CONTENTS xi 



PART II 

 CHAPTER I 



PAGE 



AMCEBA UNICELLULAR AND MULTICELLULAR ANIMALS . . 22Q 



PRACTICAL DIRECTIONS 238 



CHAPTER II 



SPHJERELLA 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 



OPALINA : MONOCYSTIS -PARASITISM BIOGENESIS AND 



ABIOGENESIS CLASSIFICATION OF THE UNICELLULAR 



ORGANISMS EXAMINED 280 



PRACTICAL DIRECTIONS 293 



J 



CHAPTER V 



HYDRA : OBELIA -SYMBIOSIS -ALTERNATION OF GENERA- 

 TIONS -CHARACTERS OF THE PHYLUM CCELENTERATA . 294 



PRACTICAL DIRECTIONS 322 



CHAPTER VI 



THE EARTHWORM : NEREIS CHARACTERS OF THE PHYLUM 



ANNULATA 326 



PRACTICAL DIRECTIONS 354 



CHAPTER VII 



THE CRAYFISH CHARACTERS OF THE PHYLUM AkTHROPODA 360 



PRACTICAL DIRECTIONS 386 



