THE BEGINNINGS OF LIFE. 



247 



in the production of Paramecia of a correspondingly 

 different bulk. Just as in the previously described 



FIG. 64. 

 Mode of Origin of Paramecia. ( X 800.) 



a. First stage of differentiation. 



b. Later stage in which vacuole has appeared. 

 b' '. Similar stage of much larger embryo. 



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

 visible). 



c. Later stage embryo rilled 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. 



