Louie M. Knight Dutton, Devonshire
“ The Upper Devonian is less fossiliferous, but contains some large trilobites, various marine shells, and some land-plants.The South Devonian, which covers nearly all South Devon and a large part of Cornwall, is somewhat different in character, consisting chiefly of slates, with coralline limestones, varied by volcanic outcrops or elvans—a word said to be of Cornish origin, and meaning "white rock." To judge from its fossils, it was deposited in deeper water than the contemporary beds in the north of the county. The Lower and Middle beds are also far richer in animal remains ”
