56 International Code of Nomenclature 



Rules 9c, 9d. Designation of Nomenclaturol Types 



designation of a type species by subsequent selection. Few or none 



of these seem to be applicable in bacteriological nomenclature. 



A rule in zoology definitely fixes the use of the designation "type 



species." It reads: 



The concept of a type species of a genus is invariably to be indi- 

 cated by the expression "type species." 



The following directive is also included as a Recommendation: 

 When referring to the type species of a genus, a zoologist should 

 always use the expression "type species" rather than "genotype" 

 or any other expression. 



RULE 9cl. The nomenciatural type of a species or subspecies. The nomen- 

 clatural type of a species or subspecies may be a living culture maintained 

 in a bacteriological laboratory, more particularly in one of the international 

 or national type culture collections. 



NOTE. For a species which cannot be maintained in laboratory cultures or 

 for which neither type cultures nor neotype cultures exist, the type is the 

 original description, preparation or illustration. 



NOTE. Definitions. 



(a) The term cuhure is to be interpreted as including every method of 

 maintaining organisms in a living state (in a medium, in a host by 

 passage, in cells or exudates, or desiccated). 



(b) A type cuhure is a living culture of an organism which is a descendant 

 of the original culture or an isolation from which the author who first 

 described the organism made his original description, which culture 

 has been maintained pure, and which agrees in its characteis with 

 the original description. 



(c) A neotype cuhure is one which has been accepted by international 

 agreement to teplace a type culture which is no longer in existence. 

 It should agree with the diagnosis given by the original describer 

 and should be recommended by those workers familiar with the 

 species, and their agreed recommendation approved by the Judicial 

 Commission. 



ANNOTATIONS 



Rule 9d. Botanists and zoologists have de\eloped a series of names 



to be used in connection with the fixing of type specimens of species 



of plants and animals. 



Holotype (From the Greek, loholc or entire, the getiiiive type) . 



This is defined by the Botanical Code as follows: 



A holotype (type) is the one specimen or other element used by 

 the author or designated by him as the nomenciatural type. For so 

 long as a holotype is extant it automatically fixes the application of 

 the name concerned. 



I he definition given in zoology is: 



The single specimen designated or indicated as "the type" by the 

 original author at the time of the original publication. 



