CHAPTER XV 



ANAEROBIC BACILLI 



The group of microbes which we now proceed to describe 

 comprises several species of specific pathogenic bacilli which 

 have the following characters in common : — (i) They are 

 obligatory anaerobic, growing therefore best, in fact growing 

 only, when not in contact with air (oxygen) ; (2) they are 

 strong gas-formers — methan or marsh gas ; (3) they are 

 cylindrical bacilli, more or less capable of forming chains 

 and filaments ; (4) they are motile, and possessed of several 

 and sometimes numerous flagella ; (5) they form bright oval 

 spores (endospores) thicker than the bacilli, which spores 

 just like those mentioned of other bacilli (bac. subtihs, bac. 

 mesentericus, bac. anthracis) have a great resisting power to 

 heat, so that while the sporeless bacilli are killed by heat of 

 65-70° C. in ten or five minutes respectively, the spores do 

 not lose their germinating power by being heated up to 

 8o°-8s° for ten or fifteen minutes ; (6) they grow well in 

 the depth of grape-sugar gelatine and liquefy this. 



They differ among themselves in (a) the nature of the 

 disease they cause in the animal body, (i) their distribution 

 in the body of the infected animal, (c) the nature and 

 rapidity of their growth in artificial media, (d) the rapidity 



