Pellagra has existed for any length of time on the North American continent only in Mexico. Since 1864, cases of the disease have from time to time been reported in the United States. Except for a few sporadic cases, however, it is doubtful if pellagra was existent in this country prior to the year 1900. In the fall of 1906, an increasing number of puzzling cases developed at the Mount Vernon (Ala.) Asylum for insane negroes. A few such cases had been observed in the institution since the summer of 1901, but were diagnosed no more definitely than cases of "marked general debility." The rapid spread of the malady aroused the institutional authorities to a more zealous study of the disease for the purpose of control.
Dr. G. H. Searcy, assisted by Dr. Isadore Dyer, New Orleans, and Drs. McCafferty and Somerville, Mt. Vernon, worked out these cases, eighty-eight in