CONTENTS 



CHAPTER I 



I'AGE 



THE EVIDENCE FOR EVOLUTION ...... i 



CHAPTER II 

 UNICELLULAR AND MULTICELLULAR ANIMALS ... 23 



CHAPTER III 



THE WORMS AND SOME OF THEIR POSTERITY . . . 58 



CHAPTER IV 

 THE EARLY VERTEBRATES AND THE FISHES . . . . 79 



CHAPTER V 

 THE CONQUEST OF THE LAND . . . . . .104 



CHAPTER VI 

 THE MAMMALS AND MAN . . . . . 123 



FOR many of the illustrations the Publishers are indebted 

 to the Deutsche Verlags-Anstalt (from Giinther's Vom 

 Urtier zum Menschen} and Herr Wilhelm Engelmann 

 (from Haeckel's Anthropogenic}. 



vii 



