CONTENTS. 



Index .. .. .. .. .. .. .. page xx i 



PART I. 



The Nature and Source of the Vital Forces, and of 

 Organizable Matter. 



CHAPTER I. 



Pages 



The Persistence of Force : Correlation of the Vital and 



Physical Forces 1-49 



CHAPTER II. 



The 'Vital Principle': Nature of Life .. .. .. 5O~79 



CHAPTER III. 



Nature of Organizable Materials and of lowest Living Things 80-128 



CHAPTER IV. 



Relations of Animal, Vegetable, and Mineral Kingdoms : 



Theories of Organization .. .. .. .. 129-168 



CHAPTER V. 

 Modes of Origin of Reproductive Units and of Cells .. 169-239 



