PLATE 13. 



PAGE. 



Onagra BIENNIS. RacHum Culture No. 1 5a broad leaf . The stigma 

 was pollinated with unexposed pollen after the ovary had been 

 exposed for 24 hours to rays from radium bromide of 10,000 

 activity in a sealed glass tube 250 



Fig. a, flower-bud, with bract (lateral branch) ; b, petal ; C, nearly 

 mature capsule, with bract (main stem) ; d, flower (minus 

 corolla) ; e, leaf from main stem. 



