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4,414 | 720 | 4 | 999 | 248 | 25 | 8 | 249 | 460 mm) armament of the Japanese Yamato class of World War II. One consideration which became more acute was that even from the original Armstrong models, following the Crimean War, range and hitting power far exceeded simple accuracy, especially at sea where the slightest roll or pitch of the vessel as'floating weapon... |
3,950 | 636 | 4 | 1,000 | 247 | 26 | 8 | 247 | rapidly after combustion; this meant cannons had relatively short barrels, to prevent the barrel itself slowing the shell. The sharpness of the black powder explosion also meant that guns were subjected to extreme stress. One important step was to press the powder into pellets, allowing a slower, more controlled explos... |
4,078 | 656 | 4 | 998 | 248 | 27 | 8 | 248 | , making use of improved propellants to gain greater muzzle velocity.
The nature of the projectiles also changed during the ironclad period. Initially, the best armor-piercing projectile was a solid cast-iron shot. Later, shot of chilled iron, a harder iron alloy, gave better armor-piercing qualities. Eventually the ar... |
4,102 | 648 | 4 | 997 | 247 | 28 | 8 | 247 | Italy, Austria, Russia and the United States. The advantages of mounting guns on both broadsides was that the ship could engage more than one adversary at a time, and the rigging did not impede the field of fire.
Broadside armament also had disadvantages, which became more serious as ironclad technology developed. Heav... |
3,630 | 588 | 4 | 999 | 248 | 29 | 8 | 249 | ored, this arrangement was called a turret and when partially armored or unarmored, a barbette.
The centre-battery was the simpler and, during the 1860s and 1870s, the more popular method. Concentrating guns amidships meant the ship could be shorter and handier than a broadside type. The first full-scale centre-battery... |
4,086 | 664 | 4 | 998 | 248 | 30 | 8 | 248 | central spindle, and Coles's turned on a ring of bearings. Turrets offered the maximum arc of fire from the guns, but there were significant problems with their use in the 1860s. The fire arc of a turret would be considerably limited by masts and rigging, so they were unsuited to use on the earlier ocean-going ironclad... |
3,982 | 656 | 4 | 998 | 248 | 31 | 8 | 248 | ', was designed by Captain Cowper Phipps Coles: HMS Captain, a dangerously low freeboard turret ship which nevertheless carried a full rig of sail, and which subsequently capsized not long after her launch in 1870. Her half-sister HMS Monarch was restricted to firing from her turrets only on the port and starboard beam... |
3,854 | 616 | 4 | 998 | 248 | 32 | 8 | 248 | bette became widely adopted in the 1880s, and with the addition of an armored' gun-house ', transformed into the turrets of the pre-Dreadnought battleships.
=== Torpedoes ===
The ironclad age saw the development of explosive torpedoes as naval weapons, which helped complicate the design and tactics of ironclad fleets... |
3,770 | 640 | 4 | 1,000 | 247 | 33 | 8 | 247 | involved an explosive on a line or outrigger; either to deter a ship from ramming or to make a torpedo attack by a boat less suicidal.
A more practical and influential weapon was the self-propelled or Whitehead torpedo. Invented in 1868 and deployed in the 1870s, the Whitehead torpedo formed part of the armament of iro... |
3,678 | 588 | 4 | 998 | 248 | 34 | 8 | 248 | ought iron armor backed by thick wooden planking. Ironclads were still being built with wooden hulls into the 1870s.
=== Hulls: iron, wood and steel ===
Using iron construction for warships offered advantages for the engineering of the hull. However, unarmored iron had many military disadvantages, and offered technic... |
4,294 | 704 | 4 | 998 | 248 | 35 | 8 | 248 | was only adopted as a building material for battleships when protected by armor. However, iron gave the naval architect many advantages. Iron allowed larger ships and more flexible design, for instance the use of watertight bulkheads on the lower decks. Warrior, built of iron, was longer and faster than the wooden-hull... |
4,210 | 700 | 4 | 998 | 248 | 36 | 8 | 248 | life, slowing the ships down — manageable for a European battlefleet close to dry docks, but a difficulty for long-range ships. The only solution was to sheath the iron hull first in wood and then in copper, a laborious and expensive process which made wooden construction remain attractive. Iron and wood were to some e... |
3,670 | 616 | 4 | 1,000 | 248 | 37 | 8 | 250 | ctions for large-scale use on ships. French manufacturers used the Siemens-Martin process to produce adequate steel, but British technology lagged behind. The first all-steel warships built by the Royal Navy were the dispatch vessels Iris and Mercury, laid down in 1875 and 1876.
