INOCULATIONS WITH B. DIPHTHERIA. 287 



37° C, but most luxuriantly at the latter tempera- 

 ture. 



Its growth in the presence of oxygen is more active 

 than when this gas is excluded. 



Staining. — In cover-slip preparations made either 

 from the fauces of a diptheritic patient or from a pure 

 culture of the organism, it is seen to stain readily with 

 the ordinary aniline dyes. It stains also by the method 

 of Gram, but the best results are those obtained by the 

 use of Lofiler's alkaline methylene-blue solution ; this 

 brings out the dark points in the protoplasmic body of 

 the bacilli and thus aids in their identification. 



For the purpose of demonstrating the Loffler bacillus 

 in sections of diphtheritic membrane, both the Gram 

 method and the fibrin method of Weigert give excellent 

 results. 



Pathogenic Properties. — When inoculated sub- 

 cutaneously into the bodies of susceptible animals the 

 result is not the production of a septicsemia, as is seen 

 to follow the introduction into animals of certain other 

 organisms with which we shall have to deal, but the 

 bacillus of diphtheria remains localized at the point 

 of inoculation, rarely disseminating further than the 

 nearest lymphatic glands. It develops at the point in 

 the tissues at which it is deposited, and during its 

 development gives rise to changes in the tissues which 

 result entirely from the absorption of poisonous albu- 

 mins produced by the bacilli in the course of their 

 development. 



In a certain number of cases ' diphtheria bacilli have 

 been found in the blood and internal organs of individ- 



' Frosch : Die VerbreitungdesDiphtherie-bacillusimK8rperdesMensohen. 

 Zeit. fur Hygiene und Infectlonskranliheiten, 1893, Bd. xiii. p. 49-52 



