382 MANUAL OF DETERMINATIVE BACTERIOLOGY 



Key to the species of genus Corynebacterium. 



I. From human sources.* Non-motile. f 



A. Aerobic. No liquefaction of gelatin. 



1 . Acid from glucose and usually maltose and galactose. Usually no acid from 



sucrose. Causes diphtheria. 



1. Corynebacterium diphtheriae. 



2. Not as in 1. 



a. No acid fi'om carbohydrates. 



2. Corynebacterium pseudodiphtheriticum. 

 aa. Acid from glucose and sucrose. 



b. Highly pleomorphic, varying from cocci to rods. 



3. Corynebacterium enzymicum. 



bb. Rods with polar staining with club forms, diphtheroid in ap- 

 pearance. 



4. Corynebacterium xerose. 



bbb. Rods as above but characteristic salmon pink growth on 

 coagulated blood serum. 



5. Corynebacterium hoagii. 



B. Microaerophilic to anaerobic. Growth feeble or none at all on gelatin. 



6. Corynebacterium acnes. 

 II. From domestic and laboratory animals. Non-motile. 



A. Acid from glucose. 



1. Grows poorly if at all on ordinary gelatin and agar. Slow liquefaction of 



serum gelatin and coagulated blood serum. Causes suppurative pro- 

 cesses in cattle, swine, and other animals. 



7. Corynebacterium pyogenes. 



2. No liquefaction of gelatin or blood serum. Grows poorly, if at all, on 



ordinary gelatin and agar. 



a. Cause of pyelonephritis in cattle. 



8. Corynebacterium renale. 



aa. Found in caseous nodules resembling those of tuberculosis. Found 

 in sheep, horses and some other animals. 



9. Corynebacterium pseudotuberculosis. 

 aaa. From caseous nodules in mice. 



10. Corynebacterium kutscheri. 

 aaaa. Causes a septicemia in mice. 



11. Corynebacterium murisepticum. 



B. No acid from carbohj^drates . No liquefaction of gelatin. 

 1. From milk and bovine udder. 



12. Corynebacterium bovis. 



* Habitat relationships are used because comparative studies of the species in the 

 genus are still completely lacking. 



t The reports of motile species in this genus present a puzzling problem, particu- 

 larly as the motile species of plant pathogens placed in the genus are polar flagellate. 

 Some students of the group feel that, if motile species really exist, they should be 

 placed in a separate genus. Others feel that a more careful study of the described 

 polar flagellate species will show that these species really belong elsewhere. Where 

 authors have reported motility, this fact is indicated in the text. It should be noted 

 that similar uncertainties exist in regard to described cases of motility among the 

 streptococci and lactobacilli. 



