80 



Suddoi Appcarcijicc and Constancy. 



grand i flora. B. bipinnata, and B. atro purpurea are well- 

 known species with ray florets. B. tripartita and B. 

 ccrnua arc very common in Holland and I have often 

 tried to find or to obtain examples with ligulate florets, 



Fig. 9. Senecio Jacohaca discoideiis, Koch. 



but as yet in vain. By this fact both forms are proved 

 to be constant as thoroughly as a proof can be. In other 

 countries, however, the z'arictates radiatac are known to 



