A BACTERIOLOGIC STUDY OF THE DIPHTHEROID 



ORGANISMS WITH SPECIAL REFERENCE TO 



HODGKIN'S DISEASE 



PLATES 1-3 

 FREDERICK EBERSON 



From the Department of Bacteriology, Columbia University, College of Physicians and Sur- 

 geons, New York City 



I. NOMENCLATURE AND CLASSIFICATION OF THE 

 DIPHTHEROIDS 



INTRODUCTION 



Within the past few years the literature dealing with organisms of 

 the diphtheria group have received many new contributions. It seems 

 that most human and animal diseases of hitherto unknown etiology 

 have been ascribed to some sort of diphtheroid organism. Whether or 

 not these results will be confirmed has little bearing on the problem 

 which confronts the systematic bacteriologist who finds himself hard 

 put to it in attempting to classify the great number of organisms which 

 for no reason other than a slight resemblance to the diphtheria bacteria 

 have been thrown haphazardly into a group of "unknowns" the 

 diphtheroids. 



Since Loeffler's -discovery of the diphtheria organism, so many 

 so-called "pseudodiphtheria" bacteria have been mentioned in the litera- 

 ture that it seems necessary at this time to survey the field and come to 

 an understanding as to what constitutes a diphtheroid. 



In a recent paper on the "Nomenclature of the Coccaceae," 

 Buchanan has pointed out the chaotic state of bacterial nomenclature. 

 That the naming of species, genera and higher groups needs careful 

 study and revision is a foregone conclusion. A great need is felt for 

 such an analysis in the groups of bacteria which possess common char- 

 acteristics. Such a group is the diphtheroid group. 



First, it is necessary to define a "diphtheroid." The term "pseudo- 

 diphtheria" has always seemed unsatisfactory because the organisms 

 so-called differ in so many respects from the true Klebs-Loeffler organ- 

 ism as to warrant the dropping of the term from the literature except 

 in conditions to be suggested herewith. A review of the extensive 



Received for publication Feb. 6, 1918. 



