FIG. 30. CABBAGE DISEASES. 



a. Club root (after Cunningham), b. cell filled with spores of the club root or- 

 ganism, c. spores and swarm spores of Plasmodiophora brassica (b. and c. after 

 Chuff), d. black rot of cabbage (after F. C. Stewart), e. individual black rot germs of 

 Pseudomonas campestris, /. black-leg on young cabbage seedling, g. black-leg lesion 

 on foot of older cabbage plant, h. black-leg lesion on cabbage leaf, i. pycnidium of 

 Phoma oleracecE, j. pycnospores of P. oleracece (i. and.;', after Manns). 



