Fossils of Xenophanes

"And Xenophanes opines that there was once a mixture of earth with the sea, and that in time it was freed from moisture, asserting in proof of this that shells are found in the centre of the land and on mountains, and that in the stone quarries of Syracuse were found the impress of a fish and of seals, and in Paros the cast of an anchor below the surface of the rock and in Malta layers of all sea-things. And he says that these came when all things were of old time buried in mud, and that the impress of them dried in the mud; but that all men were destroyed when the earth being cast into the sea became mud, and that it again began to bring forth and that this catastrophe happened to all the ordered worlds." -- Hippolytus, Refutation of All Heresies, 2nd century