420 



F. M. Rolfs 



disorganized (Fig. 70). Radial rifts or pockets in the young wood and 

 cortex extend outward, often to the epidermis. As the twigs increase in 



Fig. 70. — Cross section of a young peach twig inoculated with a pure culture 

 of Bacterium Pruni obtained from a plum twig. Bacterial pockets are most 

 abundant in the cortical parenchyma. All cortical parenchyma cells in 

 the infected region arc distorted. The bacterial pockets in the cambium 

 region also arc to be noted. Occasionally the large ducts in the young 

 wood are filled with the organism 



size these rifts open and form an approximately longitudinal fissure. The 

 bacteria escape through these fissures in countless numbers as bacterial ooze. 



