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 PERIODS. | SYSTEMS OF FORMATIONS. | CHARACTERISTIC FOSSILS. | ||
| 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.