Volume VII FEBRUARY, 1918 No. 2 



FERTILITY IN CIGHORIUM INTYBUS: SELF- 

 COMPATIBILITY AND SELF-INCOMPATIBILITY 

 AMONG THE OFFSPRING OF SELF-FERTILE 

 LINES OF DESCENT. 



By a. B. STOUT. 



(With Plates IV— VI.) 



CONTENTS. 



PACK 



Introduction 71 



Material, Methods, and Terminology 72 



Results of the Experimental Studies 73 



1. Performance of a family of Barbe de Capucin x wild white-flowered : 



the {&mi\y (E3xA)-4r- • . 73 



2. Performance of families descended from crosses between the wild white- 



flowered plant A and plant E22 of Barbe de Capucin ... 76 



(a) The family (A x E22)-4- 76 



(b) The family (A x E22)-9- 78 



(c) The family (E22 x A)-10- 83 



3. Fertilities in various Vegetative Types or Baces .... 88 



4. General Summary of Results ........ 89 



Discussion .............. 94 



Conclusions .............. 100 



Bibliography 102 



Introduction. 



The results presented in this paper pertain to the variation, the 

 heredity and the results of selection in respect to seed production in 

 progenies of self-fertile plants of chicory, such self-fertile plants having 

 first appeared sporadically among the descendants of self-sterile parents. 



It has already been noted (Stout, 1916, 1917) that the type of 

 sterility involved in my studies with chicory can best be ascribed to 

 a physiological incompatibility operating between sex organs that are 



Joom. of Gen. vii 6 



