Pre-historic Skulls " 459 Primitive Sculpture " 481 TABLE OF GEOLOGICAL HISTORY. Non-Geological readers will find in the following table a condensed explanation of the more important technical terms used in the following pages. The order is from older to newer. GREATER SYSTEMS OF CHARACTERISTIC FOSSILS. PERIODS. FORMATIONS. Archæan or Eozoic Pre-Laurentian Laurentian Protozoa Protophyta Palæozoic Huronian { Crustaceans Algæ Cambrian { Molluscs Cryptogamous Cambro-Silurian[A] { Worms and Silurian[B] { Corals, etc, Gymnospermous Devonian Fishes Plants. Carboniferous Amphibians Permian Mesozoic Triassic { Reptiles Pines and Jurassic { Birds Cycads Cretaceous { Earliest Mammals. Trees of modern types. Kainozoic or Tertiary Eocene Higher Mammals Miocene of extinct forms Pliocene Recent Mammals Modern Plants, Pleistocene and Modern Man. [A] Ordovician of Lapworth. [B] Salopian of Lapworth. _THE STARTING-POINT._ DEDICATED TO THE MEMORY OF PROF. ROBERT JAMESON, Of the University of Edinburgh, my first Teacher in Geology, whose Lectures I attended, and whose kind Advice and Guidance I enjoyed, in the Winter of 1840-1841. Headlands and Spurs--Popular Papers on Leading Topics--Revisiting Old Localities--Dedications--General Scope of the Work CHAPTER I. _THE STARTING-POINT._