=== Armor and protection schemes ===
I... |
3,530 | 600 | 4 | 998 | 248 | 38 | 8 | 248 | was found to fuse steel onto wrought iron plates, giving a form of compound armor. This compound armor was used by the British in ships built from the late 1870s, first for turret armor (starting with HMS Inflexible) and then for all armor (starting with HMS Colossus of 1882). The French and German navies adopted the i... |
3,486 | 612 | 4 | 998 | 248 | 39 | 8 | 248 | . In 1890, the U.S. Navy tested steel armor hardened by the Harvey process and found it superior to compound armor. For several years'Harvey steel' was the state of the art, produced in the U.S., France, Germany, Britain, Austria and Italy. In 1894, the German firm Krupp developed gas cementing, which further hardened ... |
3,910 | 608 | 4 | 998 | 248 | 40 | 8 | 248 | and to 7.75 in (197 mm) of Harvey armor or 5.75 in (146 mm) of Krupp armor.
Ironclad construction also prefigured the later debate in battleship design between tapering and 'all-or-nothing' armour design. Warrior was only semi-armoured, and could have been disabled by hits on the bow and stern. As the thickness of armo... |
4,222 | 708 | 4 | 998 | 248 | 41 | 8 | 248 | efficient; the wooden steam fleet of the Royal Navy could only carry "5 to 9 days coal", and the situation was similar with the early ironclads. Warrior also illustrates two design features which aided hybrid propulsion; she had retractable screws to reduce drag while under sail (though in practice the steam engine was... |
4,130 | 668 | 4 | 999 | 248 | 42 | 8 | 249 | ads of the 1870s retained masts, and only the Italian navy, which during that decade was focused on short-range operations in the Adriatic, built consistently mastless ironclads.
During the 1860s, steam engines improved with the adoption of double-expansion steam engines, which used 30 – 40 % less coal than earlier mod... |
3,586 | 548 | 4 | 998 | 248 | 43 | 8 | 248 | as it was in theory.
During the 1870s the distinction grew between' first-class ironclads'or' battleships'on the one hand, and' cruising ironclads'designed for long-range work on the other. The demands on first-class ironclads for very heavy armor and armament meant increasing displacement, which reduced speed under sa... |
3,594 | 596 | 4 | 998 | 248 | 44 | 8 | 248 | of 1870. The Russian ship General-Admiral, laid down in 1870 and completed in 1875, was a model of a fast, long-range ironclad which was likely to be able to outrun and outfight ships like Swiftsure. Even the later HMS Shannon, often described as the first British armored cruiser, would have been too slow to outrun Gen... |
4,274 | 644 | 4 | 998 | 248 | 45 | 8 | 248 | -expansion steam engine, a further refinement which was first adopted in HMS Sans Pareil, laid down in 1885 and commissioned in 1891. Many ships also used a forced draught to get additional power from their engines, and this system was widely used until the introduction of the steam turbine in the mid-1900s (decade).
... |
4,106 | 672 | 4 | 1,000 | 247 | 46 | 8 | 247 | strictly naval foreign intervention, from Hampton Roads in the American Civil War to the hardening combined defences of naval arsenals such as Kronstadt and Cherbourg.
There were many types of ironclads:
Seagoing ships intended to "stand in the line of battle"; the precursors of the battleship.
Coastal service and rive... |
4,266 | 620 | 4 | 998 | 248 | 47 | 8 | 248 | this end, the Royal Navy developed a series of 'coast-defence battleships', starting with the Devastation class. These 'breastwork monitors' were markedly different from the other high-seas ironclads of the period and were an important precursor of the modern battleship. As long-range monitors they could reach Bermuda ... |
3,798 | 568 | 4 | 997 | 247 | 48 | 8 | 247 | Admiralty frequently acknowledged but never countered throughout the period. The British never laid down enough Devastation-class'battleships' to instantly overwhelm Cherbourg, Kronstadt or even New York City with gunfire. Although throughout the 1860s and 1870s the Royal Navy was still in many respects superior to its... |
4,370 | 688 | 4 | 1,000 | 247 | 49 | 8 | 247 | fleet opened fire on the fortifications around the port of Alexandria. A mixture of centre-battery and turret ships bombarded Egyptian positions for most of a day, forcing the Egyptians to retreat; return fire from Egyptian guns was heavy at first, but inflicted little damage, killing only five British sailors. Few Egy... |
3,882 | 620 | 4 | 998 | 248 | 50 | 8 | 248 | clads ceased for a while in France as the Jeune Ecole school of naval thought took prominence, suggesting that torpedo boats and unarmored cruisers would be the future of warships. Like the British, the French navy saw little action with its ironclads; the French blockade of Germany in the Franco-Prussian War was ineff... |
3,626 | 604 | 4 | 999 | 249 | 51 | 8 | 249 | 1880s and 1890s with modern armored cruisers and battleships, but the ships were manned by inexperienced crews and politically appointed leadership, which enhanced their defeat in the Battle of Tsushima on 27 May 1905.
