BACILLUS MPHTHERLE 



585 



suggested the term corynebacterium. The characteristics of this group 

 are a morphological similarity to the diphtheria bacillus, that they are 

 Gram-positive, non-motile, often show metachromatic granules and 

 have no spores. It is not, at the present writing, possible to formulate 

 a classification of these organisms. They are apparently very numer- 

 ous and have been isolated from a great many different sources, both 



in connection with the human body and in nature. Recently Bunting 

 and Yates have claimed that an organism of this group has etiological 

 connection with Hodgkin's disease. Studies by many other workers, 

 notably by Bloomfield and Fox,- and studies going on in 1 our own labora- 

 tory show that organisms very similar to these strains can be isolated 

 from the skin, from the lymph nodes of healthy and diseased people, 

 from ascitic fluid in varying conditions, and from supposedly sterile 

 tissues. They are frequently present in the nasal mucus and in the 

 throat, and are so ubiquitous that any association of them with specific 

 disease must be very conservatively approached. According to the 

 investigations of many men who have studied the flora of the naso- 

 pharynx, it seems that organisms belonging to the general group of 

 diphtheroid bacilli are the most common saprophytes habitually present 

 in this part of the normal human body. 



Very similar to this group are the bacilli of pseudo-tuberculosis ovis, 

 isolated from necrotic lesions in the kidneys of sheep by Preisz and 

 Nocard. 



It is impossible at present to do more than indicate that the " diph- 

 theroid bacilli" are a large heterogeneous group, held together by 

 morphological and superficial cultural similarity and largely consisting 

 of saprophytes and probably harmless parasites on the human and 

 animal body. 



Recently, Mallory and Frederic Parker have isolated diphtheroid 

 bacilli from middle ear lesions secondary to scarlet fever which seem to 

 deserve more than ordinary attention because of their apparent produc- 

 tion of a powerful toxic substance. These organisms are now being 

 studied in our laboratory by Dr. Parker. 



