CONTENTS OF VOL. II. 



PAGE 



xiii 



List of Plates 

 List of Wood( 

 List of Genetic Tables ... ... ... ••• — XV11 



• • * 



List of Woodcuts 



» • 



CHAPTER XV. 



THE DURATION OF HUMAN TRIBAL HISTORY. 



Comparison of Ontogenetic and Phylogenetic Periods of Time. — Dura- 

 tion of Germ -history in Man and in Different Animals. — Extreme 

 Brevity of the Latter in Comparison with the Immeasurable Long 

 Periods of Tribal History. — Relation of this Rapid Ontogenetic 

 Modification to the Slow Phylogenetic Metamorphosis. — Estimate 

 of the Past Duration of the Organic "World, founded on the Relative 

 Thickness of Sedimentary Rock-strata, or Neptunian Formations. 

 — The Five Main Divisions in the Latter : I. Primordial, or 

 Archilithic Epoch. II. Primary, or Palaeolithic Epoch. III. Second- 

 ary, or Mesolithic Epoch. IV. Tertiary, or Caenolithic Epoch. 

 V. Quaternary, or Anthropolithic Epoch. — The Relative Duration 

 of the Five Epochs. — The Results of Comparative Philology as 

 Explaining the Phylogeny of Species. — The Inter-relations of the 

 Main Stems and Branches of the Indo-Germanic Languages are 

 Analogous to the Inter-relations of the Main Stems and Branches 

 of the Vertebrate Tribe. — The Parent Forms in both Cases are 

 Extinct. — The Most Important Stages among the Human An- 

 cestral Forms. — Monera originated by Spontaneous Generation. 

 —Necessity of Spontaneous Generation 



