FERMENTATION MEDIA 



81 



the acid beef -broth for which has been treated with the 

 colon bacillus (see p. 32), 1-2 per cent, peptone water, 

 or a medium which has been largely used by Houston, 

 Gordon and others, consisting of a 1 per cent, solution 

 of " Lemco " in distilled water with the addition of 



FIG. 11. Durham's 

 fermentation tube. 



FIG. 12. Einhorn's sacchari- 

 meter. 



peptone 1 per cent., sodium bicarbonate 0-1 per cent. ; 

 to either medium is added 1-2 per cent, of the fermentable 

 substance, and the mixture is tinged with litmus. If a 

 serum medium be necessary. Hiss's serum water (which 

 see) may be used. 



The fermentation tube has been much used of late for 

 the examination of faeces in abnormal intestinal conditions. 



M.B. 



