THE USE OF CULTURE MEDIA. 



57 



place the bouillon, gelatine, and agar media in the test-tubes 

 directly after filtration. The media can then be sterilised 

 in the test-tubes. 



In filling tubes, care must be taken to run the liquid 

 down the centre, so that none of it drops on the inside of 



FIG. 12. Apparatus which 



FIG. 13. Tubes of media. 



may be used for filling tubes. a- Ordinary upright tube. b. Sloped tube. 



cr. " Deep " tube for cultures of 



The apparatus explains itself. 

 The india-rubber stopper with 

 its tubes ought to be sterilised 

 before use. 



anaerobes. 



the upper part of the tube with which the cotton -wool 

 plug will be in contact, otherwise the latter will subsequently 

 stick to the glass and its removal will be difficult. The tubes 

 may, when filled, be placed in cages made of fine wire 

 gauze and sterilised. If all the contents of a flask of 

 medium be not filled into tubes, the remainder must be 



