43 



by haem'oglobinophilic bacteria, but merely to utilise as much 

 as is necessary for the discussion of the position of these 

 bacteria in the classification of organisms. 



When meningitis and septico-pyaemia are mentioned toge- 

 ther it is because we have to deal with a whole group of 

 diseases which turn upon the occurrence of the bacilli in 

 question in the blood as the chief phenomenon. We have to 

 deal partly with meningitis without other lesions, and partly 

 complicated with purulent processes produced by the same 

 microbe in other situations, particularly in the joints. Further, 

 we have pyaemia and septicaemia (endocarditis) without me- 

 ningitis. Frequently we find the organism at the same time in 

 the ordinary sites of election of Pfeiffer's bacillus (lungs, throat, 

 accessory nasal sinuses, and middle ear). 



Wollstein (3) like Cohen, on injection of haemoglobino- 

 philic bacteria from' meningitis cases, into rabbits could usually 

 cultivate them from the animal's blood in large quantities, 

 but this was generally not the case with the haemoglobino- 

 philic bacteria from the respiratory tract. She looks upon 

 this difference in virulence only as one of degree which cannot 

 form the basis of any division into two well defined groups 

 It appears from Henry's and Ritchie's works that the hae- 

 moglobinophilic bacteria from 1 meningitis are on the whole 

 more virulent for different animals than Pfeiffer's bacilli obtained 

 from the respiratory organs but that this difference is not 

 always so marked that it can be made the criterion of a 

 definite boundary between the „meningeal a and the Respira- 

 tory" strains. This view is, on the whole, supported by the 

 other literature bearing on the subject. (In this connection 

 particular mention may be made of the lists of litterature by 

 Cohen, Henry, Ritchie, Torrey, Anderson & Schultz, and 

 Bender). 



As regards morphological and „cultural" characters the 

 haemoglobinophilie bacteria from the meninges and blood 

 exactly resemble Pfeiffer's bacillus, according to practically all 

 the work upon the subject, — even that of Cohen and Cohen 

 & Fitzgerald. Besides differences in virulence between 

 meningeal and respiratory strains, certain serological distinc- 

 tions have been demonstrated (Cohen, Wollstein (3)). In view 

 of the great serological differences which have been demon- 



