CHARACTERISTICS AND DISTRIBUTION OF THE 

 COLON-AEROGENES GROUP * 



L. A. ROGERS 



INTRODUCTION 



The results of a series of investigations carried on in this 

 laboratory on the gas-forming bacteria, commonly known as 

 the colon-aerogenes group, have appeared in various journals. 1 

 This paper has offered an opportunity to bring these results to- 

 gether and present them in a briefer and more concise form 

 t" an has been possible in the earlier papers. The results 

 which will be discussed in this paper represent the accumula- 

 tive work of a number of persons for which the writer has 

 no desire to take undue credit. Particular credit is due my 

 colleague, Dr. Clark, who has been responsible for the greater 



* Published by permission of the Secretary of Agriculture. 



1 L. A. Rogers, W. M. Clark and B. J. Davis, The Colon Group of Bac- 

 teria in Jour. Inf. Dis., 14, 3, pp. 411-475, 1914. 



L. A. Rogers, W. M. Clark and A. C. Evans, The Characteristics of Bac- 

 teria of the Colon Type Found in Bovine Feces in Jour. Inf. Dis., 15, 1, 

 pp. 99-123, 1914. 



Wm. Mansfield Clark, The Final Hydrogen Ion Concentrations of Cul- 

 tures of Bacillus Coli in Jour. Biol. Chem., 22, 1, pp. 87-98, 1915. 



L. A. Rogers, W. M. Clark and A. C. Evans, The Characteristics of Bac- 

 ttria of the Colon Type Occurring on Grains in Jour. Inf. Dis., 17, 1, 

 pp. 137-159, 1915. 



W. M. Clark and H. A. Lubs, The Differentiation of Bacteria of the 

 Colon- Aero genes Family by the Use of Indicators in Jour. Inf. Dis., 17, 1, 

 pp. 160-173, 1915. 



L. A. Rogers, W. M. Clark and H. A. Lubs, The Characteristics of Bac- 

 teria of the Colon- Aero genes Type Occurring in Human Feces. (Unpub- 

 lished. ) 



S. H. Ayers and P. Rupp, Simultaneous Acid and Alkaline Bacterial Fer- 

 mentations from Dextrose and the Salts of Organic Acids Respectively. 

 (Unpublished.) 



L. A. Rogers, The Occurrence of Different Types of the Colon- Aerogenes 

 Group in Water. (Unpublished.) 



W. M. Clark and H, A. Lubs, The Colorimetric Determination of Hi/dro- 

 gen Ion Concentration and its Application in Bacteriology in Jour. Bact., 

 2, 1, pp. 1-34 ; 2, pp. 109-136 ; 3, pp. 191-236, 1917. 



