THE CAMBIUM AND ITS DERIVATIVE TISSUES 
433 
Fig. 13. Same. Anaphase from obliquely dividing fusiform initial, seen in tangential, 
longitudinal extension. X 850. 
Fig. 14. Same. "Resting" nucleus in ray initial. X 850. 
Fig. 15. Same. Metaphase in ray initial. X 850. 
Fig. 16. Same. Anaphase in ray initial. X 850. 
Plate XXVII 
Fig. 17. Pinus Strohus. Early telophase from longitudinally dividing fusiform 
initial, seen in radial, longitudinal extension. X 850. 
Fig. 18. Same.- Widening of central spindle and beginning of cell plate formation. 
Longitudinally dividing fusiform initial, seen in radial, longitudinal extension. X 850. 
Fig. 19. Same. Later stage than that shown in figure 18, showing disappearance of 
connecting fibers and movement of nuclei toward the cell plate. X 850. 
Fig. 20. Same. Later stage than that shown in figure 19, showing daughter nuclei, 
cell plate, and kinoplasmasomes. X 850. 
Fig. 21. Same. Later stage than that shown in figure 20, showing movement of 
kinoplasmasomes in opposite directions toward ends of protoplast and daughter nuclei 
in original positions at center of cell. X 400. 
Fig. 22. Same. Section of kinoplasmasome showing fibrillse and cell plate. X 2000. 
Fig. 23. Rohinia Pseudo-Acacia L. Fusiform initial in radial, longitudinal extension, 
showing cell plate, kinoplasmasomes, and daughter nuclei. X 850. 
Fig. 24. Same. Less advanced stage of cytokinesis. X 850. 
Fig. 25. Same. Beginning of cell plate formation. Note transverse position of polar 
axis of division figure. X 850. 
Fig. 26. Same. "Resting" nucleus of fusiform initial, seen in radial, longitudinal 
extension. X 850. 
Fig. 27. Pinus Strohus. Cytokinesis in obliquely dividing fusiform initial, seen in 
tangential, longitudinal extension. One daughter nucleus out of plane of section. X 850. 
Fig. 28. Same. Early telophase in transversely dividing fusiform initial, seen in 
tangential, longitudinal extension. X 850. 
Fig. 29. Same. Later phase than that of figure 28, showing extension of spindle 
and beginning of cell plate formation. X 850. 
Fig. 30. Same. Thickening of connecting fibers in equatorial region of spindle. 
Ray initial. X 850. 
Fig. 31. Same. Later stage than that shown in figure 30, showing cell plate. X 850. 
Fig. 32. Same. Later stage than that of figure 31, showing extension of cell plate 
and "drawing in" of fibers and nuclei. X 850. 
Figures 2, 3, 4, 5, 17, 18, 19, 20, and 21 of Plates XXVI and XXVII illustrate successive 
stages of karyokinesis and cytokinesis in a longitudinally dividing fusiform initial of a 
conifer (radial, longitudinal extension). Figures 15, 16, 30, 31, and 32 illustrate a similar 
series for a ray initial, and figures 26, 25, 24, and 23, a series for a short fusiform initial of 
a highly specialized type of dicotyledon, 
Plate XXVIII 
Fig. 33. Pinus Strohus. "Resting" nucleus from fusiform initial of root, showing 
shape during winter. Contrast figure 10. X 850. 
Fig. 34. Same. Nucleus from fusiform derivative cell which is in the earliest stages 
of differentiation into tracheary element. X 850. 
Fig. 35. Same. Later stage than that of figure 34. X 850. 
Fig. 35a. Same. Fusion of large nucleoli. X 850. 
Fig. 36. Same. Later stage than that shown in figure 35. X 850. 
Fig. 37. Same. Nucleus from young, differentiating sieve tube. X 850. 
Fig. 38. Same. Fragmentation of nucleus and nuclear vacuoles in derivative cells 
of cambium. X 450. 
