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A Short History of The World

These fishes increase greatly in the next division of rocks, the rocks known as the Devonian system. They are so prevalent that this period of the record of the rocks has been called the Age of Fishes. Fishes of a pattern now gone from the earth, and fishes allied to the sharks and sturgeons of to-day, rushed through the waters, leapt in

SHARKS AND GANOIDS OF THE DEVONIAN PERIOD

the air, browsed among the seaweeds, pursued and preyed upon one another, and gave a new liveliness to the waters of the world. None of these were excessively big by our present standards. Few of them were more than two or three feet long, but there were exceptional forms which were as long as twenty feet.