The U.S. Navy ended the Civil War with about fifty monitor-type coastal ironclads; by the 1870s most ... |
3,694 | 608 | 4 | 998 | 248 | 52 | 8 | 248 | a new era of naval warfare.
Ironclads were widely used in South America. Both sides used ironclads in the Chincha Islands War between Spain and the combined forces of Peru and Chile in the early 1860s. The powerful Spanish Numancia participated in the Battle of Callao but was unable to inflict significant damage to the... |
3,870 | 600 | 4 | 999 | 248 | 53 | 8 | 249 | 1879, both Peru and Chile had ironclad warships, including some of those used a few years previously against Spain. While the Independencia ran aground early on, the Peruvian ironclad 'Huáscar made a great impact against Chilean shipping, delaying Chilean ground invasion by six months. She was eventually caught by two ... |
3,950 | 648 | 4 | 998 | 248 | 54 | 8 | 248 | Beiyang fleet which was superior on paper at least at the Battle of the Yalu River. Thanks to superior short-range firepower, the Japanese fleet came off better, sinking or severely damaging eight ships and receiving serious damage to only four. The naval war was concluded the next year at the Battle of Weihaiwei, wher... |
3,362 | 576 | 4 | 997 | 247 | 55 | 8 | 247 | battleship design, the dreadnought, is never referred to as an' ironclad '.
Most of the ironclads of the 1870s and 1880s served into the 1900s (decade). For instance, a handful of US navy monitors laid down in the 1870s saw active service in World War I. Pre-Dreadnought battleships and cruisers of the 1890s saw widespr... |
3,590 | 576 | 4 | 999 | 248 | 56 | 8 | 249 | ads have been preserved or reconstructed as museum ships.
Parts of USS Monitor have been recovered and are being conserved and displayed at the Mariners' Museum in Newport News, Virginia
HMS Warrior is today a fully restored museum ship in Portsmouth, England
Huáscar is berthed at the port of Talcahuano, Chile, on disp... |
1,534 | 256 | 4 | 396 | 96 | 57 | 8 | 96 | Carolina, and, in another part of town on the Neuse River, the recreated ship, named CSS Neuse II, is nearly built and can be visited.
The hull of the casemate ironclad CSS Jackson can be seen in the National Civil War Naval Museum at Port Columbus, Georgia.
The new United States Navy Zumwalt-class guided missile destr... |
4,086 | 680 | 4 | 999 | 249 | 0 | 9 | 249 | = Little Gidding (poem) =
Little Gidding is the fourth and final poem of T. S. Eliot's Four Quartets, a series of poems that discuss time, perspective, humanity, and salvation. It was first published in September 1942 after being delayed for over a year because of the air-raids on Great Britain during World War II an... |
4,122 | 700 | 4 | 998 | 248 | 1 | 9 | 248 | is necessary for salvation.
== Background ==
Following the completion of the third Four Quartets poem, The Dry Salvages, Eliot's health declined and he stayed in Shamley Green, Surrey while he recovered. During this time, Eliot started writing Little Gidding. The first draft was completed in July 1941 but he was diss... |
4,230 | 692 | 4 | 997 | 247 | 2 | 9 | 247 | Eliot's views expressed in this series of poems.
Little Gidding was the home of an Anglican community established in 1626 by Nicholas Ferrar. The Ferrar household lived a Christian life according to High Church principles and the Book of Common Prayer. The religious community was dispersed during the English Civil War ... |
4,214 | 700 | 4 | 998 | 248 | 3 | 9 | 248 | and how fire is the primary element of the four. Following this is a discussion on death and destruction, things unaccomplished, and regret for past events.
While using Dante's terza rima style, the poem continues by describing the Battle of Britain. The image of warfare merges with the depiction of Pentecost, and the ... |
4,206 | 732 | 4 | 998 | 248 | 4 | 9 | 248 | allow an individual to die into life and be reborn, and that salvation should be the goal of humankind.
== Themes ==
In terms of renewal, Eliot believed that suffering was needed for all of society before new life could begin. The original Little Gidding community was built for living on monastic lines, but the commu... |
4,342 | 724 | 4 | 998 | 248 | 5 | 9 | 248 | The Family Reunion.
