Around the coast there is a raised shelf of limestone which was undoubtedly a coral reef.
They are coral islands of comparatively recent elevation, and in no place rise more than 250 ft.
To the west lie the small groups of coral islets - Mopiha (Lord Howe), Ura (Scilly) and Bellingshausen (discovered by Otto von Kotzebue, 1824).
The Great Barrier Reef forms the prominent feature off the north-east coast of Australia; its extent from north to south is 1200 m., and it is therefore the greatest of all coral reefs.
The shores are covered with coral; earthquakes and tidal waves are frequent, the latter not taking the form of bores, but of a sudden steady rise and equally sudden fall in the level of the sea; the climate is rather tropical than temperate, but sickness is almost unknown among the residents.
Fishing and trawling are carried on chiefly off the Italian (especially Ligurian, Austrian and Tunisian coasts; coral is found principally near Sardinia and Sicily, and sponges almost exclusively off Sicily arid Tunisia in tile neighborhood of Sfax.
Sardinian coral commands from 3 to 4 per kilogramme (2.204 Ib), and is much more valuable than the Sicilian coral.
The fishing is largely carried on by boats from Tone del Greco, in the Gulf of Naples, where the best coral beds are now exhausted.
The lagoon fisheries are also of great importance, more especially those of Comacchio, the lagoon of Orbetello and the Mare Piccolo at Taranto &c The deep-sea fishing boats in 1902 numbered 1368, with a total tonnage of 16,149; 100 of these were coral-fishing boats and 111 sponge-fishing boats.
A vast variety of trinketsin coral, glass, lava, &c.is exported from Italy, or carried away by the annual host of tourists.
The scenery is everywhere strikingly beautiful and varied, and the coral beds of the more secluded bays in its harbours are conspicuous for their exquisite colouring.
60), where the interspaces between the coenosarcal tubes are filled up with calcareous matter, or coenosteum, replacing the chitinous perisarc. The result is a stony, solid mass, which contributes to the building up of coral reefs.
Tetuaroa and Tubai, besides the three western Leeward Isles, are coral atolls.
There are raised coral beds high up the mountains, and lava occurs in a variety of forms, even in solid flows; but all active volcanic agency has so long ceased that the craters have.
Round most of the islands there is a luxuriant coral growth; but, as the reefs lie at no great distance, and follow the line of the coast, the inter-island channels are comparatively safe.
Thus, prepared oystershells, coral, pearls, crabs' " eyes " and burnt hart's horn were regarded as specifics in different complaints, in ignorance of the fact that they all contain, as the chief ingredients, calcium phosphate and carbonate.
The lagoon, which is enclosed by two coral barriers and accessible to the largest vessels on the north side, forms one of the finest natural harbours in the world.
See Geographical Journal, passim; and Atoll of Funafuti: Borings into a Coral Reef (Report of Coral Reef Committee of Royal Society, London, 1904).
With the exception of Rose Island, which is an uninhabited coral islet 70 m.
Coral reefs protect the coasts in many parts; they are frequently interrupted, but the passages through them are often difficult of navigation.
Another group of islands consists of elevated masses of submarine volcanic deposits, upon some of which coral-reef limestone forms a more or less complete covering; such are Tonumeia and the Nomuka group (Mango, Tonua, Nomuka-iki).
The Vavau group consists entirely of coral limestone, which is occasionally crystalline, and contains stalactitic caves of great beauty.
The order is well represented in Britain by 18 genera, which include several species of Orchis: Gymnadenia (fragrant orchis), Habenaria (butterfly and frog orchis), Aceras (man orchis), Hermin- ium (musk orchis), Ophrys (bee, spider and fly orchis), Epipactis (Helleborine), Cephalanthera, Neottia (bird's-nest orchis), one of the few saprophytic genera, which have no green leaves, but derive their nourishment from decaying organic matter in the soil, Listens (Tway blade), Spiranthes (lady's tresses), Malaxis (bog-orchis), Liparis (fen-orchis), Corallorhiza (coral root), also a saprophyte, and Cypripedium (lady's slipper), represented by a single species now very rare in limestone districts in the north of England.
The Laccadives and Maldives are groups of small coral islands, situated along the 73rd meridian, at no great distance from the Indian peninsula, on which they have a political dependency.
The Squamipennes, or scaly-finned fishes, are principally found in the seas of southern Asia, and especially near coral reefs.
Desis lives invariably between tide-marks upon the rocks and coral reefs, and may be found at low tide either crawling about upon them or swimming in tidal pools and feeding upon small fish or crustaceans.
The vessels contained a dark dust, apparently disintegrated ashes, small pieces of bone, and a number of small pieces of jewelry in gold, silver, white and red cornelian, amethyst, topaz, garnet, coral and crystal.
The rivers and neighbouring seas seem to be well stocked with fish, and especial mention must be made of the turtles, flying-fish, and brilliant I coral-fish which swarm in the waters warmed by the Kurosiwo current, the gulf-stream of the Pacific. Shell-fish form an important article of diet to both the Chinese and the aborigines along the coast - a species of Cyrena, a species of Tapes, Cytheraea petechiana and Modiola teres being most abundant.
Close to the coast the soil is for the most part a coral sand.
On the foothills and in the less rugged mountain districts there is a thin but rich clay soil derived from coral limestone.
All these stones were of course imported, as the Babylonian had no stone (except a rough coral rag) at hand as the Egyptian had.
It is not at all certain that the masses on which coral reefs are built consist entirely of the remains of the skeletons of reef-forming organisms and it is probable that chemically precipitated carbonate of lime predominates.
Interesting speculations as to the periods of origin of great coral reefs have been made by Wayland Vaughan, Andrews and Daly and Humphreys.
Bermudas) and coral reefs.
Side of the island there are long chains of islets and reefs and coral keys (of which it is estimated there are 1300), which limit access to probably half of the coast, and on the N.
From this point a zone of upheaved coral rocks skirts the shore for some distance.
The town occupies the whole of a small coral island at the mouth of Mossoril Bay.
The only stone building in southern Babylonia is the town wall of Eridu (Abu Shahrein), which is built of rude lumps of a local coral rag.
It is covered with a layer of thin, dry soil, through the slow weathering of the coral rocks.
Next to these come the coral islands Nomuka and Lifuka in the Hapai group; Tofua, 2846 ft., Late or Lette, 1800 ft.
Two other United States warships, "Trenton" and "Vandalia," were beaten to pieces on the coral reef; and the German warships "Olga" and "Eber" were wrecked with great loss of life.
The terrigenous deposits consist of blue muds, red muds (abundant along the coast of Brazil, where the amount of organic matter present is insufficient to reduce the iron in the matter brought down by the great rivers to produce blue muds), green muds and sands, and volcanic and coral detritus.