Volume VII 



FEBRUAKY, 1918 



No. 2 



FERTILITY IN CICIIORIUM 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 



lutroduction ............. 71 



Material, Methods, and Termiuology 72 



Results of the Experimental Studies 73 



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



the iamWy (E3KA)-i- • . 73 



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



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



(«) The family (A x Ea2)-4- 76 



(b) The family (A x E'J2)-9~ 78 



(c) The family {ES2 x A)-10- 83 



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



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



Discussion . . . . . . . . . . . . . • . ^'^ 



Conclusions 100 



Bibliography .............. 102 



Introduction. 



The restilts 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 se.x organs that are 



Journ. of Gen. vii 6 



r<ew YORK 



