BIO-CHEMICAL CHARACTERISTICS OF BACILLI. 75 



and from certain diseases in animals, notably from swine 

 fever, show certain well defined biochemical attributes 

 which demark them from most other coliform bacilli, but 

 which, with one exception, are of little use in separating 

 types in the group. The notable exception is that of the 

 organism found associated with swine disease; this is dis- 

 tinctly marked out from the rest of the group by its 

 apparently absolute inability to ferment arabinose, a pen- 

 tose sugar readily attacked by all other members of the 

 group. 



The biochemical work in this paper has been repeated 

 frequently, and twenty-two tests have been employed in 

 the attempt to differentiate the group. Much of the work 

 done here is substantially in agreement with previous 

 workers, but, as far as I am aware, has never before been 

 attempted by one author on such a large number of organisms 

 and with such a large number of tests. 



The use of arabinose as a differentiating agent between 

 the swine bacilli and the remainder has not so far been 

 noted, although at least one authority had he gone a little 

 further must have made the discovery. 



The rest of the paper is made up by a review of certain 

 organisms similar to, but differentiable from, the true 

 Gaertner- Paratyphoid-Food poisoning or Swine disease 

 strains. These are especially interesting, as the reactions 

 given by these organisms are in most cases very close to 

 the true type, and might, unless especial care be taken, be 

 mistaken for the true type, 



A note is made of one true to type Gaertner organism 

 isolated from the blood of a case of erysipelas, from which 

 streptococci were also found. Also appended are the 

 biochemical reactions of certain organisms of very different 

 type, but which, resembling in some few respects bio- 

 chemically, and also in their pathogenic relationship, 



