TMMTTNITT AGAINST MICROBES. 437 



rabbits died in four days and the other in less than three. The 

 four animals showed the characteristic signs of anthrax (bacilli 

 in the blood and organs^ hypertrophy of the spleen^ oedema of 

 the skin, in the. rabbit and guinea-pig, &c.). 



Similar facts^ have been observed in fowls when these animals 

 which are immune against anthrax are inoculated with this 

 virus. When, however, these animals are placed in cold water 

 they readily die when inoculated with anthrax, and Wagner 

 has shown that the phagocytes in the latter case are unable to 

 cope with the bacilli, though they may make an attempt to do so. 



I have shown elsewhere that in diphtheria of man a struggle 

 takes place in the diphtheritic membrane between the leuco- 

 cytes and the specific microbes, and that the disease is localised 

 in the upper part of the respiratory tract owing to the action of 

 the former. In thin sections passing through the entire false 

 membrane and the surrounding structures — a section of a small 

 bronchus, for instance, when the disease has extended into the 

 lungs — the most superficial part of the membrane, that is the 

 free edge of the lumen of the tube, is found to contain an enor- 

 mous number of specific bacilli, lying, for the most part, quite 

 free in the exudation fluid (fig. C). The micro-organisms re- 

 semble short rods of the size of tubercle bacilli, and are often 

 aggregated together in clusters containing hundreds of microbes. 

 So thick is this layer of micro-organisms at times that on holding 

 the sections to the light a thin violet line is seen running along 

 the inner margin of the section tube, this line representing the 

 layer of microbes (fig. E, a). Scattered among these specific 

 bacilli, more especially in the upper air-passages, other kinds 

 of microbes — micrococci and bacilli of various sizes and shapes 

 — are also met with. 



If the false membrane immediately below the superficial 

 layer just described be now examined, the number of micro- 

 organisms is found to be exceedingly small (fig. E, b) ; and it 

 will be noticed that not a single bacillus is to be seen in the 

 deeper layers of the false membrane, in the mucous membrane, 



' Wagner, "Le Charbon des Poules," ' Aimales del'Institut Pasteur, Sept., 

 1890, p. 573. 



