GENERAL SYSTEMATIC BACTERIOLOGY 169 



Orla-Jensen (1909) gives Actinomycetes as the name of the second 

 family of the bacterial order Cephalotrichinae. He includes in it four 

 genera, Rhizomonas Jensen, Corynemonas Jensen, Mycomonas Jensen, 

 and Actinomyces Harz. The designation has been extensively used in 

 the literature as a group name. 



It would seem that the form Aciinomycetaceae would better fit no- 

 menclatural usage in accordance with Article 21 of the botanical code, 

 and in this form would be a valid family name. 



Aerobacter. A generic name proposed by Beijerinck (1900, p. 

 198) for certain gas producing bacteria of the so-called "colon" group. 

 In sugar solutions all are facultative anaerobic, all ferment dextrose 

 and levulose with the formation of levo-rotatory lactic acid and usually 

 with production of gas as well. The gas is a mixture of carbon dioxide 

 and hydrogen. Sulfates are never reduced, while nitrates are readily 

 reduced with formation of nitrites, but never of ammonia. No spores 

 are formed. The organisms are easily killed by heating to 65°C. The 

 cells are frequently motile, either peritrichous or monotrichous. The 

 temperature optimum is about 28°C. The following are the best 

 known species which he lists. 



Aerobacter aerogenes {Bacillus lactis aerogenes Escherich) 

 A. coli (with many varieties, best known, commune) 

 A. viscosum 

 A. liquefaciens (Digests gelatine, monotrichous) 



Buchanan (1918, p. 53) used this as a subgeneric designation for 

 the colon group of the genius Bacterium, with the following diagnosis: 

 "Fermenting both glucose and lactose with formation of both acid and 

 gas. Pathogenicity sHght." The type species was designated as 

 Bacterium {Aerobacter) coli. This is probably to be regarded as an 

 error. A reading of the characterization of the genus by its author 

 emphasizes that Bacterium (Aerobacter) aerogenes is, instead, the type 

 for in the Hst and description of species the latter organism is first 

 given. 



Beijerinck (p. 197) emphasizes that this group is to be regarded 

 as a true genus and not merely a physiological genus such as his 

 Photobacter 



Aerobacter is rejected by Smith (1905, p. 174). 



An Aerobacter tartarivorum was named by Nijdam (1907), 



Enlows (1920, p. 13) gives the following characterization of the 

 genus. 



