"like the backs of sea beasts in a Devonian dawn"

The Back of a Sea Beast
Public DomainThe Back of a Sea Beast - Credit: National Oceanic and Atmospheric Administration

The Devonian was a geological period stretching from 405 to 345 million years ago.  It was characterized by the dominance of fishes and the advent of amphibians and ammonites.


Creative Commons Attribution Share Alike"Devonian" Black Mountains - Credit: Philip Halling