178 Culture Media and Bacteria Cultivation 



using, as the culture medium must subsequently be sterilized 

 either by the intermittent method or in the autoclave after 

 the tubes are filled. The test-tubes and flasks into which 

 the culture medium is filled must, however, be previously 

 sterilized by dry heat, unless the subsequent sterilization 



Fig. 33. Funnel for filling tubes with culture media (Warren) : a, 

 Funnel containing the culture media in liquid condition ; b, pinch-cock 

 by which the flow of fluid into the test-tube is regulated; c, rubbei 

 tubing. 



is to be performed in the autoclave, when it may be un- 

 necessary. 



Sugar bouillon is bouillon containing in solution known 

 percentages of such sugars as glucose, lactose, saccharose, etc. 

 As Smith* has pointed out, if the quantity of sugar in the 

 bouillon is to be accurately known, it is necessary to first 

 destroy the muscle sugars in the meat-infusion by adding a 

 * "Jour, of Exp. Med.," n, No. 5, p. 546. 



