TABLE OF CONTENTS 



PAGE 



INTRODUCTION , . . . ix 



CHAPTEE I 

 THE PROBLEM: THE MODE OF ITS SOLUTION . . . 1 



The question. The two theories of man's origin. The argument purely 

 historical. Means of tracing man's ancestry and history. Classification. 

 Ontogenesis and Phylogenesis. 



CHAPTEE II 



PROTOZOA TO WORMS : CELLS, TISSUES, AND ORGANS . 32 



Amoeba : Its anatomy and physiology. Development of the cell. 

 Hydra : The development of digestive and reproductive organs, and of 

 tissues. Forms intermediate between amceba and hydra : Magosphsera, 

 volvox. Embryonic development. Turbellaria : Appearance of a body 

 wall, of ganglion, and nerve-cords. 



CHAPTEE III 



WORMS TO VERTEBRATES: SKELETON AND HEAD . 55 



Worms and the development of organs. Mollusks : The external protec- 

 tive skeleton leads to degeneration or stagnation. Annelids and arthro- 

 pods : The external locomotive skeleton leads to temporary rapid advance, 

 but fails of the goal. Its disadvantages. Vertebrates : The internal loco- 

 motive skeleton leads to backbone and brain. Reasons for their dominance 

 The primitive vertebrate. 



