Fresh-water Sentence Examples

The fisheries are all fresh-water, principally white-fish, pickerel and pike.

This genus comprises fresh-water polyps of simple structure.

Fresh-water pearls of considerable value and beauty are found in the Red Cedar river.

Suez is supplied with water by the fresh-water canal, which starts from the Nile at Cairo and is terminated at Suez by a lock which, north of the town, joins it to the gulf.

Aspidogaster conchicola is a form not uncommon in Anodon, Unio and certain fresh-water Gastropods.

Fish taken in the lakes include perch, pike, char and trout in Windermere, Ennerdale, Bassenthwaite, Derwentwater, &c., and the gwyniad or fresh-water herring in Ullswater.

The manatee, or sea-cow, frequents the mouths of rivers, the sargasso drifts, and the regions of submarine fresh-water springs off the coast.

Molluscs are common on the coasts, including the pearl oyster, and in the fresh-water streams and lakes.

Caryophyllaeus mutabilis occurs in the roach and other fresh-water fish, and passes its earlier stages of development in fresh-water Oligochaets (Tubifex).

The larvae usually live in Molluscs, the mature worm in vertebrates, and the immature but metamorphosed Trematode in either host and also in pelagic and littoral marine and fresh-water invertebrates.

The fresh-water fauna also contains a representative of the Entoprocta (Urnatella), two or three Ctenostomes, such as Victorella and Paludicella, and one or two species of Cheilostomata.

Of the fresh-water tortoise there are two kinds, the nippon (Tnionyx japonica) and the kame-no-ko (Ernys vulganisjaponica).

The honeycomb of rock, and capillary action, retard the lighter fresh-water from sinking to the sea; the soakage from rain has therefore to move horizontally, over the strata about sea-level, seeking outlets.

Among the manufactures are beer, wagons, wool, and pearl buttons, and the city is a centre of the fresh-water pearl fisheries along the Mississippi.

The island is fertile, but lacks fresh water.

The occasional development of wings is probably of service to the species in enabling the insects to reach new fresh-water breeding-grounds.

The importance of the osmotic pressure of sea-water in biology will be easily understood from the fact that a frog placed in sea-water loses water by exosmosis and soon becomes 20% lighter than its original weight, while a true salt-water fish suddenly transferred to fresh water gains water by endosmosis, swells up and quickly succumbs.

Unfortunately no observations of evaporation from the surface of the open sea have been made and very few comparisons of the evaporation of salt and fresh water are on record.

The fact that sea-water does evaporate more slowly than fresh water has been proved by the observations of Mazelle at Triest and of Okado in Azino (Japan).

The fresher enclosed seas include the Malay and the East Asiatic fringing seas with 30 to 34.5 per mille, the Gulf of St Lawrence with 30 to 31, the North Sea with 35 north of the Dogger Bank diminishing to 32 further south, and the Baltic, which freshens rapidly from between 25 to 31 in the Skagerrak to 7 or 8 eastward of Bornholm and to practically fresh water at the heads of the Gulfs of Bothnia and Finland.

The artificial propagation and preservation of salmon and other edible fresh-water fish have been carried on successfully under the supervision of a state commission.

Lake Xochimilco, celebrated for its chinampas, or "floating gardens,", is supplied very largely by fresh-water springs opening within the lake itself, which the city has partially diverted for its own water supply.

For the water supply the Aztecs used the main causeway through their city as a dam to separate the fresh water from the hills from the brackish water of Texcoco, and obtained drinking water from a spring at the base of the hill of Chapultepec. The Spaniards added three other springs to the supply and constructed two long aqueducts to bring it into the city.

The first two are migratory, entering rivers in the spring to spawn; of the river-lamprey, however, specimens are met with in fresh water all the year round.

This is all the more unfortunate as eels were the only large edible creatures found in the fresh-water lakes and rivers.

