PLATE 3^ 

 Bacterium viiians the cause of the South Carolina lettuce disease: 



A. — Cross-sections of a lettuce stem at two levels 35 days after inoculation with the 

 South Carolina yellow organism. The tissues are browned. 



B. — A longitudinal section of another plant inoculated at the same time as A. 



C. — A longitudinal section of a healthy stem for comparison. 



D. — Longitudinal sections at the crown of a lettuce plant one month after inocula- 

 tion, showing browning of the tissues. 



E. — A cross section at the crown of a lettuce plant one month after inoculation^ 

 showing browning of the tissues. 



