Mitosis in Giardia muris (Grassi), X 2720, from culture mice unless 

 otherwise stated. 



Fig. 16. Late prophase. Blepharoplasts, axostyle, and posterior flagella 

 divided, chromatin in four masses, posterior peristome faded out, cytoplasm 

 abnormal, anterior halo displaced. 



Fig. 17. Dorsal view of later stage, axostvles diverging, duplex nature 

 chromatin masses indicated. 



Fig. 18. Metaphase, intranuclear spindle (shrunken?) without distinct 

 chromosomes, nuclear membrane and peristome heavily chromatic. From 

 Peromyscus. 



Fig. 19. Dorsal view of a similar stage. 



Fig. 20. The same stage, with heavy chromatic masses at poles of spindle. 



Fig. 21. Dorsal view of the same stage, spindle not shrunken, chromosomes 

 emerging. 



Fig. 22. The same stage as figure 20, with heavy polar masses. 



Fig. 23. Later metaphase, four chromosomes elongating and constricting in 

 the middle. 



Fig. 24. Close of metaphase, chromosomes parted in the right nucleus, part- 

 ing in the left. 



Fig. 25. Dorsal view of anaphase, chromosomes moving to poles of spindle. 



Fig. 26. Chromatin masses irregularly placed on the spindle, apparently 

 splitting parallel with spindle fibers. From Peromyscus. 



Fig. 27. Ventral view of late anaphase, chromosomes regularly grouped in 

 two sets at about equivalent levels. 



Fig. 28. Dorsal view of anaphase, chromosomes irregular in distribution, 

 two sets of parabasal bodies present (divided?). 



Fig. 29. Late anaphase, constriction of nuclear membrane to form daughter 

 nuclei. 



Fig. 30. Division completed in Giardia microti Kofoid and Christiansen. 

 Posterior peristomes detached, enlarged, parabasals massed below axostyle, large 

 chromatic masses in posterior half. 



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