PLATE 16: 

 Bacterium tabacum: 



A. — Natural infection. Lesions are large and concentrically zonate. 



B. — Numerous confluent lesions on one side of the midrib have resulted in distortion 

 of the leaf. 



C. — Almost the entire leaf is involved and a portion of the rotted tissues have fallen 

 out. Natiu"al infection. 

 27810°— 18 5 