Like the other poems making up the Four Quartets, Little Gidding deals with the past, present, and future, and humanity's place within them as each generation is seemingly united. In the second section, there is a ghost who is the compilation of various poets, including Dante, Swift, Yeats, and othe... |
4,178 | 756 | 4 | 998 | 248 | 6 | 9 | 248 | before being revised as an ambiguous "you". "Ser Brunetto" was Dante's way of addressing Brunetto Latini, a former mentor whom he meets in Hell to which he has been condemned for sodomy. Eliot, in a letter to John Hayward dated 27 August 1942, explained why he changed the wording:
I think you will recognise that it was... |
3,942 | 632 | 4 | 998 | 248 | 7 | 9 | 248 | flames is connected to the depiction of Guido Guinizelli, a poet that influenced Dante, seeking such a state in Purgatorio XXVI. However, the depiction of swimming was transformed into an image of dancing, an act that appears throughout Yeats's poetry, within purgatorial flames. The critic Dominic Manganiello suggests ... |
2,878 | 520 | 4 | 752 | 185 | 8 | 9 | 185 | greatest achievement in the Four Quartets." E. M. Forster did not like Eliot's emphasis on pain and responded to the poem: "Of course there's pain on and off through each individual's life ... You can 't shirk it and so on. But why should it be endorsed by the schoolmaster and sanctified by the priest until the fire an... |
3,694 | 652 | 4 | 999 | 249 | 0 | 10 | 249 | = The Portage to San Cristobal of A.H. =
The Portage to San Cristobal of A.H. is a 1981 literary and philosophical novella by George Steiner, in which Jewish Nazi hunters find a fictional Adolf Hitler (A.H.) alive in the Amazon jungle thirty years after the end of World War II. The book generated considerable controv... |
4,006 | 644 | 4 | 998 | 248 | 1 | 10 | 248 | and starred John Cullum as Hitler.
== Plot summary ==
From his base in Tel Aviv, Holocaust survivor Emmanuel Lieber directs a group of Jewish Nazi hunters in search of Adolf Hitler. Lieber believes that the former Führer is still alive, and following rumours and hearsay, he tracks Hitler's movements through South Ame... |
4,310 | 760 | 4 | 998 | 248 | 2 | 10 | 248 | is identified as the nearest airfield to the last known location of the search party, and aircraft begin arriving at the hitherto unknown town. But when the search party loses radio contact with Lieber, they must make a decision: do they sit out the storms and deliver their captive to Lieber later, or do they try Hitle... |
3,790 | 640 | 4 | 997 | 247 | 3 | 10 | 247 | their need to separate themselves from the "unclean". "My racism is a parody of yours, a hungry imitation."
Hitler justifies the Final Solution by maintaining that the Jews'God, purer than any other, enslaves its subjects, continually demanding more than they can give and "blackmailing" them with ideals that cannot be ... |
3,798 | 640 | 4 | 998 | 248 | 4 | 10 | 248 | is the first to react and jumps up shouting "Proven", only to be drowned out by the appearance of a helicopter over the clearing.
== Main characters ==
Emmanuel Lieber – Jewish Holocaust survivor and director of the search party to find Hitler; after crawling out of a death pit in Bialka he never took the time to men... |
3,674 | 612 | 4 | 999 | 248 | 5 | 10 | 249 | ium and spending three years recuperating in Paris where the care-free living consumed him with guilt.
Elie Barach – Orthodox Jew and "prosecution attorney" at the trial; he is the moral compass of the group, but his convictions are disturbed by Gideon Benasseraf's fever-induced assertions that Hitler is Jewish and end... |
3,930 | 636 | 4 | 998 | 248 | 6 | 10 | 248 | search party because of his military training and his clear-headedness ("no metaphysical lusts, no cravings for retribution").
Teku – local Indian tracker and independent witness at the trial; previously the search party's guide who had abandoned them when they insisted on entering uncharted regions of the jungle, he c... |
3,806 | 668 | 4 | 998 | 248 | 7 | 10 | 248 | J. R. Bruckner that this book arose out of his lifelong work on language. "Central to everything I am and believe and have written is my astonishment ... that you can use human speech both to bless, to love, to build, to forgive and also to torture, to hate, to destroy and to annihilate."
Commenting on the controversy ... |
3,726 | 624 | 4 | 997 | 247 | 8 | 10 | 247 | Geneva, Switzerland, and the 120-page work originally appeared in the Spring 1979 issue of the United States literary magazine, The Kenyon Review. It also appeared in the Spring 1980 issue of Granta, the British literary magazine. Its first publication in book form, with minor revisions by Steiner, was in May 1981 by F... |
4,050 | 664 | 4 | 998 | 248 | 9 | 10 | 248 | where it played at the Hartford Stage Company in Hartford, Connecticut, directed by Mark Lamos and starring John Cullum as Hitler.
