"Silurian" Quotes from Famous Books
 ... the lower vertebrata (Elasmobranch and Ganoid fishes) occur, indeed, in early strata (upper Silurian); but still far from the earliest in which some of the invertebrata are found. The general statement in the text applies chiefly to the more highly organised ...
— The Scientific Evidences of Organic Evolution • George John Romanes
... "middle life" or those between the most ancient and the Cenozoic, or recent forms of life. The periods are lesser divisions of the eras. In the Proterozoic, there are two periods, viz.: the Archaean and the Algonkian. The Paleozoic has six periods, viz.: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. The Mesozoic era has three periods, the Triassic, Jurassic and Cretaceous, while the Cenozoic era names five periods,—the Eocene, Oligocene, Miocene, Pliocene ...
— The Grand Canyon of Arizona: How to See It, • George Wharton James
... to the uranium haloes of the mica of County Carlow.[1] Results for the age of the halo of from 20 to 400 millions of years have been obtained. This mica was probably formed in the granite of Leinster in late Silurian or in ...
— The Birth-Time of the World and Other Scientific Essays • J. (John) Joly
... lithological evidence; yet his reasoning all through Siluria, shows that he still thinks it natural to expect formations of the same age to be chemically similar, even in remote regions. For example, in treating of the Silurian rocks of South Scotland, he says:—"When traversing the tract between Dumfries and Moffat, in 1850, it occurred to me, that the dull reddish or purple sandstone and schist to the north of the former town, which so resembled the bottom rocks of Longmynd, ...
— Essays: Scientific, Political, & Speculative, Vol. I • Herbert Spencer
... felspathic porphyry and ashes. The same formation occurs just within the county border at Cerrig-y-Druidion, Langum, Bettys-y-coed and in the Fairy Glen. Northwards from the Ceiriog to the limestone fringe at Llandrillo the Wenlock shale of the Silurian covers the entire mass of the Hiraethog and Clwydian hills, but verging on its western slopes into the Denbighshire grit, which may be traced southward in a continuous line from the mouth of the Conway as far as Llanddewi Ystrad ...
— Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 2 - "Demijohn" to "Destructor" • Various
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