223 



Judging from the material we are now dealing with it would 

 be wrong to exclude bacteria from the class Pfeiffer's bacillus 

 on the ground of such factors as occurrence or virulence. That 

 bacteria to which this designation must be given by no means 

 exclusively occur in influenza, and that a clear distinction 

 between virulent and avirulent forms cannot be drawn, is 

 admitted. Thus the justification vanished for excluding Mul- 

 ler's trachoma bacillus because it was cultivated from con- 

 junctiva attacked by trachoma; Jochmann & Krause's „Bacil- 

 lus pertussis Eppendorf", because it was cultivated from 

 whooping-cough: Meunier's bacillus; Cohen's bacillus and many 

 others because they could produce septicaemia in man and ani- 

 mals. Nor can we exclude Elmassian's bacillus, Luzzato's 

 „Bacillus minutissimus sputi", or Jundell's „Bacillus catarrha- 

 lis" on account of statements that they can grow on ascitic 

 agar. If a number of strains were simultaneously cultivated 

 on ascitic agar and it was repeatedly shown that some grew 

 and others did not, then we could assert that the latter 

 possessed particular nutritive requirements. But nothing can 

 be concluded from the demonstration of growth on ascitic 

 agar which has not been controlled with regard to its freedom 

 from haemoglobin either by the benzidin test or by the ino- 

 culation of undoubted Pfeiffer's bacilli. 



In accordance with these views, as far as I can see all the 

 reports on the finding of haemoglobinophilic bacteria in man 

 to which exception has not been taken in the above, may be 

 looked upon as referring to Pfeiffer's bacillus. This also applies 

 to the rarer habitats such as the biliary passages (Heyrovsky, 

 Klieneberger (1), Laubenheimer, Knina), urinary tract (Kretz, 

 Cohn, Klieneberger (3)), uterus (Thalhimer (1)), Fallopian 

 tubes (Kisskalt). 



Our investigations into the classification of the haemoglo- 

 binophilic bacteria have lead to the following conceptions: 



(1) Haemoglobinophilic bacteria (as a group 

 designation) in the strictest sense of the word are identical 

 with Pfeiffer's bacillus. On the other hand this species 

 must be more extended than we have often been inclined to make 



