122 



BOTANICAL GAZETTE 



[FEBRUARY 



shriveled and not viable. Such plants were classed as feebly 

 self-compatible. Plants whose self-compatibility was classed as 



medium produced some viable 

 seeds. The number of pods, the 

 number of shriveled seeds, and 

 to some extent the number of 

 viable seeds varied greatly 

 among plants thus grouped. 

 The plants classed as strongly 

 self-compatible produced nu- 

 merous pods, and the total 

 number of viable seeds was 

 high. In these also the num- 

 ber of pods, their size, and the 

 numbers of viable and of shriv- 

 eled seeds varied greatly. The 

 various grades of self-compati- 

 bility were seen among sister 

 plants that were as nearly iden- 

 tical as is possible in regard to 

 vegetative vigor, number of 

 branches and flowers produced, 

 and as to calendar dates for 

 period of blooming. 



It was readily recognized 

 that the self-compatibility of 

 such plants was most strong 

 during the period of mid-bloom, 

 and that previous to and fol- 

 lowing this period there was 

 complete self-incompatibility. 

 A highly self-compatible plant 

 grown in isolation and carefully 

 self-pollinated from day to day 

 appeared at the end of the 

 fruiting period, as shown in figs. 6 and 7. Repeated tests by 

 crossings showed that in these, as in the case of the self-incompatible 



Fig. 7. — Plant of B. chinensis; no flower 

 abortion; plant highly self-compatible; 

 showing cycle of self-compatibility with 

 climax at time of mid-bloom. 



