GENERAL SYSTEMATIC BACTERIOLOGY 225 



Bacterium Cohn. Type : The one-flagellate, green fluorescent schizomycetes, 

 capable of growing in Cohn's nutrient solution. To these should be added all 

 the morphologically similar non-fluorescent and yellow species. Synonym: 

 Pseudomonas Migula. 



He creates the new genus Aplanobacter to replace the genus Bacterium 

 of Migula. 



Fliigge (1908) includes in the genus all rods which develop no spores. 

 He divides the genus into nine groups which are worthy of careful con- 

 sideration as generic groups. 



ElHs (1909, p. 6) follows Migula. 



Orla-Jensen (1909, p. 344) places the genus Bacterium in his family 

 Acidohacteriaceae, the type species being Bact. coli. 



Conn (1909, p. 12) defines Bacterium as a non-motile rod, contrasting 

 Bacillus which is defined as a motile rod. Heim (1911, p. 25) uses 

 Bacterium as a subhead under Bacillus to include non-spore-bearing 

 forms. 



Frost (1911, p. 57) follows Migula exactly. Schneider (1912, p. 23) 

 includes "the old genus Bacterium in the genus Bacillus." Meyer 

 (1912, p. 2) uses Bacterium as a section of the genus Bacillus including 

 those forms whose fiagella are unknown. 



Lohnis (1913, p. 45) differentiates Bacillus and Bacterium on the basis 

 of endospore production. 



Vuillemin (1913, p. 524) advocates the designation of Bacterium as a 

 Genus conservandum with a prototype Bacterium termo Ehr. and specific 

 tj^pe Bacterium pyocyaneum. This, it will be remembered, is practically 

 the recommendation of E. F. Smith. VuiUemin states that Ehrenberg 

 differentiated Bacterium from other types of Schizomycetes by its oscillat- 

 ing movement. Today, he states, we know this type of motion to be 

 due to two morphological characters, short rods and polar fiagella. 

 Bact. pyocyaneum is a short rod with polar fiagella, hence the designation 

 of this species as the type. 



Winslow et al. (Committee Society of American Bacteriologists (1917, 

 p. 561)) adopted the view of Orla-Jensen and gave the following generic 

 definition : 



Motile or non-motile rods, staining evenly. Easily cultivable. Animal 

 pathogens or saprophytes. Often chromogenic. Many forms decompose 

 carbohydrates. 



The type species is Bacterium coli Escherich. 



Buchanan (1918, p. 53) has likewise followed Orla-Jensen with the 

 definition: 



