3i8 



BACTERIA IN RELATION TO PLANT DISEASES. 



The organism is wax-yellow, deeper or paler according to circumstances, changing to 

 a dirty yellow brown in the plant and in certain old cultures. The color on coconut flesh 

 standing in distilled water is approximately Ridgway's Naples yellow. On turnip cylinders 



Fig. 117 f 



*Fig. 1 16. Longitudinal section of a lurnip-root, showing how intercellular spaces are occupied and parenchyma 

 cells wedged apart by Bacterium campeslre. A later stage than fig. 1 14. Drawn from a photomicrograph, x 475. 



tl'ic;. 117. Bacterial cavity in interior of a turnip-root (plant No. 53), due to Bacterium campeslre, which was 

 inoculated by needle-pricks on blades of two leaves 52 days prior to fixing material. Exterior sound. Slide 115 I. 

 1 Irawn from a photomicrograph. 



{Fig. i i<S. Cross-section of a small turnip-root, showing bacterial pockets and wide distribution of organism 

 111 vascular system. Inked from a photomicrograph. In a cross-section of this root lower down the writer counted 

 [46 bundles occupied b\ masses of l lie bacteria and separated by unoccupied parenchyma. Surface of root unbroken. 



