. A text-book of bacteriology. Bacteriology. THE BACILLUS OF ANTHRAX. 436 temperature of 20° to 38° C. Development ceases at temperatures below 12° C. or above 45° C. This bacillus grows best in neutral or slightly alkaline media, and its development is arrested by a decidedly acid reaction of the cul- ture medium. It may be cultivated in infusions of flesh or of vari- ous vegetables, in diluted urine, in milk, etc. In gelatin plate cultures small, white, opaque colonies are devel- oped in from twenty-four to thirty-six hours, which under the micro- scope are seen to be somewhat irregular in o
. A text-book of bacteriology. Bacteriology. THE BACILLUS OF ANTHRAX. 436 temperature of 20° to 38° C. Development ceases at temperatures below 12° C. or above 45° C. This bacillus grows best in neutral or slightly alkaline media, and its development is arrested by a decidedly acid reaction of the cul- ture medium. It may be cultivated in infusions of flesh or of vari- ous vegetables, in diluted urine, in milk, etc. In gelatin plate cultures small, white, opaque colonies are devel- oped in from twenty-four to thirty-six hours, which under the micro- scope are seen to be somewhat irregular in outline and of a greenish tint; later the colonies spread out upon the surface of the gelatin, and the darker central portion is surrounded by a brownish mass of wavy filaments, which are associated in tangled bundles. Mycelial- like outgrowths from the periphery of the colony may often be seen extending into the surrounding gelatin. At the end of two or three days hquefaction of the gelatin commences, and the colony is soon surrounded by the liquefied me- dium, upon the surface of which it floats as an irregular white pellicle. In gela- tin stab cultures growth occurs all along the line of puncture as a white cen- tral thread, from which lateral thread- like ramifications extend into the culture medium. At the end of two or three days liquefaction of the culture medium commences near the surface, where the development has been most abundant. At first a pasty, white mass is formed, but as liquefaction progresses the upper part of the liquefied gelatin becomes transparent from the subsidence of the motionless bacilli, and these are seen upon the surface of the non-liquefied portion of the medium in the form of cloudy, white masses, while below the line of liquefaction the charac- teristic branching growth may still be seen along the line of puncture. In agar plate cultures, in the incubating oven at 35° to 37° C, colonies are developed within twenty-four hours, which under
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