Discourses Biological and Geological: Essays |
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Page 280
... Devonian sandstones to make oath they never saw a fish or a mollusk , though all the world knows there were plenty in their time . But then it is urged that , though the Devonian rocks in one part of the world exhibit no fossils , in ...
... Devonian sandstones to make oath they never saw a fish or a mollusk , though all the world knows there were plenty in their time . But then it is urged that , though the Devonian rocks in one part of the world exhibit no fossils , in ...
Page 293
... Devonian and Carboniferous Pleuracanthus , which differs no more from existing Sharks than these do from one another . Again , vast as is the number of undoubtedly Ganoid fossil Fishes , and great as is their range in time , a large ...
... Devonian and Carboniferous Pleuracanthus , which differs no more from existing Sharks than these do from one another . Again , vast as is the number of undoubtedly Ganoid fossil Fishes , and great as is their range in time , a large ...
Page 294
Essays Thomas Henry Huxley. older and the younger Fishes ; the former , the Devonian Ganoids , being almost all members of the same ... Devonian Epoch . " tion of the oldest forms differed nearly so much from 294 IX GEOLOGICAL ...
Essays Thomas Henry Huxley. older and the younger Fishes ; the former , the Devonian Ganoids , being almost all members of the same ... Devonian Epoch . " tion of the oldest forms differed nearly so much from 294 IX GEOLOGICAL ...
Page 301
... Devonian Ganoids , though genera . almost all members of the same sub - order as Polypterus , and presenting numerous important re- semblances to the existing genus , which possesses biconglave vertebræ , are , for the most part ...
... Devonian Ganoids , though genera . almost all members of the same sub - order as Polypterus , and presenting numerous important re- semblances to the existing genus , which possesses biconglave vertebræ , are , for the most part ...
Page 348
... Devonian Ganoids are closely related to Polypterus and to Lepidosiren . But when we turn to the higher Vertebrata , the results of recent investigations , however we may sift and criticise them , seem to me to leave a clear balance in ...
... Devonian Ganoids are closely related to Polypterus and to Lepidosiren . But when we turn to the higher Vertebrata , the results of recent investigations , however we may sift and criticise them , seem to me to leave a clear balance in ...
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Common terms and phrases
Abiogenesis accumulation Anchitherium ancient animals appear Arctogæal Atlantic body bottom calcareous carbonic acid Carboniferous Carnivora causes Cetacea chalk cilium coal contains creatures cretaceous deep sea deposit depths Devonian Diatoms distribution doctrine doubt dredge dry land earth Eocene evidence existence fact fathoms fauna fermentation fish fluid Foraminifera formation forms fossil genera geological speculation geologists germs give rise globe Globigerina ooze gradually Heteromita Hipparion hypothesis knowledge known less living lobster Mammalia mammals matter Mediterranean Mesozoic microscope Miocene Miocene epoch modern modification monad naturalist nature observed ocean organisms oxygen paleontology particles Pébrine peculiar period physical plants present day protoplasm proved Radiolaria red clay regions remains rocks scientific sea-bottom shells silicious Silurian similar species sporangia spores structure substance sugar suppose surface tertiary things tion Torula trawl Triassic types Ungulata Uniformitarianism vegetable whole Wyville Thomson Xenogenesis yeast zoology zoospores
Popular passages
Page 14 - Globigerince, with the granules which have been mentioned, and some few other calcareous shells ; but a small percentage of the chalky mud — perhaps at most some five per cent, of it — is of a different nature, and consists of shells and skeletons composed of silex, or pure flint. These silicious bodies belong partly to the lowly vegetable organisms which are called Diatomaceoe, and partly to the minute, and extremely simple, animals, termed Radiolaria. It...
Page 13 - Globigerince of every size, from the smallest to the largest, are associated together in the Atlantic mud, and the chambers of many are filled by a soft animal matter. This soft substance is, in fact, the remains of the creature to which the Globigerina shell, or rather skeleton, owes its existence — and which is an animal of the simplest imaginable description. It is, in fact, a mere particle of living jelly, without defined...
Page 22 - This is a kind of shell-fish, with a shell composed of two pieces, of which, as in the oyster, one is fixed and the other free. " The upper valve is almost invariably wanting, though occasionally found in a perfect state of preservation in the white chalk at some distance. In this case, we see clearly that the sea-urchin first lived from youth to age, then died and lost its spines, which were carried away. Then the young Crania adhered to the bared shell, grew and perished in its turn; after which,...
Page 32 - Indians. Crocodiles of modern type appear ; bony fishes, many of them very similar to existing species, almost supplant the forms of fish which predominate in more ancient seas ; and many kinds of living shell-fish first become known to us in the chalk.
Page 244 - But the great tragedy of Science — the slaying of a beautiful hypothesis by an ugly fact...
Page 6 - Or, to take a more familiar example, the fur on the inside of a teakettle is carbonate of lime, and, for anything chemistry tells us to the contrary, the chalk might be a kind of gigantic fur upon the bottom of the earth-kettle, which is kept pretty hot below.