POLLEN 153 



Accordingly the Arabs plant only date-trees with 

 pistils, the only ones that will produce dates. But 

 when they are in flower, the Arabs go long distances 

 to fetch bunches of blossoms with stamens from 

 wild date trees in order to shake the pollen on the 

 trees they have planted. Without this precaution 

 there is no harvest. 



"But I am coming to an example that will be more 

 familiar to us. The pumpkin is monoecious : flowers 

 with stamens and flowers with pistils inhabit the 

 same house, the same vine. Before they are full- 

 blown they can easily be distinguished from each 

 other. The flowers with pistils have under the co- 

 rolla a large swelling which is the ovary, the future 

 pumpkin. The blossoms with stamens have not this 

 swelling. Well, from one pumpkin vine standing 

 apart in the garden let us cut off all the buds with 

 stamens before they open, and leave those with 

 pistils. For greater surety we will wrap each one 

 of these latter in a piece of gauze large enough to 

 let the flower develop without hindrance. This oper- 

 ation must be carried out before the buds open, in 

 order to make sure that the stigmas have not already 

 received any pollen. Under these conditions, not 

 being able to receive the vivifying dust, since the 

 flowers with stamens are cut off, and since also the 

 gauze wrappings keep out the insects that might 

 bring the pollen they had pilfered from some neigh- 

 boring pumpkin vine, the pistillate flowers will 

 wither after languishing awhile, and their ovaries 

 will dry up without growing into pumpkins. If, 



