[From JOUKNAL OF GENETICS, Vol. mi. No. 2, February, 1918.] 



[All Ritjhts reserved] 



FERTILITY IN CICHORIUM INTYBUS: SELF- 

 COMPATIBILITY AND SELF-INCOMPATIBILITY 

 AMONG THE OFFSPRING OF SELF-FERTILE 

 LINES OF DESCENT. 



By A. B. STOUT. 



(With Plates IV— VI.) 

 CONTENTS. 



PAGE 



Introduction ............. '1 



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 family (£5 X. 4 H- • • 73 



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



flowered plant A and plant E-^2 of Barbe de Capucin ... 76 



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



(h) The family [A x Eii2)-9- 78 



(c) The family (E22 y. AyiO- 83 



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



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



Discussion ..........•••• 9* 



Conclusions ..........•••■ 1^*^ 



Bibliography ..........-.•• 1^"^ 



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 pliysiological incoiivpatihility operating between sex organs that are 



Journ. of Gen. vii 6 



