Journal OF The New York Botanical Garden 



Plate 290 



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Pollen of date palm 



Above. Sample of fresh 1923 pollen from a good male, showing good 

 germination on the agar-sugar medium (magnified about 90 times). When 

 such pollen germinates on the pistils of the date flowers, the tubes grow 

 down into the ovaries and function in the processes of fertilization, which 

 are necessary for the proper formation of fruit. 



Below. One-year-old pollen which failed to germinate in the tests. The 

 grains swelled to rotundity but no pollen tubes developed. 