They are for the most part marine in habitat, but a familiar fresh-water form is the common Hydra of ponds and ditches, which gives origin to the name of the class.

The families occupy fresh water as well as the sea.

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.

Medusae are exclusively aquatic animals and for the most part marine, but at least two fresh-water species are known.'

Another fresh-water form is Limnocnida tanganyicae, discovered first in lake Tanganyika, and now known to occur also in the Victoria Nyanza and in the Niger.

The city is supplied with fresh water by means of an aqueduct carried by arches over an extensive valley.

The Rotifera are all aquatic, the majority dwelling in fresh water with Protozoa and Protophyta, as well as Entomostracous Crustacea.

In many parts of south-eastern Asia, in Mauritius, in North and South Africa, in Madagascar, in the Azores, it has become thoroughly acclimatized, and successfully competes with the indigenous fresh-water fishes.

It often feeds on fresh-water turtles; sometimes following the reptiles into the water to effect a capture, it inserts a paw between the shells and drags out the body of the turtle by means of its sharp claws.

The Golfo Dulce is, as its name implies, a fresh-water lake, although so near the Atlantic. It is about 36 m.

The lakes of Ontario and Manitoba produce white fish, sturgeon and other fresh-water fish.

They resemble the May-flies in their " hemimetabolous " lifehistory; the young insects are markedly unlike their parents, inhabiting fresh water and breathing dissolved air, either through tracheal gills at the tip of the abdomen, or by a branching system of air-tubes on the walls of the rectum into which water is periodically admitted.

The king in 1440 granted the burgesses Hessle, North Ferriby and other places in order that they might obtain a supply of fresh water.

Over seventy varieties of seaweeds, growing in the fresh-water pools and in the waters near the coast, are used by the natives as food.

Boepple, a German, the buttons being made from the shells of the fresh-water mussel found in the neighbourhood; and there are other manufactures.

Salt and fresh-water lakes are intermingled.

The stratified rocks of this system include marine limestones, shales and sandstones; estuarine, lagoonal and fresh-water shales, sandstones and marls with beds of coal, oil-bearing rocks, gypsum and salt.

In point of fact, however, the entire volume of fresh water poured into the Caspian is only just sufficient to compensate for the loss by evaporation.

Fresh-water lakes, one of which, Deal Lake, extends for some distance into the wooded country, form the northern and southern boundaries.

The Ismailia or Fresh-water canal branches from the Nile at Cairo and follows, in the main, the course of the canal which anciently joined the Nile and the Red Sea.

The existing canal was dug in 1863 to supply fresh water to the towns on the Suez Canal.

They occur also abundantly in the shallows of rivers and fresh-water lakes, and in less number in salt lakes and in the sea; such aquatic Angiosperms are not, however, primitive forms, but are derived from immediate land-ancestors.

Generally speaking this salt, which may contain up to 15% of impurities, goes into commerce just as it is, but in some cases it is taken first to the refinery, where it either is simply washed and then stove-dried before being sent out, or is dissolved in fresh water and then boiled down and crystallized like white salt from rock-salt brine.

Through this space the fresh surface water finds its way, and dissolving the salt below rises in the inner tube as brine, but only to such a level that the two columns bear to one another the relation of ten to twelve, this being the inverse ratio of the respective weights of saturated brine and fresh water.

The fish of Lake Aral belong to fresh-water species, and in some of its rapid tributaries the interesting Scaphirhynchus, which represents a survival from the Tertiary epoch, is found.

The majority of the species belong to the sea, but many are found in fresh water.

The vesicles of Fucaceae and Laminariaceae prevent the sinking of the bulkier forms. But why certain Fucaceae favour certain zones in the littoral region, why certain epiphytes are confined to certain hosts, why Red and Brown Algae are not better represented in fresh water or Green Algae in salt, - these are problems to which it is difficult to find a ready answer.

Glen lakes are almost wholly confined to the western half of the Highlands, where they form the largest sheets of fresh water.

