For some time I have been preparing a general work on primitive superstition and religion. Among the problems which had attracted my attention was the hitherto unexplained rule of the Arician priesthood; and last spring it happened that in the course of my reading I came across some facts which, combined with others I had noted before, suggested an explanation of the rule in question. As the explanation, if correct, promised to throw light on some obscure features of primitive religion, I resolved to develop it fully, and, detaching it from my general work, to issue it as a separate study. This book is the result.
