Bacteria and Viruses 97 



Rule 26. Sect. 6. Rejection and Replacement of Names 



RULE 26. The name or epithet to be rejected according to Rules 23-25 is 

 replaced by the oldest legitimate name, or (in a combination) by the oldest 

 legitimate epithet which will be, in the new position, in accordance with the 

 Rules. If none exists, a new name or epithet must be chosen. 



NOTE. Where a new epithet is required, an author may, if he wishes, adopt 

 an epithet previously given to the taxon in an illegitimate combination, if 

 there is no obstacle to its employment in the new position or sense; the 

 resultant combination is treated as a new name. 



ANNOTATIONS 



Rule 26. The Botanical Code has essentially the same wording. 



This is the application of the Law of Priority, clearly stated in 

 Principle 9. Examples: The generic name Polyayigiiim Link 1809 

 replaced the generic name Myxobacter Thaxter 1892 when the earlier 

 name with description was found by Thaxter. Similarly the species 

 name Myxobacter aureus Thaxter 1893 became a synonym of Poly- 

 angiwn vitellinum Link 1809. 



The species Bacterium aeruginosiun Schroeter 1872 was later in- 

 dependently named Bacillus pyocyaneus by Gessard 1882. Migula 

 proposed the new generic name Pseudomonas and recognized the 

 specific epithet having priority, in Pseudomonas aeruginosa (Schroe- 

 ter) Migula. 



The Zoological Code under Law of Priority states that the name 

 to be used for a genus or for a species must be the oldest name that 

 fulfills three requirements. (1) The name must have been published 

 and have been accompanied by an indication, or a definition, or a 

 description of the taxon to which it appertains. (2) The author of 

 the name must have consistently applied the principles of binominal 

 nomenclature in the publication. (3) Any name published after 

 1930 must have had included in its publication a statement by the 

 author in which he attempted to indicate the distinguishing charac- 

 ters of the taxon. Further, if published as a substitute for a rejected 

 homonym, the publication must give a reference to the name re- 

 placed. If the name published is that of a genus or subgenus, it must 

 have been published with a type species designated or indicated in 

 accordance with the Rules prescribed for determining the type 

 species solely on the basis of the original publication. 