The largest sheets of fresh water in the Lowlands are lakes of the plains as Loch Leven and the Lake of Menteith.

It is built on a branch of the Fresh Water or Ismailia canal, and on the Al-Mo`izz canal (the ancient Tanitic channel of the Nile), and is 47 m.

The only fresh-water fish is the eel.

There are 67 species of birds known from Sokotra, of which 15 are endemic; of 22 reptiles, 3 genera and 14 species are peculiar; and of the land and fresh-water shells, to whose distribution great importance attaches, 44 species out of 47 are confined to the island.

All the salt-water snakes in India are poisonous, while the fresh-water forms are wholly innocuous.

Fresh-water and marine molluscs are also very numerous.

It is thus the largest sheet of fresh water between Lake Michigan and Lake Titicaca on the borders of Bolivia and Peru.

The chief business is in stock of every kind, dairy and agricultural produce and fresh-water fish, a large quantity of which is exported to France.

From a broad avenue on the upper side downward to the west slope the streets, through which run streams of cool, fresh water from the mountains above.

It is now represented in all seas and lands, in fresh-water lakes and streams, and even in warm springs.

The fisheries, both fresh-water and sea, are important, and fall for consideration as an industry.

Pearls are sometimes found in the fresh-water mussel (Margaritana margaritifera); thus a tributary of the Lilla Lule River takes its name, Perle River, from the pearls found in it.

In the extreme south are Lagoa Blanca, a large fresh-water lake in lat.

The hippopotamus, manatee, crocodile and beaver are found in the rivers, and both land and fresh-water tortoises are common.

The Jurassic deposits are partly marine and partly fresh-water or terrestrial, including beds of lignite.

Towards the north these are associated with fresh-water limestones, indicating the presence of land in that direction.

Salmon, lampreys and eels are caught in some of the larger rivers; trout abound in the streams of the northern provinces; but many fresh-water fish common elsewhere in Europe, including pike, perch, tench and chub, are not found.

In fresh-water culture the eggs thus fertilized may be at once distributed to the waters to be stocked, or they may be kept in special receptacles provided with a suitable stream of water until the fry are hatched, and then distributed, or again they may be reared in the hatchery for several months until the fry are active and hardy.

The hatching of eggs, whether of fresh-water or salt-water fishes, presents no serious difficulties, if suitable apparatus is employed; but the rearing of fry to an advanced stage, without serious losses, is less easy, and in the case of sea-fishes with pelagic eggs, the larvae of which are exceedingly small and tender, is still an unsolved problem, although recent work, carried out at the Plymouth laboratory of the Marine Biological Association, is at least promising.

In fresh-water culture little advantage, if any, has been found to result from artificial hatching, unless this is followed by a successful period of rearing.

Coalbearing clays containing fresh-water molluscs and dicotyledonous plants, as also conglomerates, alternate with the sandstones in these Tertiary deposits.

The eggs are spawned in May and June, and are similar in the two species; they are heavier than the fresh water in which they develop, but unlike the herring's eggs they are not adhesive.

Among fishes, white fish, lake trout, perch, herring, sun-fish, bass, sturgeon, pickerel, suckers, German carp and fresh-water drum abound in the lakes.

The fresh-water fish caught in the Great Lakes by residents in Michigan exceed in value those caught by residents of other states, and in 1907 the catch was valued at $1,806,767.

It is not obvious why these fresh-water forms have been associated popularly with the Mytilacea under the name mussel, unless it be on account of the frequently very dark colour of their shells.

Mytilus possesses no siphonal tube-like productions of the margin of the mantle-skirt, nor any notching of the same, representative of the siphons which are found in its fresh-water ally, the Dreissensia polymorpha.

Experiments made by removing mussels from salt water to brackish, and finally to quite fresh water show that it is even more tolerant of fresh water than the oyster; of thirty mussels so transferred all were alive after fifteen days.

