Daily Excretion of Bacteria in the Feces. 89 



26.89 P^'' cent. ; bacterial dry substance in moist feces, 7.0 per 

 cent. The average daily quantity of fecal dry substance and of 

 fecal nitrogen was calculated from the analysis of eight-day period 

 collections, and the average daily bacteria and bacterial nitrogen 

 calculated upon these quantities, regarding the bacterial content of 

 the dry substance of the single stool, upon which the bacteria were 

 determined, as representative of the feces for that period. Calcu- 

 lated in this way the greatest values found were 58 x 10'^ bacterial 

 cells per day by count, and 9.15 grams bacterial dry substance, 

 containing 1.006 grams nitrogen, per day by the gravimetric 

 method. The smallest values were 14 x 10^^ bacterial cells and 

 1.87 grams bacterial dry substance, containing 0.194 gram nitro- 

 gen per day. The average of all examinations was 32 x 10'^ 

 bacterial cells, and 5.34 grams bacterial dry substance, containing 

 0.585 grams of nitrogen, per day. 



There was considerable individual variation among the different 

 subjects of the group. For example, the average of all examina- 

 tions of Subject H was 40 x lo'"^ bacterial cells and 7.26 grams 

 dry bacterial substance, containing 0.819 gram nitrogen, per day. 

 The average of all examinations of Subject B was 26 x 10^^ bac- 

 terial cells and 3.56 grams bacterial dry substance, containing 0.393 

 grams nitrogen, per day. 



The nitrogen contained in the bacteria varied from 66.8 per 

 cent, to 23.3 per cent, of the total fecal nitrogen, the average of 

 all examinations being 46.3 per cent. Individual variation in this 

 respect was also considerable. In Subject I the average of all 

 examinations showed 57.4 per cent, of the total fecal nitrogen 

 contained in the bacteria; in Subject K this quantity was 32.1 

 per cent. These two subjects were the ones who showed the two 

 extremes (66.8 per cent, and 23.3 per cent., above) for the single 

 examinations. 



A detailed account of these experiments will be published in a 

 short time in The Journal of Infectious Diseases. 



