Australia the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands. It is the world's sixth-largest country by total area; the neighbouring countries are Papua New Guinea and East Timor to the north. The population of 25 million is urbanised and concentrated on the eastern seaboard. Australia's capital is Canberra, its largest city is Sydney; the country's other major metropolitan areas are Melbourne, Brisbane and Adelaide. Australia was inhabited by indigenous Australians for about 60,000 years before the first British settlement in the late 18th century, it is documented. After the European exploration of the continent by Dutch explorers in 1606, who named it New Holland, Australia's eastern half was claimed by Great Britain in 1770 and settled through penal transportation to the colony of New South Wales from 26 January 1788, a date which became Australia's national day; the population grew in subsequent decades, by the 1850s most of the continent had been explored and an additional five self-governing crown colonies established.
On 1 January 1901, the six colonies federated. Australia has since maintained a stable liberal democratic political system that functions as a federal parliamentary constitutional monarchy, comprising six states and ten territories. Being the oldest and driest inhabited continent, with the least fertile soils, Australia has a landmass of 7,617,930 square kilometres. A megadiverse country, its size gives it a wide variety of landscapes, with deserts in the centre, tropical rainforests in the north-east and mountain ranges in the south-east. A gold rush began in Australia in the early 1850s, its population density, 2.8 inhabitants per square kilometre, remains among the lowest in the world. Australia generates its income from various sources including mining-related exports, telecommunications and manufacturing. Indigenous Australian rock art is the oldest and richest in the world, dating as far back as 60,000 years and spread across hundreds of thousands of sites. Australia is a developed country, with the world's 14th-largest economy.
It has a high-income economy, with the world's tenth-highest per capita income. It is a regional power, has the world's 13th-highest military expenditure. Australia has the world's ninth-largest immigrant population, with immigrants accounting for 26% of the population. Having the third-highest human development index and the eighth-highest ranked democracy globally, the country ranks in quality of life, education, economic freedom, civil liberties and political rights, with all its major cities faring well in global comparative livability surveys. Australia is a member of the United Nations, G20, Commonwealth of Nations, ANZUS, Organisation for Economic Co-operation and Development, World Trade Organization, Asia-Pacific Economic Cooperation, Pacific Islands Forum and the ASEAN Plus Six mechanism; the name Australia is derived from the Latin Terra Australis, a name used for a hypothetical continent in the Southern Hemisphere since ancient times. When Europeans first began visiting and mapping Australia in the 17th century, the name Terra Australis was applied to the new territories.
Until the early 19th century, Australia was best known as "New Holland", a name first applied by the Dutch explorer Abel Tasman in 1644 and subsequently anglicised. Terra Australis still saw occasional usage, such as in scientific texts; the name Australia was popularised by the explorer Matthew Flinders, who said it was "more agreeable to the ear, an assimilation to the names of the other great portions of the earth". The first time that Australia appears to have been used was in April 1817, when Governor Lachlan Macquarie acknowledged the receipt of Flinders' charts of Australia from Lord Bathurst. In December 1817, Macquarie recommended to the Colonial Office. In 1824, the Admiralty agreed that the continent should be known by that name; the first official published use of the new name came with the publication in 1830 of The Australia Directory by the Hydrographic Office. Colloquial names for Australia include "Oz" and "the Land Down Under". Other epithets include "the Great Southern Land", "the Lucky Country", "the Sunburnt Country", "the Wide Brown Land".
The latter two both derive from Dorothea Mackellar's 1908 poem "My Country". Human habitation of the Australian continent is estimated to have begun around 65,000 to 70,000 years ago, with the migration of people by land bridges and short sea-crossings from what is now Southeast Asia; these first inhabitants were the ancestors of modern Indigenous Australians. Aboriginal Australian culture is one of the oldest continual civilisations on earth. At the time of first European contact, most Indigenous Australians were hunter-gatherers with complex economies and societies. Recent archaeological finds suggest. Indigenous Australians have an oral culture with spiritual values based on reverence for the land and a belief in the Dreamtime; the Torres Strait Islanders, ethnically Melanesian, obtained their livelihood from seasonal horticulture and the resources of their reefs and seas. The northern coasts and waters of Australia were visited s
Melaleuca leucadendra known as weeping paperbark, long-leaved paperbark or white paperbark is a plant in the myrtle family, Myrtaceae and is widespread in northern Australia, Southeast Asia, New Guinea and the Torres Strait Islands. It is a tree, sometimes growing to more than 20 m with a trunk covered with thick, papery bark and weeping thinner branches, it has a long flowering season, can flower at any time of the year and is grown as a tree in parks and on roadsides. It was the first melaleuca to be was described from a specimen growing in Indonesia. Melaleuca leucadendra is a large tree less than, but sometimes more than 20 m tall, its thick bark is papery white but pinkish or cream and it has weeping branches. Its leaves and young branches are covered with fine, white hairs when young but become glabrous as they mature; the leaves are arranged alternately, 75–270 mm long, 6.5–40 mm wide, narrow egg-shaped or lance-shaped and tapering to a point. The leaves have 5 longitudinal veins and are curved or sickle-shaped.