This book is the only work of fiction by Steiner to have been adapted for the stage.
== Reception ==
Reaction to The Portage to San Cristobal of A.H. was mixed. Anthony Burgess in The Obs... |
4,178 | 668 | 4 | 999 | 248 | 10 | 10 | 249 | ived and badly executed novel, a sideshow distraction from the serious business of thinking through the unspeakable horrors of the Nazi era." He described it as "wearisome" that is "suffocate [d]" by too much "fine writing" (belles-lettres). He also complained that the characters are lifeless, and while they each have ... |
4,018 | 644 | 4 | 998 | 248 | 11 | 10 | 248 | Kafka and Proust". But Leonard's biggest criticism of the book was Hitler's speech, which he called "obscene", and Steiner's decision to end the book at that point, which Leonard said "not only denies the power of art to arrange and transcend, but ... makes me sick to my stomach."
Writing in the American literary magaz... |
4,142 | 616 | 4 | 998 | 248 | 12 | 10 | 248 | he", or sinks to "a dwindling sob of elegiac lament", Steiner's Lieber "mediates between these two extremes, ... simultaneously records and mourns, coldly enumerates yet carries an immense affect". What did concern the reviewer, however, was the way Steiner used ideas from his earlier works, that he had put them "virtu... |
4,170 | 680 | 4 | 998 | 248 | 13 | 10 | 248 | ", forcing us to confront him "in a way hardly seen before in fiction".
The Portage to San Cristobal of A.H. was a finalist in the 1983 PEN / Faulkner Award for Fiction.
== Controversy ==
The book generated considerable controversy because of its apparent "admiration for Hitler". The controversy grew further when the... |
3,910 | 640 | 4 | 998 | 248 | 14 | 10 | 248 | a critic of Israel's treatment of the Palestinians, of anti-Semitism.
In contrast, a Time magazine article at the time felt that Steiner's intention for the Hitler speech was to use it to explore his previously stated belief "that Hitler wielded language as an almost supernatural force", drawing attention to Nazi hunte... |
1,018 | 192 | 4 | 290 | 71 | 15 | 10 | 71 | his Hitler (A. H.) is "a fictive figure", and that it is not he who has the last word, but Teku, the Indian tracker, who shouts "Proven". Teku is also the Hebrew word used to indicate that "there are issues here beyond our wisdom to answer or decide."
his Hitler (A. H.) is "a fictive figure", and that it is not he w... |
3,782 | 532 | 4 | 999 | 249 | 0 | 11 | 249 | = Temnospondyli =
Temnospondyli (from Greek τέμνειν ( temnein, "to cut") and σπόνδυλος (spondylos, "vertebra") ) is a diverse subclass of extinct small to giant tetrapods — often considered primitive amphibians — that flourished worldwide during the Carboniferous, Permian, and Triassic periods. A few species continue... |
3,874 | 556 | 4 | 998 | 248 | 1 | 11 | 248 | many had characteristics, such as scales, claws, and armour-like bony plates, that distinguish them from modern amphibians.
Temnospondyls have been known since the early 19th century, and were initially thought to be reptiles. They were described at various times as batrachians, stegocephalians, and labyrinthodonts, al... |
3,810 | 552 | 4 | 998 | 248 | 2 | 11 | 248 | lepospondyls, or even as descendants of both groups (with caecilians evolving from lepospondyls and frogs and salamanders evolving from temnospondyls). Recent studies place a family of temnospondyls called the amphibamids as the closest relatives of modern amphibians. Similarities in teeth, skulls, and hearing structur... |
3,730 | 600 | 4 | 998 | 248 | 3 | 11 | 248 | from their bodies while on land, and these dermal bones may have been an early solution to the problem). Many temnospondyls also have canal-like grooves in their skulls called sensory sulci. The sulci, which usually run around the nostrils and eye sockets, are part of a lateral line system used to detect vibrations in ... |
3,706 | 612 | 4 | 999 | 248 | 4 | 11 | 249 | ular horns in the backs of their skulls, rounded projections of bone separated from the rest of the skull by indentations called otic notches; in some temnospondyls, such as Zatrachys, they are pointed and very prominent. Among the most distinguishing features of temnospondyls are the interpterygoid vacuities, two larg... |
4,082 | 624 | 4 | 997 | 247 | 5 | 11 | 247 | impressions of the bodies of three temnospondyls. These impressions show, when alive, they had smooth skin, robust limbs with webbed feet, and a ridge of skin on their undersides. Trackways referable to small temnospondyls have also been found in Carboniferous and Permian rocks. The trackways, called batrachichni, are ... |
3,946 | 616 | 4 | 998 | 248 | 6 | 11 | 248 | make movement easier under water or to allow cutaneous respiration, the absorption of oxygen through the skin.
