Ethel M. Doidge 



411 



Paine in connection with the "streak disease (l)," the cells become torn 

 asunder by shrinkage of dead cells and by the tension set up by growth 

 of the surrounding healthy tissue and eventually large cavities are 

 produced. There are not many living bacteria to be found in the dis- 

 organised tissues, but at the edges of such lesions, where the organism 



Fig. 2. Section through small lesion on fruit. 



is still active, large pockets of bacteria may be found. In the leaf the 

 organism penetrates through the thickness of the leaf, entirely dis- 

 organising the tissue, but it does not travel far in a lateral direction. 

 Stem lesions are very similar, but the organism has not been found to 

 penetrate beyond the cortex. 



27—2 



