Figure 5. Fruits of Maryland Mammoth Tobacco. Left: Two normal truits 

 produced by pollination. Center: The ovary of a freshly opened flower. 

 Right: Two parthenocarpic fruits produced by injecting a solution of 0.2 per 

 cent potassium indoleacetate into the ovary through the pedicel. 



Figure 6. Crook-neck Summer Squash. At the extreme left is a normal 

 fruit. All the others were produced by cuttmg oif the apical end of the ovary 

 in the flower bud stage and smearing the cut surface with 5 per cent indole- 

 butyric acid in lanolin. The larger ones at bottom and right had more of 

 the ovary left and some o\ules. 



