CHAPTER XI.

The Devonian period--Relations between the Old Red Sandstone and the marine Devonian deposits--The Old Red Sandstone of Scotland--The Devonian strata of Devonshire--Sequence and subdivisions of the Devonian deposits of North America--Life of the period--Plants--Protozoa--Corals-Crinoids--Pentremites-- Annelides--Crustaceans--Insects--Polyzoa--Brachiopods--Bivalves-- Univalves--Pteropods--Cephalopods--Fishes--General divisions of the Fishes--Palæontological evidence as to the independent existence of the Devonian system as a distinct formation--Literature.