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EXPLANATION OF PLATE VI 



Each group of flowers is from the same raceme on the same date. Petals have been 

 removed. The scale in inches shows the reduction from natural size. 



Fig. 2. Three sister flowers uniform as to maleness but highly variable in femaleness. 



Fig. 3. The stamens of the four flowers vary as to length; one stamen in b and one 

 in c are aborted; all others are highly functional. Pistils are functional in a, b, and c, but 

 aborted in d. 



Fig. 4. Four flowers from same plant as those of figure 3, several days later. Pistils 

 vary as to length but all are functional. Stamens all excellent in a, two much aborted and 

 indehiscent in b, all indehiscent in c, and all much aborted and containing no pollen in d. 



Fig. 5. Pistils variable; in a, b, and c, fully functional; in d, e, and /, rather aborted. 

 Stamens highly variable in each flower irrespective of the condition of the pistil. 



Fig. 6. All stamens much aborted or rudimentary. Pistils somewhat undersized 

 but functional. 



Fig. 7. Abortion of stamens only, as at a, or of pistil, as at c and d, with a flower (b) 

 fully hermaphroditic; all in bloom at the same time on the same raceme. Illustrates well 

 the marked one-sided abortion of sex organs. 