Several groups of temnospondyls have large bony plates on their backs. One temnospondyl, Peltobatrachus, has armour-like plating that covers both its back and underside. The temnospondyl Laidleria also has ext... |
3,690 | 532 | 4 | 997 | 247 | 7 | 11 | 247 | partly terrestrial also have long neural spines on top of their vertebrae that would have stabilized the spine. Bony scutes are also seen in plagiosaurs, but unlike Peltobatrachus, Laidleria, Eryops, and dissorophids, these animals are thought to have been fully aquatic. Plagiosaurs may have inherited their armor from ... |
3,698 | 520 | 4 | 998 | 248 | 8 | 11 | 248 | elements support a spine-like neural arch, and well-developed interlocking projections called zygapophyses strengthen the connections between vertebrae. The strong backbone and strong limbs of many ratchitomous temnospondyls allowed them to be partially, and in some cases fully, terrestrial. In stereospondylous vertebr... |
3,566 | 564 | 4 | 998 | 248 | 9 | 11 | 248 | tooth, and considered it a reptile. Mastodonsaurus means "breast tooth lizard" after the nipple-like shape of the tip of the tooth.
The naming of these first specimens was disputed, however. Leopold Fitzinger named the animal Batrachosaurus in 1837. In 1841, English palaeontologist Richard Owen referred to the genus as... |
3,506 | 524 | 4 | 999 | 248 | 10 | 11 | 249 | ized conical teeth, Phytosaurus was later found to be a crocodile-like reptile. Additional material, including skulls, firmly placed Labyrinthodon as an amphibian. Jaeger also named Salamandroides giganteus in 1828, basing it on partial occiput, or back portion of the skull. In 1833, he described a complete skull of S.... |
3,422 | 524 | 4 | 997 | 247 | 11 | 11 | 247 | William Buckland. Other specimens were found in the red sandstone of Warwickshire. As more fossils were uncovered in England, Owen depicted these labyrinthodonts as the "highest" form of batrachian and compared them to crocodiles, which he considered the highest form of reptiles. He also noted the large labyrinthodonts... |
3,346 | 508 | 4 | 999 | 248 | 12 | 11 | 249 | 858, and Dasyceps in 1859. Baphetes is now placed as an early tetrapod outside Temnospondyli, and Rhombopholis is now considered a prolacertiform reptile.
Later in the 19th century, temnospondyls were classified as various members of Stegocephalia, a name coined by American paleontologist Edward Drinker Cope in 1868. C... |
3,702 | 540 | 4 | 998 | 248 | 13 | 11 | 248 | the skull that were interpreted as space for mucous glands.
Several suborders of stegocephalians were recognized in the late 19th and early 20th centuries. Animals now regarded as temnospondyls were primarily labyrinthodonts, but some were classified in the Branchiosauria. Branchiosaurs were small-bodied and had simple... |
3,810 | 580 | 4 | 998 | 248 | 14 | 11 | 248 | urs would be recognized as larval forms of temnospondyls lacking many of the typical features that define the group, and is no longer recognized as a distinct group.
Other animals that would later be classified as temnospondyls were placed in a group called Ganocephala, characterized by plate-like skull bones, small li... |
3,558 | 476 | 4 | 999 | 248 | 15 | 11 | 249 | ope classified Microsauria as a subgroup of Labyrinthodontia, placing many small, amphibian-like animals within it. Among them were Dendrerpeton, once placed in Ganocephala. Dendrerpeton was later placed as a labyrinthodont with other temnospondyls, but confusion existed for many years over the classification of small ... |
3,254 | 420 | 4 | 998 | 248 | 16 | 11 | 248 | erimi. Members of Rhachitomi, such as Archegosaurus and Eryops, had rhachitomous vertebrae with enlarged intercentra that displaced the pleurocentra. Labyrinthodonti, such as Mastodonsaurus, Trematosaurus, and Micropholis, had lost their pleurocentra, and the intercentra made up the entire body of the vertebrae. Embole... |
3,638 | 520 | 4 | 998 | 248 | 17 | 11 | 248 | li had amphicoelous centra composed only of the intercentra. Cope objected to von Zittel's classification, considering the vertebrae of lepospondyls and stereospondyls indistinguishable because each had a simple spool shape. He continued to use Ganocephala and Labyrinthodonta (which he alternatively referred to as Rhac... |
3,738 | 504 | 4 | 998 | 248 | 18 | 11 | 248 | importantly, Watson began using the term Labyrinthodontia to refer to these groups. The name Temnospondyli was rarely used in the decades that followed. Swedish paleontologist Gunnar Säve-Söderbergh removed embolomeres from the group, narrowing its scope to rhachitomes and stereospondyls. His classification of labyrint... |
3,598 | 508 | 4 | 999 | 248 | 19 | 11 | 249 | ary history ==
=== Carboniferous and Early Permian ===
Temnospondyls first appeared in the Early Carboniferous around 330 million years ago (Mya). During the Carboniferous, temnospondyls included basal medium-sized forms such as Dendrerpeton or large semiaquatic forms such as Cochleosaurus. Other, more derived temno... |
3,590 | 520 | 4 | 998 | 248 | 20 | 11 | 248 | the Late Carboniferous.
