PLATE 38 



A. — Cross section through upper part of stem, showing necrosis in outer phloem and 

 cortex. X 104. 



B. — Cross section through distal region of stem, showing formation of intercellular 

 spaces in outer phloem and cortex, x 400. 



C. — Cross section through distal region of stem, showing formation of intercellular 

 spaces between the cells of the inner phloem, x 800. 



D. — View of another phloem group showing cell wall thickening, x 320. 



