stout: pollinations in CICHORIUM INTYBUS 397 



There appear to be no definite statements in the Hterature of 

 any steriHty in Cichorium Intybus. Fruwirth ('09) describes very 

 adequately the development of the flower parts in the processes 

 of opening and notes the adaptation for self- and cross-pollination. 

 He also records that he failed to obtain seed from branches that 

 he had enclosed for spontaneous self-pollination; in ten trials of 

 selfing he obtained no seed, but as the weather was rainy he does 

 not consider his tests conclusive. He suggests, in discussing 

 possible methods that may be used in hybridization, that if self- 

 pollinated flowers set no seed the act of castration might be 

 omitted in crossing and only precaution taken to prevent insects 

 from bringing pollen. It is this method that the writer has most 

 generally used in crossing onto a seed-parent known to be com- 

 pletely self-sterile. The Fi generations grown from crosses in- 

 volving plants A, C, Ej, and E22 and which are especially con- 

 cerned with this paper were from seed obtained by employing 

 the depollination method as described by Oliver ('10). 



OBSERVATIONS ON EFFICIENCY OF OPEN- 

 POLLINATION 



To test the efficiency of open-pollinations and to obtain evidence 

 on the efficacy of pollinations in successive days throughout the 

 season, observations were made in 19 14 on the flowers of a large 

 main branch on each of two plants. Each morning with the 

 exception of Sundays and days of heavy rain the flowers in each 

 head on the branches selected were counted and a tag was placed 

 about the base of the head recording the date of blooming and 

 the number of flowers. Later the seeds were counted and the 

 number also recorded. 



Data were thus taken on plant C from July 2 to August 24, 1914, 

 and these data are given in table 15. 



A total of 114 heads of plant C was observed (not including 

 seven heads which set seed but were completely shelled by birds), 

 comprising 2,304 flowers of which 1,402 set seed judged to contain 

 embryos. The percentage of flowers setting seed was 61. The 

 number of seed per head ranged from o to 21. In two instances 

 every flower in a head produced a seed. There were but five 

 heads that set no seed and these bloomed near the middle of the 

 season; three of these opened on the same day, July 14. 



