BACILLUS OF MALIGNANT (EDEMA 161 



the bacilli of anthrax can be detected in the blood. They 

 also differ essentially from the latter in appearance, being 

 thinner and ending in rounded points. They unite to form 

 curved threads, possess the power of automatic movement, 

 depending, as E. Pfeiffer has found, upon flagella, and form 

 central spores. 



The bacilli soon lose their motility in the hanging drop, 

 access of oxygen being fatal to them, as they are strictly 

 anaerobic. Growth takes place either at the temperature 

 of the room or at that of the incubator. They stain quickly 

 in aniline dyes, but the colour is easily discharged by ap- 

 plying Gram's method. Consequently, the points on which 

 reliance is to be placed in distinguishing between the bacilli 

 of malignant oedema and those of anthrax are the form, 

 motility, distribution in the organs, manner of staining, 

 and relation to oxygen. 



In gelatine cultures, which must be made with a regard 

 to their strict anaerobioqis, small colonies occur, the contents 

 of which soon liqu«fy, so that each forms a liquid globule 

 in the interior of the gelatine. In the high cultures there 

 is soon seen, as Liborius pointed out, an extensive decom- 

 position of the nutrient medium, which is changed into a 

 turbid fluid with simultaneous disengagement of abundant 

 bubbles of gas (fig. 59). The addition of grape sugar to the 

 gelatine mayprove advantageous. Dull, cloudy, indistinctly- 

 defined colonies of a shaggy appearance show themselves 

 on agar after eight hours. They consist of a closely-woven 

 network of finely granulated fibres, and develop lenticular 

 gas-bubbles ; indeed, this development of gas is so abundant 

 that thick layers of agar are thrown towards the upper part 

 of the test-tube, while a considerable quantity of a cloudy, 

 whitish liquid condenses and gathers at the bottom. A 

 network of bacilli forms on potato at incubating heat. The 

 temperature most suitable for their growth lies between 37° 



