i H A i» I i: i{ I 



Nomenclature and General Systems of 



Classification 



Problems of Generic Nomenclature 



'llu' lirst ()rji;;iiusin l)(4()nginii; to the actiiio- 

 mycetes that was over recorded aiul to whicli 

 both a generic and a specific name were 

 gi\-en was described by Cohn in 1875 as 

 Strcptothn'.v Foersteri. Unfortunately, this 

 organism was not isolated in pure culture, 

 nor was it described sufficiently^ for identifi- 

 cation. Further, the generic name given to 

 it by Cohn had been preempted for a true 

 fungus (Corda, 1889), so that it could no 

 longer be considered as ^'alid. There was not 

 even general agreement, subsecjuently, 

 whether the organism studied by Cohn was 

 pathogenic or nonpathogenic. In spite of all 

 these objections, the name Streptothrix con- 

 tinued to be used for many years, until it was 

 finally discarded on the basis of lack of \'al id- 

 it}', in accordance with the rules of botanical 

 nomenclature. 



The second actinomycete was studied and 

 described by Harz in 1877 as Actinomyces 

 horis. Xo one now questions the fact that this 

 organism was associated with a disease con- 

 dition known as "lumpy jaw" of cattle, since 

 designated as bcjvine actinomycosis. Un- 

 fortunately, in this case as well, the organism 

 was not isolated and studied in piu'e culture 

 at that time. It is now definitely established 

 that the causative agent of actinomycosis is 

 an anaerobe. This was not fully recognized 

 at first, and subsequent isolations of aerobi(t 



cultures, many of them ;iii- contaminants, 

 tended to confuse the identity of the organ- 

 ism. The use of the generic name Ardnomijcrs 

 was finally limited to a grouj) of anaerobic 

 actinomycetes. This limitation was first 

 sponsored emphatically by Wright, who 

 suggested that this name be used only in 

 connection with the organism causing the 

 disease actinomycosis. All other actino- 

 mycetes were placed by him in the genus 

 Nocardia. There were \arious valid reasons 

 for this. He emphasized this as follows: "be- 

 cause the use of the generic term Actino- 

 myces for them logically leads to giving the 

 name actinomycosis to those cases of sup- 

 purative processes due to infection with 

 certain members of the group." 



In 1878, Rivolta suggested the name 

 Discomyces for the causative agent of a 

 disease, known as l)otryomycosis, and now 

 recognized to be due to a true bacterium. 

 The organism was considered, however, to 

 be an actinomyees. This name came into 

 limited use (Merrill and Wade), but was 

 later discarded. 



The name Nocardia was introduced in 

 188!) by Trevisan, who considered the ge- 

 neric name Actinomyces as untenable be- 

 cause the name Actinomycc (without the 

 terminal "s") was gi\'en by Meyen in 1827 

 to a tru(^ fungus, Actinomycc horkclii. How- 

 e\'er, according to the Intei-national Rules of 



47 



