BIO-CHEMICAL CHARACTERISTICS OF BACILLI. . 79 



Members of the group have been found in normal stools, 

 Castellani (1910V 33 ) food stuffs, Mullens (1904),( 34 ) and 

 Savage (1906-7), and certainly in one case in a water supply, 

 May (1911).^ 



The organism found by Thomassen (1897) (36) in calves 

 suffering from nephritis and cystitis probably also belongs 

 to this order. 



General Characteristics of the Gaertner Group. 



These organisms all belong to the great colon family by 

 virtue of their morphology, staining reactions, nature of 

 growth on agar and their failure to liquefy gelatin or 

 peptonise milk. 1 Certain of their biological attributes are 

 now generally recognised, and the following description 

 will, I think, be an accurate enough presentation of present 

 day views on the characteristics of organisms certainly 

 able to be included in the group. They all agree with 

 bacillus coli in morphology and staining reactions. They 

 may or may not be motile. They, like b. coli, do not 

 liquefy gelatin or peptonise milk : and they differ from b. 

 coli, in not fermenting lactose, not clotting milk, and in 

 producing little or no indol ; and from bacillus typhosus in 

 producing gas on glucose. I think it is recognised also 

 that cane-sugar should not be attacked, and that acid and 

 gas should be produced on mannit, i.e., that such non- 

 mannit fermenting organisms as Morgan's No. 1, and such 

 saccharose fermenters as are fairly commonly found in 

 faeces should be relegated to quite different categories. 



The object of the paper is to enquire into the bio-chemical 

 characteristics of organisms agreeing with the above 

 description. The two principal methods used to identify 

 and classify Gaertner type organisms are the agglutination 

 method, including also Pfeiffer's test and the absorption 



1 Not obviously though the "clearing" referred to later may be of 

 this nature. 



