CAUSE OF HEREDITY 



273 



U,, 



FIG. 42. Diagram illustrating Mitosis or cell division. A, the cell commenc- 

 ing activity; B, C, D, phases in the formation of the spindle and the chromatin 

 loops or V's, also showing that the mother V's have split into daughter V's; 

 D, the chromatin loops forming the equatorial plate, chr; E, F, G, separation 

 of the daughter loops (daughter chromosomes) and their passage towards the 

 poles of the spindle, thus fori 



d their passage towards the 



ormng daughter nuclei; H, I, division of the 

 protoplasm so as to form two daughter cells; at, attraction sphere enclosing a 



entrosome; n m, nuclear membrane; chr.. 

 c w, cell wall; sp, spindle. SCHUTE. 



chromatin threads; p, protoplasm; 



that when the cell divides each half gets its full number 

 of individuals, skilled and otherwise. 



I quote from Walker : "What has been said with re- 

 gard to the selective mode of division, which insures that 

 an exactly representative half of each chromosome is 