The flowers are cream, white or greenish-white and are arranged in spikes on the ends of branches which continue to grow after flowering, sometimes on the sides of branches or in the upper leaf axils. Each spike is up to 35 mm in diameter, up to 80 mm long and contains between 7 and 22 groups of flowers in threes; the petals fall off soon after the flower opens. The stamens are arranged in five bundles around the flower and each bundle contains 5 to 12 stamens. Flowering can occur at any time of the year and is followed by fruit which are woody capsules, 3.9–4.9 mm long in loose clusters along the stems. Melaleuca leucadendra was first formally described in 1762 by Carl Linnaeus in Species Plantarum as Myrtus leucadendra. Linnaeus used a description of the species written by Georg Eberhard Rumphius in 1741, before the modern system of classification was devised by Linnaeus. Rumphius had described a plant growing in. Linnaeus realised that this species had little in common with other species in the genus Myrtus and described the genus Melaleuca to accommodate this species.
Thus, Melaleuca leucadendra became the first melaleuca to be formally described. The description was published in 1767 in Mantissa plantarum, it follows that although nearly all melaeucas are found only in Australia, the first type specimen was from Indonesia. The specific epithet is derived from the Ancient Greek words λευκός meaning “white” and δένδρον meaning “tree” referring to the white bark of this plant. Melaleuca leucadendra is superficially similar to other paperbark trees Melaleuca cajuputi, Melaleuca quinquenervia, Melaleuca linariifolia and Melaleuca viridiflora and all are sometimes referred to as cajuput or cajeput. Cajuput is an English word for the oil obtained from the foliage of Melaleuca cajuputi and the word is a corruption of kayu putih, the Indonesian name for the tree; the Malay name for the paperbark tree is gelam and may have given its name to the Kampong Glam district in Singapore. The name Melaleuca leucadendron is sometimes given, but it is an orthographical variant meaning that it is a spelling mistake.
This melaleuca is distributed in northern parts of Western Australia, the Northern Territory and in Queensland as far south as Shoalwater Bay. It occurs in New Guinea and Indonesia, it streams on a range of soils. Aboriginal people used strips of bark from this tree and tied them to a frame of Dodonaea branches to build huts that were waterproof; the bark was used to wrap food before cooking in an underground oven called a kap mari. It was used to wrap the bodies of their dead; the bark from trunks of large trees was used to make bark canoes. The crushed leaves were used to the flowers for making a sweet drink; this species of melaleuca is grown in parks and as a street tree in tropical and sub-tropical areas like Brisbane and as far south as Sydney. It will tolerate poor, waterlogged soils, it has been used as a street tree in Hong Kong. A range of essential oils can be distilled depending on where the trees occur. Two of the most common chemotypes are based on E-methyl isoeugenol; the timber from M. leucadendra can be used for general construction.
In Vietnam, it is used for poles and woodchips
Liniment, or embrocation, is a medicated topical preparation for application to the skin. Sometimes called balms or heat rubs, liniments are of a similar or greater viscosity than lotions and are rubbed in to create friction, unlike lotions, ointments or creams, but patches and sprays are available. Liniments are sold to relieve pain and stiffness, such as from sore muscular aches and strains, or arthritis; these are formulated from alcohol, acetone, or similar evaporating solvents and contain counterirritant aromatic chemical compounds such as methyl salicilate, benzoin resin, menthol, or capsaicin. They produce a feeling of warmth within the muscle of the area they are applied to acting as rubefacients via a counterirritant effect; the methyl salicylate, the active analgesic ingredient in some heat-rub products can be toxic if they are used in excess. Heating pads are not recommended for use with heat rubs, as the added warmth may cause overabsorption of the active ingredients. A. B. C. Liniment is a old rubbing mixture or liniment.
