ISOLATION OF B. TYPHOSUS FROM FECES 



365 



typhoid. Obviously, it is only with this class of material that 

 the method, if of value, will aid in diagnosis. In order to deter- 

 mine more accurately the initial number of typhoid bacilli, we 

 incorporated the use of the brilliant green medium described by 

 Krumwiede, Pratt and McWilliams (1916), which has proved 

 extremely successful in the isolation of typhoid bacilli from feces. 

 As preliminary tests had shown that in stools as well as in broth 

 cultures, the typhoid bacilli were more or less rapidly lost on 

 standing after the shaking was over, we plated immediately 

 after shaking ten minutes with pentane, and obtained the follow- 

 ing results. 



These results indicate that the method with very short expos- 

 ure has some value as compared with the direct plating on a 

 non-restraining medium (Endo) alone. The general tendency to 

 reduction in the number of typhoid bacilli, not necessarily 

 associated with a markedly greater decrease in the fecal flora, 

 was again observed in this series. On the whole, the data pre- 

 sented indicate that the method is not a reliable one for the 

 relative enrichment of typhoid bacilli in stools. Compared 

 with direct plating on a differential medium (brilliant green agar) 

 the method is evidently inferior. 



A report by Schuscha (1916) recently available only in an 

 abstract indicates that his results with the method have not 

 been more satisfactory than with direct plating. 



We might add that the method of pentane shaking is unsuited 

 to routine laboratory work. The pentane itself is highly inflam- 



