Though the fact may not be generally known, it is none the less true that pellagra, cases of which are frequently coming to notice in various sections of the United States, has existed among us for many years unrecognized or, probably, erroneously diagnosed, and attracted but little attention. The startling developments of the disease in its various phases in this country during the past two years have aroused such keen interest, and in some cases anxiety, in the subject of the "new" disease, from both professional and lay points of view, that it may not be a waste of serious effort to inquire into the geographical distribution of the disease. Before referring to the history and published reports as to the occurrence and incidence of the disease, it will be worth while to study briefly the early history of maize, Zea maidis, which undergoes deterioration and, thereby