502 PRACTICAL BACTERIOLOGY. 



isolated, but occasionally by good fortune one may be 

 found attached to a bacillus. 



Under favourable conditions, and especially quickly 

 at blood heat, the Rauschbrand bacillus forms spores 

 of an elliptical shape. They lie towards one extremity 

 of the rodlet, and are thicker than it, so that one part, 

 a short distance from the end, becomes swollen. As 

 a rule mature spores are found on the third day in 

 cultures that have been kept warm. The spores 

 require to be doubly stained in order to be rendered 

 visible, the result in this case is specially satisfactory, 

 as the spores are so large. 



An organism, very similar in its behaviour towards 

 oxygen, is the bacillus of malignant oedema {BaclMux 

 wdematis maligni) which is distributed everywhere in 

 nature, being present in dung, in manured earth, in 

 several putrifying liquids, etc. It is pathogenic in 

 many very different organisms, but it appears only to 

 occur in man, when through other circumstances the 

 system has been weakened. 



This bacillus can be fairly certainly obtained if 

 samples of garden mould taken from the surface of 

 various places, down to about 1^ centimetres in depth, 

 are well mixed together, and cultivations are made 

 either directly with some of the mixture, or from the 

 liquid in which it has been soaked. It is best, as 

 before, to prepare Esmarch tube cultures in an atmo- 

 sphere of hydrogen, and to keep them at a temperature 



