in the world of the dead was not so strong a motive for such acts as, on the one hand, the feeling that the objects had been defiled by association with him, and on the other, the desire to give expression to the sincerity of the mourning by the destruction of valuables. On the whole, however, the immediate observances of death paled in importance before the annual communal mourning ceremony, which was everywhere, except in the Northwestern region, one of the most deeply rooted and spectacular acts of worship. Observances connected with sexual functions, including birth, are next in importance after those relating to death. The menstruating woman was everywhere regarded as unclean, and excluded especially from acts of worship. Not infrequent was the conception that she contaminated food, especially meat; in other words those varieties of food which were at once more highly prized and at the same time, through being obtained with less regularity and only through special and skilled exertions, regarded as most directly under the control and influence of supernatural powers. Among many tribes, as elsewhere in America and other continents, she was excluded from the living-house as well as from the ceremonial chamber, and confined to the menstrual hut. As elsewhere in North America, the custom in this regard however varied from tribe to tribe, the menstrual hut not having been used in some localities even in purely aboriginal times. Not only was seclusion, as a means of preventing contact and association, frequently required of the woman for the protection of others, but her refraining from all but the most necessary activity was sometimes deemed essential for her own good.