PLATE X 



Fig. I. — Natural Citrus canker infection on leaves of Citrus trifoliaia. 

 Fig. 2. — Mature cankers on fruit of Citrus decumana (courtesy of Dr. E. W. Berger). 

 Fig. 3. — Canker on seedling grapefruit leaves, entrance having been effected through 

 abrasions made by thorns. 



Fig. 4. — Yotmg spongy cankers on fruit of Citrus decumana. 



Fig. 5. — Phoma soda on cellulose agar showing dissolution of cellulose. 



Fig. 6. — Mature cankerous areas on leaves of Duncan grapefruit. 



