CONTENTS. 



PART I. THE PROTOPHYTON. 



CHAPTER I. 



The Natural History of a Grain of Wheat ... page 1 7 



CHAPTER II. 



The Natural History of a Grain of Wheat (continued} 7 12 



CHAPTER III. 



The Natural History of a Grain of Wheat (concluded} 1218 



PAET II. THE PROTOZOON. 



CHAPTER I. 

 The Protozoa : The Gregarina and Infusoria 1925 



CHAPTER II. 

 The Infusoria (continued} 2633 



CHAPTER III. 

 The Rhizopoda 3340 



CHAPTER IV. 



The Rhizopoda (continued} The Foraminif era 4048 



CHAPTER V. 

 The Foraminifera in Time 4858 



CHAPTER VI. 



The Radiolaria The Sponges , 5868 



