76 FertiJit}/ in Cichorium intybus 



it is, the comparison may be based on the proportion of self-fertile 

 plants and their fertilities, as has been done above. 



2. Performance of families descended from crosses between the wild 

 white-flowered plant A and plant EM of Barbe de Capucin. 



By fer the greater number of plants of the cultures were derived 

 from crosses between the two plants A and E'22. Among the 75 i^i 

 progeny of the reciprocal crosses between these two self-sterile plants, 

 there were 8 plants self-fertile to some degree. Progenies of three of 

 these plants constituting three families, {A x E22)-4.-, {A x E22)-9-, 

 and {E22 x A)-10-, have now been grown for three further genera- 

 tions. With the one exception of series {E32 x A)-10- Ser. II. 10- all 

 the diiferent series of these families grown in 1916 had three generations 

 of self-fertile parentage. The data for these various series will now be 

 presented together with a discussion of the results obtained for these 

 (sub) families. 



(a) The family {A x E23)-4.-. 



Data for the three series of this family grown in 1916 are presented 

 in Table II, and a summary of all the series of the family is given in 

 Table VII. 



Of the series (A x E33)-4--3-6- only two plants were grown. These 

 were both self-sterile. The fertilities of the parental line of descent 

 were respectively 4, 13, and 5. 



The series (A x E33)-4.-3-ll- compri.sed 29 plants, of which 20 were 

 self-sterile and 9 self-fertile. Not only was the proportion of self-fertile 

 plants low, but the fertilities of such plants were low, ranging from 

 1 to 26°/^ with the average at 8°/^. For this series the immediate 

 parent was of rather high fertility (32 °/J, but the ancestry previous to 

 this was of 4 and 13 7o- The feeble self- fertility of the series as a whole 

 and of the various individuals comprising it is most noticeable, especially 

 in comparison with the behaviour of such a series as (Eo x A)-4-4- 

 reported in Table I. 



Of the 16 plants of series (A x E23)-4--0-3-, eight were self-fertile 

 with range from 2 to 62 °/,_^,and with an average of 25 °/^. The relative 

 number of self-fertile plants, the range of fertilities, and the average 

 fertility are all higher for this series than for (A x E33)~4-3-ll-. 



A consideration of the family history shows that there has been no 

 parent in this family with a fertility higher than 32 '/o- The fertility 



