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Plant-Breeding 



pistillate flowers are on entirely different plants, as in 

 willows and poplars, the plant is dioecious. The two kinds 

 of squash flowers are shown in Fig. 87. The pistillate 

 flower is on the left, and it is at once distinguished by the 

 ovary or little squash below the colored part, or corolla 

 of the flower. The lobed stigma is seen in the center. 

 The staminate flower is on the right. It has a longer 



FIG. 88. Flowers of clematis (Clematis virginiana). 



stem, no ovary, and the anthers are united into a con- 

 spicuous cone in the center. The flowers expand early 

 in the morning. Insects carry pollen to the pistillate 

 flower, which then begins to set its fruit, whilst the 

 staminate flower dies. The flower of the common wild 

 clematis is shown in Fig. 88. On the right are the 

 sterile flowers, which are wholly staminate. On the left, 

 the flowers with larger sepals the petals are absent 

 have a cone of pistils in the center, and a few short and 



