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Figure 13. Early prophase in vegetative cell of Arisaema showing chro- 
matin network. 
Figure 14. Continuous spireme. 
Figures 15 and 15a. Separation of chromatin ribbon into 16 chromosomes. 
The two figures show opposite surfaces of the same nucleus. 
Figures 16 and 17. Disappearance of nuclear membrane. Chromosomes 
grouped in nuclear plate, but not yet arranged on surface of spindle. Former 
view polar, latter lateral. 
Figures 18 and 18a. Mother star. Latter apparently multi-polar, due prob- 
ably to poor fixation. 
Figure 19. Metakinesis. 
Figure 20. Daughter star. 
Figures 21 and 21a and 22. Formation of cell plate. Second view (21a) 
from pole, with nuclei cut away. 
Figure 23. Completion of cell wall. 
