XII] PATHOGENIC BACILLI : GROUP C 269 



pathognomonic value, or their absence as of diagnostic 

 importance. 



The same conclusion is arrived at by Pfuhl (Centralbl. 

 f. Bakt. und Parasit. xi, No. 13) and by Pfeiffer and Beck 

 {Deutsche Med. Woch., May 26th, 1892). 



A large number of experiments were made on rabbits 

 and monkeys by using either bronchial sputum of influenza 

 cases containing an abundance of the Pfeiffer influenza bacilli 

 — the majority of the experiments — or of cultures of these 

 bacilli, and by introducing such materials under the skin or 

 into the trachea, or by direct injection into the vein 

 (rabbits), but it has not been practicable to arrive at any 

 definite production of influenza disease in monkeys or in 

 rabbits. Only in one monkey out of eighteen was a 

 definite disease of the lungs produced by such injection, 

 and there (but in company with other bacilli) clumps of 

 influenza bacilli were found ; while among thirty rabbits 

 injected with like materials there was no single instance of 

 a disease recognisable as influenza in nature having resulted 

 from the experiment. 



Now the question has repeatedly been raised, and indeed 

 has been repeatedly answered in the affirmative, viz., whether 

 the disease of influenza, such as prevailed in this country, 

 on the Continent of Europe, and in most other parts of the 

 world in 1889-1890 and in 1891-1892, is a disease to which 

 also the domestic and other animals are subject. It has 

 been particularly asserted that in this country influenza 

 was common amongst horses antecedently to and during 

 the prevalence of influenza in man. 



Though we have not made intentional experiments upon 

 horses or other animals beyond those mentioned in these 

 pages, we have not the less been on the watch during the 

 time that we carried on our inquiry (February to April, 1892) 