=== Late Permian ===
During the Late Permian, increasing aridity and the diversification of reptiles contributed into a decline in terrestrial temnospondyls, but semiaquatic and fully aquatic temnospondyls continued to flourish, including the large Melosaurus of Eastern Europe. Other temnospon... |
3,314 | 564 | 4 | 997 | 247 | 21 | 11 | 247 | these animals dominated the freshwater ecosystems, evolving in a range of both small and large forms. During the Early Triassic (251.0 - 245.0 Mya) one group of successful long-snouted fish-eaters, the trematosauroids, even adapted to a life in the sea, the only known amphibians to do so with the exception of the moder... |
4,162 | 588 | 4 | 998 | 248 | 22 | 11 | 248 | the superficially very similar Metoposauridae. Metoposaurids are distinguished from capitosauroids by the positioning of their eye sockets near the front of their skulls. Another group of stereospondyls, the plagiosaurs, had wide heads with external gills, and adapted to life at the bottom of lakes and rivers. By this ... |
3,450 | 512 | 4 | 998 | 248 | 23 | 11 | 248 | had little diversity, as they were inhabited almost exclusively by metoposaurs.
The Triassic-Jurassic extinction event around 199.6 Mya led to the extinction of most Mesozoic temnospondyls. The brachyopoids survived, as well as a few capitosauroids and trematosauroids. While the latter two groups soon became extinct, b... |
4,018 | 556 | 4 | 999 | 248 | 24 | 11 | 249 |
Originally, temnospondyls were classified according to the structure of their vertebrae. Early forms, with complex vertebrae consisting of a number of separate elements, were placed in the suborder Rachitomi, and large Triassic aquatic forms with simpler vertebrae were placed in the suborder Stereospondyli. With the r... |
3,054 | 276 | 4 | 998 | 248 | 25 | 11 | 248 | Class Amphibia
Order Temnospondyli
Superfamily Edopoidea
Family Cochleosauridae (Chenoprosopidae)
Family Edopidae
Family Dendrerpetontidae
Suborder Euskelia
Superfamily Dissorophoidea
Family Amphibamidae
Family Branchiosauridae
Family Dissorophidae
Family Micromelerpetontidae
Superfamily Eryopoidea
Family Eryopidae
Fam... |
3,370 | 472 | 4 | 998 | 248 | 26 | 11 | 248 | auridae
Family Stenotosauridae
Infraorder Trematosauria
Superfamily Trematosauroidea
Superfamily Metoposauroidea
Superfamily Plagiosauroidea
Superfamily Brachyopoidea
Superfamily Rhytidosteoidea
=== Phylogeny ===
In one of the earliest phylogenetic analyses of the group, Gardiner (1983) recognized five characteristic... |
3,866 | 572 | 4 | 999 | 248 | 27 | 11 | 249 | 987), including the contact between the postparietal and exoccipital at the back of the skull, small projections (uncinate processes) on the ribs, and a pelvic girdle with each side having a single iliac blade. These shared characteristics are called synapomorphies.
Temnospondyls are placed as basal tetrapods in phylog... |
2,978 | 416 | 4 | 998 | 248 | 28 | 11 | 248 | pospondyls and place temnospondyls in a more basal position within the stem of Tetrapoda. Below is a cladogram from Laurin and Reisz (1999) placing Temnospondyli outside crown Tetrapoda:
Most phylogenetic analyses of temnospondyl interrelationships focus on individual families. One of the first broad-scale studies of t... |
3,566 | 496 | 4 | 998 | 248 | 29 | 11 | 248 | idea, 12 Capitosauria, 13 Trematosauria, 14 Metoposauroidea
The most basal group of temnospondyls is the superfamily Edopoidea. Edopoids have several primitive or plesiomorphic features, including a single occipital condyle and a bone called the intertemporal that is absent in other temnospondyls. Edopoids include the ... |
3,458 | 480 | 4 | 998 | 248 | 30 | 11 | 248 | They are almost 40 million years younger than other basal temnospondyls, implying a long ghost lineage of species that are not yet known in the fossil record.
