370 S. R. GIFFORD 



be isolated from the spore-bearer. It seemed possible that the 

 spore-bearers were a form of the fusiform bacilli appearing when 

 it was grown aerobically and especially on solid media. But 

 remembering that Weaver and TunniclirT and also Abel found 

 the same intimate relation of the bacilli to the aerobic cocci in 

 isolated colonies, it seemed more likely that the spore-bearer 

 was another organism present in the larynx or as a contaminant 

 in the culture, whose aerobic growth furnished the conditions 

 necessary for the growth of the more anaerobic fusiform bacillus. 

 With regard to the staining characters, the fusiforms in the 

 cultures varied markedly and with no ascribable relation to the 

 conditions present. The question of the pathogenicity of this 

 strain was not determined by animal experiment. Though 

 found in such profusion in the lesions, it may have been only a 

 secondary invader from the teeth following streptococcic infection. 

 In summing up, it may be said : 



1. Bacilli were found to be more numerous than spirilla in 

 17 out of 24 examinations. 



2. The fusiform bacilli of Vincent's angina show much greater 

 variation in their Gram-staining properties than ordinary organ- 

 isms. Where there were any number of bacilli present, smears 

 were never found which did not show both Gram-positive and 

 Gram-negative bacilli in the same smear. Many were found 

 in nearly all smears which were Gram-negative with Gram- 

 positive granules, most frequently 4 granules in a pair of bacilli, 

 but this number varied. These Gram-positive granules seem 

 to be one of the most constant mophological characteristics of 

 the organisms, almost as constant and distinctive as the polar 

 bodies in Mycobact. diphtheriae. 



3. A slight predominance of Gram-positive organisms was 

 noted, but not great enough to justify any conclusions. 



4. Method of staining is not responsible for the variation noted. 



5. The fusiform bacilli may be cultivated anaerobically or 

 aerobically when other aerobic organisms are present. They 

 could not be isolated by our methods, though others have suc- 

 ceeded in doing so. 



