74 Heredity and Social Progress 



centre, and which divides when a new cell is 

 formed. At any rate, the first indication of 

 cell division is the appearance of two new 

 centrosomes about which the activity of each 

 part is concentrated, and, as they grow, the 

 cell is gradually divided until each part be- 

 comes independent. Two new centrosomes 

 now appear in each new cell and the process 

 of division is repeated. If consciousness is 

 evoked by the activity of these centrosomes 

 and two centres of alternate activity are 

 needed to sustain it, the process of cell 

 division must be delayed so that segments 

 instead of new cells may be formed. This is 

 done through improvements in the cell wall, 

 by which it becomes more elastic or stronger 

 and thus prevents the alternate activity at 

 the two centres from completely severing the 

 cell. If subsequent division likewise fails to 

 break through the original cell wall, the aggre- 

 gate of cells forms a multicellular organism. 

 The simplest of these aggregates involves a 

 bilateral growth in which are all the elements 

 of a continuous consciousness. Each of the 

 two original centres controls the activity of its 



