THE INTERRELATIONSHIP OF THE NUMBER OF 

 STAMENS AND PISTILS IN THE FLOWERS 



OF FICARIA. 



J. ARTHUR HARRIS. 



I. INTRODUCTORY REMARKS. 



A survey of the rapidly increasing literature must convince 

 anyone that the problem of the factors which determine the sex 

 of the organism is one of such complexity that it cannot be 

 solved on the basis of any one kind of material or by any one 

 method of research. 



In the flowering plants the same individual may produce both 

 eggs and sperm. The relative numbers of egg and sperm pro- 

 ducing organs may vary from individual to individual, or from 

 flower to flower within the individual. 



It is reasonable to assume that definite genetic, rnorphogenetic 

 or physiological factors underlie these variations. Any success- 

 ful attempt to determine these factors and to measure their 

 influence is just as truly a contribution to the wide problem of 

 the physiology of sex as the more conventional breeding experi- 

 ments and studies on the morphology of the germ cells. 



The purpose of this paper is to point out certain hitherto 

 unrecognized relationships between the number of sporophylls 

 in the flower of the ranunculaceous genus Ficaria. 



Heretofore those who have investigated the problem of the 

 relationship between the number of stamens and pistils in the 

 flower have been content to merely determine the correlation 

 between the number of the two kinds of spore-bearing organs. 

 Positive correlations of this kind should arise as the resultant 

 of any sets of environmental factors which tend to increase both 

 the number of stamens and the number of pistils in certain of 

 the plants or individual flowers and to limit the number of both 

 of these organs in others. Morphogenetically and physiologically 

 it seems of far greater importance to inquire whether the relative 



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