viii CONTENTS. 



PAGE 



CHAPTER X. DEVELOPMENT 644 



Metamorphosis 651 



Parthenogenesis and Alternation of Genera- 

 tions 652 



Dimorphism and Polymorphism 654 



Individuality 656 



Hybridity 657 



XI. THE GEOGRAPHICAL DISTRIBUTION OF ANIMALS 658 



Means of Dispersal 660 



Division of the Earth into Faunae 661 



Distribution of Marine Animals 664 



Chief Zoological Fauna; of the Earth 666 



XII. THE GEOLOGICAL SUCCESSION OF ANIMALS 668 



XIII. THE ORIGIN OF SPECIES 671 



XIV. PROTECTIVE RESEMBLANCE 675 



XV. INSTINCT AND REASON IN ANIMALS 680 



XVI. GLOSSARY C89 



XVIL INDEX . 697 



