EXPLANATION OF PLATE 9 



All figures were drawn by camera from preparations fixed in hot Sehaudinn 's 

 fluid and stained with iron haematoxylin. 



Binary fission in Uexamitiis ovatus, sp. nov. from Diemyctylus torosus. 

 X 2583. 



Fig. 1. Trophozoite showing six anterior and two posterior flagella, ble- 

 pharoplast, nuclei and axostyles. 



Fig. 2. The same, axostyles twisted. 



Fig. 3. Prophase of division, showing splitting of the axostyles. 



Fig. 4. Prophase of division: blepharoplasts and motor apparatus occupying 

 polar positions in relation to the nuclei, connected by paradesmoses. 



Fig. 5. Prophase of division with the karyosome breaking up into granules. 



Fig. 6. Prophase with spireme formation. 



Fig. 7. Prophase with ehoromosomes emerging from spireme (?). 



Fig. 8. Metaphase of division, two chromosomes visible in upper nucleus. 



Fig. 9. Early anaphase of division, chromosomes moving towards poles. 



Fig. 10. Early telophase: beginning of formation of new nuclear membranes, 

 chromosomes visible. 



Fig. 11. The same: old nuclear membrane beginning to fade. 



Fig. 12. The same stage. Chromosomes distinct. 



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