The fresh-water Mussels, Anodonta cygnea, Unio pictorum, and Unio margaritiferus belong to the order Eulamellibranchia of Lamellibranch Molluscs, in which the anterior and posterior adductor muscles are equally developed.

A vast number of species arranged in several genera and sub-genera have been distinguished, but in the British Islands the three species above named are the only claimants to the title of "fresh-water mussel."

Most of them inhabit the sea, but representatives of all the chief groups are found in fresh water (though the Cirripedia have hardly gained a footing there), and this is the chief home of the primitive Phyllopoda.

In 1701 William Dampier was wrecked on its coast, and during his detention discovered the only spring of fresh water the island contains.

Three coecilians, three batrachians (including a mountain-frequenting frog) and three fresh-water crustaceans are also indigenous, and about twenty-six species of land shells.

The crust of the earth, so far as it is permeable and above the sea-level, receives from rainfall its supply of fresh water.

On the upheaval of such rocks above the sea-level, fresh water from rainfall began to flow over their exposed surfaces, and, so far as the strata were permeable, to lie in their interstices upon the salt water.

A hill, as it were, of fresh water rested in the interstices of the rock upon the salt water, and continuing to press downwards, forced out the salt water even below the level of the sea.

Subject to the rock being porous this process would be continued until the greater column of the lighter fresh water balanced the smaller head of sea water.

On such an island, in the centre of which a borehole is put down, brackish water may be reached far below the sea-level; the salt water forming a saucer, as it were, in which the fresh water lies.

Such a saltwater saucer of fresh water is maintained full to overflowing by the rainfall, and owing to the frictional resistance of the sand and to capillary action and the fact that a given column of fresh water is balanced by a shorter column of sea water, the fresh water never sinks to the mean sea-level unless artificially abstracted.

For small supplies such a well may be perfectly successful; but however small the quantity drawn, it must obviously have the effect of diminishing the volume of fresh water, which contributes to the maintenance of the level of saturation above the sea-level; and with further pumping the fresh water would be so far drawn upon that the mean level of saturation would sink, first to a curved figure - a cone of depression - such as that represented by the new level of saturation dd, and later to the figure represented by the lines ee, in which the level of saturation has everywhere been drawn below the mean sea-level.

Before this stage the converse process begins, the reduced column of fresh water is no longer capable of balancing the sea water in the sand, inflow occurs at c and e, resulting finally in the well water becoming saline.

Into such blocks, charged with salt crystals and thoroughly dried, fresh water was then passed, and precisely the converse process took place.

If it exceeds this, the stock of fresh water held in the interstices of the rock, and capable of flowing towards the well, must disappear; and the deficit between the supply and demand can only be made up by water filtering from the sea and reaching the well at first quite free from salt, but sooner river water whatever.

Among the fresh-water lakes of the world it is exceeded in size by Lake Superior only and has an area of over 26,000 sq.

Probably the northern and north-eastern region, within the monsoon area, contains relatively fresh water down to very considerable depths.

That the Baltic Stream must be a surface current, because it originates from a redundancy of fresh water.

There is only a single spring of fresh water on the island, and that in a position difficult of access.

Immense fresh-water lakes, in which were deposited layers of plants (now yielding coal), filled up the depressions of the country.

The order contains about fifty species in fifteen genera, twelve of which occur in fresh water while three are marine; and includes both floating and submerged forms. Hydrocharis floats on the surface of still water, and has rosettes of kidney-shaped leaves, from among which spring the flower-stalks; stolons bearing new leafrosettes are sent out on all sides, the plant thus propagating itself in the same way as the strawberry.

The order is a widely distributed one; the marine forms are tropical or subtropical, but the fresh-water genera occur also in the temperate zones.

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

On the eastern side of Madagascar the contest between the fresh water of the rivers and the sea has caused the formation of a chain of lagoons for nearly 300 m.

