To geologists who may glance at the following pages, I would say that, amidst much that is familiar, they will find here and there some facts which may be new to them, as well as some original suggestions and conclusions as to the relations of things, which though stated in familiar terms, I have not advanced without due consideration of a wide range of facts, To the general reader I have endeavoured to present the more important results of geological investigation divested of technical difficulties, yet with a careful regard to accuracy of statement, and in such a manner as to invite to the farther and more precise study of the subject in nature, and in works which enter into technical details. I have endeavoured as far as possible to mention the authors of important discoveries; but it is impossible in a work of this kind to quote authority for every statement, while the omission of much important matter relating to the topics discussed is also unavoidable. Shortcomings in these respects must be remedied by the reader himself, with the aid of systematic text-books. Those who may desire any farther explanation of the occasional allusions to the record of creation in Genesis, will find this in my previously published volume entitled "Archaia." J. W. D, McGill College, Montreal, _January, 1873_. CONTENTS. PAGE Chapter I.--The Genesis Of The Earth. Uniformity and Progress.--Internal Heat.--Nebular Theory.--Probable Condition of the Primitive World 1 Chapter II.--The Eozoic Ages. The Laurentian Rocks.--Their Character and Distribution.--The Conditions of their Deposition.--Their Metamorphism.--Eozoon Canadense.--Laurentian Vegetation 17 Chapter III.--The Primordial or Cambrian Age. Connection of the Laurentian and Primordial.--Animals of the Primordial Seas.--Lingula, Trilobites, Oldhamia, etc.--The terms Cambrian and Silurian.--Statistics of Primordial Life 36 Chapter IV.--The Silurian Ages. Geography of the Continental Plateaus.--Life of the Silurian.--Reign of Invertebrates.--Corals, Crinoids, Mollusks, Crustaceans.--The First Vertebrates. Silurian Fishes.--Land Plants 56 Chapter V.--The Devonian or Erian Age. Physical Character of the Age.--Difference of Deposits in Marginal and Continental Areas.--Specialisation of Physical Geography.--Corals, Crustaceans, Fishes, Insects, Plants 81 Chapter VI.--The Carboniferous Age. Perfection of Palæozoic Life.--Carboniferous Geography.--Colours of Sediments.--Vegetation.--Origin of Coal.--Land Life.--Reptiles, Land Snails, Millipedes, etc.--Oceanic Life 109 Chapter VII.--The Permian Age.