GENERAL SYSTEMATIC BACTERIOLOGY 135 



or Fries (Systema), to the state containing the form which is generally regarded 

 as being perfect, on condition that in other respects it conforms to the rules. 



The ascus stage is considered the perfect state in the Ascomycetes, the basidia 

 as the stage in the Basidiomycetes, the teleutospore or its equivalent in the 

 Uredinales, and the spore in the Ustilaginales. 



Generic and specific names given to other stages possess only a temporary value . 

 They are not to be used to replace a generic name already existing and applied to 

 one or more species, any one of which contains the form termed perfect. 



The nomenclature of fungi with an evolutionary cycle, but not pleomorphic 

 follows the ordinary rules of nomenclature. 



Recommendations. XXIX. 1°. When a sub-tribe becomes a tribe, when a 

 tribe becomes a subfamily, when a subfamily becomes a family, etc., or when the 

 inverse changes occur, do not alter the root of a name but only the termination 

 (-inae, -eae, -oideae, -ineae, -ales, etc.), unless in the new position, one of the 

 obstacles indicated in the articles of section 7, supervenes, or the new designation 

 becomes a source of error, or there is some other serious reason against it. 



2°. When a section or a subgenus becomes a genus, or the inverse changes take 

 place, retain the old names, unless this results in two genera of plants having the 

 same name, or the existence of two subdivisions of the same name in the same 

 genus, or one of the obstacles indicated in the articles of section 7 supervenes. 



3°. When a subdivision of a species becomes a species or the inverse change 

 occurs, retain the original epithets, unless this results in two species bearing the 

 same name in the same genus, or two subdivisions bearing the same name in the 

 same species, or unless any of the obstacles indicated in section 7 supervenes. 



Section 7. On names that are to he rejected, changed or modified 



Article 50. No one is authorized to reject, change or modify a name (or com- 

 bination of names) because it is badly chosen, or disagreeable, or another is pref- 

 erable or better known, or because of the existence of an earlier homonym which 

 is universally regarded as non-valid, or for any other motive either contestable or 

 of little import. (See also art. 57.) 



Recommendations. See on the subject of homonyms recommendations Vb 

 and XIV which suggest that cases of this kind should be avoided for the future. 



Comment. A large proportion of the names which have been suggested 

 for genera and species of bacteria must be rejected because of violation 

 of this article. Orla-Jensen (1909) for example, created a large number 

 of new genera, in order to make them conform to his ideas of fitness. 

 Where such names are applied to groups which have had no previous 

 generic designation they are, of course, valid, but he was not justified 

 in substituting names which he preferred for old and valid designations. 



The expression "because of the existence of an earlier homonym which 

 is universally regarded as non-valid" is one which permits of a variety 

 of interpretations. The zoologists insist upon the rejection of any name 

 which is a homonym of an earlier term. In this respect the two codes 

 are at variance. 



