GENERAL SYSTEMATIC BACTERIOLOGY 121 



II. Names of divisions and subdivisions, of classes and subclasses are taken 

 from one of their chief characters. They are expressed by words of Greek or Latin 

 origin, some similarity of form and termination being given to those that desig- 

 nate groups of the same nature. 



III. Orders are designated preferably by the name of one of their principal 

 families, with the ending -ales. Suborders are designated in a similar manner, 

 with the ending -ineae. But other terminations may be retained for these names, 

 provided that they do not lead to confusion or error. 



Comment. The generally accepted name for the entire group of bac- 

 teria is Schizomycetes. This may be regarded as a class. The preferable 

 designation for the orders of bacteria would have the ending -ales. The 

 committee on classification of the Society of American Bacteriologists 

 has suggested the following four orders : Myxobacteriales, Thiobaderiales, 

 Chlamydobacter tales and Eubacteriales. 



Subsection 2. Names of families and subfamilies, tribes and subtribes 



Article 21. Families (Jamiliae) are designated by the name of one of their 

 genera or ancient generic names with the ending -aceae. 



Examples: Rosaceae (from Rosa), Salicaceae (from Salix), Caryophyllaceae 

 (from Dianthus Caryophyllus), etc. 



Comment. Among the family names of bacteria which have been 

 proposed and which are in correct form are : Spirillaceae from Spirillum, 

 Bacteriaceae from Bacterium, Bacillaceae from Bacillus. 



Examples of invalid families in. bacteriology are the following : Thio- 

 bacteriaceae, because there is no genus Thiobacterium, Thiorhodaceae 

 because there is no genus Thiorhodum, Trichobacteria, both because it 

 lacks the ending -aceae and because it contains no genus Trichobacterium. 



Article 22. The following names, owing to long usage, are an exception to the 

 rule: Palmae, Gramineae, Cruciferae, Leguminosae, Guttiferae, Umbelliferae, 

 Labiatae, Compositae. 



Article 23. Names of subfamilies (subfamiliae) are taken from the name of one 

 of the genera in the group, with the ending -oideae. The same holds for the 

 tribes (tribiis) with the ending -eae, and for the subtribes (subtribus) with the 

 ending -inae. 



Comment. The following subfamilies of bacteria are in proper form: 

 Chromatioideae from the genus Chromatium, Rhodobacterioideae from the 

 genus Rhodobacterium. The following are examples of names of sub- 

 families incorrectly formed: Paracoccaceae and Metacoccaceae because 

 there are no bacterial genera Paracoccus and Metacoccus, and also 

 because of an incorrect ending. An example of a tribal name would be 

 Streptococceae containing the genus Streptococcus; of a subtribe, Bacil- 

 linae containing the genus Bacillus. 



