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MANUAL OF AMERICAN GRAPE-GROWING 



feet hermaphrodites, while in the other kind the stamens are 

 smaller and shorter than the pistil and eventually bent down 

 and curved under. The two kinds of stamens are shown in 

 Figs. 53 and 54. These may be called imperfect hermaphro- 

 dites since they are seldom as fruitful as the perfect hermaph- 

 rodites unless fertilized from another plant. Examined with 



Fig. 54. 



Grape flowers. Left, upright stamens of Delaware ; right, de- 

 pressed stamens of Brighton. 



a microscope, it is found that self-sterile plants usually bear 

 abortive pollen and that the percentage of abortive pollen 

 grains varies greatly in different varieties. The upright or 

 depressed stamen does not always indicate the condition of the 

 pollen, since there are many instances in which upright stamens 

 bear impotent pollen and occasionally the depressed stamens 

 bear perfect pollen. 



The leaf. 



Blade: The expanded portion of the leaf. 



Lobe: The more or less rounded division of the leaf. 



Sinus: The recess or bay between two lobes. 



