaces filled with fluid.

The calcareous skeleton, which may be entirely absent, is usually in the form of minute spicules, sometimes of small irregular plates with no trace of a calycinal or apical system; to these is added a ring of pieces radiately arranged round the oesophagus.

The soil is calcareous; it was covered with scrub (chiefly the wild olive) until comparatively recent times, but this has been cut, and the rock is now bare.

Where the flints lie the chalk must have been dissolved away; we have in fact a kind of metasomatic replacement in which a siliceous rock has slowly replaced a calcareous one.

This flat surface is broken by two ranges of calcareous hills running north and south through the county, and known as the Lincoln Edge or Heights, or the Cliff, and the Wolds.

The mineral occurs in metalliferous veins in the lead mines of Strontian in Argyllshire, Pateley Bridge in Yorkshire, Braunsdorf near Freiberg in Saxony; abundantly in veins in calcareous marl near Minster and Hamm in Westphalia; and in limestone at Schoharie in New York.

The body is indistinctly segmented, and is enveloped in a fold of the integument, usually with calcareous plates.

During recent times the most destructive were those of, 8 r 1, 1820, 1840 and 1893; and, although the prevailing geological formations are sedimentary, chiefly calcareous, there seems no doubt that these disturbances are of igneous origin.

Even the most delicate tissues, such as cambium and phloem, the endosperm of seeds, or the formative tissue of the growing-point, are frequently preserved cell for cell, both in calcareous and silicious material.

The non-cellular order Siphoneae is fairly well represented in Palaeozoic strata, especially by calcareous verticillate forms referable to the family Dasycladeae; the separate tubular joints of the articulated thallus, bearing the prints of the whorled branches, are sometimes cylindrical (Arthroporella, Vermiporella, &c.), sometimes oval (Sycidium) or spherical (Cyclocrinus).

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.

A genus Zonatrichites, compared with species of Cyanophyceae, has been described as a Calcareous alga from Liassic limestones of Silesia.

Near volcanoes they contain many volcanic minerals, and around coral islands they are often in large part calcareous.

Some of them contain much iron (yellow, blue and red clays); others contain abundant calcium carbonate (calcareous clays and marls).

It is fine, tenacious and bright red, and represents the insoluble and thoroughly weathered impurities which are left behind when the calcareous matter is removed in solution by carbonated waters.

The type of coarse aggregate used included normal-weight calcareous and siliceous, and lightweight.

Calcareous beech and yew woodland forms perhaps 40% of the total amount of lowland beech and yew habitat type defined above.

Urea is used as a top dressing in Portugal, mainly calcareous soils.

This is due in part to the highly calcareous nature of some of the mineral sediments at the site.

At Spring Hill there is an area of slightly calcareous grassland.

Sefton Coast Sefton Sefton Coast is a large area of predominantly calcareous dune vegetation in northwest England.

Despite the generally calcareous environment, it is also possible that the samples contain pollen and diatom evidence.

Prolific ash regeneration is found on very calcareous soils that are often very steep.

All the pieces are white or white/grey patinated with some calcareous concretions on a number of pieces.

However, elsewhere in Europe calcareous fen is the species ' most typical habitat.

The moss Calliergon cuspidatum is characteristic of many calcareous flushes in the east midlands.

Management, research and guidance Management agreements to conserve calcareous grassland on SSSIs have been made between owners and occupiers and EN or CCW.

The cover of lowland calcareous grassland has suffered a sharp decline in extent over the last 50 years.

Upland calcareous grassland occurs on landslip material below the chalk cliffs; species include harebell, thyme, purging flax and early purple orchid.

The calcareous tube worm Serpula vermicularis forms twisting masses of tubes on the shell occupied by the hermit crab.

Examples include woodland clearings and rides, calcareous grassland, coastal landslips, abandoned quarries, disused railroad cuttings, and limestone pavements.

The skeletons of millions of aquatic animals, which lived and died in the lake, formed a layer of calcareous marl.

They are usually beds containing numbers of fossils of marine mollusks, the calcareous shells of which supply calcium.

The calcareous mudstones and limestones are rich in fossils.

Deepening of the sea in the later Cretaceous marked the onset of the deposition of large amounts of calcareous ooze on the sea-floor.

The communities develop on extensive crags of calcareous basalt, which provides a refugium for a rich calcicolous flora.

The habitat type is developed at high altitudes on calcareous schist.

The presence of calcareous bands within otherwise mainly siliceous rocks often brings the two types together on the same rock outcrop.

Chalk is a very pure form of limestone composed of countless millions of the minute calcareous skeletons of coccoliths, a form of algae.

