282 CLINICAL BACTERIOLOGY. 



unsuccessful. Pfeiffer also was often able to cultivate the 

 bacilli from the sputum or pus from the lungs directly upon 

 agar, but this did not take place invariably, and at times it was 

 quite impossible to continue the growth of such cultures in any 

 way. The explanation for this fact is that the bacilli developed 

 in the first culture when with the infecting material a trace of 

 blood was simultaneously transferred to the culture-medium. 

 Growth failed to take place, however, when the blood was 

 wanting, and thus also in all daughter-cultures. 



The development of influenza-bacilli takes place regularly, 

 and the culture obtained may be continued indefinitely,, if the 

 infecting material is inoculated upon a culture-medium contain- 

 ing blood, and best upon blood-agar tubes (p. 82). For the 



'*>**& i*'-.. 



*. % * 9?*. *-.-..^ -..., 



- 





*-**;: . Vvv. 



Fig. 62. Bacillus influenzae, from a gelatin-culture; X 1000 (Itzerott and Niemann). 



development of pure cultures Pfeiffer recommends the following 

 method : The infecting material bronchial sputum or fluid from 

 a bronchopneumonic infiltrated portion of the lung in a case 

 of influenza-pneumonia is rubbed up with one or two cubic 

 centimeters of bouillon to a homogeneous emulsion. By means 

 of a platinum loop some of this is inoculated upon blood-agar, 

 and also for control-purposes upon ordinary glycerin-agar, tubes, 

 care being taken to secure uniform distribution of the infecting 

 material upon the entire surface. The dilution of the sputum 

 in the bouillon is intended, in the first place, to separate the 

 influenza-bacilli to such a degree that isolated colonies will form 

 upon the blood-agar tubes. In the second place the hemoglo- 

 bin that may be present in the infecting material will be so 

 greatly diluted that the influenza-bacilli will be incapable of 



