NUCLEAR DIVISION 



27 



of enabling us to watch the changes in the distribution of the 

 lines under changing conditions or continued strain. 



The chromosomes are now completely split, each into its two 

 daughter-segments, which glide apart (Fig. 7, G-, ep), and pass 

 each to its own pole of the spindle, stopping just short of the 



Fio 7 —Completion of mitotic cell-division. Q, splitting of equatorial plate [ep) ; H, 

 recession of daughter chromosomes ; I, J, reconstitution of these into new nuclei, 

 fission of the centrioles and of the cytoplasm, if, Central fibres of spindle ; n, 

 remains of old nucleole. (From Wilson.) 



centrosome (I). Thus, on the inner side of either centrosome is 

 found an aggregation of daughter -segments, each of which is 

 sister to one at the opposite pole, while the number at either 

 pole is identical with that of the segments into which the old 

 nucleus had resolved itself at the outset. The daughter-segments 

 shorten and thicken greatly as they diverge to the poles, and on 

 their arrival crowd close together. 



A distinct wall now forms around the aggregated daughter- 



