240 THE BEGINNINGS OF LIFE. 



notions concerning credibility and the mode in which 

 living matter ought to conduct itself, rather than ade- 

 quately investigate the subject for themselves. 



According to Pouchet, the stages in the evolution of 

 Paramecium 'vlrtde were as follows : — The pellicle which 

 was at first uniform and evenly granular, after a short 



Fig. 63. 



Mode of Origin of Paramecia from the ' Pellicle,' after Pouchet. 

 (X 400.) 



time changed in aspect here and there, owing to a 

 concentration of its granules at tolerably equal dis- 

 tances into small more or less rounded aggregations 

 which soon became surrounded and defined by a clear 

 border, suggestive of a resemblance to the zona pel- 

 luc'ida of higher animals. The next change which took 