It was used for a long period of time as a way of relieving pain caused by lumbago, neuralgia, stiffness after exercise and other conditions. It was made from aconite and chloroform, leading to its name. However, there have been numerous examples of poisoning from the mixture, resulting in at least one death. Bengay, spelled Ben-Gay before 1995, is a liniment used to temporarily relieve muscle and joint pain associated with arthritis, simple backaches and strains, it was developed in France by Dr. Jules Bengué, brought to America in 1898; the name Bengué was anglicized to Bengay. It was produced by Pfizer Consumer Healthcare, acquired by Johnson & Johnson. Flex-power is a liniment. IcyHot is a line of liniments produced and marketed by Chattem, now a subsidiary of Sanofi Mentholatum Ointment was introduced in December 1894 by a US company founded by Albert Alexander Hyde. In 1975 a Japanese pharmaceutical company, Rohto Pharmaceutical Co. bought the rights to market the product and in 1988 it bought the entire Mentholatum company.
The ointment has a brand, "Deep Heat". Minard's Liniment: Dr. Levi Minard from Hants County, Nova Scotia, branded as "The King of Pain", created this preparation which he developed in the 1860s from camphor, ammonia water, medical turpentine, its use was popular in Eastern Canada. Opodeldoc is a formulation invented by the Renaissance physician Paracelsus RUB A535 is a liniment introduced in 1919 and manufactured by Church & Dwight in Canada, it is not well known outside of Canada, is not sold in the United States. Tiger Balm was developed during the 1870s in Rangoon, Burma, by herbalist Aw Chu Kin, son of a Hakka herbalist in China, Aw Leng Fan and brought to market by his sons. Made of Menthol, Oil of Wintergreen. Liniments are used on horses following exercise, applied either by rubbing on full-strength on the legs, they are used in hot weather to help cool down a horse after working, the alcohol cooling through rapid evaporation, counterirritant oils dilating capillaries in the skin, increasing the amount of blood releasing heat from the body.
Many horse liniment formulas in diluted form have been used on humans, though products for horses which contain DMSO are not suitable for human use, as DMSO carries the topical product into the bloodstream. Horse liniment ingredients such as menthol, chloroxylenol, or iodine are used in different formulas in products used by humans. Absorbine, a horse liniment product manufactured by W. F. Young, Inc. was marketed as Absorbine Jr.. The company acquired other liniment brands including Bigeloil and RefreshMint; the equine version of Absorbine is sometimes used by humans, though its benefits in humans may be because the smell of menthol releases serotonin, or due to a placebo effect. Earl Sloan was a US entrepreneur who made his initial fortune selling his father's horse liniment formula beginning in the period following the Civil War. Sloan's liniment, with capsicum as a key ingredient, was marketed for human use, he sold his company to the predecessor of Warner–Lambert, purchased in 2000 by Pfizer
Sulawesi known as Celebes, is an island in Indonesia. One of the four Greater Sunda Islands, the world's eleventh-largest island, it is situated east of Borneo, west of the Maluku Islands, south of Mindanao and the Sulu Archipelago. Within Indonesia, only Sumatra and Papua are larger in territory, only Java and Sumatra have larger populations; the landmass of Sulawesi includes four peninsulas: the northern Minahasa Peninsula. Three gulfs separate these peninsulas: the Gulf of Tomini between the northern Minahasa and East peninsulas; the Strait of Makassar runs along the western side of the island and separates the island from Borneo. The name Sulawesi comes from the words sula and besi and may refer to the historical export of iron from the rich Lake Matano iron deposits; the name came into common use in English following Indonesian independence. The name Celebes was given to the island by Portuguese explorers. While its direct translation is unclear, it may be considered a Portuguese rendering of the native name "Sulawesi".
Sulawesi is the world's eleventh-largest island, covering an area of 174,600 km2. The central part of the island is ruggedly mountainous, such that the island's peninsulas have traditionally been remote from each other, with better connections by sea than by road; the three bays that divide Sulawesi's peninsulas are, from north to south, the Tomini, the Tolo and the Boni. These separate the Minahassa or Northern Peninsula, the East Peninsula, the Southeast Peninsula and the South Peninsula; the Strait of Makassar runs along the western side of the island. The island is surrounded by Borneo to the west, by the Philippines to the north, by Maluku to the east, by Flores and Timor to the south; the Selayar Islands make up a peninsula stretching southwards from Southwest Sulawesi into the Flores Sea are administratively part of Sulawesi. The Sangihe Islands and Talaud Islands stretch northward from the northeastern tip of Sulawesi, while Buton Island and its neighbours lie off its southeast peninsula, the Togian Islands are in the Gulf of Tomini, Peleng Island and Banggai Islands form a cluster between Sulawesi and Maluku.
