xni] MICROBES OF MALIGNANT ANTHRAX 281 



In streak culture on gelatine the streak of inoculation is 

 marked after twenty-four to forty-eight hours as a whitish- 

 grey line ; then a number of whitish fine threads shoot out 

 horizontally from this line, liquefaction at the same time 

 commencing and proceeding slowly and gradually; the 

 line thickens and broadens, and after a week is made up of 

 masses of threads twisted and convoluted, and forming a 

 thick, white, filmy patch, which as liquefaction proceeds 

 sinks to the bottom of the liquefied gelatine, forming here 

 a whitish grey fluffy mass. 



In neutral or faintly alkaline broth kept at 36-38° C. 

 there is, if the broth be thin, uniform slight turbidity after 

 thirty-six to forty-eight hours : flakes small and large then 

 appear at the bottom of the fluid, while this latter remains 

 fairly clear. As growth proceeds, about the end of the 

 week, there are contained at the bottom of the fluid 

 characteristic greyish, fluffy, loose, nebulous masses, which 

 are masses of anthrax threads matted together ; these 

 masses increase in bulk and extend as it were from the 

 bottom of the fluid towards the upper parts. If during 

 the first few days some of the flakes remain adhering to the 

 glass at the surface of the fluid, these flakes enlarge and 

 form on the glass, on a level with the surface of the fluid, 

 a sort of whitish ring, somewhat like a pellicle ; in this 

 copious spore formation takes place ; but in the tubes, in 

 which all the growth is limited to the deeper parts of the 

 fluid, no spore formation occurs at any time, since for the 

 formation of spores a free and copious supply of oxygen is 

 required. 



On Agar mixture at 36-38° C. a greyish, thick film is 

 noticed after two days along and beyond the line of in- 

 oculation. This rapidly increases in breadth till the whole 

 surface of the Agar is covered with a sticky, pasty, greyish 