Some species have calcareous spicules deposited in the tunic which would make them rather like eating gristle with sand embedded in it.

It tolerates a wide range of soil pH, being found on both mildly acidic and calcareous substrates.

I think Calcareous subjects, especially the optically transparent types work best.

They include fantastic rock formations, karst cliffs and caves and terraces of calcareous tufa.

The wooly willow is further restricted by its requirement for calcareous soils.

In many parts, particularly in the eastern basin, a calcareous or siliceous crust, from half an inch to three inches in thickness, is met with; and Natterer suggested that the formation of this crust may be due to the production of carbonate of ammonium where deposits containing organic matter are undergoing oxidation, and the consequent precipitation of carbonate of lime and other substances from the waters nearer the surface.

Thus an organized individual (tout organise) " is a composite body consisting of the original, or elementary, parts and of the matters which have been associated with them by the aid of nutrition "; so that, if these matters could be extracted from the individual (tout), it would, so to speak, become concentrated in a point, and would thus be restored to its primitive condition of a germ; " just as, by extracting from a bone the calcareous substance which is the source of its hardness, it is reduced to its primitive state of gristle or membrane."2 " Evolution " and " development " are, for Bonnet, synonymous terms; and since by " evolution " he means simply the expansion of that which was invisible into visibility, he was naturally led to the conclusion, at which Leibnitz had arrived by a different line of reasoning, that no such thing as generation, in the proper sense of the word exists in nature.

Others that are exceedingly productive are the black calcareous loam of the prairies, the calcareous silt of the bluff belt along the eastern border of the Delta, and the brown loam of the tableland in the central part of the state.

The shell of the Pulmonata, though always light and delicate, is in many cases a well-developed spiral " house," into which the creature can withdraw itself; and, although the foot possesses no operculum, yet in Helix the aperture of the shell is closed in the winter by a complete lid, the " hybernaculum," more or less calcareous in nature, which is secreted by the froot.

Helix hibernates in a torpid condition for about four months, and during this period the aperture of the shell is closed by a calcareous membrane secreted by the foot.

Where there is complete freedom from stagnant water in the ground, and abundant room for the spread of its branches to light and air, the larch will flourish in a great variety of soils, stiff clays, wet or mossy peat, and moist alluvium being the chief exceptions; in its native localities it seems partial to the debris of primitive and metamorphic rocks, but is occasionally found growing luxuriantly on calcareous subsoils; in Switzerland it attains the largest size, and forms the best timber, on the northern declivities of the mountains; but in Scotland a southern aspect appears most favourable.

The loess is a " salt, fine sandy loam with a large percentage of sand or silt, and considerable calcareous matter, and usually a small amount of clay."

Soils are calcareous and several ruderal species are restricted or at their greatest abundance here.

Current status The main habitat of the pale shining brown is scrubby grassland on light calcareous soils.

The willows are associated with an area of 6170 Alpine and subalpine calcareous grasslands on steep, rocky and remote ground.

A calcareous sedimentary deposit, with recent shells, altered by the contact of superincumbent lava, its horizontality and extent.

The site is enhanced by a small area of upland calcareous grassland on its margin with LCA 121.

Alpina, angustifolia, Clusii, and Kochiana, which thrive best in calcareous soils, except the last, which requires a soil free of it.

A choice plant for the select bulb garden or rock garden, but dies out in heavy soil, thriving in calcareous soils.

In cultivation they ask for nothing more than a sunny garden or position, while revelling in light sandy or calcareous loam; indeed, in common with all the Flag Iris, they much appreciate a limy soil.

It is usually considered difficult to grow, but it may be easily kept on dry banks in the rock garden in a firm bed of calcareous soil, or of loam mixed with broken limestone.

The compost should consist mainly of good loam, to which a small proportion of peat may be added, and which should be free from calcareous matter.

It is suited for warm ledges on the rock garden in well-drained sandy or calcareous soil.

It grows almost anywhere, but prefers dry, calcareous soils.

Other plants occur indifferently both on calcareous and on non-calcareous soils.

Again, acidic humus does not form in calcareous soils; and hence one does not expect to find plants characteristic of acidic peat or humus on calcareous soils.

Whether the closed primitive shell-sac of the slugs (and with it the transient embryonic shell-gland of all other Mollusca) is precisely the same thing as the closed sac in which the calcareous pen or shell of the Cephalopod Sepia and its allies is formed, is a further question which we shall consider when dealing with the Cephalopoda.

The calcareous Claiborne or ClaiborneLisbon formation-group lies south of the last, in a wedge-like strip with the apex on the Alabama boundary; it is a series of clays and sands, richly fossiliferous.