MATERIALS OF HEREDITY 9 



arrange themselves about a spindle-shaped structure, and 

 each one splits lengthwise. The two halves then separate, 

 one set of halves moving in one direction, to form a group 



Figure 2. Diagram of certain successive stages in the division of 

 the chromosomes and of the cell (mitosis). Only three chromosomes 

 represented. In A the three have split lengthwise; B, C, D show suc- 

 cessive stages in the separation of the halves into the two new cells 

 produced. 



by itself, while the other halves move in the other direc- 

 tion and form another group. Then the cell divides into 

 two, and one group of halves remains in one of the two 

 cells, while the other group of halves remains in the other 



