The object of this paper is to call attention to the presence of abnormally large numbers of organisms belonging to the B. Welchii group, which have been found in the stools of pellagrins and to inquire whether this organism may not possibly bear a causal relationship to the disease.
B. Welchii has been described by various investigators since first described by Welch and Nuttall1 in 1892 as B. aerogenes capsulatus.
For a complete description of the organism, with bibliography, reference may be made to the excellent monograph by Simonds.2
The characteristics of B. aerogenes capsulatus (B. Welchii) are as follows : It is a large gram-positive, nonmotile, anaerobic bacillus, producing spores under certain conditions. It is capable of fermenting nearly all sugars, and starch, and grows best on mediums containing these substances. In direct smears from lesions caused by it a capsule may be demonstrated. It