THE LIVING ORGANISM 219 



Diagram showing the Changes in the Nucleus when 

 a Cell Divides to form Two Cells. The first 

 sketch shows the resting condition with a reticular 

 nucleus, the next shows the nucleus matter forming 

 a skein. In the third figure the skein has divided 

 into pieces or chromosomes, the fourth figure shows 

 these arranged on the spindle and the two centres 

 or centrosomes. In the fifth figure the chromosomes 

 are splitting lengthwise, and in the sixth these have 

 travelled to the two poles. The remaining figures 

 show the inversion changes and the formation of the 

 two daughter cells. 



