416 MICRO-ORGANISMS IN WATER 



BACILLUS ANTHPvACIS 



LIQUEFIES GELATINE 



Authority. — Eayer and Do.vsiiue, Bulletin de la SocUU de Biologie deParis, 

 1850. Pollender, Vierteljahrschr. f. gcs. Med., vol. viii., 1855. Pasteur and 

 Joubert, Comptes rendus, 1877. Koch, Cohn's Beitrdge z. Biologie d. Pflanzen, 

 vol. ii. Heft. 2, 1877 ; also ' Zur Aetiologie des Milzbrandes,' Mittlieilungen a. d. 

 kaiserlichen Qesundheitsamte, vol. i., 1881, p. 49. 



"Where Found.— In the blood of animals dead of anthrax. Diatroptoff 

 {Annales de VInstiUit Pasteur, vol. vii., 1893, p. 286) found this bacillus in the 

 sediment at the bottom of a well, the water from which had communicated 

 anthrax to a flock of sheep. 



Microscopic Appearance. — The bacillus is 1 to 1*5 /a broad, and 3 to 6 to 10 ^u 

 long, with square cut ends. Eorms long threads in broth at 36° C. It 

 is notmotile. Forms spores between 18° and about 40° C. ; at 37° they are pro- 

 duced in about twenty-four hours, at 21° C. in about seventy-two hours. The 

 spores appear in the middle of the rod and are only produced in the presence of 

 oxygen, and henceare never formed in the body of an animal. They are stained 

 best by means of Ehrlich's aniline fuchsin_ solution (see p. 45). The bacilli 

 stain readily with the usual aqueous solutions. 

 , Cultures. — 



Gelatine Plates. — Under a low power the depth colonies are circular and 

 consist of twisted and knotted bands of threads closely packed together, which 

 give an irregular appearance to the edge. On the surface the colonies consist 

 of masses of convoluted threads extending in all directions and producing the 

 most varied appearance, sometimes recalling a medusa head, whilst colonies 

 consisting entirely of banded threads with long curled whip-hke projections are 

 also found. The gelatine is liquefied. 



Gelatine Tubes. — The gelatine becomes liquid and very frequently fine 

 hair-like extensions ramify from the needle's path in the depth into the adjacent 

 gelatine. 



Agar-agae. — Forms a dry, grey white expansion. 



Potatoes. — Produces an abundant although restricted dry white growth. 



Blood Serum.— Liquefies the serum. 



Bemarks. — No sulphuretted hydrogen is produced in broth-cultures (Stagnitta- 

 Balistreri). It is pathogenic to numerous animals, and produces wool-sorters' disease 

 or malignant pustule in man. "White mice die in twenty-four hours after inoculation. 

 Chamberland and Boux {Comptes rendas, 1883, p. 1090) succeeded in producing a 

 race of bacilli from anthrax blood permanently incapable of producing spores (asporo- 

 gene anthrax), the virulence of which is not affected. For this purpose an addition 

 of ^^i_ to ■^^^ of potassium dichromate is made to ordinary broth. Pasteur obtained 

 anthrax vaccine by cultivating the bacilli in broth at between 42° and 43° C. Tous- 

 saint prepared vaccine by heating virulent anthrax bacilli for ten minutes at 55° C. 

 It will not growbelow 12-14° C, nor above 45° C. B. suhtilis (see p. 417) resembles the 

 anthrax bacillus, but has rounded ends and is not pathogenic to animals. For the 

 effect of insolation on the bacillus see Chapter IX. Schild [Zeitschriftf. Hygiene, vol. 

 xvi., 1894, p. 388) states that anthrax spores are destroyed in a formalin solution of 

 1 : 1000 in 1 hour (see note p. 285). 



