VI LIST OF ILLUSTRATIONS. 



TEXT FIGURES. 



Fig. Page, 



i . Oozing of Bad. vascularum from Cut Surface of Australian Sugar-cane 5 



2. Cobb's Figures of Bad. vascularum 6 



3. Cane-plants Dwarfed by Bad. vascularum 9 



4. Bacterial Cavity under Terminal Bud in Sugar-cane Attacked by Bad. vascularum 15 



5. Radial Longitudinal Section through Leaf-sheath of Sugar-cane No. 4, Attacked by Bad. vascularum . 15 



6. Detail from fig. 5, showing how the Bacteria reach the Surface through Stomata 16 



7. Cross-section of fig. 5, including two vascular bundles 17 



8. Inoculated Cane No. 9, showing Sidewise Pushing of the Terminal Bud 17 



9. Cane Stripped of Leaves to show Dwarfing and Twisting of Terminal Bud (zigzag growth) due to 



Bad. vascularum 18 



10. Pushing of Buds in Inoculated Purple Cane No. 38 18 



1 1 . Longitudinal Section Showing Pushing of Buds and Red Nodal Stain in Stem of Sugar-cane Attacked 



by Bad. vascularum 19 



12, 13. Microscopic Appearance of Reddened Vascular Bundles of Sugar-cane Attacked by Bad. vascularum. 19, 20 



14. Pure Culture of Bad. vascularum Plated in 1902 from Australian Cane 20 



15. Nanism of Inoculated Sugar-cane 22 



16. Leaf of Sugar-cane showing White Stripes due to Bad. vascularum 23 



17. A Pure Poured Plate Culture of Bacterium vascularum from inoculated Cane No. 9 25 



18. Contents of Red Slime from Interior of Sugar-cane 9 months after Inoculating with Bad. vascularum 45 

 19, 20. Cross-sections of Vascular Bundles of Sugar-cane, showing Parts Occupied by Cobb's Organism. 49,50 



2 1 . Early Stage in Occupation of a Bundle, Cane-plant No. 6 51 



22, 23. Longitudinal Sections through Inoculated Cane No. 6, showing Destruction of the Vascular Bundles. 52, 53 



24. Longitudinal Section through Inoculated and slightly Diseased Purple Cane No. 30, showing Red 



Bundles as Dark Lines 54 



25. Cross-section of Vascular Bundle of Sugar-cane Occupied by Bad. vascularum (the dark portions 



surrounding the yellow slime were a deep red color) 55 



26, 27. Bacteria (highly magnified) from Different Parts of Inoculated Cane-plant No. 6 55 



28, 29. Flagellate Rods of Bad. vascularum 55, 56 



30. Rods of Bad. vascularum from a Young Culture on Nutrient Agar 56 



31. A Pure Culture, Agar Poured Plate, of Bad. vascularum from Plant No. 11 57 



32. Streak Cultures of Bad. vascularum on Potato Agar 58 



33. Magnified Colony of Bad. vascularum on Glucose Gelatin 59 



34. Growth of Bad. vascularum on Cane-juice-gelatin with and without Peptone 59 



35. Tear-drop Formation of Bad. vascularum on Slant Gelatin with Cane-juice 60 



36. Streak Cultures of Bad. vascularum on Potato 60 



37. Bacterium vascularum in a Petri-dish Agar Poured-plate (one-half exposed to sunlight) 66 



38. Crystals from an Agar Streak Culture of Bad. vascularum 67 



39, 40, 41. Cross-sections of Maize Stems, showing Bad. stewarti Oozing from Vascular Bundles. Figs. 39, 40, 



from plants shown in pi. 6 (natural infections), fig. 41, from artificially infected plants... 91,92,95 



42. Radial Longitudinal Section through Basal Part of Stem of Diseased Sweet Corn from Long Island . . 98 



43, 44. Yellow Bacteria from Smear Preparations Made from Stems of Long Island Sweet Corn 98 



45, 46. Periphery of Portion of Corn-cob in Cross-section, showing Bacteria under and in Kernels .... 1 14. t 15 



47. Section through a very immature Corn Kernel and its Supporting Tissues (the area occupied by 



Bad. stewarii in the base of the Kernel is drawn in solid black 1 116 



48. A Detail from fig. 47, showing Bacterial Cavities and the Occlusion of Vessels 119 



49. Cross-section of the Infected Corn-husk shown in Vol. II, fig. 14, Inoculations of 1902 119 



50. A Detail from fig. 49, in the Vicinity of *, i. e., from another section in the series, showing stomatal 



Ooze of Bacteria 119 



51. Surface View of an Infected Corn-husk showing Bad. stewarti oozing from a Stoma. (For appear- 



ance in section of a similar stoma, see fig. 50) 120 



52. Longitudinal Tangential Section through a Diseased Corn-husk, showing Substomatic Chambers 



filled by Bad. stewarti 120 



53. Bacterially Spotted Husks, same as Vol. II, fig. 14, but from a Naturally Infected Plant, i. e., one 



grown in the hot-house in 1908 from diseased seed 121 



54. Occlusion of Single Spiral Vessel by Bad. stewarti on the Periphery of a Cob (longitudinal view). . 129 



55. Cross-section of Stem of Sweet Corn from Long Island, showing one Bundle with Occlusion of a 



Single Vessel by Bad. stewarti 129 



56. Section similar to fig. 55, but from Sweet Corn Inoculated by the Writer in Washington, in 1902, 



and showing entire Xylem Portion of the Bundle Occupied by the Bacteria (phloem free) 130 



57. Section through lower part of a Diseased Sweet Corn Kernel, showing Relation of Parts, etc 130 



