THE AGE OF REPTILES
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great cataclysmal climatic change. When next we find abundant traces of the land plants and the land animals of the earth, this great multitude of reptile species had gone. For the most part they have left no descendants. They have been "wiped out." The pterodactyls have gone absolutely; of the plesiosaurs and ichthyosaurs none is alive; the mosasaurs have gone; of