262 THE BEGINNINGS OF IIFE. 



recognized characteristic of Infusoria, concerning which 

 we shall have more to say hereafter. 



It will, of course, be seen that the phenomena which 

 we have described as taking place in the ^proligerous 

 pellicle' may be watched by all who are conversant 

 with such methods of investigation. We do not require 

 to call in the aid of the chemist, we need exercise no 

 special precautions j the changes in the pellicle are of 

 such a kind that they can be readily appreciated by any 

 skilled microscopist. 



Just as we have supposed that living matter itself 

 comes into being by virtue of combinations and re- 

 arrangements taking place amongst invisible colloidal 

 molecules, so now does the study of the changes in the 

 'pellicle' absolutely demonstrate the fact that the 

 visible, new-born units of living matter behave in the 

 manner which we have attributed to the invisible 

 colloidal molecules. The living units combine, they 

 undergo molecular rearrangements, and the result of 

 such a process of Heterogenetic Biocrasis is the appear- 

 ance of larger and more complex organisms j just as the 

 result of the combination and rearrangement between 

 the colloidal molecules was the appearance of primordial 

 aggregates of living matter. Living matter is formed, 

 therefore, after a process which is essentially similar to 

 the mode by which higher organisms are derived from 

 lower organisms in the pellicle on an organic infusion. 

 All the steps in the latter process can be watched ; it is 



