The trachyte of the Drachenfels was probably the neck of a volcano which burst through the fundamental schists of the Devonian period.
"Volcanoes: Past and Present" by Edward Hull
Not one solitary species of fish now in existence is to be found in the Devonian or Silurian formations.
"The Voice of Science in Nineteenth-Century Literature" by Various
It was not until Devonian and Carboniferous times that the plants became very abundant, as far as the geological records go.
"The Christian View of the Old Testament" by Frederick Carl Eiselen
Tottenham Court Road ,, 1,064 ,, ,, Devonian.
"Island Life" by Alfred Russel Wallace
Devonian rocks in Ohio have yielded fine fossils of gigantic fishes and sharks.
"Earth and Sky Every Child Should Know" by Julia Ellen Rogers
Impressions of rain-marks have been found in the shales of the coal measures and Devonian system.
"The Origin of the World According to Revelation and Science" by John William Dawson
The whole region is underlain by nearly horizontal and undisturbed rocks of the Palaeozoic from the Devonian downward.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 2" by Various
Devonian strata formed in deep seas, 117.
"Principles of Geology" by Charles Lyell
They appear to indicate a Devonian age.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 5" by Various
Occur exclusively in Palaeozoic strata from Devonian upwards.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 6" by Various
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Thus, the “Big Five” extinctions occurred at the ends of the Ordivician, Devonian, Permian, Triassic, and Cretaceous epochs, and it is estimated that each of them killed at least 70% of all existing species [184].
Biological Evolution and Statistical Physics
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