BACILLUS ANTHBACIS. 311 



sporulation and a germination of spores without oxygen 

 upon pieces of potato, quince juice, etc. (A. H. xxxv, 355). 



Upon fresh nutrient media spores germinate in a few 

 hours. 



Cultures which are not transferred for a long time often 

 lose spontaneousl)' the ability to form spores. The bacil- 

 lus may be deprived of its ability to form spores by culti- 

 vation upon nutrient media containing carbolic acid, or, 

 with more difficulty, upon media to which are added 

 bichromate or hydrochloric acid. Different cultures vary 

 much as to the ease with which they become asporogen- 

 ous. All agencies which reduce the virulence also operate 

 unfavorably upon the sporogenous function, yet these 

 properties are not necessarily associated ; there are viru- 

 lent asporogenous and absolutely non-virulent sporo- 

 genous varieties. Phisalix found in long cultivation at 

 4"2°, with frequent reinoculation, that the aljility to form 

 spores at 42° was gradually lost, but later the bacilli 

 were also unable to produce spores at 30° While at 

 first the sporogenous function was recovered by inocu- 

 lation of a mouse, after 14 reinoculations at 42° the 

 sporogenous function was finally completely lost. The 

 remaining virulence, still present at that time, after the 

 twentieth generation at 42° was also lost (C. B. xiii, 533). 



Viability and Resistant Properties of the Bacilli without Spores 

 (Compare Moment, A. P., 1892, 21). — (a) In cultures the B. anthracis 

 maintains itself (through spore-formation ! ) for many months. 



In water : In an inhabited aquarium Hiiber found it dead in three 

 to four days. 



In soil : Moist anthrax blood is rendered free of germs in twelve to 

 fourteen hours by sunlight. 



(J) Drying : According to Koch, they remain alive, when dry, for 

 five weeks at most ; also in large dried pieces of meat they die in a 

 few weeks. Bacilli in dried blood endure 92° for one and one-half 

 hours, are killed by light in vacuum in eleven hours, and with admis- 

 sion of oxygen in nine hours. 



(f ) Salting does not kill anthrax bacilli in ham in fourteen days, 

 but does in six weeks ( Peuch ) . 



(d ) Moist heat at 60° kills rapidly. 



(e) Cold : With an outside temperature of from — 1° to — 24° 

 (average of — 10.4°) bacilli in agar cultures were dead in great part 

 in twelve days and almost completely in twenty-four days. The few 

 which remained alive produced cultures with lessened power of pro- 

 ducing disease and of liquefying gelatin. 



