THE VITAL PHENOMENA OF THE CELL 



197 



centrosomes with their radiation spheres situated at either end of 

 the spindle. 









-P 



Fig. 93. Fritillaria imperiulis. A resting nucleus and other nuclei at various stages of* 

 division, taken from the iree protoplasmic lining of the wall of the embryo-sac depicted in 

 Fig. 128 (after Strasburger, Practical Botany, Fig. 191). A A resting nucleus; B a coil of 

 thick threads, as yet unsegmented ; C a portion of a nuclear thread, more highly magni- 

 fied ; I) a nuclear spindle, with segments longitudinally split ; E the separation and change 

 of position of the daughter-segments. A, B, D, E x 800 ; C x 1100. 



When the process of division has reached its highest point, the 

 nuclear segments split longitudinally. The daughter segments 

 then travel towards the two poles, twenty-four on each side (-E"), 

 and thus form the foundation for the daughter nuclei, which 

 develop in a manner similar to that described as occurring in 

 Salamandra maculata. As soon as the daughter nuclei become 

 vesicular, several nucleoli appear in them. 



Up to this point the resemblance shown by the process to that 

 seen in animal nuclear division has been complete; however, now, 

 at the end of the whole process, a peculiar and interesting devia- 



