542 ORDER IV. EUBACTERIALES 



II. Strictly anaerobic. 



A. Non-motile. 



1. Cells do not show so-called false branching. 



a. Cells do not occur in long chains and/or filaments. 



Genus II. Eubacterium , p. 552. 

 aa. Cells occur in long chains and/or filaments. 



Genus III. Catenahacterium , p. 560. 



2. Cells show so-called false branching. 



Genus IV. Ramihacterium, p. 563. 



B. Motile. 



Genus V. CiUohacteriuin, p. 566. 



Gemis I. Lactobacillus Beijerinck, 1901 * 

 (Arch, neerl. d. sci. exact, et nat., Hadrlem, Ser. 2, 7, 1901, 212.) 



Lac.to.ba.cil'lus. L. noun lac, lactis milk; L. dim. noun bacillus a small rod; M.L. mas.n. 

 Lactobacillus milk rodlet. 



Rods, often long and slender. Non-motile. Gram-positive. Pigment production rare; 

 when present, yellow or orange to rust or brick-red. Gelatin is not liquefied. Growth on 

 potato is poor or absent. Glucose and similar aldehydic hexoses, carbohydrates which yield 

 these simple sugars, and polyhydroxy alcohols are changed either by homofermentation 

 to lactic acid or by heterofermentation to lactic and acetic acids, alcohol and carbon diox- 

 ide. Nitrates are not reduced except under certain conditions with Lactobacillus plantarum. 

 Several species grow at relatively high temperatures. Poor surface growth because these 

 bacteria are generally microaerophilic or anaerobic. Do not produce catalase. Found in 

 fermenting animal (especially dairy) and plant products. 



Many taxonomists continue to recognize three subdivisions of the lactic acid rods de- 

 scribed here as belonging to the genus Lactobacillus Beijerinck: Thermobacterium Orla- 

 Jensen (The Lactic Acid Bacteria, 1919, 160) and Streptobacterium Orla-Jensen {ibid, 166) 

 for the homofermentative species, and Betabacterium Orla-Jensen {ibid., 175) for the hetero- 

 fermentative types. Two of these generic names are illegitimate homonyms: Streptobac- 

 terium apparently was first used by Maggi (Jour. Micrographie, 10, 1886, 84) to designate 

 a growth form of Bacterium aceti Zopf ; Billet (Bull. Sci. de la France et de la Belgique, 

 Paris, 1890, 23) used it as a form genus to designate rod-shaped organisms which occur in 

 chains; Jacqu6 andMasay (Cent. f. Bakt., I Abt., Orig., 62, 1912, 180) defined it as a genus, 

 including Streptobacterium foetidum as a species in the genus; this organism was similar to 

 if not identical with one of the species placed in the genus Proteus Hauser. Betabacterium, 

 as a name for the heterofermentative tj^pes, is antedated by Saccharobacillus van Laer, type 

 species Saccharobacillus pastoriajius van Laer. There seems to be no more reason for sepa- 

 rating the high temperature, homofermentative lactic rods from the species that grow at 

 ordinary temperatures than there is for making a similar subdivision of the homofermenta- 

 tive lactic streptococci. Thermobacterium is therefore regarded as a synonym in part of 

 Lactobacillus Beijerinck. Lactobacterium as used by some recent authors (e.g. Krassilnikov, 

 Guide to the Bacteria and Actinomycetes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1949, 208) 

 as a substitute for Lactobacillus Beijerinck is invalid. Lactobacterium was proposed by van 

 Steenberge (Ann. Inst. Past., 34, 1920, 803) for lactobacilli in beer and beer wort; it is a 

 synonym of Lactobacillus Beijerinck. At the same time when Beijerinck proposed Lacto- 

 bacillus and van Laer proposed Saccharobacillus, the generic name Bacillus was generally 

 accepted as applying to any large, rod-shaped bacterium whether it did or did not form 

 spores, and this interpretation is in accord with the classical meaning of bacillus. In other 



*Completely revised by Prof. Carl S. Pederson, New York State Experiment Station, 

 Geneva, New York, October, 1954. 