In 2000, paleontologists Adam Yates and Anne Warren produced a revised phylogeny of more derived temnospondyls, naming several new clades. Two major clades were ... |
3,386 | 472 | 4 | 998 | 248 | 31 | 11 | 248 | Yates and Warren also named Dvinosauria, a clade of small aquatic temnospondyls from the Carboniferous, Permian, and Triassic. They placed Dvinosauria within Limnarchia, but more recent studies disagree on their position. For example, a 2007 study places them even more basal than euskelians, while a 2008 study keeps th... |
3,510 | 512 | 4 | 998 | 248 | 32 | 11 | 248 | named a third major clade of stereospondyls, the Rhytidostea. This group included more primitive stereospondyls that could not be placed in either Capitosauria or Trematosauria, and included groups like Lydekkerinidae, Rhytidosteidae, and Brachyopoidea. While Capitosauria and Trematosauria are still widely used, Rhytid... |
3,450 | 472 | 4 | 999 | 248 | 33 | 11 | 249 | hoids, which were grouped with dvinosaurs. The clade including Eryopidae and Stereospondylomorpha was named Eryopiformes. In addition, Schoch named the clade containing all temnospondyls except edopoids Eutemnospondyli and reinstated the name Rhachitomi for the clade containing all temnospondyls except edopoids and den... |
3,566 | 512 | 4 | 998 | 248 | 34 | 11 | 248 | the origin of modern amphibians.
One is that they evolved from dissorophoid temnospondyls. Another is that they evolved from lepospondyls, most likely the lysorophians. A third hypothesis is that caecilians descended from lepospondyls and frogs and salamanders evolved from dissorophoids.
Recently, the theory that temno... |
3,494 | 532 | 4 | 998 | 248 | 35 | 11 | 248 | . Calcification normally proceeds downward to the base of the tooth, but calcification from the tip stops abruptly in pedicellate teeth. Calcification resumes at the base, leaving an area in the center of the tooth uncalcified. This pattern is seen in living amphibians and fossils.
The dissorophoid family Amphibamidae ... |
3,770 | 584 | 4 | 998 | 248 | 36 | 11 | 248 | the presence of pedicellate teeth in its jaws has led some paleontologists to conclude soon after its naming that it was a relative of modern amphibians. It was first described as a "protolissamphibian", and the specific name annectens means "connecting" in reference to its inferred transitional position between temnos... |
3,782 | 580 | 4 | 997 | 247 | 37 | 11 | 247 | primarily semiaquatic, they had the ability to feed on land. Later, eryopoids and dissorophoids, some well adapted to terrestrial life, also fed on land. Some eryopoids became better adapted toward life in water, and shifted their diets toward aquatic organisms. The first primarily aquatic feeders were archegosaurs in ... |
3,750 | 604 | 4 | 999 | 249 | 38 | 11 | 249 | bone pushes forward and causes the lower jaw to protrude outward. Other stereospondyls probably also lifted their skulls, but they are not as well adapted for such movement. D.M.S. Watson was the first to suggest skull lifting as a means of feeding in temnospondyls. He envisioned that Mastodonsaurus, a much larger temn... |
3,810 | 524 | 4 | 998 | 248 | 39 | 11 | 248 | suction feed by rapidly opening its mouth.
Unlike semiaquatic temnospondyls, terrestrial temnospondyls have skulls that are adapted for biting land-living prey. The sutures between the bones of the skull in the dissorophoid Phonerpeton are able to withstand a high degree of compression. Compressive forces would have be... |
4,010 | 648 | 4 | 998 | 248 | 40 | 11 | 248 | in water while males released sperm to fertilize them. Several fossils were described from the Early Permian of Texas in 1998 that may be egg masses of dissorophoid temnospondyls. They were the first known fossils of amphibian eggs. The fossils consist of small disks with thin membranes that are probably vitelline memb... |
3,942 | 596 | 4 | 999 | 248 | 41 | 11 | 249 | yl, the dvinosaur Trimerorhachis, may have brooded young in an area between the gills called the pharyngeal pouch. Small bones belonging to younger Trimerorhachis individuals have been found in these pouches. The living Darwin's Frog is also a mouth brooder and would be the closest modern analogue to Trimerorhachis if ... |
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