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Fig. 15.1 — Flower, pollen, stomata, pollen mother cells of diploid and tetraploid strains 

 of Phlox drummondii. A, B. Diploid and tetraploid flowers, respectively. C. Pollen mother 

 cell with 7 bivalents. D. Tetraploid pollen mother cell, n — 14. Note quadrivalency. E, 

 F. Stomata of diploid and tetraploid respectively. G, H. Pollen grains of diploid and 

 tetraploid, respectively. (After Eigsti and Taylor) 



