VI 



LIST OP ILLUSTRATIONS. 



Page. 



Fig. 15. Cross-section of Bean-leaf in an early 

 stage of Infection showing relation 

 of Bacterium phaseoli to the Tissues. 62 



16. Cross-sectioii of Leaf of Broom-corn 



showing an early stage of Stomatal 

 Infection 63 



17. Like Fig. 16, but the Bacteria have 



passed beyond the Substomatic 

 Chamber and are wedging apart 



neighboring cells 64 



i8. Angular Leaf-spot on Rivers Cotton 

 produced in hot-house by spraying 

 with water containing Bacterium 

 malvacearum 65 



19. Coconut Budrot: Sound enveloping 



Leaves removed to show Terminal 

 Bud attacked by the Soft Rot 67 



20. Coconut Budrot, showing inability of 



rotted bud to support its own 

 weight, when the outer leaf-sheaths 

 are removed 68 



21. Root-hairs of Bur-clover infected by 



Bact. leguminosarum 71 



22. Bacterial Strands in root-tubercle of 



Bur-clover 71 



23 . Olive Leaves with incipient Metastatic 



Tubercles due to Stem Inoculations. 72 



24. Secondary tumors in various places 



on leaf of Paris Daisy developing 

 from the internal tumor strand .... 73 



25. Solvent Action of Bacillus phytoph- 



thorus on middle lamellae of cells of 

 Potato tuber 76 



26. Aerial Roots on Daisy due to pres- 



ence of the Tumor farther up on 



stem 90 



2 7 . Swelling on Potato-shoot due to Inocu- 

 lation withnonvirulent Bact. solana- 

 cearum 91 



28. Sugar-beets Inoculated with Bact. 



tumefaciens (plated from tumor on 

 Paris Daisy) 92 



29. Sugar-beet Inoculated with Bact. 

 " tumefaciens (plated from Crown- 

 gall of Peach) 93 



30. Tyloses due to Bact. mori in the vessels 



of the Mulberry 94 



31. Bacterium leguminosarum: Effect of 



Bacterial Occupation on Cell- 

 nucleus in Soy-bean 97 



32. Effect of Root-Nodules on a Pea 



grown in confined air on Nitrogen- 

 free Soil 98 



33. Woronine's figures loi 



34. Bacterium leguminosarum: Cross-sec- 



tion of small Root-nodule of Soy- 

 bean showing tissue occupied by 

 the Bacteria 104 



35. Bacterium leguminosarum: Effect of 



repeated Freezings 105 



Page 



Fig. 36. Bacterium leguminosarum: Zoogloea: 

 threads growing through cells in 

 Root-nodule of Common Pea no 



37. Bacterium leguminosarum: Stages in 



formation of Y-shaped Bacteroids 

 from simple Rods 113 



38. Kefir grains. After Kern 156 



39. Disporacaucasica. After Kern 157 



40. Bacillus caucasicus. After von Freu- 



denreich 161 



41. Ma.rsha.WWaxA's Bacterium vermiforme 164 



42. Same, showing splitting of sheaths. . . 165 



43. The Ginger-beer Plant in a suitable 



Saccharine Medium 165 



44. The same, in an ordinary unsuitable 



medium (bouillon) 165 



45. Grains of "California beer-seed". .. . 166 



46. Section free-hand through one of the 



preceding, the darker bodies being 

 groups of Yeast imprisoned in 

 Masses of the Bacteria 167 



47. A bit of the preceding crushed out in 



water 167 



48. Another view showing oblong and 



round yeasts, contents omitted. . 167 



49. Spores in Yeast Cells taken from 



"Beer-seed" 167 



50. Hubbard Squashes Wilting from an 



attack of Bacillus tracheiphilus 210 



5 1 . Bacterial Ooze from vessels of Cucum- 



ber Stems 211 



52. Figure showing Viscidity of B trachei- 



philus 212 



53. Squash plant No. 215 dwarfed by 



B. tracheiphilus (upper figure) 213 



54. Cross-section of Cucumber-stem, show- 



ing location of Bacteria in a bundle . 214 

 55 Diabrotica vittata, distributor of the 



Bacillus of Cucumber- wilt 216 



56. Progress of wilt by hours on an Inocu- 



lated Leaf of Cucumber (plant No. 



2) 220 



57. Bacteria from Viscid Slime in plant 



No. 8 222 



58. Diagram of vine No. 15, attacked by 



Bacillus tracheiphilus 223 



59. Diagram showing distribution of 



Bacillus tracheiphilus in the Vascular 

 Bundle of a Cucumber Plant 8 days 

 after the first appearance of the wilt 

 (2 days after the appearance of sec- 

 ondary wilt, and 16 days after the 

 Inoculation) 225 



60. 61. Two stages of Wilt in Inoculated 



Leaf on plant No. 27 228, 229 



62. Cucumber from a field, showing in 



detail the Infection of a Single 

 Bundle of the stem by B. trachei- 

 philus 230 



63. Progress of Wilt on Inoculated Leaf 



of plant No. 28 (cucumber) 231 



