70 The Third and Fourth Generation 



appears as a number of rodlike, ovoid, or other 

 characteristically shaped bodies now' known 

 as chromosomes. Meanwhile the boundary of 

 the nucleus has disappeared and the chromo- 

 somes have come to lie in one plane in the 

 mid-region of the more or less spherical cell, des- 

 ignated the equatorial region (Fig. 6, F). Now 

 each of the chromosomes divides into equivalent 

 parts. Not infrequently the division begins 

 before the component chromatin grains fuse, 

 and then it is apparent that each tiny granule 

 divides so that each daughter chromosome 

 receives one-half (Fig. 6, E). The daughter 

 chromosomes move toward the opposite poles 

 of the cell and fuse (Fig. 6, G and H). This 

 solid mass gradually becomes porous as the 

 meshwork reappears. New nuclear walls are 

 formed. Between the two new nuclei the cell 

 lays do^wn a new cell wall and what was one cell 

 has thus become two (Fig. 6, I). 



The whole process impresses one as a device 

 for insuring the equal distribution of the 

 chromatin materials to the daughter-cells. If 

 this chromatin is the real bearer of hereditary 



