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Keywords from Image Description:
Cephalaspis Lyellii. en Cephalaspis lyellii Old Red Sandstone Scotland Nicholson The ancient lifehistory of the Earth comprehensive outline of the principles and leading facts of paleaontological science Edinbourgh London WIlliam Blackwood and sons org page Reprint Henry Alleyne Nicholson drawn after Page PDold Cephalaspis Silurian