The crater of the central cone contains a fresh-water lake about 150 yds.

Ice forms over fresh water if the temperature of the air has been for a sufficient time at or below the freezing-point; but not until the whole mass of water has been cooled down to its point of maximum density, so that the subsequent cooling of the surface can give rise to no convection currents, is freezing possible.

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.

They are divisible into two great series, according to their mode of origin in the sea or in fresh-water.

These sheets of fresh-water covered the centre of the country,including the basins of the Ebro,Jflcar, Guadalaviar, Guadalquivir arid Tagus.

The island is watered by several short rivers, mainly on the east and south; there are numerous fresh water springs, as well as hot chalybeate and sulphurous springs.

The Bad Lands are essentially nothing but fresh-water mud excessively weathered and eroded.

The majority are marine; but some genera (Ceratium, Peridinium) include fresh-water species.

Why the Thyrostraca, so hardy, so widely dispersed and multitudinous, and with a history so prolonged, should not have made more extended and more independent incursions into fresh water remains a problem.

The absence of vegetation on its shores, due to the scanty rainfall and general want of fresh water - except in the neighbourhood of springs like `Ain Feshkhah and `Ain Jidi, where a luxuriant subtropical vegetation is found - accounts for the story that no plant could live in the poisonous air which broods over the sea.

It is usually regarded as beginning with a fresh-water series containing the remains of fish and labyrinthodonts; but as it also contains Vertebraria it is probably Palaeozoic; and this series is covered by sandstones and shales which are probably of Triassic age.

In India the same flora occurs in a thick series of fresh-water sediments, known as the Lower Gondwana system, including basal boulder-beds like those of Australia.

Plants, on the other hand, like land and fresh-water animals, occupied areas which may or may not have been continuous.

It may be said that, on the whole, the distribution of the batrachians agrees to some extent with that of fresh-water fishes, except for the much less marked affinity between South America and Africa, although even among the former we have the striking example of the distribution of the very natural group of the aglossal batrachians, represented by Pipa in South America and by Xenopus and Hymenochirus in Africa.

The speakers waxed lyrically about the fresh water aquatic conservation center, which they hope to bring to a disused clay pit near Bedford.

Known as confined aquifers, they are pools of fresh water trapped in permeable rock strata at depths of 300 to 6,000 feet.

The water in these ditches is often brackish - a mixture of salt and fresh water.

This extra cold fresh water could halt the overturning circulation, stopping all this extra heat reaching Northern Europe.

Known not only for its water birds but also for its fresh water crayfish population.

Clearly enthused by the subject matter, Brownlow wants to inspire more divers to explore fresh water.

With custom built IT desks and relaxing study areas where you can enjoy an espresso or simply a glass of fresh water.

Not only do the flamingoes need food but they need fresh water too.

Fishing; deep sea and shark, and fresh water fly-fishing at local reservoirs, is also available.

Merlin's marine biologist declared the Powan " A fresh water herring that is pretty unique to Loch Lomond.

Ironically the infestation of barnacles on yacht hulls - which the paint was designed to prevent - does not happen in fresh water.

With the constant influx of fresh water from the Atlantic Ocean, Gibraltar enjoys teeming marine life in a vibrant display of colors.

Viviparous adult females release L1 larvae into fresh water.

Mother-of-Pearl Iridescent, milky interior shell of the fresh water mollusk that is sliced thin and used on watch dials.

A particularly noteworthy feature at the site is the network of interlocking clay pipes which carried fresh water supplies around the abbey.

The next day, place the soaked peas in fresh water to cover and cook until tender, about 3 hours.

The father decides to build a pipeline to bring fresh water to their rustic home.

Does salt water or fresh water make onion skins more pliable?

Of special interest was a little ringed plover on the salt marsh, a bird more associated with fresh water habitats.

There are marine rotifers, but the vast majority occur in fresh water.

The juvenile shad can spend up to 2 years in the fresh water before heading out to sea.

