A. B. Stout 103 



All plants of this series were remarkably uniform in general habit of 

 growth and in flower colour. In all respects the plants seemed to con- 

 form closely to the characteristics of the original plants of N. Forgetiana. 



Series 3. These plants were grown from selfed seed of a green - 

 flowered plant which was highly self-compatible from the first day of 

 bloom. Of the 13 plants grown in the field, 12 were highly self-com- 

 patible in every flower tested during the first five days of bloom ; no 

 later tests were made. One plant was completely self-incompatible ; 

 it bloomed for 58 days, was tested on twenty dates with a total of 

 64 flowers including some of the very last to flower. 



Of 4 sister plants grown in the greenhouse, 3 were fully self-com- 

 patible and 1 was feebly self-compatible from the first day of bloom. 



This series was very uniform in general habit of growth and in flower 

 colour. The corollas were greenish white with the inner face becoming 

 white with age. 



Summary. The results show conclusively that there were plants 

 fully self-compatible or completely self-incompatible throughout the 

 entire period of bloom. The partially self-compatible plants were rather 

 irregular in production of pods to selfing. Many were partially self- 

 fertile from the first date of bloom and exhibited no decided change in 

 this relation thereafter ; in others the self-compatibility was most pro- 

 nounced or was confined to the earlier part of the period of bloom, to the 

 season of mid-bloom, or to the last part of the blooming period. The 

 cases of decided end-season self-fertility were few, and constituted a 

 small proportion of the partially self-compatible plants. 



Brassica pekitiensis. 



Experiments with this species have given results which show that 

 a few plants are highly self-fertile, but that the greater number are 

 self-incompatible. At least some of the self-compatible plants exhibit 

 several well defined stages or types of sterility in the succession of bloom : 

 (1) flowers blast or fail to develop; (2) flower parts develop and open 

 normally but abscission of pistil soon follows after self-pollination, or the 

 pistils remain attached for a longer time but fail to develop into pods ; 

 (3) a period of fruit and seed production ; (4) a period same as (2) ; and 

 (5) failure of flowers to open normally or even their blasting as in (1). 

 In self-incompatible plants the period of fruit and seed production to 

 selfing is omitted. In certain plants stage (1) is omitted. In one self- 

 fertile plant stage (5) was omitted in the main branches. The lateral 



7—2 



