440 



XXXII. CELL-DIVISION AND NUCLEAR DIVISION. 



FIG. 154. Fritttlaria persica. Division of the pollen mother-cells, a, The coiled 

 condition ; ft, the nuclear segments, after longitudinal cleavage and folding, distributed 

 upon the unclear wall ; c, the nuclear spindle in profile ; d, the same as seen from one 

 of the poles ; e, division of the nuclear plate ; ./', separation of the sister chromosomes ; 

 /,. formation of daughter coils, and of the cell-plate ; A, opening out of the nuclear 

 threads in the daughter nuclei ; i, initiation of the nuclear plate ; k, complete condi- 

 tion of the same and of the nuclear spindle, on the right hand in profile, on the left in 

 polar view ; /, separation of the sister chromosomes into two segments, on the left in 

 profile, on the right as seen from the pole ; in, granddaughter coils, and formation of 

 the cell-plate ( x 800). 