Natterjack toads breed in the fresh water pools in the sand dunes.

The term turtle is usually used for the aquatic species, aquatic fresh-water turtles also being referred to as terrapins.

They are divisible into the Haplodrili or Archiannelida, the Polychaeta containing the marine worms, the Oligochaeta or terrestrial and fresh-water annelids (see Earthworm), the Hirudinea or leeches (see Leech), and a small group of parasitic worms, the 11-Tyzostomida (q.v.).

As is very frequently the case with marine forms, as compared with their fresh-water and terrestrial allies, the Polychaeta differ from the Oligochaeta and Hirudinea in possessing a free living B FIG.

While a number of fresh-water, or in some cases brackish, lakes each less than ioo sq.

Large coarse algae, such, for instance, as the Fucaceae and Laminariae, do not readily adhere to paper, and require soaking for some time in fresh water before being pressed.

There are a score of fresh-water ponds, the largest being Hummock (320 acres).

As for the land and fresh-water molluscs, some 200 of which are known, they are mainly kindred with those of China and Siberia, tropical and Indian forms being exceptional.

Lake Xochimilco, celebrated for its chinampas, or " floating gardens" (see Mexico, Federal District Of), is supplied very largely by fresh-water springs opening within the lake itself, which the city has partially diverted for its own water supply.

Large tortoises abound, and, in the `Ain el-'Arus pool, fresh-water turtles and carp. Of domestic Ritter, Erdkunde, xi.

In the S.E., where the low, flat Coastal Plain is poorly drained, is the Great Dismal Swamp, a fresh-water marsh covering 700 sq.

Fish includes products caught or farmed n fresh water like trout, bass and catfish.

Water Makers- A device that converts seawater into drinkable fresh water.

Next, place the raw liver in a one quart stock pot, and add enough chicken broth and fresh water to cover the raw livers with two inches of water.

Remember, do not do this when it is too cold or too hot for your cats to be comfortable, and always have plenty of fresh water for them to drink.

All animals need a constant supply of fresh water.

Providing food, fresh water and kitty litter are all very important parts of cat care.

Topics include fresh water and clean air, and how to go about ensuring these are abundant.

Humans would be at risk as well, since the fresh water supply and ability to grow food could be impaired.

These elements included total energy usage, fossil fuel usage, municipal solid waste, greenhouse gas emissions, and fresh water usage.

Once a healthy food source, seafood and fresh water fish are often dangerous to eat due to mercury and other harmful and deadly chemicals found in randomly tested fish and seafood.

Come summer, you will want to rinse your ski bindings with fresh water in order to remove the accumulated salt, dirt and debris.

However, fresh water pearl designs like drop earrings or a single pearl necklace are good choices.

Your dog will always have fresh water available and will usually receive a healthy treat to ward off hunger.

Always keep fresh water available for your pet.

I always keep two fresh bowls of water upstairs in the kitchen on the tile floor, and two bowls of fresh water downstairs on a hard wood floor.

Keep plenty of fresh water with you at all times when camping or hiking.

They need to be soaked in fresh water until they have absorbed the maximum amount of water required to hydrate them.

Clean, Fresh Water - In a tanked system, water is held in a tank where rust and scale eventually build up on the inside of the tank.

With a tankless water heater, the hot water is on-demand so you're always guaranteed clean, fresh water for every use.

Today, the advent of cultured and fresh water pearls means that pearl jewelry is more accessible, however, this does not detract from the beauty of a pearl however it has been formed.

Bracelets of fresh water pearls and sterling silver beads make a delicate combination in this beautiful mother and daughter set.

The Fine Jewelry collection uses 18K gold and fresh water pearls, as well as other precious gemstones.

Always bring a bottle of fresh water for continuous sipping.

Cattle must have access to clean, fresh water at all times.

Drain the water out of both the water heater and the fresh water tank.

