Bacteria and Viruses 91 



Rule 24. Sect. 6. Rejection and Replacennent of Names 



RULE 24. A name must be rejected if it is illegitimate, i.e., if it is contrary 

 tc a Rule. The publication of an epithet in an illegitimate combination must 

 not be taken into consideration for purpose of priority. 

 A name of a taxon is illegitimate: 



a. If it was nomenclaturally superfluous when published, i.e., if the 

 taxon to which it was applied, as circumscribed by its author, in- 

 cluded the type of a name which the author ought to have adopted 

 under one or more of the Rules. 



b. If it is a binary or ternary name published in contravention of Prin- 

 ciple 9 and Rules 17-23, i.e., if its author did not adopt the earliest 

 legitimate epithet available for the taxon with its particular circum- 

 scription, position, and rank. 



c. If its specific epithet must be rejected under Rule 25. 



d. If it is a later homonym of the name of a taxon of bacteria, plants, 

 ov protozoa; that is, if it duplicates a name previously and validly 

 published for a taxon of the same rank based on a different type. 

 Even if the earlier homonym is illegitimate, or is generally treated 

 as a synonym on taxonomic grounds, the later homonym must be 

 rejected. When an author simultaneously publishes the same new 

 name for more than one group, the first author who adopts one of 

 them, or substitutes another name for one of them, must be followed. 

 NOTE: Mere orthographic variants of the same name are treated 

 as homonyms when they are based on different types. 



e. If it is used with different meanings and so has become a long 

 persistent source of error. A list of names (nomina ambigua) to be 

 abandoned for this reason will be included under nomina rejiciendo. 



f. !f its application is uncertain (nomen dubium). A list of names to 

 be abandoned for this reason will be included under nomina re- 

 jiciendo. 



g. If the characterization of the group was based upon an impure or 

 mixed culture. A list of names to be abandoned for this reason 

 (nomina confuso) will be included under nomina rejiciendo. 



h. If it was based upon an abnormality. 



ANNOTATIONS 



Rule 24(1. The publication of the generic name Dicrobactriim Ender- 

 lein 1917 was superfluous because of the publication of Serratia 

 Bizio 1823, based upon the same type species. Calym?natobacterinm 

 granuloinatis Aragao and Vianna 1912 has priority over Donovania 

 granulomatis Anderson, De Monbreun and Goodpasture 1945. The 

 latter name is superfluous. 



Rule 24b. The specific epithet used in the name of a species must 

 be the earliest available under the rules. The specific epithet mar- 

 cescens of the species Serratia rnarcescejis Bizio 1823 was the first 

 given, and renders illegitimate the use of the epithet of Zaogalactina 

 imetroja Sette 1824, of the epithet in Protococcus imetrophus Mene- 

 ghini 1838, and of that in Monas prodigiosa Ehrenberg 1849. 



