INOCULATION OF GELATINE AND AGAR. 53 



ally applicable to the culture of tubercle bacilli. The glycerine 

 agar has now superseded it. 



Human blood serum derived from placenta, serum from ascitic 

 fluid, and ovarian cysts are prepared in a similar manner to the 

 above. 



Other Nutrient Media. Milk, urine, decoctions of various 

 fruits and plants, and lately for cultivating anaerobic bacteria, 

 eggs. 



Fresh Egg Cultures, after Hiippe. The eggs in the shell are 

 carefully cleaned, washed with sublimate, and dried with cotton. 



The inoculation occurs through a very fine opening made in 

 the shell with a hot platinum needle ; after inoculation, the 

 opening is covered with a piece of sterilized paper, and collodion 

 over this. 



CHAPTER X. 



INOCULATION OF GELATINE AND AGAR. 



Glass Slide Cultures. Formerly the gelatine was poured on 

 little glass slides such as are used for microscopical purposes, 

 and after it had become hard, inoculated in separate spots as 

 with potatoes. 



Test Tube Cultures. The gelatine, agar, or blood serum having 

 solidified in an oblique position, is smeared on the surface with 

 the material and the growth occurs, or the medium is punctured 

 with a stab of the platinum rod containing the material. The 

 first is called a stroke or smear culture, the second a stab or thrust 

 culture. In removing the cotton plugs from the sterile tubes to 

 carry out the inoculation, the plugs should remain between the 

 fingers in such a way that the part which comes in contact with 

 the mouth of the tube will not touch anything. 



After the needle has been withdrawn the plugs c^re re-inserted 

 and the tubes labelled with the kind and date of culture. 



Plate Cultures. Several tubes of the culture medium are 

 made liquid by heating in water bath, and then inoculated with 

 the material as follows : 



