X 

 Fig. 10. 



i6. 



17. 



18. 



19. 

 20. 



2[. 



2,3. 

 -24. 



28. 

 29. 



30. 



3f. 

 Si- 

 Si- 



35- 

 36. 



37- 

 38. 



Datura mctelloides Inoculated hy Needle- 

 pricks with Bacterium solanaceariim. 

 The same plant as in Plate 4, but six 

 days later 17 



(a) Capsule of Organism plated from 

 Black Spot of Plum; ib) Viscid Cul- 

 ture-medium from which a was ob- 

 tained 18 



Yellow Ooze from Black Spot of Plum 

 stained by ordinary method 19 



Tenuous Threads of Bacillus trachciplii' 

 Ills drawn from a 'Musknielon Stem . . 19 



A detail from Fig. 13, highly magnified. 19 



Flagella stained from a pure culture of 

 a Bacterium grown in Water contain- 

 ing n few drops of I'schinsky Solution. 2r 



Beyerinck's Drop Bottle 21 



Double Blow Bulb 22 



Short Form of Bacterium campestre 

 when crowded 23 



Long Form of Bacterium campestre 

 when grown on Sugar-agar 2;^ 



Hanging-drop Culture 24 



Involution-forms of Bacillus trachciphi- 

 lus 24 



Y-shaped Forms from Root-tubercles of 

 Clover 24 



Zeiss Compensating Ocular, with Screw 

 or Filar Fye-piece Micrometer 25 



Zeiss Upright Photomicrographic Cam- 

 era 26 



Hand-lens for examining Bacterial Cul- 

 tures 



Hand-lens for examining Bacterial Cul- 

 tures, showing another form of mount 



Zeiss Cover-glass Measurer 



Nelson's Photographic Gelatin 30 



Agar-agar as received from Japan. 

 (Slender " Kanten ") 37 



Another form of Agar-agar made in 



Japan ( Square " Kanten ") 32 



32. Gclidiums furnishing Agar-agar... 33,34 



Agar-agar Flour as recci\ed from Euro- 

 pean Manufacturers 3:; 



Schleicher and Schidl's Folded Filter 

 Papers :jfi 



Thermo-regulator for Blood-serum Oven. 3; 



Iris-rhizome-rot (Organism grown on 

 Sterile Raw Carrot 41 



Tin-bo-\ in which Pipettes, Scalpels, etc., 

 may be sterilized 42 



Fluid Culture shnuing rise of Viscid 

 Precipitate when tw irlcd rapidly 42 



ILLUSTRATK IX.S. 



Page. Page. 



Fig. 39. Platinum-iridium Transfer Wires 43 



40. Simple way of filtering with Chamber- 

 land Bougie 44 



41. Roux Filter for separating Bacteria 

 from their Products 45 



42. Section of the Arnold Steam Sterilizer, 

 showing Principle of Action 46 



43. Lautenschliiger Centrifuge 47 



44. Wire-crate for holding Media to be ster- 

 ilized 48 



45. Oven for nse in solidifying Blood-serum, 

 etc., at Temperatures below 100° C... 49 



46. Simple Rack for holding Fermentation 

 tubes 52 



47,48,49, Ferraentaticn-tubes in actual use. . 53 



50. Ordinary Kipp Gas-generator 54 



51. Hempel's Burettes for Gas-analysis 55 



52. Hempel's Simple Pipette for Liquid Re- 

 agents 56 



53. Small Novy Jar 57 



54. Large Novy Jar; the most convenient 

 Form 58 



55. Simple Device for growing organisms in 

 Nitrogen 59 



56. Test for Reduction of Nitrates to Ni- 

 trites 63 



57. Crystals formed in Nutrient .^.gar as the 

 Result of Bacterial Growth 66 



Thick-walled Flask for Filtration or 

 Evaporation in vacuo 67 



Titration-deviees 68 



Sodium-hydrate Bottle 69 



Effect of Sunlight on Pear-blight Ba- 

 cillus 71 



Effect of Sunlight on Bean-spot Bacte- 

 rium 71 



Water-liath for Thermal Death-point 

 Experiments 76 



Roux Metal-bar Thermo-regidator 77 



Thermometer for Thermal Death-point 

 Experiments 79 



Leveling Apparatus 80 



Dewar Glass for Experiments with 

 Liquid Air 81 



Pctri-dish Poured Plate inoculated with 

 a measured quantity of a Bouillon 

 ■Culture of Bacillus tracheiphilus 82 



The same as Fig. 68, but poured after 

 Exposure to Liquid Air 83 



Stomat.al Infection by Bacterium pruiii 

 in Green Fruits 84 



Stomatal Infection by Bacterium pruiii 

 in Leaf 86 



Stomatal Infection by Bacterium pruui — 

 a Later Stage in Fruit ,^S 



59- 

 60. 

 61. 



63. 



64. 

 C'5- 



06. 

 (<7- 



(.18. 



69. 



71. 



