Fig. 259. Mitosis. A, resting cell with nucleus and true nucleolus; r, attraction 

 sphere with two centrosomes. 5, early prophase. Spireme formed; nucleolus still 

 present; two centrosomes connected by fibers of achromatic spindle to form amphiaster. 

 C, later prophase. Spireme segmented to form chromosomes; achromatic spindle; 

 polar rays; nuclear membrane fading. D, end of prophase. Monaster, with mitotic 

 figure complete; chromosomes aggregated at equator of nucleus; centrosomes connected 

 by fibrils of achromatic spindle. £, metaphase. Longitudinal cleavage; splitting of 

 chromosomes to form daughter chromosomes, ep; n, cast-off nucleolus. F, anaphase. 

 Daughter chromosomes passing along fibrils of achromatic spindle toward centrosomes; 

 division of centrosomes; if, interzonal fibres or central spindle. G, late anaphase. 

 Formation of diaster; beginning division of cell body. H, telophase. Reappearance 

 of nuclear membrane and nucleolus; two complete daughter cells, each containing a 

 resting nucleus. (From Wilson, The Cell. Courtesy of The Macmillan Co.) 



