CONTENTS xi 



PART II 

 CHAPTER I 



PAGE 



AMCEBA 'UNICELLULAR AND MULTICELLULAR ANIMALS . . 22Q 

 PRACTICAL DIRECTIONS 238 



CHAPTER II 



SPH;RELLA AND EUGLENA MONADS AND BACTERIA DIF- 

 FERENCES BETWEEN ANIMALS AND PLANTS SAPRO- 

 PHYTES 240 



PRACTICAL DIRECTIONS 259 



CHAPTER III 



PARAMCECIUM : VORTICELLA AND ITS ALLIES COLONIAL 



ORGANISMS 26l 



PRACTICAL DIRECTIONS 277 



CHAPTER IV 



OPALINA I MONOCYSTIS -PARASITISM BIOGENESIS AND 



ABIOGENESIS -CLASSIFICATION OF THE UNICELLULAR 



ORGANISMS EXAMINED 280 



PRACTICAL DIRECTIONS 293 



CHAPTER V 



t 



HYDRA I OBELIA SYMBIOSIS ALTERNATION OF GENERA- 

 TIONS -CHARACTERS OF THE PHYLUM CCELENTERATA . 294 

 PRACTICAL DIRECTIONS 322 



CHAPTER VI 



THE EARTHWORM I NEREIS CHARACTERS OF THE PHYLUM 



ANNULATA 326 



PRACTICAL DIRECTIONS 354 



CHAPTER VII 



THE CRAYFISH -CHARACTERS OF THE PHYLUM ARTHROPODA 360 

 PRACTICAL DIRECTIONS 386 



