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Contents. 



Preface 9 



I. Historical Review. 



* Introduction 13 



(General considerations (13) — Orientating list of the Contents of the 

 Review of the Literature (15)). 



J Pfeiffer's Work 17 



(Critical Views (17) — The first Reinvestigations (20)). 



Account of the Occurrence of Pfeiffer's Bacillus v 20 



(Resume (20) — Interval between the Two Pandemics (24) — The 

 Years Immediately Preceding the Pandemic 1918 — 20; „The Prelimi- 

 nary Epidemics" (30) — The Epidemic in Spain in May 1918 (31) — 

 The Investigations in Pfeiffer's Institute (32) — Other Positive Findings 

 Immediately after the Beginning of the Pandemic (33) — Increasing 

 Frequency of Occurrence During the Course of the Pandemic (34) — 

 Decreasing Frequency of Occurrence During the Decline of the Pandemic 

 (35) — Can the Negative Findings be Explained on the Ground of 

 Defective Technique? (35) — Proofs of Nonuniform Occurrence (36) — 

 Examples of the Wide Distribution of Pfeiffer's Bacillus (36) — The 

 Accessory Sinuses of the Nose (38) — Healthy Persons (38) — Other 

 Diseases than Influenza (38) — The Occurrence in Influenza Pre-emi- 

 nently in the Early Stages of the Disease (39) — Blood and Internal 

 Organs (39) — Animals (40)). 



The Occurrence of Pfeiffer's Bacillus in the Blood, Meninges etc.; Virulence 40 

 (Pathogenicity for Animals (41) — Meningitis and Septico-Pyaemia in 

 Man (42)). 



Morphology 46 



Biochemical Reactions 48 



(Indol Formation (48) — Fermentation Reactions (49)). 



Serological Reactions 51 



(Agglutination and Complement Fixation in Human and Animal Sera; 

 The Serological Differences between Various Strains of Pfeiffer's Bacillus 

 (51) — On the Constancy of the Serological Reactions (55)). 



