farr: cytokinesis of pollen-mother-cells 317 



23. Anaphase of homoeotypic, spindles nearly at right angles, cytoplasm not shown. 



24. Earlj' telophase, cytoplasm granular, wall uniformly thickened. 



25. A little later, cell spherical, spindles appearing, peripheral cytoplasm not shown. 



26. Nuclei organized, cytoplasm fibrous, wall much thickened, surface only of upper 

 nucleus shown. 



27. First indication of cell-division, upper nucleus not shown in central section. 



28. Sides of mother-wall becoming concave, spindles distinct. 



29. Furrows deepen, nuclei draw away from the membrane. 



30. Spindle fibers straighten, and draw away from the center of the cell. 



31. Furrows become more abrupt. 



32. Projections of the mother-wall reach the center of the cell, all three nuclei shown 

 in central section. 



33. Tangential to two nuclei, showing the invagination of the cell-wall. 



34. Unequal narrowing of isthmuses. 



35. Furrows sharpen, and daughter cells begin to round up. 



36. Division complete at one isthmus, before the others. 



37. Spores distinct and imbedded in the thickened mother-wall, cytoplasm alveolar. 



