THE BEGINNINGS OF LIFE. 



247 



in the production of Puramecia of a correspondingly 

 different bulk. Just as in the previously described 



Fig. 64. 



Mode of Origin of Paratnecia. ( X 8oo.) 



a. First stage of differentiation. 

 h. Later stage in which vacuole has appeared. 

 b' . Similar stage of much larger embryo. 



h". Another embryo which has segmented into four (only three parts 

 visible). 



c. Later stage — embryo filled with large particles and revolving within 



its cyst. 



d. Paramecium after it emerges from its cyst. 



e. Nassula-like form into which many afterwards passed. 



embryonal areas, masses of different size began to ex- 

 hibit signs of change ; so also here spherical portions of 

 the pellicle, differing within the limits above mentioned. 



