VENATION AND SENESCENCE OF POLYEMBRYONIC CITRUS PLANTS 329 
primarily concerned with priority of development of the embryos, and not 
directly correlated with sexuality. 
10. Rejuvenation seems to be effected equally well through apogamous 
and through gametic reproduction. 
The writer wishes to express his indebtedness to Professor Lewis Knudson 
for valuable suggestions, and for placing at his disposal the Citrus seedlings 
with which this study was made. He also acknowledges the helpful 
suggestions of Dr. L. W. Sharp. 
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