THE CELL 21 



appears, dividing the cell in two, and the division is accom- 

 plished (Fig. 3, 4). 



The network of the nucleus of actively dividing cells is 

 rich in nucleic acid, but in cells which have ceased to divide, 

 in which the nucleus has ceased to exercise its great repro- 

 ductive function, the amount of phosphorus i.e. of nucleic 

 acid diminishes, and may be actually less than the amount 

 in the cell protoplasm. 



Amitotic Division. In some cells the nucleus does not 

 appear to take an active part, the cell dividing without the 

 characteristic changes above discussed. 



