BACTERIAL CELLULAR SUBSTANCE 65 



and weighed as pyrophosphate. The following results 

 were obtained: 



Weight of Weight of 



sample. phosphate. Weight of P. Per cent, of P. 



. 496 gram . 0475 gram . 01323 gram 2 . 68 



. 346 gram . 0380 gram . 1 059 gram 3 . 06 



The mean of these determinations, 2.87 per cent., agrees 

 quite closely with Levene's finding, 2.67 per cent, of phos- 

 phorus in the tubercle bacillus from mannite cultures. 

 Most observers report smaller results, but it should be 

 noted that our samples are free from fat and wax, and 

 therefore the percentage is higher than if calculated for 

 the cells not previously extracted with alcohol and ether. 



In view of the fact that the cellular substance, notwith- 

 standing the washings to which it has been subjected, 

 cannot be regarded as chemically pure, we have not 

 wasted time in making elementary analyses. Wheeler 

 has collected the nitrogen and ash determinations made 

 in bacterial cellular substance in this laboratory and has 

 arranged them in the following table: 



Substance. Per cent, of nitrogen. Per cent, of ash. 



Typhoid 11.55 5.70 



Colon 10.65 8.615 



Colon 8.38 



7.20 (air-dried) 



Tuberculosis 10.55 11.47 



9.27 (air-dried) 9.98 (air-dried) 



Anthrax 10.285 7.76 



Subtilis 5.964 10.83 



Proteus vulgaris 6.791 10.88 



Ruber of Kiel 10 . 655 6.71 



Megaterium 8.349 10.18 



Pyocyaneus 10.843 9.04 



Violaceus 11.765 6.90 



Sarcina aurantiaca .... 11.460 6.40 



As will be seen, the nitrogen varies from 5.964 per cent, 

 in subtilis to 11.765 per cent, in violaceus, and the ash 

 from 5.7 per cent, in the typhoid bacillus to 11.47 per cent, 

 in the bacillus tuberculosis. 

 5 



