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INTRODUCTION TO CYTOLOGY 





Fig. 59. — Mitosis in the spermatocyte of Salamandra. 



I, prophase, centrosomes in astrosphere substance; latter spread out on nucleus. 77, 

 prophase; bivalent chromosomes formed; centrosomes beginning to diverge; central spin- 

 dle and asters developed. Ill, late prophase: nuclear membrane dissolved; spindle 

 fibers attaching to chromosomes, centrosomes moving apart. IV, anaphase: connecting 

 fibers prominent. V, telophase: constriction of cell nearly complete; mid-body forming 

 on central spindle or interzonal fibers. (After Meves, 1907.) 



)()(). 



