The Influence of Silurian-Devonian Climates on the Rise of Air-Breathing Vertebrates.

beyond what was laid down by the rivers in time of flood to maintain their grade across the sinking basins was carried through to the shallow sea which lay on the surface of the continent to the southwest. The relations were somewhat similar to those which now prevail between the ranges of the North American Cordillera and the Tertiary basins which lay between them and especially on the west between the Sierra Cascade chains and the Coast Ranges. The Great Valley of California may therefore in the present epoch, both in physiography and in climate be cited as a striking illustration of the nature of the Old Red Sandstone basins.