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If the agar in the tube is less than one inch high, it 

 will be necessary to pour on top, after inoculation, the con- 

 tents of another agar tube, taking care to sterilize the 

 mouths of both tubes. Set aside the inoculated tubes in 

 the incubator for 24 to 48 hours. The cultures are then 

 examined in hanging-drop. Simple stains are made, also 

 double stains of spores. The drop or two of liquid which 

 sometimes accumulates on the surface of the agar, and 

 invariably on the bottom of the tubes can be stained for 

 ordinary nagella and for giant-whips. 



Make the following cultures at the same time as the 

 preceding : 



(1) Streak culture on inclined glycerine agar of the 

 tubercle bacillus, using either a pure culture, or a tubercle 

 from a guinea-pig inoculated with tuberculosis. Spread 

 the material thoroughly over the surface of the medium. 



(2) Streak culture on ordinary inclined agar of the 

 Achorion Schonleinii the fungus of favus. 



(3) Streak culture on ordinary inclined agar of Actin- 

 omyces the fungus of lumpy-jaw. 



After these three inoculations have been made the 

 cotton plug of each tube is cut off close to the mouth of 

 the tube, and this is then sealed either with a rubber cap, 

 or with sealing wax, or with paraffin of a high melting 

 point, 56 C. The sealed tubes are then placed in the 

 incubator for several weeks. 



STAINING OF FLAGELLA. 



In order to obtain good stains of nagella special care 

 must be given to the preparation of the cover-glasses. These 

 must contain as little organic matter as possible in order 

 to prevent the formation of a dirty precipitate on the 

 cover-glass. Excellent cover-glasses can be made by 

 dilution. A small loopful of the turbid fluid from the 

 bottom of the agar tube culture of (Edema bacillus No. II, 