Find the fresh water inlet line and screw the air adapter onto it.

Pull the water line running between the fresh water tank and fresh water pump out at the tank end.

The levels of naturally occurring fluoride in fresh water range from less than 0.1 ppm to more than 13 ppm.

Feel the sprinkle of fresh water along with the soothing trickle from the significant fountain central to the concourse area.

Frequent partial water changes are also necessary, but make sure you use chlorine remover each time you add fresh water.

Be sure the stand has fresh water in it daily.

It uses the pressure of clean water to circulate through your entire pool, allowing fresh water to be spread throughout without the use of excessive chemicals.

Lots of fresh water to keep the kidneys in good working order.

For example, if you weigh 140 pounds, you'll want to consume at least 140 ounces of fresh water.

A variety of sushi rolls are offered to visitors, including avocado or vegetable rolls, tempura appetizers, as well as sushi rolls that contain salmon, yellowtail fish, shrimp and fresh water eel.

The park offers fresh water fishing, several baseball fields and basketball courts.

Alex and Bill had run a water line to the hutches, so they had a constant supply of fresh water.

This untoward disaster led to the abandonment of the expedition, which forthwith returned to Spain, bringing with them the news of the discovery of a fresh-water sea.

The porous soil absorbs the moisture, and fresh water is scarce.

These are opposite to the large estuaries of the Queensland rivers, and might be thought to have been caused by fresh water from the land.

The most valuable fish taken was walleyed pike, and the catch of this fish and of pickerel from Lake Champlain in 1902 exceeded in value that from any other body of fresh water in the United States excepting Lake Huron and Lake Erie.

Fresh-water forms, however, are also known, very few as regards species or genera, but often extremely abundant as individuals.

In the British fresh-water fauna only two genera, Hydra and Cordylophora, are found; in America occurs an additional genus, Microhydra.

In fresh-water Hydromedusae the life-cycle is usually secondarily simplified, but in marine forms the life-cycle may be extremely complicated, and a given species often passes in the course of its history through widely different forms adapted to different habitats and modes of life.

The manubrium is absent altogether in the fresh-water medusa Limnocnida, in which the diameter of the mouth exceeds half that of the umbrella; on the other hand, the manubrium may attain a great length, owing to the centre of the sub-umbrella with the stomach being drawn into it, as it were, to form a long proboscis, as in Geryonia.

The sub-order includes the family Hydridae, containing the common fresh-water polyps of the genus Hydra.

Polypodium hydriforme Ussow is a fresh-water form parasitic on the eggs of the sterlet.

Of doubtful position, but commonly referred to the Trachylinae, are the two genera of fresh-water medusae, Limnocodium and Limnocnida.

In this connexion must be mentioned, finally, the medusae budded from the fresh-water polyp Microhydra.

Although many plants typical of fresh water are able to grow also in brackish water, there are only a few species which appear to be quite confined to the latter habitats in this country.

In the case of land and fresh-water organisms the sea is the chief barrier; in the case of marine organisms, the land.

The log should be washed in fresh water when practicable, to prevent oxidization of the wheels, and be lubricated with suitable oil through a hole in the case.

Fine crystals occur at Conil near Cadiz; whilst in the province of Teruel in Aragon, sulphur in a compact form replaces fresh-water shells and plant-remains, suggesting its origin from sulphur-springs.

The fresh-water fish seem in their affinities to be nearly allied to those of the Niger and the Nile.

Some fly through the air, others burrow in the earth, while several families have become fully adapted to life in fresh water.

The Hexapoda, being aerial, terrestrial and fresh-water animals, are but occasionally preserved in stratified rocks, and our knowledge of extinct members of the class is therefore fragmentary, while the description, as insects, of various obscure fossils, which are perhaps not even Arthropods, has not tended to the advancement of this branch of zoology.

