Fig. 



26 



EXPLANATION OF DIAGRAMS. 



PLATE L 



A plant cell. a, Cytoplasm : b, nucleus : i . centrosomes 

 d, nucleolus ; e, linin. 



2-3. Alveolar Cytoplasm, after Wilson. 



4. Tissue Cells, with variously-shaped nuclei. 



5. Vegetative cell, with resting nucleus, a, chromatin threads ; 



b, nucleus of Spirogyra. 



6. Condensed nuclei in pollen mother-cells ot wheat. 1-3, nuclei, 



t, Tapetum ; a, Nucleus (Spirogyra). 



7. Transverse section of a young Anther, 1-4, Archesporial stage.'^. 



8. Sporogenous cells in Anther loculus, surrounded by tlie Tapetmn, /, 



9. Resting Nucleus in Pollen mother-cell. 



10. Spirem and net-knots in Pollen mother-cell nucleus, 



11. Double spirem. 



12. Pollen mother-cell in synapsis, a, nucleolus. 



13. Contraction after synapsis, shorter and thicker thread 



14. Linin strands, with single and double rows of chromomeres. 



15. Spirem. with end-to-end Chromosomes. 



16. Mitotic spindle of a mother-cell, a, sjiindle threads ; b, nuclear- 



plate of V-sl'sps'^l chromosomes. 

 I". Multipolar Spindle, a, outside Nucleoli. 



18. Anaphase: Movement of Chromosomes towards the poles. 



PLATE II. 



19. Telophase, a, Nucleoli. 



20. Successive division in Pollen mother-cells — Monocotyledon. 



21. Simultaneous division in Pollen mother-cells — Dicotyledon. 



22. Telophase : Chromosomes forming into Spirem of daughter-cells. 



a, cell-plate. 



23. Nuclear-plate of Homotype mitosis, a, nucleoli. 



24. Anaphase : Separated Chromosomes receding towards opposite poles. 



25-26 Late telophase : Vacuolisation of chromosomes in daughter-cells. 

 a, cell-plate : b, spindle fibrils. 



27. Spindle threads formed from linin, after Nichols. 



28. Vegetative-cell Nucleus in Anaphase mitosis. 



29. Cells showing later stages of division. 



30. Binucleate and Multinucleate cells showing Amitosis. 



31. Amitosis in Tapetum cells of Adoxa — surface view. 



32. Cells showing Centrosomes. a, resting nucleus ; b, metaphas-e 



spindle : c, daughter nuclei ; d. centrosomes. 