All the above-mentioned islands, many smaller ones are administratively part of Sulawesi's six provinces. The island slopes up from the shores of the deep seas surrounding the island to a high non-volcanic, mountainous interior. Active volcanoes are found in the northern Minahassa Peninsula, stretching north to the Sangihe Islands; the northern peninsula contains several active volcanoes such as Mount Lokon, Mount Awu and Karangetang. According to plate reconstructions, the island is believed to have been formed by the collision of terranes from the Asian Plate and from the Australian Plate, with island arcs in the Pacific; because of its several tectonic origins, various faults scar the land and as a result the island is prone to earthquakes. Sulawesi, in contrast to most of the other islands in the biogeographical region of Wallacea, is not oceanic, but a composite island at the centre of the Asia-Australia collision zone. Parts of the island were attached to either the Asian or Australian continental margin and became separated from these areas by vicariant processes.
In the west, the opening of the Makassar Strait separated West Sulawesi from Sundaland in the Eocene c. 45 Mya. In the east, the traditional view of collisions of multiple micro-continental fragments sliced from New Guinea with an active volcanic margin in West Sulawesi at different times since the Early Miocene c. 20 Mya has been replaced by the hypothesis that extensional fragmentation has followed a single Miocene collision of West Sulawesi with the Sula Spur, the western end of an ancient folded belt of Variscan origin in the Late Paleozoic. Before October 2014, the settlement of South Sulawesi by modern humans had been dated to c. 30,000 BC on the basis of radiocarbon dates obtained from rock shelters in Maros. No earlier evidence of human occupation had at that point been found, but the island certainly formed part of the land bridge used for the settlement of Australia and New Guinea by at least 40,000 BCE. There is no evidence of Homo erectus having reached Sulawesi. Following Peter Bellwood's model of a southward migration of Austronesian-speaking farmers, radiocarbon dates from caves in Maros suggest a date in the mid-second millennium BC for the arrival of a group from east Borneo speaking a Proto-South Sulawesi language.
Initial settlement was around the mouth of the Sa'dan river, on the northwest coast of the peninsula, although the south coast has been suggested. Subsequent migrations across the mountainous landscape resulted in the geographical isolation of PSS speakers and the evolution of their languages into the eight families of the South Sulawesi language group. If each group can be said to have a homeland, that of the Bugis – today the most numerous group – was around lakes Témpé and Sidénréng in the Walennaé depression. Here for some 2,000 years lived the linguistic group. Despite the fact that today they are link
Velvet (fish disease)
Velvet disease is a fish disease caused by dinoflagellate parasites of the genus Piscinoodinium Amyloodinium in marine fish, Oodinium in freshwater fish. The disease gives infected organisms a brownish-gold color; the disease occurs most in tropical fish, to a lesser extent, marine aquaria. The single-celled parasite's life cycle can be divided into three major phases. First, as a tomont, the parasite divides into as many as 256 tomites. Second, these juvenile, motile tomites swim about in search of a fish host, meanwhile using photosynthesis to grow, to fuel their search; the adolescent tomite finds and enters the slime coat of a host fish and consuming the host's cells, needing only three days to reach full maturity before detaching to become a tomont once more. Velvet is spread by contaminated tanks and tools. There are rare reports of frozen live foods containing dormant forms of the species. However, the parasite is endemic to a fish, only causes a noticeable "outbreak" after the fish's immune system is compromised for some other reason.
The disease is contagious and can prove fatal to fish. Infected fish are known to "flash", or sporadically dart from one end of an aquarium to another, scratching against objects in order to relieve their discomfort, they will "clamp" their fins close to their body, exhibit lethargy. If untreated, a'dusting' of particles will be seen all over the infected fish, ranging in color from brown to gold to green. In the most advanced stages, fish will have difficulty respiring, will refuse food, will die of hypoxia due to necrosis of their gill tissue. Sodium chloride is believed to mitigate the reproduction of velvet, however this treatment is not itself sufficient for the complete eradication of an outbreak. Additional, common medications added directly to the fish's environment include copper sulfate, methylene blue, malachite green and acriflavin, all of which can be found in common fish medications designed to combat this disease. Additionally, because velvet parasites derive a portion of their energy from photosynthesis, leaving a tank in total darkness for seven days provides a helpful supplement to chemical curatives.
