LIST OF ILLUSTRATIONS. 



VII 



Page. 



FIG. 64. Wound Reaction (third day)in Pricked 



Potato-leaf, plant No. 61 239 



65. Leaf of Cucumber Plant No. 9 1, show- 



ing Pricked and Wilted Area (the 

 shaded part) 242 



66. Progress of Wilt in 8 days on Inocu- 



lated Leaf of plant No. 113 247 



67. Cross-section of Inoculated Plant No. 



149 at extreme top of stem, showing 

 Infection of all the bundles 250 



68. Lamina of Squash-leaf (in section), 



showing the Bacteria confined to 

 the bundle although Wilt involved 

 the Parenchyma 251 



69. Infected Bundle of Inoculated Musk- 



melon No. 150 252 



70. Sketch of Swollen Bacteria from the 



Interior of Vine No. 199 256 



71. Wilt of Inoculated Winter Squash at 



end of 9 days, plant No. 215 258 



72. Progress of Wilt in Inoculated Squash 



leaf on plant No. 216 259 



73. Inoculated Squash-leaf on plant No. 



223 261 



74. Progress of Wilt on Leaf of Inoculated 



Plant No. 245 265 



75. Wilt on Leaves of Cucumis melo, var. 



dudaim, plants 276, 277 269 



76. Wilt on Inoculated Leaf of Cucurbita 



californica, plant No. 280 269 



77. Cross-section of Petiole of Inoculated 



Leaf of Cucurbita foetidissima 

 (Plant 273), showing Bacteria con- 

 fined to the Vascular Bundles 272 



78. Detail from Vascular Bundle of Cucur- 



bita foetidissima occupied by B. 

 tracheiphilus 273 



79. Single Spiral Vessel of Cucumber Stem 



in cross-section, showing Lumen 

 plugged by B. Iracheiphilus 285 



80. Cross-section of Petiole of an Inocu- 



lated Squash-leaf 12 bundles oc- 

 cupied by B. tracheiphilus 286 



81. Cross-section of a Squash Bundle 



destroyed by B. Iracheiphilus. It 

 also shows occupation of surround- 

 ing parenchyma 287 



82. Camera drawing of unstained B. 



tracheiphilus from stem of a Wilted 

 Cucumber from the field (1893) .... 288 



83. Sketches of dividing rods of B. 



tracheiphilus after staining with 

 nitrate of silver 288 



84. Flagellate rods of B. tracheiphilus, 



capsule also stained 288 



85. Gelatin-stab cultures of B. trachei- 



philus 288 



86. Gelatin-streak culture of B. trach- 



eiphilus 290 



87. Petri Dish Agar Poured-plate of B. 



tracheiphilus at end of 6 days 291 



Page. 



FIG. 88. Small portion of Agar Poured-plate at 



end of 7 days in thermostat 291 



89, 90. Enlarged Colonies of B. trachei- 

 philus 291 



91. Streak Cultures of B. tracheiphilus, 



showing discrete growth 292 



92 . Behavior of B. tracheiphilus in Fermen- 



tation-tubes 293 



93. Simple apparatus used for Testing 



Growth in Hydrogen 294 



94. Restricted growth of B. tracheiphilus 



on a Slant Agar Streak buried under 

 more agar 295 



95. Restricted growth of B. tracheiphilus 



in Acetic Acid Agar 295 



96 Crystals in old Litmus-milk Cul- 

 tures of B. tracheiphilus 296 



97. Germicidal Action of Sunlight on B. 



tracheiphilus 297 



98. Cabbage-leaf showing upward move- 



ment of Brown Venation due to 

 Bact. campestre 301 



99. Dwarfing and Loss of Leaves in 



Cauliflower attacked by Bact. cam- 

 pestre 302 



100. Head of Cabbage showing Blackened 



Vascular Ring due to Bact. cam- 

 pestre 303 



101. Cauliflower Stem from Texas, show- 



ing Blackened Vascular Ring due 



to Bact. campestre 303 



102. Cross-section of Petiole of Cabbage, 



all the bundles of which are black- 

 ened by Bact. campestre 304 



103. Cauliflower Stems from Florida, show- 



ing disease further advanced, i. e., 

 cavities in the pith 305 



104. Cross-sections of Kohlrabi showing 



Blackened Vascular Bundles in 

 White Flesh 306 



105. Stem of Collards attacked by Bact. 



campestre 307 



106. Turnip-root hollowed out by Bact. 



campestre 38 



107. Cavity in fleshy part of Kohlrabi due 



to Bact. campestre 39 



108. Cabbage-leaf showing wedge-shaped 



area of Bacterial Infection (Black 

 Venation) attributed to insect 

 Gnawings 3 IO 



109. Cross-section of Cauliflower Petiole 



showing tissues occupied by Bact. 



campestre 3 11 



no. A detail from fig. 109 3 12 



in. Cross-section of Turnip-root showing 



two vessels, one fully occupied by 



Bact. campestre 3'3 



112. Longitudinal section of Turnip-root 



showing bacteria in a vessel 314 



113, 114. Bacterium campestre occupying 



Intercellular Spaces 315. 3'6 



