stout: pollinations in cichorium intybus 395 



the self-pollinations of plants of this variety. In order to keep 

 the variety in pedigreed culture for a study of the heredity of 

 fasciation it was necessary to make numerous crosses to find fertile 

 combinations. In 191 5 crosses were also made with the wild 

 white- flowered plant A which has figured prominently in the 

 studies already reported. These data are compiled in table 14. 



In 191 4, 13 cross-pollinations were made, of which only 4 were 

 compatible. The work of this year involved 6 pairs of reciprocal 

 pollinations, four pairs (/ with 8), (j with 10), (j with 12), and 

 (q with 10) were sterile, one pair (7 with 2) were both fertile, 

 and one pair {6 with 8) gave different results as there was fertility 

 only when no. 8 was the seed-parent. 



In 191 5, thirty- two crosses were attempted between various of 

 the plants grown from the seed of the previous year. Fifteen of 

 these were fertile in some degree and in at least 6 crosses there was 

 rather high cross-fertility. No one plant was tested to a con- 

 siderable number of other plants either as a seed- or as a pollen- 

 parent. 



The results with this variety have a special bearing on the 

 general question of the influence of close relationship to fertility. 

 Twenty-four of the crosses were with plants of series 5, 19 15, as a 

 seed-parent. These plants were derived from the cross (8 X 2) 

 of the previous year. Of the 12 combinations with sister plants 

 as pollen-parents, 7 were sterile. Of 10 crosses with plants of 

 series i as pollen-parents, 7 were sterile. The 2 series had the 

 same grandparents but different immediate parentage. The 

 results of the crosses made show no marked differences between 

 crosses within a series or between different series. 



It is also to be noted that plants of this variety were not all 

 fertile with pollen of the wild plant yl as 3 of the 8 plants thus 

 crossed were unproductive of seed. Of two crosses with A as seed- 

 parent I was fertile. The two reciprocals that were made gave 

 different results, as especially noted in table 10. 



General summary of all cross-pollinations. — In tables 2, 9, 11, 

 12, 13, and 14, data are presented for crosses involving 125 different 

 plants. A total of 274 different combinations w^as attempted, of 

 which 159 were sterile and 115 were fertile in some degree. Gen- 

 eral cross-fertility on the whole seems less pronounced than is 

 cross-sterility. Table 2 is not fully representative of the results 



