Plate 1. Above is mitosis in the pollen grains of Frjttillaria sp. Notice the polar view of 

 metaphase to the lower left, and the anaphase to the right, with an early telophase just 

 above it. Most of the other grains are in prophase stages. Below is meiosis in pollen 

 mother cells of Frittillaria sp. The nuclei are in diplotene and diakinesis stages and show 

 many unterminalized chiasmata. (Courtesy of C. D. Darlington.) 





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