402 CELL INTELLIGENCE THE CAUSE OF EVOLUTION 



arcellae gregarinae, etc., are therefore of great interest, 

 because they show us the simple cell in a permanently 

 independent form. The human organism and that of 

 higher animals, on the contrary, is only one cell in its 

 earliest immature condition. As soon as the egg cell is 

 fertilized, it multiplies by division and forms a commun- 

 ity or colony of many social cells. These differentiate 

 themselves and by their specialization by various modi- 

 fications of these cells, the various tissues which com- 

 pose the various organs are developed. The developed 

 many-celled organisms of man and of all higher animals 

 resembles therefore, a social, civil community, the num- 

 erous single individuals of which are indeed developed in 

 various ways, but were originally only simple cells. * * * 



"We have reached the conclusion that the original, an- 

 cestral form of man, as of the other animals, was a one- 

 celled organism. The whole difficult problem of the His- 

 tory of Evolution is thus now reduced to the simple ques- 

 tion : How has the complex many celled organism arisen 

 from the simple one celled form? By what natural 

 process has the simple cell been transferred into the 

 complex life apparatus with all its various organs, the 

 apparently rational and purposive construction of which 

 we admire in the developed body? 



"Turning now to answer this question, we must bear 

 in mind the view to which we have already alluded, that 

 the many celled organism is ordered and constituted on 

 the same principle as a civilized state in which the sev- 

 eral citizens have devoted themselves to various services 

 directed towards common ends. This comparison is of 

 the greatest service in enabling us thoroughly to under- 

 stand the construction of man from many cells of various 

 kinds and to understand also the harmonious co-operation 

 of these various cells for an apparently preconceived 



