PLATE 43 



A. — Cross section of petiole of mature plant showing severe necrosis. All of the 

 outer phloem and part of the inner phloem groups are destroyed. The adjacent 

 cells of the cortex are also disorganized. X 130. 



B. — Cross section of nodal region of stem tip showing formation of large lysigenous 

 cavities extending from cortex to pith and involving inner phloem groups and meta- 

 sylem. X 130. 



