430 SUMMARY OF CURRENT RESEARCHES RELATING TO 



The preceding table gives the cultural reactions of the three 

 organisms, and also of the " vibrion septique " (original strain from 

 Pasteur Institute, which appears in reality to be Rauschbrand) and 

 B. tetani. 



The pathogenic anaerobes may thus be conveniently divided into 

 four groups as follows : — 



Group A. — 'The Eauschbrand group (Bacillus of Rauschbrand, Bacillus 

 of Ghon and Sachs, Bacillus of Xovy), containing forms which do not 

 digest the proteins ; they do not liquefy inspissated serum or produce 

 blackening in meat or " hernbrei " medium. They clot milk without 

 much shrinkage of the clot ; they are able to liquefy gelatin ; they are 

 usually motile, but this character is liable to variation. Spores are 

 formed in all the media, but an alkaline reaction favours their 

 production ; the spores are central or subterminal. The group for the 

 most part is very pathogenic to laboratory animals. They are very 

 strict anaerobes. 



Group B. — The perfritn/ens group contains forms which have very 

 little capacity for attacking the proteins. The strains belonging to this 

 group do not liquefy inspissated serum or blacken meat or " hernbrei." 

 They clot milk, producing a hard tough clot much broken by gas ; the 

 reaction is acid, and a strong odour of l)utyric acid is given off. There 

 is no obvious digestion of the clot. They are non-motile, with the 

 exception of B. enteridiUs sporof/enes (Klein). The colonies are smooth ; 

 spores are not formed, except on alkaline media rich in protein and 

 containing a little fermentable sugar. The organisms are pathogenic. 



Group G {B. amylohactor, von Hibler No. 9) may be recognized by 

 their inability to liquefy gelatin ; they are incapable of attacking 

 the proteins, and do not liquefy inspissated serum or blacken meat 

 media. 



Group D (B. cBdematis maligtii, B. tetani, B. botulinus, B. cadaveris 

 sporof/enes) may be called the proteolytic group, and is characterized by 

 its very active powers of digesting media rich in protein. Milk is 

 digested usually without the production of clot, though a precipitation 

 of casein may occur ; inspissated serum is liquefied, meat media 

 blackened and digested, and gelatin is liquefied ; their growth produced 

 a penetrating odour of putrefaction. They are actively motile. The 

 colonies have a characteristic appearance, and grow out in long tangled 

 filaments at their edges. Such members as B. tetani and B. botulinus 

 are sharply marked off by their characteristic toxins and other 

 peculiarities, but they are none the less closely allied to the rest of the 

 group in their cultural reactions. 



The composition of the cooked meat medium and the alkaline egg 

 fluid referred to is as follows : — 



Cooked Meat Medium. — Eight ounces of bullock's heart, minced very 

 fine and then ground in a mortar ; add eight ounces of tap water and 

 heat slowly so as to cook the meat thoroughly ; add normal sodium 

 hydrate until the medium is alkaline to litmus. Divide into tubes and 

 autoclave. 



Allcaline Egg Fluid. — This is a modification of Besredka's medium. 

 The yolk of one q^^ and the whites of two are beaten up in a beaker ; 

 add 6 c.cm. of normal sodium hydrate ; add 500 c.cm. of Lap water by 