In process of time some of these banks, as in the case of Venice, raised themselves above the level of the water and became the true shore-line, while behind them lay large surfaces of water, called lagoons, formed partly by the fresh water brought down by the rivers, partly by the salt-water tide which found its way in by the channels of the river mouths.

They occur up mountain slopes as far as vegetation extends, in tropical valleys and forests, in open grassy plains, in sandy deserts, and even in fresh-water ponds and between tide-marks on the seashore.

This deviation is the adoption of an aquatic mode of life by the European fresh-water spider (Argyroneta) and by the marine spider Desis, which is found on the shores of the Indian and Pacific Oceans from Cape Colony to eastern Australia.

The fresh-water spider (Argyroneta) lives amongst the weeds of lakes and ponds and, like Desis, is quite at home beneath the water either swimming from spot to spot or crawling amongst the stems of aquatic plants.

The Pliocene deposits are not very widely spread and are generally of fresh-water origin excepting near the coast, but marine Pliocene beds have been found at el Forklus in the Palmyra desert.

There are a few species of fresh-water fish, but food-fishes are scarce both in the rivers and along the coast.

The fresh-water snails which are not Pulmonates are the Paludinidae, Valvatidae and Ampullaridae, together with Neritina, a genus of the Neritidae.

Of fresh-water fish the lisa, dogro, guayacbn and viajocos (Chromis fuscomaculatus) are possibly the most noteworthy.

It is also the largest market for fresh-water fish in America, and handles large quantities of lumber and grain.

The docks are provided with gas and electric lights, 18 steam cranes for loading and discharging vessels, a triple line of railway and a supply of fresh water.

The silica, in the form of diatom or radiolarian skeletons, is eventually deposited on the ocean floor after the death of the organisms. Most of the fine colloidal clay is, however, deposited as river-sludges when the fresh water carrying it mixes with denser sea-water.

Coal occurs in many Jurassic fresh-water;basins, namely, on the outskirts of the Altai, in south Yeniseisk, about Irkutsk, in the Nerchinsk district, at many places in the Maritime province, and on the island of Sakhalin.

They are usually found amongst seaweed in temperate seas, but they are probably widely distributed; some are fresh-water.

The Amazon is also the home of one of the largest fresh-water turtles known, the Emys amazonica, locally called the jurara-assu or tartaruga grande.

Coal is known to exist to the southeast of Kobdo, in the Tannu-ola, and in the basin of the Yenisei, but its age is unknown (fresh-water Jurassic ?).

Van Beneden, Claparede, and Allman, who during the 19th century approached the study of the lower marine organisms in the same spirit as that in which Trembley and Schaffer in the 18th century, and Swammerdam in the 17th, gave themselves to the study of the minute fresh-water forms of animal life.

Small springs of fresh water are frequent and there are 'several shallow lakes or pans - flat bottomed depressions with no outlet.

The river is well stocked with fish, both salt-water and fresh-water species being found in its waters, and several varieties of fresh-water fish in its tributaries.

The latter is a fresh-water lake of about 30 m.

Close to it is a watch-tower and a spring of fresh water.

The genuine Isopoda are divided among the Flabellifera, in which the terminal segment and uropods form a flabellum or swimming fan; the Epicaridea, parasitic on Crustaceans; the Valvifera, in which the uropods fold valve-like over the branchial pleopods; the Asellota, in which the first pair of pleopods of the female are usually transformed into a single opercular plate; the Phreatoicidea, a fresh-water tribe, known as yet only from subterranean waters in New Zealand and an Australian swamp nearly 6000 ft.

In the brackish waters of the east coast sea fish are found, together with pike, perch and other fresh-water forms. The crayfish is common in many places in central and southern Sweden.

It is recognized that the great fertility of fishes is nature's provision to meet a high mortality - greater in sea-fishes with minute pelagic eggs than in fresh-water fishes with larger-yolked eggs, partly because of the greater risks of marine pelagic life, and partly because of the greater delicacy of marine larvae at the time of hatching.