222 



THE INFECTIOUS DISK ASKS. 



The lungs may show small haemorrhages aiid cedema, and the bronchi 

 may be deeply congested. The plenral cavities may contain serum. 

 The intestines may exhibit the lesions of the so-called intestinal mycosis. 



FIG. 105. BACILLUS ANTHRACIS GROWING IN THE BLOOD-VESSELS OF THE LIVER OF A MOUSE INOCU- 

 LATED WITH A PURE CULTURE OF THE BACILLUS. 



The bronchial and other lymph-nodes may be swollen. The spleen may 

 be swollen, very dark in color, and soft, sometimes almost diffluent. 



The bacillus may be found, usually in large numbers, in the spleen 

 and in the capillary blood-vessels, especially in the liver (see Fig. 105), 

 lungs, kidneys, and intestine. ! 



Characters of the Bacillus Anthracis. 



The Bacillus authracis is from 5 to 20 fj. long and about 1 fj. broad, capsulated, and 

 is often uneven along the sides. The ends of the bacilli are square or slightly con- 

 cave, and the bacilli often hang together end to end, forming thread-like structures 

 (Fig. 106). While the bacilli in the vegetative condition are easily- killed, they de- 

 velop spores outside of the body only, and these are very invulnerable to the action of 

 the ordinary germicidal agents and to heat, resisting often for many days the action of 

 from two to five-per-cent carbolic acid and defying for 

 some minutes the action of live steam. Anthrax bacilli 

 are immobile, sometimes capsulated, and are easily 

 stained by the auilin dyes. They grow readily on arti- 

 ficial culture media at ordinary room temperatures, fluid- 

 ifying gelatin and usually growing out, before they do 

 so, in a network of delicate filaments into the solid me- 

 dium. 



Subcutaneous inoculation of cultures of the anthrax 

 bacillus into various species of animals induces charac- 

 teristic lesions. White mice and guinea-pigs are espe- 

 cially susceptible, usually succumbing to the anthrax 

 septicaemia in from two to four days. Serous exuda- 

 tions, often bloody and with many bacilli, develop at the seat of inoculation, while in the 

 blood multitudes of the bacilli are found. 



1 For bibliography and resume of Anthrax see Sobernheim, Kolle and Wassermann's 

 "Eandbuch der Mikrborganismen," Bd. ii , p. 1 



FIG. 106. BACILLUS ANTHRACIS 

 CONTAINING SPORKS. 



From a culture. 



