424 



BACTERIAL DISEASES OF PLANTS 



Fi,,. ;;_»:;. rmn,,i -,.1 iiuid of cidwn gall in Paris daisy. The result of a pure- 

 culture inoculation. Cross-section of stem between a primary stem-tumor 

 (caused by needle pricks introducing Bacterium tumefaciens) and a secondary 

 tumor in a leaf. It shows a tumor-strand in the inner wood and beyond it 

 normal wood (above) and normal i)ith (below). 



