The debt to my almost constant field companion, Charles Apekaum (Kiowa), game warden, ex-Navy man, graduate of Chilocco, Haskell, and Carlisle, and my chief interpreter, is such that I may say my work could not have been carried out with such comparative facility and speed without his aid. His knowledge of people and places was invaluable to me. Special appreciation is expressed to Mr. Alfred Wilson (Cheyenne) of Thomas, Oklahoma, several times state president of the Native American Church, for lending me numerous letters and other documents from the official files of the organization, and to Jim Waldo (Kiowa) and Kiowa Charley for similar documents, including the articles of incorporation and state charter. To Jim Pettit (Oto) of Red Rock, local president of the Native American Church, and Charles Tyner (Quapaw) of Miami, the added debt of personal hospitality was incurred. The following informants were of particular help in gathering data: Cecil and Henry Murdock (Kickapoo); Sly Picard, George May and Henry Hunt (Wichita); Jim Aton, Belo Kozad and Homer Buffalo (Kiowa); Howard White Wolf (Comanche); Carl Pettit, Murray Little-crow, and Mrs. George Pipestem (Oto); Albert Stamp (Seminole); Tom and Collins Panther (Shawnee); Tennyson Berry (Kiowa Apache); Robert Little-dance and Louis MacDonald (Ponca); Mack Haag (Cheyenne); Elijah Reynolds (Delaware); and Sun Chief and James Sun-eagle (Pawnee). To Jonathan Koshiway (Oto), founder of the Church of the First-born, I wish to express appreciation for his painstaking efforts at completeness of information made on my behalf.