THE BACILLUS OF WHOOPING-COUGH. 477 



bronchopneumonia as a complication, in various diseases, and also 

 frequently in a pure state in simple coryza. These findings agree 

 with the facts of certain of our predecessors, notably with those of 

 Elmassian. 



In short, this organism, which resembles the one described by 

 Pfeiffer as the cause of influenza, is certainly not the cause of whoop- 

 ing cough. / We have this year been able to isolate a specific bacil- 

 lus, since we have had at our disposition favorable cases, among 

 which the one that furnished our first successful culture may be 

 mentioned in some detail. It was a male child of two months, 

 nursed by its mother, in excellent health, who had been contamin- 

 ated by a neighbor's child who later on showed a most characteristic 

 case of whooping-cough. The child began to cough and the charac- 

 teristic paroxysms soon came; during one of these paroxysms a 

 white bit of exudate which was extremely rich in leucocytes was 

 coughed up. This exudate contained enormous numbers of a 

 micro-organism which was identical with the one we had seen 

 several years before and in a similar condition of purity and 

 abundance.* 



This exudate was shaken up in salt solution so as to form various 

 dilutions and these dilutions were inoculated on our medium. The 

 surface of those tubes that had been inoculated with a relatively 

 concentrated dilution, in which, therefore, the specific organism 

 was present in large numbers, showed, instead of a uniform growth 

 at the end of 2 days, only a few contaminating colonies (some 

 coccus that occurs in the saliva). The platinum loop, however, 

 removed, from the part of the surface of the culture which appeared 

 to be sterile, a large number of the organisms that were being 

 sought for. It appeared as if multiplication had actually taken 

 place but was too slight to give rise to visible colonies. f This 

 organism, implanted on a second tube, grew much better, giving 

 rise to a definite line of implantation, and the culture then became 

 luxuriant. Morphologically the identity of this organism with 



* On successive days the quantity of bacteria progressively diminished. The 

 paroxysms continued for about 3 weeks and the child got well after complica- 

 tions. 



t At times we have found that certain individual micro-organisms give rise to 

 distinctly visible colonies in 2 or 3 days even in the first culture. This, however, 

 is the exception. 