Some enthusiasts recommend raising the water temperature of an infected fish's environment, in order to quicken the life cycle of velvet parasites. Pfiesteria piscicida
Phosphorus pentoxide is a chemical compound with molecular formula P4O10. This white crystalline solid is the anhydride of phosphoric acid, it is dehydrating agent. Phosphorus polymorphs; the most familiar one, a metastable form, shown in the figure, comprises molecules of P4O10. Weak van der Waals forces hold these molecules together in a hexagonal lattice; the structure of the P4O10 cage is reminiscent of adamantane with Td symmetry point group. It is related to the corresponding anhydride of phosphorous acid, P4O6; the latter lacks terminal oxo groups. Its density is 2.30 g/cm3. It boils at 423 °C under atmospheric pressure; this form can be made by condensing the vapor of phosphorus pentoxide the result is an hygroscopic solid. The other polymorphs are polymeric, but in each case the phosphorus atoms are bound by a tetrahedron of oxygen atoms, one of which forms a terminal P=O bond involving the donation of the terminal oxygen p-orbital electrons to the antibonding phosphorus-oxygen single bonds.
The macromolecular form can be made by heating the compound in a sealed tube for several hours, maintaining the melt at a high temperature before cooling the melt to the solid. The metastable orthorhombic, "O"-form, adopts a layered structure consisting of interconnected P6O6 rings, not unlike the structure adopted by certain polysilicates; the stable form is a higher density phase orthorhombic, the so-called O' form. It consists of a 3-dimensional framework, density 3.5 g/cm3. The remaining polymorph is a glass or amorphous form. P4O10 is prepared by burning tetraphosphorus with sufficient supply of oxygen: P4 + 5 O2 → P4O10For most of the 20th century, phosphorus pentoxide was used to provide a supply of concentrated pure phosphoric acid. In the thermal process, the phosphorus pentoxide obtained by burning white phosphorus was dissolved in dilute phosphoric acid to produce concentrated acid. Improvements in filter technology is leading to the "wet phosphoric acid process" taking over from the thermal process, obviating the need to produce white phosphorus as a starting material.
The dehydration of phosphoric acid to give phosphorus pentoxide is not possible as on heating metaphosphoric acid will boil without losing all its water. Phosphorus pentoxide is a potent dehydrating agent as indicated by the exothermic nature of its hydrolysis: P4O10 + 6 H2O → 4 H3PO4 However, its utility for drying is limited somewhat by its tendency to form a protective viscous coating that inhibits further dehydration by unspent material. A granular form of P4O10 is used in desiccators. Consistent with its strong desiccating power, P4O10 is used in organic synthesis for dehydration; the most important application is for the conversion of primary amides into nitriles: P4O10 + RCNH2 → P4O92 + RCNThe indicated coproduct P4O92 is an idealized formula for undefined products resulting from the hydration of P4O10. Alternatively, when combined with a carboxylic acid, the result is the corresponding anhydride: P4O10 + RCO2H → P4O92 + 2OThe "Onodera reagent", a solution of P4O10 in DMSO, is employed for the oxidation of alcohols.
This reaction is reminiscent of the Swern oxidation. The desiccating power of P4O10 is strong enough to convert many mineral acids to their anhydrides. Examples: HNO3 is converted to N2O5. Between the commercially important P4O6 and P4O10, phosphorus oxides are known with intermediate structures. Phosphorus pentoxide. Just like sulfur trioxide, it reacts vigorously with water and water-containing substances like wood or cotton, liberates much heat and may cause fire due to the exothermic nature of such reactions, it is corrosive to metal and is irritating – it may cause severe burns to the eye, mucous membrane, respiratory tract at concentrations as low as 1 mg/m3. In Anthony Burgess' The Wanting Seed, phosphorus pentoxide is a prized compound. In Detective Comics #825, Batman notices that phosphorus pentoxide was at the scene of a fire, indicating that the villain Dr. Phosphorus was involved. In Aldous Huxley's Point Counter Point, to his assistant Illidge, Lord Edward bemoans societal loss of phosphorous pentoxide.
