The Nomenclature and Classification of the Actinomycetes

Abstract

Since the publication by one of us (Waksman, 1940) of a system of classification of actinomycetes, considerable criticism was expressed in regard to the designation and position of the anaerobic pathogenic species, the cause of common actinomycosis in man and "lumpy jaw" in cattle. This type of organism was placed in the genus Cohnistreptothrix Pinoy, the generic name Actinomyces being reserved for the aerobic species forming aerial mycelium-bearing spores. This could be justified on the ground that the organism seen by Harz was so poorly described and illustrated that it is unrecognizable by present day standards , and that therefore a new name could well be applied to the organism of actinomycosis in cattle; that further the name Actinomyces was the first one applied to cultivated, aerobic, spore-forming species which can be recognized by present day standards. This has been the attitude of a number of recent medical mycologists, especially the Italian workers (Ciferri and RedaeUi, 1929; Baldacci, 1939). Critics of Waksman's classification have, however, maintained that while Harz' description of his organism is perhaps vague, there is no question concerning the nature of the disease he studied, and that the chances are overwhelmingly in favor of his having actually observed the anaerobic pathogenic filamentous organism first described by Israel. Further, under the Botanical Code, the name Actinomyces must be applied either to the organism of "lumpy jaw" or not used at all. This problem became particularly significant in view of the need for the revision of the Actinomycetaes for the sixth edition of Bergey's Manual which is being undertaken by the authors of this paper. We have been reluctant to deviate from Waksman's classification because we have felt that to abandon the name Actinomyces for the large group of aerobic spore-forming species would cause more confusion than to adopt the name Cohnistreptothrix, already in wide usage, for the anaerobic, pathogenic species. It appears, however, that under the code we have no such choice open to us. We believe that, to avoid similar dilemmas in the future, the code should be modified to permit generic names in wide usage based upon type cultures to have priority over names based merely upon morpho-logic descriptions.