ILLUSTRATIONS. 



PLATES. 



Page. 



PLATE i. Frontispiece. 



(1) Ferdinand Cohn, founder of mod- 



ern systematic bacteriology. De- 

 ceased. 



(2) Robert Koch, founder of German 



school of bacteriology, director 

 of the Institute for Infectious 

 Diseases at Berlin. 



(3) Louis Pasteur, founder of French 



school of bacteriology. De- 

 ceased. 



(4) Dr. Roux, one of the leading spir- 



its of the Pasteur Institute. 



(5) Em. Duclaux, professor in the 



University of Paris and director 

 of the Pasteur Institute. De- 

 ceased. 



2. Bacterial Olive-knots produced on 



four plants by needle-pricks 10 



3. Cross-section of Petiole of Musk- 



melon, showing bundles disorgan- 

 ized by Bacillus tracheiphilus 12 



4. Datura metclloldes eight days after 



Inoculation with Bacterium solana- 

 cearum 16 



5. Zeiss Horizontal Photomicrographic 



Outfit 26 



6. Arnold Steam Sterilizer, Lauten- 



schlager Dry Oven, Hot Plate, and 

 Chamberland's Autoclave 48 



7. Hydrogen Generator and Wash Bot- 



tles in use 56 



8. Thermostat-room 74 



9. Chamberland Autoclave 84 



10. Engine for furnishing Vacuum and 



Compressed Air 94 



PLATE n. 

 12. 



13- 

 14- 

 15. 

 16. 

 17- 



18. 

 19. 



20. 

 21. 

 22. 

 23- 



24. 



25- 

 26. 



27. 

 28. 



29. 



30. 



TEXT FIGURES. 



Page. 



FIG. i. Cross-section of Sweet-corn Stem para- 

 sitized by Bacterium Stnvarti 4 



2. Cross-section of a Raw Carrot, showing 



wedging apart of Parenchyma Cells 



by Bacillus carotovorus 5 



3. A Detail from Fig. 2 6 



4. Turnip-root, showing Bacterium camfes- 



trc confined to vicinity of Vessels 7 



5. Bacterium campcstre. A small portion 



of Fig. 4 enlarged IO 



Page. 



Culture-room, i. e., place for making 



Cultures of Bacteria in Still Air loj 



Movable Hood of Wood and Glass, 

 under which Bacteriological Trans- 

 fers may be made 106 



The Reinhold-Giltay Microtome 120 



Distilled-water Apparatus 124 



Zeiss Stand lla 129 



Zeiss Photomicrographic Stand Ic.... 129 

 Mounted Camera for Enlarging, Re- 

 ducing, and Natural-size Work 134 



Lantern-slide Room 144 



Black Spot of the Plum 148 



Bacterial Disease of Broomcorn 150 



Bacterial Black Spot of Walnut 174 



Ditto, Late Stage 176 



Transmission of Wilt of Cucumber 



by Insects 178 



Brown Rot of Potato. Natural Infec- 

 tion of Tuber, Artificial Infection of 



Stems 202 



Brown Rot of Potato. Shoots wholly 



destroyed by inoculation 202 



Tomato-plant inoculated with Bac.- 



terium solanacearum 202 



Bacterial Wilt-disease of Tobacco 202 



Young Pear-shoots blighted by Bacil- 

 lus amylovorus 202 



Green Pear-fruits eight days after In- 

 oculation with Bacillus amylovorus. 202 

 Quince-shoots and Pear-fruits (cross- 

 section) showing Blight due to 



Bacillus amylovorus 202 



Small Green Apples blighted by Ba- 

 cillus amylovorus 202 



Page. 



FIG. 6. Turnip-root, showing Bundle occupied 

 by Bacterium camfestre and the com- 

 mencement of a cavity; a later stage 

 than Fig. 5 1 1 



7. Cauliflower-petiole, showing Bundle de- 



stroyed by Bacterium camfestre 12 



8. Melon-wilt due to Bacillus tracheiphilus. 13 



9. Cross-section of Bundle of a Cucumber- 



stem, showing Bacillus tracheiphilus 

 restricted to the Spiral Vessels and 

 Three pitted vessels 15 



