CONTENTS 



CHAPTEE I 



WHAT ARE " SPECIES " AND WHAT IS JIEANT BY THEIR 



" ORIGIN " 



Definition of species — Special creation — The early transmutationists — 

 Scientific opinion before Darwin — The problem before Darwin — The 

 change of opinion effected by Darwin — The Darwinian theory — Pro- 

 posed mode of treatment of the subject . . . Pages 1-13 



CHAPTER II 



THE STRUGGLE FOR EXISTENCE 



Its importance — The struggle among plants — Among animals — Illustrative 

 cases — Succession of trees in forests of Denmark — The struggle for 

 existence on the Pampas — Increase of organisms in a geometrical 

 ratio — Examples of rapid increase of animals — Kapid increase and 

 •\vide spread of plants — Great fertility not essential to rapid increase 

 — Struggle between closely allied species most severe — The ethical 

 aspect of the struggle for existence . . . 14-40 



CHAPTER III 



THE VARIABILITY OF SPECIES IN A STATE OF NATURE 



Importance of variability — Popular ideas regarding it — Variability of the 

 lower animals — The variability of insects — Variation among lizards — 



