xill] MICROBES OF MALIGNANT ANTHRAX 259 



form large masses (see Fig. 121). In the mucous mem- 

 brane next to, but not part of, the diphtheritic membrane 

 the writer has found them occasionally in small numbers ; 

 in the inflamed mucous membrane of the depth these diph- 

 theria bacilli are, as a rule, rarely to be found. In the 

 blood and in the viscera the bacilli are generally absent ; 

 nor are other micro-organisms to be found as constant 

 inhabitants. In cases of diphtheria ending fatally, even 

 if the disease only lasted a few days, the lungs are the 

 seat of severe bronchial catarrh, lobular or broncho- 

 pneumonia, with numerous diphtheria bacilli ; the kidney 

 is congested and shows distinct parenchymatous nephritis : 

 the epithelium of many convoluted tubes of the cortex is 

 granular, disintegrating, and fatty ; in the liver fatty 

 degeneration of the liver cells is generally present. The 

 one species of bacteria that is constant and can be easily 

 isolated in many cases in almost pure cultivation from the 

 superficial and even middle layers of the fresh diphtheritic 

 membrane consists of non-motile minute bacilli : some are 

 curved, most are straight, some slightly swollen at each end or 

 knob-shaped at one end, many of them pointed at one end ; 

 in fact, this latter may be regarded as the typical bacillus. 

 These bacilli occur either singly or in dumb-bells, or aggre- 

 gated in continuous masses ; many show a segi^egation of their 

 protoplasm into granules or rods of unequal size ; amongst 

 these " granular " forms one or both terminal granules are 

 occasionally club-shaped. Some of the single bacilli in well- 

 stained specimens show a deeply stained granule at each end. 

 The bacilli of Agar cultures show the same appearances as 

 those in the diphtheritic membrane ; in gelatine culture the 

 bacilli are shorter, thicker, and many are conical (see Fig. 123). 

 These bacilli were first seen by Klebs, and by Loffler were 

 regarded, owing to their constancy, as pathognomonic and 