In Aldous Huxley's Brave New World, Henry Foster tells Lenina about the recovery of phosphorus pentoxide. In The Tunnel, a victim was consumed by a fire started with phosphorus pentoxide. Eaton's reagent OSHA Spec sheet Definition Website of the Technische Universität Darmstadt and the CEEP about Phosphorus Recovery
Melaleuca is a genus of nearly 300 species of plants in the myrtle family, Myrtaceae known as paperbarks, honey-myrtles or tea-trees. They range in size from small shrubs that grow to more than 1 m high, to trees up to 35 m, their flowers occur in groups, forming a “head” or “spike” resembling a brush used for cleaning bottles, containing up to 80 individual flowers. They are superficially like Banksia species, which have their flowers in a spike, but the structures of individual flowers in the two genera are different. Second only to members of the family Proteaceae, melaleucas are an important food source for nectarivorous insects and mammals. Many are popular garden plants, either as dense screens. Most melaleucas are endemic to Australia, with a few occurring in Malesia. Seven are endemic to New Caledonia, one is found only on Lord Howe Island. Melaleucas are found in a wide variety of habitats. Many are adapted for life in swamps and boggy places, while others thrive in the poorest of sandy soils or on the edge of saltpans.
Some have a wide distribution and are common, whilst others are rare and endangered. Land clearing, exotic myrtle rust, draining and clearing of swamps threaten many species. Melaleucas range in size from small shrubs such as M. aspalathoides and M. concinna which grow to more than 1 m high, to trees like M. cajuputi and M. quinquenervia, which can reach 35 m. Many, like M. lineariifolia, are known as paperbarks and have bark that can be peeled in thin sheets, whilst about 20% of the genus, including M. bracteata, have hard, rough bark and another 20% have fibrous bark. Every species in the genus is an evergreen, the leaves vary in size from minute and scale-like to 270 mm long. Most have distinct oil glands dotted in the leaves, making the leaves aromatic when crushed. Melaleuca flowers are arranged in spikes or heads. Within the head or spike, the flowers are in groups of two or three, each flower or group having a papery bract at its base. Five sepals occur, although these are sometimes fused into a ring of tissue and five petals which are small, not showy, fall off as the flower opens or soon after.
The stamens vary in colour, from white to cream or yellow, red, or mauve with their yellow tips contrasting with their "stalks". The fruit are woody, cup-shaped, barrel-shaped, or spherical capsules arranged in clusters along the stems; the seeds are sometimes retained in the fruit for many years, only opening when the plant, or part of it, dies or is heated in a bushfire. In tropical areas, seeds are released annually in the wet season; the first known description of a Melaleuca species was written by Rumphius in 1741, in Herbarium amboinense before the present system of naming plants was written. The plant he called; the name Melaleuca was first used by Linnaeus in 1767. Many species known as Metrosideros were placed in Melaleuca. In Australia, Melaleuca is the third most diverse plant genus with up to 300 species; the genus Callistemon was raised by Robert Brown, who noted its similarity to Melaleuca, distinguishing it only on the basis of whether the stamens are free of each other, or joined in bundles.
Botanists in the past, including Ferdinand von Mueller and Lyndley Craven have proposed uniting the two genera but the matter is not decided. Evidence from DNA studies suggests that either Callistemon and some other genera be incorporated into Melaleuca or that at least 10 new genera be created from the present genus. In 2014, Lyndley Craven and others proposed, on the basis of DNA evidence, that species in the genera Beaufortia, Conothamnus, Lamarchea, Petraeomyrtus and Regelia be transferred to Melaleuca; the World Checklist of Selected Plant Families maintained by the Royal Botanic Gardens, Kew lists Calothamnus and the other genera as synonyms of the accepted genus Melaleuca. The move has not been adopted by all Australian herbaria with some taxonomists, including Alex George opposing the move; the name Melaleuca is derived from the Ancient Greek μέλας meaning “dark" or "black” and λευκός meaning “white” because one of the first specimens described had fire-blackened white bark. The common name "tea-tree" has been applied to species in the genera Leptospermum, Melaleuca and Baeckea because the sailors on the Endeavour used the leaves of a shrub from one of these groups as a replacement for tea Camellia sinensis during Captain James Cook's 1770 voyage to Australia.
Most melaleucas occur only on the Australian mainland. Eight occur in Tasmania. One is endemic to Lord Howe Island and seven are endemic to Grande Terre, the main island of New Caledonia. A few tropical species occur in Papua New Guinea, the distribution of one subspecies, Melaleuca cajuputi subsp. Cumingiana extends as far north as Myanmar and Vietnam; the southwest of Western Australia has the greatest density of species, in the tropical north of the continent, species such as M. argentea and M. leucadendra are the dominant species over large areas. Melaleucas grow in a range of soil types and many tolerate occasional or permanent waterlogging; some species the South Australian swamp paperbark, M. halmaturorum, thrive in saline soils where few other species survive. Many