Xviii LIST OF ILLUSTRATIONS 



PAGE 



93. Tyrosin crystals in milk fermented by Bacterium campestre. 153 



94. Cross-section of a small cavity in a cauliflower stem, due to Bacterium 



campestre 154 



95. Cauliflower bundle in longitudinal section showing disorganization due 



to Bacterium campestre 154 



96. Turnip root in cross-section showing a bundle attacked by Bacterium 



campestre 155 



97. Beginning of a bacterial cavity in a turnip root. 156 



98. Single cell of turnip root showing Bacterium campestre, occupying the 



intercellular spaces 158 



99. Longitudinal section showing a vessel and cells of a turnip root occupied 



by Bacterium campestre 158 



100. Large sweet-corn plant destroyed in the field by Aplanobacler stewarti 



(EFS)McC.. 160 



101. Flint field-corn, showing white top due to Aplanobacter stewarti 162 



102. Aplanobacter stewarti oozing from cut bundles (cross-section) of a sweet- 



corn stem 163 



103. Aplanobacter stewarti oozing into water from vascular bundle of a 



sweet-corn stem longitudinal section 163 



104. Corn plant from Chula Vista, California, showing dwarfing, white top 



and suckering due to Aplanobacter stewarti 164 



105. Yellow spots on inner husk of sweet corn due to Aplanobacter stewarti. 164 



106. Cross-section of corn-husk from an inoculated plant showing bacterial 



masses in the tissues 165 



107. Stewart's disease of sweet corn, a detail of figure 106 . . 166 



108. Infected small bundle at extreme base of a corn kernel. Cross-section.. 167 



109. Cross-section of a larger bundle at the same level as figure 108. . 168 



110. Longitudinal section showing infected vessels, etc.. in periphery of a 



corn kernel, at the level of the radicle 169 



111. Infected vessels in periphery of sweet-corn kernel at the level of figure 



110. It shows Aplanobacter stewarti forming a small cavity. . . . 169 



112. Inoculated young sweet-corn plant attacked by Aplanobacter stewarti. . . 170 



113. Sweet-corn plant inoculated when young, and diseased when old. . 171 



114. A, B. Two types of surface colony in Aplanobacter stewarti 172 



115. Agar plate showing buried colonies of Aplanobacter stewarti and one 



coming to the surface. Also crystals 173 



116. Longitudinal section of two infected corn stems showing brown node 



and yellow striping 174 



117. Appearance under the microscope of cross-section of empty and infected 



(stained) bundles in a maize stem 174 



118. Single disorganized bundle of an infected maize stem, enlarged. Bac- 



terial mass stained deep red 175 



119. Potato attacked by Bacterium solanacearum EFS. From a field near 



Washington, D. C 177 



120. Early Rose potato inoculated with Bacterium solanacearum. Late 



stage 178 



121. Inoculated young tomato. Early stage. Leaves of inoculated shoot 



reflexed. . . .' 179 



122. A later stage of figure 121, showing incipient roots on inoculated stem . . 179 



