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according action afford animal appears atolls Bank barrier beach become beds Bermudas bottom branches called causes channels character coast common consists containing continuous coral islands coral reefs covered currents deep deposits depth described diameter distance east elevation evidence existence extent facts fathoms Feejees feet figure five Florida formation four give gradually Group growing growth half harbor height hundred inches increase kind lagoon land larger less lime limestone living margin masses material miles nearly observed occur ocean origin outer Pacific Paumotus platform polyps portions present probably range region remarkable represents result rise rock sand shallow shells shores side similar slope sometimes species streams structure subsidence surface tentacles tide Tongatabu trees twenty unchanged usually Verrill volcanic waves whole wide zoöphytes
283 ページ - How much of the poetry or literature of Europe would be intelligible to persons whose ideas had expanded only to the limits of a coral island ;— who had never conceived of a surface of land above half a mile in breadth,— of a slope higher than a beach, — of a change of seasons beyond a variation in the prevalence of rains...
226 ページ - ... feet. The ocean is thus the architect, while the coral polyps afford the material for the structure : and when all is ready, it sows the land with seed brought from distant shores, covering it with verdure and flowers. The growth of the reefs and islands around high lands, is the same as here described for the atoll. The reef rock, in all cases, is mainly a result of accumulations of coral and shell debris.
18 ページ - Coral is never, therefore, the handiwork of the manyarmed polyps; for it is no more a result of labor than bone-making in ourselves. And again, it is not a collection of cells into which the coral animals may withdraw for concealment any more than the skeleton of a dog is its house or cell ; for every part of the coral — or corallum, as it is now called in science — of a polyp, in most reefmaking species, is enclosed within the polyp, where it was formed by the secreting process.
281 ページ - An occasional log drifts to their shores, and at some of the more isolated atolls, where the natives are ignorant of any land but the spot they inhabit, they are deemed direct gifts from a propitiated deity.
218 ページ - Very erroneous ideas prevail, respecting the appearance of a bed or area of growing corals. The submerged reef is often thought of as an extended mass of coral, alive uniformly over its upper surface, and, by this living growth, gradually enlarging upward : and such preconceived views, when ascertained to be erroneous by observation, have sometimes led to skepticism with regard to the zoophytic origin of the reef-rock.
118 ページ - Upon the reefs enclosing the harbor of Rewa, (Viti Lebu,) where a large river three hundred yards wide empties, which during freshets enables vessels at anchor two and a half miles off its mouth to dip up fresh water alongside, there is a single porous species of Madrepora, (M. cribripora,) growing here and there in patches over a surface of dead coral rock or sand. In similar places about other regions, species of Porites are most common.
7 ページ - His work on coral-reefs appeared in 1842, when my report on the subject was already in manuscript. It showed that the conclusions on other points, which we had independently reached, were for the most part the same. The principal points of difference relate to the reason for the absence of corals from some coasts, and the evidence therefrom as to changes of level, and the distribution of the oceanic regions of elevation and subsidence — topics which a wide range of travel over the Pacific brought...
326 ページ - ... still in progress ; the changes indicated are of a contrary character. The results to which we have here been led obviously differ, in many particulars, from the deductions of Mr Darwin. 2. Elevations of modern eras in the Pacific. Since the period of subsidence, the history of which has occupied us in the preceding pages, there has been no equally general elevation. Yet various parts of the ocean bear evidence of changes confined to particular islands or groups of islands.
225 ページ - The coral world, as we thus perceive, is planted, like the land, with a variety of shrubs and smaller plants, and the elements and natural decay are producing gradual accumulations of material, like those of vegetation. The history of the growing reef has consequently its counterpart among the ordinary occurrences of the land about us. The progress of the coral formation is like its commencement. The same causes continue, with similar results, and the reader might easily supply the details from the...